JP2006157855A - Information recording medium, image encoding method, and image decoding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a P picture, which is the first field of a P / I picture, from being decoded at the time of seamless connection or multi-angle playback when the head of a random access unit is a P / I picture in VC-1, and the resolution is halved There was a problem of becoming.
When a flag for identifying a closed GOP type RAU is set, a P / I picture is not arranged at the head of the RAU. In the image decoding apparatus, means for switching the display operation depending on whether or not the head of the RAU is a P / I picture becomes unnecessary.
[Selection] Figure 34

Description

  The present invention relates to an image encoding method and an image decoding method for encoding auxiliary information effective during special reproduction such as seamless connection and multi-angle reproduction, and a stream thereof.

  In recent years, with the era of multimedia that handles sound, images, and other pixel values in an integrated manner, conventional information media, that is, means for transmitting information such as newspapers, magazines, televisions, radios, telephones, etc., to people have become multimedia. It has come to be taken up as a target. In general, multimedia refers to not only characters but also figures, sounds, especially images, etc. that are associated with each other at the same time. It is an essential condition.

  However, when the information amount of each information medium is estimated as a digital information amount, the amount of information per character is 1 to 2 bytes in the case of characters, whereas 64 Kbits (phone quality) per second in the case of speech. In addition, for a moving image, an information amount of 100 Mbits (current television reception quality) or more per second is required, and it is not realistic to handle the enormous amount of information in the digital format as it is with the information medium. For example, a video phone has already been put into practical use by an integrated services digital network (ISDN) having a transmission speed of 64 Kbit / s to 1.5 Mbits / s. It is impossible to send.

  Therefore, what is required is information compression technology. For example, in the case of a videophone, H.264 recommended by ITU-T (International Telecommunication Union Telecommunication Standardization Sector). 261 and H.264. H.263 standard video compression technology is used. In addition, according to the information compression technology of the MPEG-1 standard, it is possible to put image information together with audio information on a normal music CD (compact disc).

  Here, MPEG (Moving Picture Experts Group) is an international standard for video signal compression standardized by ISO / IEC (International Electrotechnical Commission). This is a standard for compressing information of a television signal up to 5 Mbps, that is, about 1/100. In addition, since the MPEG-1 standard sets the target quality to a medium quality that can be realized mainly at a transmission rate of about 1.5 Mbps, the MPEG-2 standardized to meet the demand for higher image quality. Then, the TV broadcast quality is realized at 2 to 15 Mbps for the moving image signal. Furthermore, at present, the working group (ISO / IEC JTC1 / SC29 / WG11) that has been standardizing with MPEG-1 and MPEG-2 achieves a compression ratio that exceeds MPEG-1 and MPEG-2, and further, in units of objects. MPEG-4 has been standardized that enables encoding, decoding, and operation, and that realizes new functions required in the multimedia era. In MPEG-4, it was originally aimed at standardizing a low bit rate encoding method, but now it has been extended to a more general encoding including a high bit rate including interlaced images. Thereafter, MPEG-4 AVC (Advanced Video Coding) was jointly developed by ISO / IEC and ITU-T as a next-generation image coding method with a higher compression rate, and now SMPTE (Society of Motion Picture and Television Engineers). VC-1 (Non-Patent Document 1) is being standardized. In VC-1, the encoding tool and the like are expanded based on the MPEG-2 and MPEG-4 systems. Of these, VC-1 is expected to be used in next-generation optical disc related devices such as BD (Blu-ray disc) and HD (High Definition) -DVD.

  In general, in encoding of moving images, the amount of information is compressed by reducing redundancy in the time direction and the spatial direction. Therefore, in inter-picture predictive coding for the purpose of reducing temporal redundancy, motion is detected and a predicted image is created in units of blocks with reference to the forward or backward picture, and the resulting predicted image and the encoded image are encoded. Encoding is performed on the difference value from the target picture. Here, a picture is a term representing a single screen, which means a frame in a progressive image and a frame or field in an interlaced image. Here, an interlaced image is an image in which one frame is composed of two fields having different times. In interlaced image encoding and decoding processing, one frame can be processed as a frame, processed as two fields, or processed as a frame structure or a field structure for each block in the frame. .

  A picture that does not have a reference picture and performs intra prediction coding is called an I picture. A picture that performs inter-frame predictive coding with reference to only one picture is called a P picture. A picture that can be subjected to inter-picture prediction coding with reference to two pictures at the same time is called a B picture. The B picture can refer to two pictures as an arbitrary combination of display times from the front or the rear. However, as a condition for encoding and decoding these pictures, the picture to be referenced needs to be already encoded and decoded.

  Next, the stream structure of VC-1 will be described. VC-1 also basically has the same stream structure as MPEG-2. However, the random access point is called an entry point (Entry Point), and a header (Entry Point Header) is added to the entry point. Data from an entry point to the next entry point is a random access unit and corresponds to GOP (Group of Pictures) in MPEG-2. Hereinafter, the random access unit in VC-1 is referred to as RAU (Random Access Point). Here, in the RAU, user data (entry point level user data) regarding the pictures constituting the RAU can be stored, and is stored immediately after the entry point header.

  The types of pictures in VC-1 are shown below. First, I, P, and B pictures have a prediction structure equivalent to that of MPEG-2, but in addition to these three kinds of pictures, two kinds of Skipped pictures and BI pictures are defined. A skipped picture is a picture that does not include pixel data, and is handled as a P picture having the same pixel data as the immediately preceding reference picture in decoding order. For example, in the following example, since S6 is considered to be the same as P4, the operation at the time of decoding the stream is the same in (1) and (2).

(1) Display order: I0 B1 P2 B3 P4 B5 S6 (S indicates a skipped picture)
(2) Display order: I0 B1 P2 B3 P4 B5 P4
The skipped picture is particularly effective when the image is stationary. For example, when the image is stopped from the middle of the RAU, I0 P1 P2 P3 S4 S5 S6. . As described above, the code amount can be reduced by using a skipped picture for a portion where the image is stationary. A BI picture is a picture having both the characteristics of a B picture and an I picture. Specifically, the order of decoding and display is different, and it has the property of a B picture in that it is not referenced from other pictures, and all macroblocks are intra-coded and do not refer to other pictures. It has the characteristics of an I picture at a point.

  Next, a method for discriminating I, P, B, Skipped, and BI pictures will be described. Basically, the picture type can be determined by referring to the picture type of the picture layer, but the picture type that can be indicated by the picture layer is defined as follows according to the profile.

Simple profile: I, P
Main profile: I, P, B, BI
Advanced Profile: I, P, B, BI, Skipped

  Here, in both the simple and main profiles, the skipped picture cannot be determined from the picture type of the picture layer. Therefore, when the size of a picture having an arbitrary picture type is 1 byte or less, the picture is a skipped picture. It is prescribed. In the main profile, a picture type indicating a B or BI picture is defined, and the B picture and the BI picture cannot be distinguished from the picture type.

  The VC-1 RAU also has an open GOP type and a closed GOP type as in MPEG-2. The closed GOP type is a type in which the B picture in the RAU does not refer to the I picture or P picture in the immediately preceding RAU in the decoding order. On the other hand, the open GOP type is a type in which a B picture in an RAU may refer to an I picture or P picture in the immediately preceding RAU in decoding order. In both the open type and the closed type, the I picture and P picture in the RAU cannot refer to the I picture and P picture in the immediately preceding RAU in the decoding order.

  Next, the types of fields constituting one frame at the time of field encoding will be described. In VC-1, only the advanced profile supports field coding, and the picture type of the first field and the second field at the time of field coding is indicated by the field picture type in the picture layer. The field picture type is (I, I), (I, P), (P, I), (P, P), (B, Eight types of B), (B, BI), (BI, B), and (BI, BI) are defined. Hereinafter, these pictures are referred to as I / I picture, I / I picture, I / P picture, P / I picture, P / P picture, B / B picture, B / BI picture, BI / I picture, BI / This is called a BI picture. Here, the two fields constituting one frame are called field pairs. The above eight pictures such as I / P pictures are referred to as pictures, but are all field pairs. In MPEG-2, there are no P / I picture, B / BI picture, BI / I picture, and BI / BI picture.

FIG. 35 is a block diagram of an image encoding device 1 that implements a conventional image encoding method.
The image encoding device 1 is a device that outputs an image encoded signal Str obtained by compressing and encoding an input image signal Vin and converting it into a bit stream such as variable length encoding, and includes a motion detection unit ME and a motion compensation unit MC. , Subtracting unit Sub, orthogonal transform unit T, quantization unit Q, inverse quantization unit IQ, inverse orthogonal transform unit IT, addition unit Add, picture memory PicMem, switch SW, and variable length coding unit VLC.

  The image signal Vin is input to the subtraction unit Sub and the motion detection unit ME. The subtraction unit Sub calculates a difference value between the input image signal Vin and the predicted image and outputs the difference value to the orthogonal transform unit T. The orthogonal transform unit T converts the difference value into a frequency coefficient and outputs it to the quantization unit Q. The quantization unit Q quantizes the input frequency coefficient and outputs the quantized value Qcoef to the variable length coding unit.

  The inverse quantization unit IQ inversely quantizes the quantized value Qcoef to restore the frequency coefficient, and outputs the frequency coefficient to the inverse orthogonal transform unit IT. The inverse orthogonal transform unit IT performs inverse frequency conversion from the frequency coefficient to the pixel difference value, and outputs the result to the addition unit Add. The addition unit Add adds the pixel difference value and the predicted image output from the motion compensation unit MC to obtain a decoded image. The switch SW is turned ON when an instruction to store the decoded image is given, and the decoded image is stored in the picture memory PicMem.

  On the other hand, the motion detection unit ME to which the image signal Vin is input in units of macroblocks uses the decoded image stored in the picture memory PicMem as a search target and detects the position by detecting the image region closest to the input image signal. A motion vector MV to be pointed is determined.

  In the motion compensation unit MC, using the motion vector detected by the above processing, an image region optimal for the predicted image is extracted from the decoded image stored in the picture memory PicMem.

  If the target picture is the start position of the RAU by the RAU start picture RAUin, the picture prediction structure determination unit PTYPE encodes the target picture as a special picture that can be randomly accessed (intra-screen coding). Then, the motion detection unit ME and the motion compensation unit MC are instructed, and the picture type Ptype is encoded by the variable length encoding unit VLC. Here, I / I, I / P, and P / I pictures can be freely selected as picture types when the first picture is encoded as a field.

  The variable length coding unit VLC performs variable length coding on the quantized value Qcoef, the picture type Ptype, the motion vector MV, and the like to obtain an encoded stream Str.

  FIG. 36 is a block diagram of an image decoding device 3 that implements a conventional image decoding method. In the figure, units that perform the same operations as those in the block diagram of the image encoding device 1 in FIG. The variable length decoding unit VLD decodes the encoded stream Str and outputs a quantized value Qcoef, a relative index Index, a picture type Ptype, and a motion vector MV. The quantized value Qcoef, the relative index Index, and the motion vector MV are input to the picture memory PicMem, the motion compensation unit MC, and the inverse quantization unit IQ, and the decoding process is performed. The operation is the conventional image encoding method of FIG. This has already been described with reference to a block diagram of an image encoding device that implements The buffer memory BufMem is a memory that stores the decoded image Vout. When the next picture to be displayed is the first picture of the RAU, the display method switching unit ModeSet acquires data Pinf necessary for acquiring the picture type from the decoded image data stored in the buffer memory BufMem. Further, when the picture is a P / I picture, the display unit Disp is notified by the display command mode that the same image is displayed in the first field and the second field. If it is not a P / I picture, the first field and the second field instruct the display unit Disp to display the first field and the second field in the field pair constituting one frame, respectively. The display unit Disp acquires the decoded image Din from the buffer memory BufMem and displays it according to the display command mode. The picture memory PicMem and the buffer memory BufMem may be shared.

FIG. 37 is a flowchart showing a display operation during special playback such as multi-angle playback or continuous playback of different sections in the same stream in the conventional image decoding device 3. First, in step S1001, it is determined whether the picture to be displayed is the first picture in the RAU. If it is the first picture, the process proceeds to step S1002, and if it is not the first picture, the process proceeds to step S1005. In step S1002, the picture type of the picture is acquired, and it is determined whether or not it is a P / I picture in step S1003. If it is a P / I picture, the process proceeds to step S1004. If it is not a P / I picture, the process proceeds to step S1005. In step S1004, it is determined that the second field is displayed twice. That is, in the P / I picture, since the P picture that is the first field cannot be decoded, the I picture that is the second field is displayed instead of the P picture. In step S1005, it is determined that the first field and the second field constituting the field pair are displayed in order.
JP 2000-228656 A Proposed SMPTE Standard for Television: VC-9 Compressed Video Bitstream Format and Decoding Process, Committee Draft 1, 2004.19.

  When the leading picture of the RAU is a P / I picture, there is a problem that the P picture, which is the first field of the P / I picture, cannot be played back during special playback such as jump playback or multi-angle playback. In addition, when the head of the RAU is a P / I picture, it is necessary to switch the display operation to a picture other than the P / I picture by repeatedly displaying the second field, etc. There was also a problem of increasing. Hereinafter, problems during special reproduction will be described.

  As shown in FIG. 27, it is also possible to use a P / I picture as the leading picture of the RAU. The head of the RAU is a position that can be designated as a playback start point in special playback or the like. However, when playback is started from an RAU that has a P / I picture as the head picture, the P picture that is the first field is It cannot be decoded because it refers to another picture in front. Therefore, decoding is started from the I picture that is the second field, and when displaying the image of the frame that is the P / I picture, the frame is displayed only from the image of the second field. For example, by outputting the second field image twice, one frame image is displayed.

  Furthermore, as shown in FIG. 28, in the case of special reproduction such as fast-forward reproduction in which only the RAU head picture is read, P picture cannot be decoded in the same way, so only one field in one frame can be decoded, and the resolution is halved. There is a fault that falls.

  Also, for DVD, BD, etc., special playback such as continuous playback of streams at different time positions in the same stream using a playlist, or continuous playback of streams constituting different angles during multi-angle playback is common. Done. Further, in a write-once or rewritable disc, the edited streams may be virtually linked by a playlist. At this time, in the playlist, playback sections called play items are continuously played back. FIG. 29 shows an example in which the first play item and the second play item pointed to by the play list are continuously reproduced. Here, if the first picture of the second play item is a P / I picture, the P picture constituting the P / I picture cannot be decoded, and a seamless connection from the first play item to the second play item cannot be realized. .

The present invention has been made to solve the above problems.
An information recording medium according to claim 1 of the present invention is an information recording medium in which at least a stream in which encoded data of a moving image is multiplexed and management information thereof are recorded, and the management information is a moving image in the stream. Reproduction time information, size information, and start address information in the stream, and the encoded data of the moving image is composed of one or more randomly accessible units, and in the encoding method of the moving image When encoding one frame image in units of fields, when the field pair encoded with the first field as a forward prediction picture and the second field as an in-plane encoded picture can be used, The identification information indicating whether or not the field pair exists in stored data is stored.

  In the information recording medium according to claim 2 of the present invention, the bidirectional access picture in the random access unit is prohibited from referring to the picture in the immediately preceding random access unit in the decoding order in the random access unit. There are two types: closed-type random access units and open-type random access units that allow bi-predictive pictures in random access units to refer to pictures in the previous random access unit in decoding order. And the identification information is information indicating whether or not the random access unit is a closed type. When the random access unit is a closed type, the field pair is present at the head of the random access unit. The information recording medium according to claim 1, wherein the information recording medium is not.

  The information recording medium according to claim 3 of the present invention is characterized in that the identification information is information indicating whether a bit rate of the encoded stream is equal to or lower than a predetermined value. It is a recording medium.

  In the information recording medium according to a fourth aspect of the present invention, the moving image is divided into a plurality of reproduction sections according to a reproduction time, and the management information includes one or more reproduction sections in one or more moving images. Information for playback is stored, and the identification information is stored in the management information and indicates whether the playback sections that are continuously played back are seamlessly connected, and is seamlessly connected. The information recording medium according to claim 1, wherein the head of the playback section as a connection destination is not the field pair.

  In the information recording medium according to claim 5 of the present invention, the moving image is divided into a plurality of reproduction sections according to the reproduction time, and the management information includes one or more reproduction sections in one or more moving images. Information for playback, and the identification information is information that is stored in the management information and identifies whether or not the sections that are continuously played belong to different video streams, When it is indicated that they belong to the different video streams, the head of the playback section as a connection destination is not the field pair.

  An image encoding method according to a sixth aspect of the present invention is an image encoding method for encoding a moving image in one or more random access units. In the moving image encoding method, an image of one frame is encoded. When a field pair encoded with a first field as a forward prediction picture and a second field as an in-plane encoded picture can be used when encoding in field units, the first picture of the random access unit is Auxiliary information creating step for creating information indicating whether the pair is a field pair, and an encoding step for coding the created auxiliary information and pixels to create an encoded stream are provided.

  An image encoding apparatus according to a seventh aspect of the present invention is an image encoding apparatus that encodes a moving image in one or more random access units. In the moving image encoding method, an image of one frame is encoded. When a field pair encoded with a first field as a forward prediction picture and a second field as an in-plane encoded picture can be used when encoding in field units, the first picture of the random access unit is Auxiliary information creating means for creating information indicating whether the pair is a field pair, and coding means for coding the created auxiliary information and pixels to create a coded stream are provided.

  An image decoding method according to an eighth aspect of the present invention is an image decoding method for decoding and reproducing the encoded data recorded on the information recording medium of the first aspect, wherein the random access unit is decoded based on the identification information. And a display step of displaying the first field and the second field in the first picture in the first and second directions, respectively, when it is indicated that the first picture is not the field pair.

  An image decoding apparatus according to a ninth aspect of the present invention is an image decoding apparatus that decodes and reproduces the encoded data recorded on the information recording medium of the first aspect, wherein the random access unit is determined based on the identification information. Display means for displaying the first field and the second field in the first picture first and second respectively when the first picture is indicated not to be the field pair.

  An information recording medium according to a tenth aspect of the present invention is an information recording medium that records at least a stream in which encoded data of moving images is multiplexed and management information thereof, and the management information is a moving image in the stream. Reproduction time information, size information, and start address information in the stream, and the encoded data of the moving image is composed of one or more randomly accessible units, and in the encoding method of the moving image When a field pair encoded with a first field as a forward-predicted picture and a second field as an in-plane encoded picture can be used when an image of one frame is encoded in units of fields, the random field When the picture different from the head of the access unit is the field pair, the picture in the random access unit Thus, a picture whose display order is later than the field pair is guaranteed not to refer to the first field of the field pair, and information indicating the guarantee is stored in the stream. It is characterized by.

  An information recording medium according to an eleventh aspect of the present invention is an information recording medium in which at least a stream in which encoded data of a moving image is multiplexed and management information thereof are recorded, and the management information is a moving image in the stream. Reproduction time information, size information, and start address information in the stream, and the encoded data of the moving image is composed of one or more randomly accessible units, and in the encoding method of the moving image When a field pair encoded with a first field as a forward-predicted picture and a second field as an in-plane encoded picture can be used when an image of one frame is encoded in units of fields, the random field When the picture different from the head of the access unit is the field pair, the picture in the random access unit Thus, the picture whose display order is later than the field pair may or may not refer to the first field of the field pair, and the picture whose display order is later than the field pair. Stores in the stream information indicating whether to refer to the first field of the field pair.

  An information recording medium according to a twelfth aspect of the present invention is an information recording medium in which at least a stream in which encoded data of a moving image is multiplexed and management information thereof are recorded, and the management information is a moving image in the stream. Reproduction time information, size information, and start address information in a stream, and the encoded data of the moving image is data in which a plurality of grouping units each including one or more pictures are concatenated, The management information stores the list information of the grouping units that can be randomly accessed. In the moving image encoding method, the first field is moved forward when the image of one frame is encoded in the field unit. When a pair of fields encoded as a predictive picture and a second field as an intra-coded picture can be used, the stream is Wherein the leading picture of the grouping units not pointed from the list information stores information indicating whether the field pair.

  As described above, according to the present invention, when using a P / I picture, the playback quality during special playback can be improved by restricting the stream and management information, and the special playback function is emphasized. In particular, its practical value is high.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
First, a first embodiment of the present invention will be described.

(Logical data structure on disk)
FIG. 1 is a diagram showing a configuration of a BD-ROM, particularly a configuration of a BD disc (104) that is a disc medium and data (101, 102, 103) recorded on the disc. The data recorded on the BD disc (104) is AV data (103), BD management information (102) such as management information related to AV data and an AV playback sequence, and a BD playback program (101) that realizes interactive processing. . In the present embodiment, for convenience of explanation, the BD disc is mainly described with reference to an AV application for playing back AV content of a movie.

  FIG. 2 is a diagram showing a directory / file structure of logical data recorded on the BD disc. A BD disc has a spiral recording area from its inner periphery to its outer periphery, like other optical discs such as DVDs and CDs, and stores logical data between the inner lead-in and outer lead-out. It has a logical address space that can be recorded. Further, inside the lead-in, there is a special area that can be read only by a drive called BCA (Burst Cutting Area). Since this area cannot be read from an application, it may be used for copyright protection technology, for example.

  Application data such as video data is recorded in the logical address space with file system information (volume) at the head. As described in the prior art, the file system is UDF, ISO9660 or the like, and logical data recorded in the same way as a normal PC can be read using a directory and file structure. .

  In the case of this embodiment, the directory and file structure on the BD disc is a BDVIDEO directory placed directly under the root directory (ROOT). This directory is a directory in which data (101, 102, 103 described in FIG. 1) such as AV contents and management information handled by the BD is stored.

  The following seven types of files are recorded under the BDVIDEO directory.

BD. INFO (fixed file name)
This is one of “BD management information” and is a file in which information related to the entire BD disc is recorded. The BD player first reads this file.

BD. PROG (fixed file name)
It is one of “BD playback programs” and is a file in which playback control information related to the entire BD disc is recorded.

XXX. PL ("XXX" is variable, extension "PL" is fixed)
It is one of “BD management information” and is a file in which playlist information that is a scenario (playback sequence) is recorded. I have one file per playlist.

XXX. PROG ("XXX" is variable, extension "PL" is fixed)
It is one of “BD playback programs” and is a file in which playback control information for each playlist is recorded. Correspondence with a playlist is identified by a file body name (“XXX” matches).

YYY. VOB ("YYY" is variable, extension "VOB" is fixed)
It is one of “AV data” and is a file in which VOB (same as VOB described in the conventional example) is recorded. There is one file for each VOB.

YYY. VOBI ("YYY" is variable, extension "VOBI" is fixed)
It is one of “BD management information” and is a file in which stream management information related to VOB as AV data is recorded. The correspondence with the VOB is identified by the file body name (“YYY” matches).

ZZZ. PNG ("ZZZ" is variable, extension "PNG" is fixed)
It is one of “AV data” and is a file in which image data PNG (image format standardized by W3C and read as “ping”) for composing subtitles and menus is recorded. There is one file for each PNG image.

(Player configuration)
Next, the configuration of the player that plays the above-described BD disc will be described with reference to FIGS. 6 and 7. FIG.

FIG. 3 is a block diagram showing a rough functional configuration of the player.
Data on the BD disc (201) is read through the optical pickup (202). The read data is transferred to a dedicated memory according to the type of each data. The BD playback program (the contents of the “BD.PROG” or “XXX.PROG” file) is stored in the program recording memory (203) in the BD management information (“BD.INFO”, “XXX.PL” or “YYY.VOBI”). Are transferred to the management information recording memory (204), and the AV data ("YYY.VOB" or "ZZZ.PNG") are transferred to the AV recording memory (205).

  The BD playback program recorded in the program recording memory (203) is recorded by the program processing unit (206), and the BD management information recorded in the management information recording memory (204) is recorded by the management information processing unit (207). The AV data recorded in the memory (205) is processed by the presentation processing unit (208).

  The program processing unit (206) receives event information such as playlist information to be played back and program execution timing from the management information processing unit (207), and processes the program. Also, the program can dynamically change the play list to be played back. In this case, the play list play command is sent to the management information processing unit (207). The program processing unit (206) receives an event from the user, that is, a request from the remote control key, and executes a program corresponding to the user event if there is a program.

  The management information processing unit (207) receives an instruction from the program processing unit (206), analyzes the management information of the VOB corresponding to the corresponding playlist and the playlist, and the AV data to be processed by the presentation processing unit (208). Instruct to play. Also, the management information processing unit (207) receives the reference time information from the presentation processing unit (208), instructs the presentation processing unit (208) to stop AV data reproduction based on the time information, and the program processing unit An event indicating the program execution timing is generated for (206).

  The presentation processing unit (208) has a decoder corresponding to each of video, audio, and subtitle / image (still image), and decodes and outputs AV data in accordance with an instruction from the management information processing unit (207). In the case of video data and subtitles / images, after decoding, the video data and subtitles / images are drawn on the dedicated plane, video plane (210) and image plane (209), and the video is synthesized by the synthesis processing unit (211). Output to the device.

  In this way, as shown in FIG. 3, the BD player has a device configuration based on the data configuration recorded on the BD disc shown in FIG.

  FIG. 4 is a detailed block diagram of the player configuration described above. In FIG. 7, the AV recording memory (205) is in the image memory (308) and the track buffer (309), the program processing unit (206) is in the program processor (302) and the UOP manager (303), and the management information processing unit (207). ) Is a scenario processor (305) and a presentation controller (306), and a presentation processing unit (208) is a clock (307), a demultiplexer (310), an image processor (311), a video processor (312) and a sound processor (313). Are corresponding to each.

  The VOB data (MPEG stream) read from the BD disc (201) is recorded in the track buffer (309), and the image data (PNG) is recorded in the image memory (308). The demultiplexer (310) extracts the VOB data recorded in the track buffer (309) based on the time of the clock (307), and sends the video data to the video processor (312) and the audio data to the sound processor (313). The video processor (312) and the sound processor (313) are each composed of a decoder buffer and a decoder as defined by the MPEG system standard. That is, the video and audio data sent from the demultiplexer (310) are temporarily recorded in the respective decoder buffers and decoded by the individual decoders according to the clock (307).

The PNG recorded in the image memory (308) has the following two processing methods.
If the image data is for subtitles, the presentation controller (306) instructs the decoding timing. In order for the scenario processor (305) to receive the time information from the clock (307) once and display the appropriate subtitles, the subtitles are displayed to the presentation controller (306) at the subtitle display time (start and end). Give hidden instructions. The image processor (311) that has received the decode / display instruction from the presentation controller (306) extracts the corresponding PNG data from the image memory (308), decodes it, and draws it on the image plane (314).

  Next, when the image data is for a menu, the program processor (302) instructs the decoding timing. The time when the program processor (302) instructs to decode the image depends on the BD program being processed by the program processor (302), and is not generally determined.

  As described with reference to FIG. 6, the image data and the video data are output to the image plane (314) and the video plane (315) after decoding, respectively, and are output after being combined by the combining processing unit (316).

  The management information (scenario, AV management information) read from the BD disc (201) is stored in the management information recording memory (304), but the scenario information ("BD.INFO" and "XXX.PL") is stored in the management information recording memory (304). It is read into the scenario processor (305). The AV management information (“YYY.VOBI”) is read and processed by the presentation controller (306).

  The scenario processor (305) analyzes the information of the playlist, and instructs the presentation controller (306) the VOB referenced by the playlist and the playback position thereof. The presentation controller (306) manages the management information of the target VOB. ("YYY.VOBI") is analyzed, and an instruction is issued to the drive controller (317) to read out the target VOB.

  The drive controller (317) moves the optical pickup according to the instruction of the presentation controller (306), and reads the target AV data. The read AV data is read to the image memory (308) or the track buffer (309) as described above.

  The scenario processor (305) monitors the time of the clock (307) and throws an event to the program processor (302) at the timing set in the management information.

  The BD program (“BD.PROG” or “XXX.PROG”) recorded in the program recording memory (301) is executed by the program processor 302. The program processor (302) processes the BD program when an event is sent from the scenario processor (305) or when an event is sent from the UOP manager (303). The UOP manager (303) generates an event for the program processor (302) when a request is sent from the user by a remote control key.

(Application space)
FIG. 5 shows a BD application space.

  In the application space of the BD, a play list (PlayList) is one playback unit. A playlist is a concatenation of cells (Cell) and has a static scenario that is a reproduction sequence determined by the order of concatenation and a dynamic scenario described by a program. Unless there is a dynamic scenario by the program, the playlist only reproduces the individual cells in order, and the reproduction of the playlist ends when the reproduction of all the cells is completed. On the other hand, the program can dynamically change the playback target depending on the playback description beyond the playlist, the user selection, or the player status. A typical example is a menu. In the case of BD, a menu can be defined as a scenario to be played back by user selection, and is to dynamically select a playlist by a program.

  The program referred to here is an event handler executed by a time event or a user event.

  The time event is an event generated based on time information embedded in the playlist. The event sent from the scenario processor (305) described in FIG. 4 to the program processor (302) corresponds to this. When a time event is issued, the program processor (302) executes an event handler associated with the ID. As described above, the program to be executed can instruct playback of another playlist. In this case, playback of the currently played playlist is stopped and playback of the designated playlist is started. And transition.

  A user event is an event generated by a user's remote control key operation. User events are roughly divided into two types. The first is a menu selection event generated by operating a cursor key ("Up", "Down", "Left", "Right" key) or a "Determination" key. The event handler corresponding to the event selected from the menu is valid only for a limited period in the playlist (the validity period of each event handler is set as playlist information). A valid event handler is searched when the “down”, “left”, “right” key, or “decision” key is pressed. If there is a valid event handler, the event handler is executed. In other cases, menu selection events will be ignored.

  The second user event is a menu call event generated by operating the “menu” key. When a menu call event is generated, a global event handler is called. A global event handler does not depend on a playlist and is always an effective event handler. By using this function, it is possible to implement a DVD menu call (such as a function for calling a voice or subtitle menu during title reproduction and executing title reproduction from a point where the voice or subtitle was interrupted after the change).

  A cell (Cell), which is a unit constituting a static scenario in a playlist, refers to all or part of a playback section of a VOB (MPEG stream). The cell has a playback section in the VOB as start and end time information. The VOB management information (VOBI) paired with each VOB has a time map (Time Map or TMAP) which is a table information of recording addresses corresponding to the reproduction time of the data in the VOB management information (VOBI). It is possible to derive the read start address and end address in the VOB (that is, in the target file “YYY.VOB”) with the above-described VOB playback and end time using the map. Details of the time map will be described later.

(Details of VOB)
FIG. 6 is a configuration diagram of an MPEG stream (VOB) used in this embodiment.

  As shown in FIG. 6, the VOB is composed of a plurality of VOBUs (Video Object Units). The VOBU is one playback unit as a multiplexed stream including audio data on the basis of GOP (Group Of Pictures) referred to as an MPEG video stream. A VOBU has a video playback time of 1.0 seconds or less, and usually has a playback time of about 0.5 seconds.

  The TS packet (MPEG-2 Transport Stream Packet) at the head of the VOBU stores a sequence header, a subsequent GOP header, and an I picture (Intra-coded), so that decoding from the I picture can be started. Yes. Also, the address (start address) of the TS packet including the head of the I picture at the head of this VOBU, the address (end address) from this start address to the TS packet including the end of the I picture, and the playback start time of this I picture (PTS) is managed by a time map. Therefore, a time map entry is given for each TS packet at the head of the VOBU.

  The VOBU has a video packet (V_PKT) and an audio packet (A_PKT) therein. Each packet is 188 bytes, and although not shown in FIG. 6, immediately before each TS packet, an ATS (Arrival Time Stamp) that is a relative decoder supply start time of the TS packet is given. .

  The reason why ATS is assigned to each TS packet is that the system rate of this TS stream is not a fixed rate but a variable rate. In general, when the system rate is fixed, a dummy TS packet called a NULL packet is inserted, but a variable rate is suitable for recording with high image quality within a limited recording capacity. In BD, it is recorded as a TS stream with ATS.

FIG. 7 is a diagram showing the structure of a TS packet.
As shown in FIG. 7, the TS packet includes a TS packet header, an application field, and a payload portion. The TS packet header stores a PID (Packet Identifier), thereby identifying what information the TS packet stores. The application field stores PCR (Program Clock Reference). PCR is a reference value of a standard clock (referred to as System Time Clock, STC) of a device that decodes a stream. The device typically demultiplexes the system stream at the timing of PCR and reconstructs various streams such as a video stream. A PES packet is stored in the payload.

  In the PES packet header, DTS (Decoding Time Stamp) and PTS (Presentation Time Stamp) are stored. DTS indicates the decoding timing of the picture / audio frame stored in the PES packet, and PTS indicates the presentation timing such as video / audio output. Elementary data such as video data and audio data is sequentially put into a data storage area of a packet (PES Packet) called a PES packet payload from the head. In the PES packet header, an ID (stream_id) for identifying which stream is the data stored in the payload is also recorded.

  Details of the TS stream are defined in ISO / IEC13818-1, and a characteristic of BD is that an ATS is assigned to each TS packet.

(VOB interleaved recording)
Next, interleaved recording of a VOB file will be described with reference to FIGS.

  The upper part of FIG. 8 is a part of the player configuration diagram described above. As shown in the figure, the data on the BD disc is input to the track buffer if it is a VOB or MPEG stream through the optical pickup, and is input to the image memory if it is PNG or image data.

  The track buffer is a FIFO, and the input VOB data is sent to the demultiplexer in the input order. At this time, individual TS packets are extracted from the track buffer according to the ATS described above, and data is sent to the video processor or sound processor via the demultiplexer. On the other hand, in the case of image data, the presentation controller instructs which image to draw. The image data used for drawing is deleted from the image memory at the same time in the case of subtitle image data, but in the case of menu image data, it remains in the image memory during the menu drawing. This is because the menu drawing depends on the user's operation, and part of the menu may be redisplayed or replaced with a different image following the user's operation, and the image data of the redisplayed part will be decoded. This is to make it easier.

  The lower part of FIG. 8 is a diagram showing interleaved recording of a VOB file and a PNG file on a BD disc. In general, in the case of a ROM such as a CD-ROM or a DVD-ROM, AV data serving as a series of continuous reproduction units is continuously recorded. As long as continuous recording is performed, the drive only needs to read the data sequentially and send it to the decoder. However, if the continuous data is divided and discretely arranged on the disk, seek is performed between individual continuous sections. This is because an operation is entered, and during this time, reading of data is stopped, and supply of data may be stopped. Similarly, in the case of a BD, it is desirable that a VOB file can be recorded in a continuous area. However, for example, there is data that is reproduced in synchronization with video data recorded in the VOB, such as caption data, and the VOB file Similarly, it is necessary to read the caption data from the BD disc by some method.

  As one method of reading subtitle data, there is a method of reading subtitle image data (PNG file) all at once before the start of VOB reproduction. However, in this case, a large amount of memory is required, which is unrealistic.

  Therefore, a method is used in which the VOB file is divided into several blocks and interleaved with image data. The lower part of FIG. 8 illustrates the interleave recording.

  By appropriately interleaving the VOB file and the image data, it becomes possible to store the image data in the image memory at a necessary timing without the large amount of temporary recording memory as described above. However, when reading the image data, the reading of the VOB data is naturally stopped.

  FIG. 9 is a diagram for explaining a VOB data continuous supply model using a track buffer that solves this problem.

  As described above, VOB data is temporarily stored in the track buffer. When a difference (Va> Vb) is provided between the data input rate (Va) to the track buffer and the data output rate (Vb) from the track buffer, as long as data is continuously read from the BD disc, the data storage in the track buffer The amount will increase.

  As shown in the upper part of FIG. 9, it is assumed that a continuous recording area of VOB continues from “a1” to “a2” of logical addresses. It is assumed that between “a2” and “a3” is an interval in which image data is recorded and VOB data cannot be read.

The lower part of FIG. 9 shows the inside of the track buffer. The horizontal axis indicates time, and the vertical axis indicates the amount of data stored in the track buffer. Time “t1” indicates the time when reading of “a1”, which is the starting point of one continuous recording area of the VOB, is started. After this time, data is accumulated in the track buffer at the rate Va-Vb. Needless to say, this rate is the difference between the input and output rates of the track buffer. The time “t2” is the time when the data “a2”, which is the end point of one continuous recording area, is read. That is, the amount of data in the track buffer increases from time “t1” to “t2” at the rate Va−Vb, and the data accumulation amount at time “t2” can be obtained by the following equation. .

B (t2) = (Va−Vb) × (t2−t1) (Formula 1)

After this, since the image data continues until the address “a3” on the BD disc, the input to the track buffer becomes 0, and the data amount in the track buffer decreases at the output rate “−Vb”. Become. This is up to the read position “a3” and “t3” in time.

  What is important here is that if the amount of data stored in the track buffer before time “t3” becomes zero, there is no VOB data to be supplied to the decoder, and there is a possibility that VOB reproduction stops. There is. However, if data remains in the track buffer at time “t3”, this means that VOB playback can be continued without stopping.

This condition can be expressed by the following equation.

B (t2) ≧ −Vb × (t3−t2) (Formula 2)

That is, the arrangement of the image data (non-VOB data) should be determined so as to satisfy Expression 2.

(Navigation data structure)
The structure of BD navigation data (BD management information) will be described with reference to FIGS.

  FIG. 10 shows the internal structure of the VOB management information information file (“YYY.VOBI”).

  The VOB management information includes stream attribute information (Attribute) of the VOB and a time map. Each stream attribute has a video attribute (Video) and an audio attribute (Audio # 0 to Audio # m). Particularly in the case of an audio stream, since a VOB can have a plurality of audio streams at the same time, the presence or absence of a data field is indicated by the number of audio streams (Number).

The following are the fields that the video attribute (Video) has and the values that each can have.
Compression method (Coding):
MPEG1
MPEG2
MPEG4
MPEG4-AVC (Advanced Video Coding)
Resolution:
1920x1080
1440x1080
1280x720
720x480
720x565
Aspect ratio (Aspect)
4: 3
16: 9
Frame rate
60
59.94 (60 / 1.001)
50
30
29.97 (30 / 1.001)
25
24
23.976 (24 / 1.001)

The following are the fields that the audio attribute (Audio) has and the values that each can have.
Compression method (Coding):
AC3
MPEG1
MPEG2
LPCM
Number of channels (Ch):
1-8
Language attribute:

  The time map (TMAP) is a table having information for each VOBU, and has the number of VOBUs (Number) possessed by the VOB and each VOBU information (VOBU # 1 to VOBU # n). Each VOBU information is composed of an address I_start of a VOBU first TS packet (I picture start), an offset address (I_end) up to the end address of the I picture, and a reproduction start time (PTS) of the I picture.

  Note that the value of I_end does not have an offset value, that is, the size of the I picture, but may have the actual end address of the I picture.

FIG. 11 is a diagram for explaining the details of the VOBU information.
As is widely known, an MPEG video stream may be compressed at a variable bit rate for high-quality recording, and there is no simple correlation between playback time and data size. Conversely, since AC3, which is a voice compression standard, performs compression at a fixed bit rate, the relationship between time and address can be obtained by a linear expression. However, in the case of MPEG video data, each frame has a fixed display time, for example, in the case of NTSC, one frame has a display time of 1 / 29.97 seconds, but the data size after compression of each frame is picture size. The data size varies greatly depending on the characteristics and the picture type used for compression, so-called I / P / B picture. Therefore, in the case of MPEG video, the relationship between time and address cannot be expressed in a linear form.

  Naturally, an MPEG system stream in which MPEG video data is multiplexed, that is, VOB, cannot express time and data size in a linear form. For this reason, the time map (TMAP) links the relationship between time and address in the VOB.

  In this way, when given time information is provided, first, the VOBU to which the time belongs is searched (following the PTS for each VOBU), and the VOBU having the PTS immediately before the time is stored in the VOBU. Jumping in (address specified by I_start), decoding starts from the I picture at the head of the VOBU, and display starts from the picture at that time.

Next, the internal structure of the playlist information (“XXX.PL”) will be described with reference to FIG.
The playlist information includes a cell list (CellList) and an event list (EventList).

  The cell list (CellList) is a reproduction cell sequence in the playlist, and the cells are reproduced in the description order of the list. The contents of the cell list (CellList) are the number of cells (Number) and cell information (Cell # 1 to Cell # n).

  The cell information (Cell #) has a VOB file name (VOBName), a start time (In) and an end time (Out) in the VOB, and a caption table (SubtitleTable). The start time (In) and the end time (Out) are each expressed by a frame number in the VOB, and the address of VOB data necessary for reproduction can be obtained by using the time map described above.

  The caption table (SubtitleTable) is a table having caption information that is reproduced in synchronization with the VOB. Subtitles can have multiple languages as well as audio, and the first information of the subtitle table (SubtitleTable) consists of the number of languages (Number) followed by tables for each language (Language # 1 to Language # k). Yes.

  Each language table (Language #) includes language information (Language), the number of subtitle information displayed individually (Number), and subtitle information displayed individually (Speech # 1 to Speech # j). The caption information (Speech #) is composed of the corresponding image data file name (Name), caption display start time (In) and caption display end time (Out), and caption display position (Position). .

  The event list (EventList) is a table that defines events that occur in the play list. The event list is made up of individual events (Event # 1 to Event # m) following the number of events (Number), and each event (Event #) includes an event type (Type) and an event ID (ID). , The event occurrence time (Time) and the effective period (Duration).

  FIG. 13 is an event handler table (“XXX.PROG”) having event handlers (time events and user events for menu selection) for each playlist.

  The event handler table has a defined number of event handlers / programs (Number) and individual event handlers / programs (Program # 1 to Program # n). The description in each event handler / program (Program #) has the event handler ID (ID) paired with the event handler start definition (<event_handler> tag) and the above-mentioned event ID. It is described between parentheses “{” and “}” following the Function. The events (Event # 1 to Event # m) stored in the event list (EventList) of “XXX.PL” are specified using the ID (ID) of the event handler of “XXX.PROG”.

  Next, the internal structure of information relating to the entire BD disc (“BD.INFO”) will be described with reference to FIG.

  The entire BD disc information includes a title list (TitleList) and an event table for global events (EventList).

  The title list (TitleList) is composed of the number of titles (Number) in the disc and the following pieces of title information (Title # 1 to Title # n). Each title information (Title #) includes a playlist table (PLTable) included in the title and a chapter list (ChapterList) in the title. The playlist table (PLTable) has the number of playlists in the title (Number) and the playlist name (Name), that is, the playlist file name.

  The chapter list (ChapterList) is composed of the number of chapters (Number) included in the title and individual chapter information (Chapter # 1 to Chapter # n), and each chapter information (Chapter #) is the cell of the chapter. It has a table (CellTable), and the cell table (CellTable) is composed of the number of cells (Number) and entry information (CellEntry # 1 to CellEntry # k) of each cell. Cell entry information (CellEntry #) is described by the name of the playlist including the cell and the cell number in the playlist.

  The event list (EventList) includes the number of global events (Number) and information on individual global events. It should be noted that the global event defined first is called a first event (FirstEvent), and is the first event called when a BD disc is inserted into a player. The event information for global events has only an event type (Type) and an event ID (ID).

  FIG. 15 is a table (“BD.PROG”) of the global event handler program.

  This table has the same contents as the event handler table described in FIG.

(Event generation mechanism)
The event generation mechanism will be described with reference to FIGS.

FIG. 16 is an example of a time event.
As described above, a time event is defined by an event list (EventList) of playlist information (“XXX.PL”). When an event defined as a time event, that is, when the event type (Type) is “TimeEvent”, the time event having the ID “Ex1” is transferred from the scenario processor to the program processor when the event generation time (“t1”) is reached. Against. The program processor searches for an event handler having the event ID “Ex1” and executes the target event handler. For example, in this embodiment, two button images can be drawn.

FIG. 17 shows an example of a user event for performing a menu operation.
As described above, the user event for performing the menu operation is also defined in the event list (EventList) of the playlist information (“XXX.PL”). When an event defined as a user event, ie, an event type (Type) is “UserEvent”, the user event becomes ready when the event generation time (“t1”) is reached. At this time, the event itself has not yet been generated. The event is in a ready state for the period indicated by the valid period information (Duration).

  As illustrated in FIG. 17, when the user presses the “up”, “down”, “left”, “right”, or “decision” keys of the remote control key, a UOP event is first generated by the UOP manager and raised to the program processor. The program processor sends a UOP event to the scenario processor. The scenario processor searches for a valid user event at the time when the UOP event is received. If there is a target user event, the user event is Generate and lift to the program processor. The program processor searches for an event handler having the event ID “Ev1” and executes the target event handler. For example, in the case of the present embodiment, reproduction of playlist # 2 is started.

  The generated user event does not include information on which remote control key is pressed by the user. Information on the selected remote control key is transmitted to the program processor by a UOP event, and is recorded and held in the register SPRM (8) of the virtual player. The event handler program can check the value of this register and execute branch processing.

FIG. 18 shows an example of a global event.
As described above, a global event is defined by an event list (EventList) of information (“BD. INFO”) relating to the entire BD disc. When an event defined as a global event, that is, an event type (Type) is “GlobalEvent”, an event is generated only when a user operates a remote control key.

  When the user presses “Menu”, a UOP event is first generated by the UOP manager and raised to the program processor. The program processor sends a UOP event to the scenario processor, and the scenario processor generates a corresponding global event and sends it to the program processor. The program processor searches for an event handler having the event ID “menu” and executes the target event handler. For example, in the case of the present embodiment, reproduction of playlist # 3 is started.

  In this embodiment, it is simply called a “menu” key, but there may be a plurality of menu keys as in a DVD. It is possible to cope by defining IDs corresponding to the respective menu keys.

(Virtual player machine)
The functional configuration of the program processor will be described with reference to FIG.

  The program processor is a processing module having a virtual player machine inside. The virtual player machine is a functional model defined as a BD and does not depend on the implementation of each BD player. That is, it is guaranteed that the same function can be executed in any BD player.

  The virtual player machine has two functions. Programming functions and player variables (registers). The programming function is based on Java (registered trademark) Script, and the following two functions are defined as BD specific functions.

Link function: Stops the current playback and starts playback from the specified playlist, cell, and time Link (PL #, Cell #, time)
PL #: Playlist name Cell #: Cell number time: Playback start time in the cell PNG drawing function: Draws specified PNG data on the image plane Draw (File, X, Y)
File: PNG file name X: X coordinate position Y: Y coordinate position Image plane clear function: Clear specified area of image plane Clear (X, Y, W, H)
X: X-coordinate position Y: Y-coordinate position W: X-direction width H: Y-direction width Player variables include a system parameter (SPRM) indicating the state of the player and a general parameter (GPRM) that can be used for general purposes.

FIG. 20 is a list of system parameters (SPRM).
SPRM (0): Language code SPRM (1): Audio stream number SPRM (2): Subtitle stream number SPRM (3): Angle number SPRM (4): Title number SPRM (5): Chapter number SPRM (6): Program Number SPRM (7): Cell number SPRM (8): Selection key information SPRM (9): Navigation timer SPRM (10): Playback time information SPRM (11): Karaoke mixing mode SPRM (12): Parental country information SPRM (13): Parental level SPRM (14): Player set value (video)
SPRM (15): Player setting value (audio)
SPRM (16): Audio stream language code SPRM (17): Audio stream language code (extended)
SPRM (18): Language code for subtitle stream SPRM (19): Language code for subtitle stream (extended)
SPRM (20): Player region code SPRM (21): Reserve SPRM (22): Reserve SPRM (23): Playback state SPRM (24): Reserve SPRM (25): Reserve SPRM (26): Reserve SPRM (27): Spare SPRM (28): Spare SPRM (29): Spare SPRM (30): Spare SPRM (31): Spare In this embodiment, the programming function of the virtual player is based on JavaScript, but is not based on JavaScript. Other programming functions such as B-Shell and Perl Script used in the registered OS can be used. In other words, the present invention is not limited to JavaScript.

(Program example)
21 and 22 show examples of programs in event handlers.

FIG. 21 shows an example of a menu having two selection buttons.
The program on the left side of FIG. 24 is executed using the time event at the head of the cell (PlayList # 1.Cell # 1). Here, “1” is first set to GPRM (0), one of the general parameters. GPRM (0) is used to identify the selected button in the program. In the initial state, the initial value is that the button 1 arranged on the left side is selected.

  Next, PNG drawing is performed for each of the buttons 1 and 2 by using a drawing function Draw. The button 1 draws the PNG image “1black.png” with the coordinates (10, 200) as the starting point (left end). The button 2 draws a PNG image “2white.png” with the coordinates (330, 200) as a starting point (left end).

  At the end of this cell, the program on the right side of FIG. 24 is executed using a time event. Here, it is specified to play again from the beginning of the cell using the Link function.

FIG. 22 shows an example of an event handler for a user event for menu selection.
When the remote control key of “Left” key, “Right” key, or “Determination” key is pressed, a corresponding program is written in the event handler. When the user presses the remote control key, as described with reference to FIG. 17, a user event is generated and the event handler of FIG. 22 is activated. In this event handler, branch processing is performed using the value of GPRM (0) identifying the selection button and SPRM (8) identifying the selected remote control key.

Condition 1) When button 1 is selected and the selection key is the “right” key GPRM (0) is reset to 2, and the button in the selected state is changed to right button 2.
Rewrite the images of Button 1 and Button 2, respectively.
Condition 2) When the selection key is “OK (OK)” and the button 1 is selected. Play of the playlist # 2 is started. Condition 3) When the selection key is “OK (OK)” and the button is selected. When 2 is selected Start playback of playlist # 3. The execution process is performed as described above.

(Player processing flow)
Next, the processing flow in the player will be described with reference to FIGS.

FIG. 23 is a basic processing flow up to AV playback.
When the BD disc is inserted (S101), the BD player receives the BD. Reading and analysis of INFO file (S102), BD. PROG reading (S103) is executed. BD. INFO and BD. Both PROGs are temporarily stored in the management information recording memory and analyzed by the scenario processor.

  Subsequently, the scenario processor is BD. The first event is generated according to the first event (FirstEvent) information in the INFO file (S104). The generated first event is received by the program processor, and an event handler corresponding to the event is executed (S105).

  It is expected that playlist information to be reproduced first is recorded in the event handler corresponding to the first event. If play list reproduction is not instructed, the player does not reproduce anything and simply waits for acceptance of a user event. (S201). When the BD player receives a remote control operation from the user, the UOP manager raises a UOP event to the program manager (S202).

  The program manager determines whether the UOP event is a menu key (S203). If the UOP event is a menu key, it sends a UOP event to the scenario processor, and the scenario processor generates a user event (S204). The program processor executes an event handler corresponding to the generated user event (S205).

FIG. 24 is a processing flow from the start of PL playback to the start of VOB playback.
As described above, play list reproduction is started by the first event handler or the global event handler (S301). The scenario processor reads and analyzes playlist information “XXX.PL” as information necessary for playback of the playlist to be played back (S302), and reads program information “XXX.PROG” corresponding to the playlist (S303). ). Subsequently, the scenario processor instructs the reproduction of the cell based on the cell information registered in the playlist (S304). Cell playback means that a request is sent from the scenario processor to the presentation controller, and the presentation controller starts AV playback (S305).

  When the start of AV playback (S401) is started, the presentation controller reads and analyzes the VOB information file (XXX.VOBI) corresponding to the cell to be played back (S402). The presentation controller uses the time map to specify the VOBU to start playback and its address, and instructs the drive controller to specify the read address. The drive controller reads the target VOB data (S403), and the VOB data is sent to the decoder. Playback is started (S404).

  The VOB playback is continued until the playback section of the VOB ends (S405), and when it ends, the process proceeds to the next cell playback S304. Next, if there is no cell, playback stops (S406).

FIG. 25 is an event processing flow after the start of AV playback.
The BD player is an event-driven player model. When playback of the playlist is started, event processing processes for the time event system, the user event system, and the caption display system are started, and the event processing is executed in parallel.

The S500 system processing is a time event system processing flow.
After the play list reproduction is started (S501), the scenario processor confirms whether or not the time event occurrence time is reached (S503) through a step (S502) for confirming whether the play list reproduction is completed. If the time event occurrence time is reached, the scenario processor generates a time event (S504), and the program processor receives the time event and executes the event handler (S505).

  If the time event occurrence time is not reached in step S503, or after the event handler execution process in step S504, the process returns to step S502 again, and the above-described process is repeated. Also, when it is confirmed in step S502 that the play list reproduction has been completed, the time event processing is forcibly terminated.

The S600 system processing is a user event system processing flow.
After the play list reproduction is started (S601), the play list reproduction end confirmation step (S602) is performed, and then the process proceeds to the UOP reception confirmation step (S603). When the UOP is accepted, the UOP manager generates a UOP event (S604), and the program processor that receives the UOP event checks whether the UOP event is a menu call (S605). The program processor causes the scenario processor to generate an event (S607), and the program processor executes the event handler (S608).

  If it is determined in step S605 that the UOP event is not a menu call, it indicates that the UOP event is an event by a cursor key or a “decision” key. In this case, the scenario processor determines whether the current time is within the user event valid period (S606), and if it is within the valid period, the scenario processor generates a user event (S607) and the program processor is targeted. The event handler is executed (S608).

  If no UOP is accepted in step S603, if the current time is not in the user event valid period in step S606, or after the event handler execution process in step S608, the process returns to step S602 again to repeat the above-described process. Further, when it is confirmed in step S602 that the play list reproduction has ended, the user event processing is forcibly ended.

FIG. 26 is a flowchart of caption processing.
After the play list reproduction is started (S701), the play list reproduction end confirmation step (S702) is followed by the subtitle drawing start time confirmation step (S703). In the case of the caption rendering start time, the scenario processor instructs the presentation controller to render captions, and the presentation controller instructs the image processor to render captions (S704). If it is determined in step S703 that it is not the caption drawing start time, it is confirmed whether it is the caption display end time (S705). If it is determined that the subtitle display end time is reached, the presentation controller instructs the image processor to delete the subtitle and deletes the drawn subtitle from the image plane (S706).

  After the caption drawing step S704 ends, after the caption erasure step S706 ends, or when it is determined that the time is not the same at the caption display end time confirmation step S705, the process returns to step S702 and the above-described processing is repeated. Also, when it is confirmed in step S702 that the playlist reproduction has been completed, the caption display processing is forcibly terminated.

(Embodiment 2)
In this embodiment, when P / I pictures are used, the playback quality during special playback is improved by restricting the stream and management information. Hereinafter, restrictions on multiplexing the encoded stream will be described.

  First, the relationship between the time map and the encoded stream will be described. From the time map, a position that can be selected as a playback start point and a picture that can be read during special playback can be indicated. The time map of the present invention does not select a RAU starting from a P / I picture as a position that can be selected as a playback start point or a point that can be read during special playback.

  FIG. 30 shows the relationship between the time map and the RAU. The playback start point and the position of the RAU head picture read at the time of special playback are stored in the time map in association with time as shown in FIG. When the time is specified, the time map is used to determine the address to start playback, and seek is performed to start playback. At this time, the P / I picture is not registered in the time map because it is not appropriate as a playback start position or a picture read at the time of special playback. By doing so, it is possible to avoid starting playback from an image whose resolution has been reduced to half, without being selected at the playback start point or special playback.

  In addition, as one of the attribute information of the time map, there may be a flag that guarantees that no P / I picture exists in the stream. If this flag is valid, there is no P / I picture, so playback may be started from any RAU head.

  Further, as one of the attribute information of the time map, there may be a flag for guaranteeing that the time map does not point to the P / I picture. If this flag is valid, the time map does not point to a P / I picture, and therefore playback may be started from the RAU head position registered in the time map.

  If either of these two pieces of attribute information is present, the player can acquire information on the reproduction start position at which reproduction can be started with sufficient resolution, by simply referring to the time map without analyzing the stream. .

  FIG. 31 shows an example in which attribute information is added to the time map so that the picture type of the picture pointed to by the time map can be registered. If the picture type is known in this way, the player can also decide not to select a P / I picture as the playback start position, so this method is also effective.

  As shown in FIG. 32, in the P / I picture, when the P picture in the first field refers to the I picture in the second field, the first frame can be decoded. Different from the P / I picture described above, in this case, it may be selected as a picture that can be displayed at the playback start point or special playback.

Hereinafter, another example of the restriction method will be described.
At stream connection points or angle switching points, it is important that playback images can be seamlessly connected before and after switching. Therefore, in order to realize a seamless connection, it is effective to prohibit the P / I picture as the first picture after switching, and the following is possible.

1. 1. Do not point to a P / I picture from the time map. In the stream, the top of the RAU is not a P / I picture.

  The time map stores a flag indicating whether or not the current play item and the immediately preceding play item can be seamlessly connected. Therefore, in a play item that can be seamlessly connected by the flag, the P / I picture may not be arranged as the first picture of the play item. In the time map, the play item can indicate information on one or more angles, and a flag indicating whether or not the angle can be switched seamlessly can be stored. Therefore, when it is indicated that seamless angle switching is possible, the P / I picture may not be arranged as the first picture of each angle. Alternatively, at the point of angle switching, a P / I picture may be prohibited as the first picture after the angle switching regardless of whether the angle is seamless. In addition, since a flag indicating whether or not random access reproduction of each play item is permitted by the content creator is stored, when random access is permitted, a P / I picture is added at the head of the play item. You may decide not to arrange. In the example of FIG. 33, if the flag indicating that seamless connection is possible is set, the first picture of the play item is an I / I picture or only an I / P picture. If the flag is not set, P / Indicates that the I picture may be the head of the play item.

  Note that this method is not limited to P / I pictures, and can be used in all cases where the decoding of the leading RAU picture cannot be guaranteed. Note that the information indicating whether or not the connection can be seamless may indicate the relationship between the current play item and the immediately following play item, or may be information on all the play items indicated by the playlist.

  Next, an example of restricting within a VC-1 stream without combining with a time map will be described. Since it is desirable that the presence / absence of a P / I picture can be determined before decoding of a picture in the RAU is started, information indicating whether or not the leading picture of the RAU is a P / I picture is stored at the leading edge of the RAU. As described above, there are two types of VC-1 RAUs, a closed GOP type and an open GOP type. The type of RAU is indicated by a flag in the header of the entry point. If the flag is set, it is a closed GOP type, and if it is not set, it is an open GOP type. In seamless connection, multi-angle playback, and the like, since playback is generally started from a closed GOP type RAU, the top picture of the closed RAU is not set as a P / I picture. At this time, a flag indicating whether or not the RAU is a closed GOP type can be used as a flag indicating whether or not the leading picture of the RAU is a P / I picture. Therefore, as shown in FIG. 34, when the entry point header indicates that it is a closed GOP type RAU, the P / I picture is prohibited as the first picture of the RAU, and the RAU is an open GOP type RAU. Is indicated, a P / I picture can be used as the leading picture of the RAU. Information indicating whether or not the head of the RAU is a P / I picture may be separately stored using user data or the like.

  Furthermore, by using a combination of time map information and information in the stream, the following four types of information can be shown as attributes of a random access unit.

1. 1. It is a closed GOP type RAU, and the first picture of the RAU is not a P / I picture. 2. It is a closed GOP type RAU, and the first picture of the RAU may be a P / I picture. 3. It is an open GOP type RAU, and the first picture of the RAU is not a P / I picture. It is an open GOP type RAU, and the first picture of the RAU may be a P / I picture

  For example, (a flag indicating whether or not the GOP is a closed GOP in the stream, a flag indicating whether or not seamless connection is possible in the time map) = (1, 1), (1, 0), (0, 1), ( Assume that the combinations of (0, 0) indicate 1, 2, 3, and 4, respectively. In this way, any one of the above-described attributes can be selected and used according to the pattern important by the application, such as high-speed playback of only I pictures, jump-in playback, seamless connection, or multi-angle playback. Specifically, if 1 and 3 or 4 are selected, there is no restriction on the arrangement of the I / P picture in the open GOP type RAU, and the I / P picture in the closed GOP type RAU. Will not be placed at the beginning. Note that three types of the above 1 and 2 and an open GOP type RAU may be defined.

  Further, whether or not the P / I picture can be used may be switched according to the bit rate of the stream. The P / I picture is effective when a scene change occurs in the second field in the frame, and particularly effective at a low bit rate. Therefore, the P / I picture may be usable only when the bit rate indicated by the VC-1 stream or the management information is equal to or less than a predetermined value. The bit rate can be indicated in the sequence layer. Furthermore, the bit rate may be indicated in user data such as an entry point level. Here, if there is information indicating that the head of the RAU is a P / I picture without directly indicating the bit rate in the user data, the bit rate of the corresponding RAU or the entire stream is equal to or less than a predetermined value, Or it may be less. Here, the maximum bit rate is desirable in terms of setting the upper limit value of the processing capability of the playback device, but it may be an average bit rate. In the VC-1 standard, a plurality of levels are provided, and a bit rate and a buffer size necessary for decoding are defined for each level. Therefore, whether or not the P / I picture can be used may be switched according to the level. The level is indicated by a sequence layer or the like.

  The above restriction methods may be used in combination. For example, when the bit rate is a predetermined value or less, the P / I picture can be used only in the open GOP type RAU. Also good. It is desirable that the closed GOP type RAU can be reproduced from the first picture of the GOP without degrading the image quality. However, in the open GOP type RAU, there may be a picture that cannot be decoded originally at the time of random access. This is because there is a large tolerance for an increase in the number of pictures that cannot be decoded by the presence of.

  Note that when a VC-1 stream is used in a specific application such as a BD or HD-DVD, it may be prohibited to set the head of the RAU to a P / I picture. At this time, in the case of a BD-ROM, the type of application is indicated by whether or not a directory with a specific name such as BD-INFO exists. Further, the availability of the P / I picture may be switched according to whether the VC-1 stream is the main content or additional content such as a bonus video. In general, since the additional content has a low bit rate and the P / I picture is effective, the P / I picture can be used, and the use of the P / I picture is prohibited in the main content having a high bit rate. Here, whether the content is main content or additional content is indicated by a flag in the BD management information. Alternatively, content stored in a location different from the optical disk such as a hard disk via a network can be regarded as additional content.

  Also, the encoded stream is not limited to VC-1, and can be applied to any encoding scheme that can use a field pair in which the first field is a P picture and the second field is an I picture.

(Embodiment 3)
FIG. 38 is a flowchart of the encoding method of the present invention for encoding a VC-1 stream according to the second embodiment, and is a step of restricting a P / I picture from being placed at the head in a closed GOP type RAU. It differs from the conventional encoding method in that step S1103 to step S1103 are newly provided.

  First, in step S1101, it is determined whether the picture to be encoded is the leading picture of the RAU. If it is the leading picture, the process proceeds to step S1102, and if not, the process proceeds to step S1104. In step S1103, it is determined whether the RAU is a closed GOP type. If the RAU is a closed GOP type, the process proceeds to step S1103, and if not, the process proceeds to step S1104. In step S1103, when a picture is encoded as a field, it is determined that an I / I picture or an I / P picture is used and no P / I picture is used. Subsequently, in step S1104, the pictures constituting the RAU are encoded based on the determination in step S1103. If the RAU is a closed GOP type, a flag indicating that the RAU is a closed GOP type is set. Note that step S1102 may be performed prior to step S1101.

  Further, a stream encoded by this encoding method may be multiplexed with audio or the like. As a multiplexing method, there is a method defined for each package medium such as an MPEG-2 transport stream or a BD (Blu-ray Disc).

  When multiplexing the output stream, when switching the angle in seamless connection multi-angle playback, a time map is used so that the connection picture or the first picture immediately after the change point does not become a P / I picture. create. Specifically, only a closed GOP type RAU may be specified as a connection point or a switching point.

  FIG. 39 is a block diagram showing a configuration of an image encoding device 10 that realizes the encoding method of the present embodiment. The image encoding device 10 differs from the conventional image encoding device 1 in that it includes a type restriction unit LIMIT that performs the processing from step S1101 to step S1103. The prediction structure determination unit PTYE determines the prediction structure of a picture based on the picture type restriction information LmtInf specified by the type restriction unit LIMIT.

(Embodiment 4)
FIG. 40 shows display during special playback such as multi-angle playback or continuous playback of different sections in the same stream in the image decoding method for decoding multiplexed data of a VC-1 stream according to the second embodiment. It is a flowchart which shows operation | movement. This image decoding method is different from the conventional image decoding method in that the operation from step S1001 to step S1004 for switching the picture display operation depending on whether or not the leading picture of the RAU is a P / I picture is unnecessary.

  Note that only when management information such as a time map enables multi-angle playback or when seamless connection is guaranteed, the display operation is not switched and the information cannot be identified from the management information. The display operation may be switched as in the conventional image decoding method.

  When the RAU is a closed GOP type, the display operation may be switched as in the conventional image decoding method without switching the display operation if it is an open GOP type.

  FIG. 41 is a block diagram illustrating a configuration of an image decoding device 30 that implements the decoding method according to the present embodiment. The image decoding apparatus 30 is different from the conventional image decoding apparatus in that it does not include the display switching unit ModeSet.

  Note that the moving picture coding scheme in each of the above embodiments is not limited to VC-1, and can be applied to all coding schemes having a similar prediction structure.

(Embodiment 5)
In the fifth embodiment, a data structure that realizes improved functionality of special playback such as random access playback and reverse playback by using a P / I picture will be described.

  First, the first problem in the conventional data structure will be described. FIG. 43 shows an example of the structure of a conventional RAU. In the example of FIG. 43, each picture is encoded with a field structure, and a P / I picture exists in the middle of the RAU. In the VC-1 standard, for a P / I picture that is the first picture of an RAU, a picture whose display order is later than the P / I picture is prohibited from referring to the P picture in the P / I picture. However, the restriction is not defined for P / I pictures in the middle of RAU. Therefore, as shown in FIG. 43, a picture subsequent to the P / I picture may refer to the P picture of the P / I picture. At this time, since the P picture of the P / I picture can refer to the forward P picture in the display order, it is necessary to decode from the leading picture of the RAU in order to decode the pictures after the P / I picture. Therefore, even when playback is started from a picture after the P / I picture by a user operation or the like, it is necessary to decode at least the I picture and the P picture from the head of the RAU pointed to as a random access point from the time map. is there. In particular, when the playback time length of the RAU is long and the number of pictures constituting the RAU increases, the number of pictures that need to be decoded in order to start playback from the jump position increases, and the delay and the processing amount increase. There are challenges.

  FIG. 44 shows a second problem of the conventional data structure. As described in the first to fourth embodiments, when the first picture of the RAU is a P / I picture, only the first frame or field pair of the RAU is reproduced to realize high-speed reproduction. Since reproduction quality deteriorates, it may be specified that a P / I picture is not arranged at the head of an RAU. Here, as shown in FIG. 44A, it is assumed that a scene change has occurred between the first field and the second field. In special playback, since it is desirable to be able to play back from the position where the scene change occurred, considering the division of the RAU, a P / I picture cannot be placed at the beginning of the RAU. Therefore, as shown in FIG. The leading picture of the RAU needs to be an I / I picture. As in this example, when a scene change occurs between the first field and the second field, the first field has a high correlation with the previous image in the display order. Encoding efficiency is improved when it is used. Therefore, there is a second problem that encoding efficiency is lowered by making the first picture an I / I picture.

  FIG. 45 shows an example of the RAU structure of the present embodiment. In the RAU of FIG. 45, the following restriction is provided for the prediction structure of the P / I picture in the middle of the RAU.

  A picture whose display order is later than the P / I picture does not refer to the P picture in the P / I picture.

  Thus, even when playback is started from a picture after the P / I picture by a user operation or the like, the picture after the P / I picture can be decoded by starting decoding from the I picture in the P / I picture. The effect of reducing the delay and processing amount during reproduction can be obtained. Also, in the case of performing reverse playback, it is not necessary to read and decode from the first picture of the RAU when playing back the picture after the P / I picture, and only the I picture of the P / I picture and the following pictures are not decoded. Since it is sufficient to read the data, it is possible to reduce the size of the buffer memory required for reverse reproduction or the number of times data is read into the buffer memory. Since the P / I picture is normally used when a scene change occurs between the first field and the second field, the picture after the P / I picture and the P picture in the P / I picture The correlation is low, and even if the reference to the P picture is restricted, the influence on the coding efficiency is negligible.

  FIG. 46 shows another example of the RAU structure of the present embodiment. In the example of FIG. 45, the position pointed to as the random access point in the time map and the RAU correspond one-on-one. On the other hand, in FIG. 46, there are a plurality of RAUs between the Nth and N + 1th random access points indicated by the time map. That is, there is an RAU that is not pointed out from the time map, and here, RAU2 is not pointed out from the time map. 46 divides the RAU of FIG. 45 into two RAUs, RAU1 and RAU2, and the leading picture of the RAU is a P / I picture. Here, when playback is started from a picture after the first P / I picture of RAU2, it is guaranteed that subsequent pictures in the RAU do not refer to the P picture of the first P / I picture. Decoding may be started from the I picture.

  In this way, a P / I picture can be used as a point for resetting the decoding operation during special reproduction. Further, the restriction that the picture after the P / I picture does not refer to the P picture of the P / I picture may be applied to all the P / I pictures in the RAU. In order to improve the P / I picture, it is sufficient to selectively restrict the P / I picture, and it is effective to add information indicating whether the restriction is applied to the P / I picture. This information may be stored in the encoded stream or may be stored in management information. FIG. 47 is an example in which information indicating whether or not the restriction that the picture after the P / I picture does not refer to the P picture of the P / I picture is applied is stored in the encoded stream. Here, the information is stored by map information called an RAU map. As shown in FIG. 47A, the RAU map is arranged before the picture data in the RAU. For example, VC-1 can be stored in entry / point level user data. Here, the RAU map in FIG. 47A shows information on the RAU in FIG. In the RAU of FIG. 47B, there are four P / I pictures in the RAU, and the reference relationship is restricted only for the second P / I picture. Therefore, the second P / I picture can be used as a point for resetting the decoding operation during special reproduction. Therefore, the RAU map does not guarantee that the reference relationship is restricted for the first, third, and fourth P / I pictures, and the reference relationship is restricted for the second P / I picture. It is shown that it is guaranteed that

  FIG. 54 shows an example of the syntax of the RAU map. FIG. 54A is a table showing a list of frame or field pair types constituting the RAU in decoding order. The definition of each parameter is as follows.

num_frame_in_RAU: the number of frames or field pairs constituting the RAU frame_flag: a flag for determining whether the frame or the field pair frame_type: frame type (I frame, P frame, B frame, BI frame, Skipped frame) Etc.) field_pair_type: field pair type (I / I picture, I / P picture, P / I picture, etc.)

  Here, in field_pair_type, it is possible to distinguish between the P / I picture for which the decoding operation is guaranteed to be reset and the P / I picture for which the decoding operation is not guaranteed to be reset by using different identifiers.

  FIG. 54B is a table showing a list of frame or field types constituting the RAU in decoding order. The definition of each parameter is as follows.

num_picture_in_RAU: the number of frames or fields constituting the RAU frame_flag: a flag for discriminating whether the frame or the field picture_type: the type of the frame or field

  Here, with respect to the P picture which is the first field of the P / I picture, the P picture of the P / I picture whose decoding operation is guaranteed to be reset, and the P / I picture whose decoding operation is not guaranteed to be reset A P picture is distinguished by using a different identifier in picture_type.

  The frame_flag may include not only the frame or the field but also information on 3: 2 pull-down (telecine conversion) in the frame.

  Providing a point for resetting the decoding operation in the RAU is particularly effective when the playback time length of the RAU is long. Here, the RAU time length depends on the I picture interval, and the I picture has a larger amount of code than the P picture and B picture, so the RAU time length is increased to increase the I picture interval. As a result, the bit rate can be reduced. Therefore, it is effective to increase the RAU time length at a low bit rate. For this reason, only when the playback time length of the RAU is equal to or greater than a predetermined value or the bit rate of the encoded stream is equal to or less than the predetermined value, the reference relationship restriction for the P / I picture is applied, or the RAU map May be added to indicate whether there is a restriction on the reference relationship for the P / I picture. Furthermore, the playback time length of the RAU may be set to a predetermined time or less in consideration of playback quality at the time of special playback such as high-speed playback that plays back only the first I picture of the RAU. Also, the difference value between the display times or the decoding times between the random access points pointed to by the time map may be set to a predetermined value or less. Here, it should be noted that in the open GOP type RAU, the display time of the B picture or the like displayed first in the RAU is earlier than the display time of the I picture pointed to by the time map.

  When there are a plurality of P / I pictures in the RAU, it is possible to determine whether or not to restrict the reference relationship for the P / I picture in consideration of the ease of special reproduction. For example, when providing a point at which the decoding operation can be reset during special playback in a predetermined unit such as one second, the P / I picture is set so that the difference in display time between P / I pictures is equal to or less than the predetermined unit. The reference relationship about can be constrained.

  A method for indicating whether or not there is a point that can reset the decoding operation at the time of special reproduction between two consecutive random access points indicated by the time map even in the case shown in FIG. FIG. 48 is an example in which an RAU map is placed before an RAU that is indicated as a random access point by a time map, and information about an RAU between the next random access point is shown. Here, two RAUs exist between the random access points, and each of the playback time lengths is 1 second. Since the RAU can be used as a point to reset the decoding operation, it can be determined from which RAU the decoding should be started based on the playback time length of each RAU. Further, in the RAU map, it may be indicated whether the head of each RAU map is a P / I picture. The RAU map in FIG. 48 and the map information for each RAU shown in FIG. 47 may be used together.

(Embodiment 6)
In the sixth embodiment, an image coding method and an image coding apparatus for generating data shown in the fifth embodiment will be described.

  FIG. 49 is a flowchart showing an operation when determining whether or not to restrict the reference relationship of pictures in the image coding method according to the present embodiment. First, in step S2001, it is determined whether to encode the current frame or field pair as a P / I picture, and the process proceeds to step S2002. In step S2002, it is determined whether or not the current frame or field pair is a picture constituting the first frame of the RAU. If it is a picture constituting the first frame, the process proceeds to step S2003. Otherwise, the process proceeds to step S2004. In step S2003, it is determined whether or not the current frame or field pair is a picture for which the decoding operation can be reset. If it is a picture to be reset, the process proceeds to step S2004, and if not, the process ends. In step S2004, it is determined that the reference relationship of subsequent pictures is restricted so that a picture whose display order is later than the current P / I picture in the RAU does not refer to the P picture in the current P / I picture. Note that all P / I pictures may be pictures for which the decoding operation can be reset.

  FIG. 50 is a flowchart showing an operation when a RAU map is added to the head of the RAU. In this flowchart, the RAU map generation operation is mainly described, and the details of the encoding operation of each picture are omitted. First, in step S2101, it is determined whether or not the reference relationship of the subsequent picture is restricted in relation to the P / I picture. In step S2102, the picture reference relationship is determined so as to satisfy the constraint determined in step S2101, and the process advances to step S2103. In step S2103, it is determined whether or not the current picture is the last picture of the RAU. If it is the last picture, the process proceeds to step S2104; otherwise, the process ends. In step S2013, it may be determined whether the current picture is the last P / I picture in the RAU. Finally, in step S2014, a RAU map storing information about the P / I picture is generated and added before the picture data constituting the RAU.

  FIG. 51 is a block diagram showing a configuration of an image encoding device 2000 that implements the image encoding method of the present embodiment. The image coding apparatus 2000 is different from the conventional image coding apparatus 1 in that a P / I constraint determination unit Plim and a map information creation unit MapInfo are newly provided and the operation of the prediction structure determination unit PTYPE is different. The P / I constraint determination unit Plim performs the processing from step S2001 to step S2004. When the picture to be encoded is a P / I picture, the subsequent picture in the RAU is the P picture of the P / I picture. Decide whether or not to reference. The prediction structure determination unit PTYPE determines a picture coding type, a reference relationship, and the like so as to satisfy the conditions determined by the P / I constraint determination unit Plim. On the other hand, the map information creation unit MapInfo generates the RAU map described in the fifth embodiment.

(Embodiment 7)
In the seventh embodiment, an image decoding method and an image decoding apparatus for decoding data shown in the fifth embodiment will be described.

FIG. 52 is a flowchart showing a decoding operation during special playback in the image decoding method according to the present embodiment. This method is particularly effective in determining a picture to start decoding when performing jump reproduction or reverse reproduction by a user operation or the like. First, in step S2201, it is determined whether or not to start playback from a picture (Pic_st) different from the picture pointed to by the time map. When playback starts from a picture different from Pic_st, the process proceeds to step S2202, otherwise The process proceeds to step S2204. In step S2202, it is determined whether there is a P / I picture (PI_st) whose decoding order is earlier than Pic_st and whose decoding operation can be reset. Here, at the time of determination, referring to the RAU map, the decoding order is
・ Before Pic_st,
After the first picture of the RAU pointed to by the time map,
Search for a P / I picture whose decoding operation can be reset. Note that PI_st is a picture whose decoding order is earlier than Pic_st and whose decoding order is closest to Pic_st.

  Next, in step S2203, it is determined to start decoding from the I picture in PI_st. In step S2204, it is determined to start decoding from the first picture of the RAU pointed to by the time map.

  FIG. 53 is a block diagram illustrating a configuration of an image decoding device 3000 that implements the image decoding method according to the present embodiment. The image decoding device 3000 is different from the conventional image decoding device 3 in that it includes a PI information acquisition unit PIsel.

  When a signal TrickMode instructing special reproduction is input to the PI information acquisition unit PIsel by a user operation or the like, the PI information acquisition unit PIsel acquires RAU map information MapInf from the variable length decoding unit VLD. Here, the variable length decoding unit VLD acquires the RAU map by analyzing the encoded stream and inputs it to the PI information acquisition unit PIsel. Further, the PI information acquisition unit PIsel analyzes the information MapInf of the RAU map, determines a picture to start decoding, and inputs information SelPic indicating the determined decoding start picture to the stream extraction unit EXT.

(Embodiment 8)
Furthermore, by recording the program for realizing the image encoding method and the image decoding method shown in each of the above embodiments on a recording medium such as a flexible disk, the processing shown in each of the above embodiments Can be easily implemented in an independent computer system.

  FIG. 42 is an explanatory diagram when the image encoding method and the image decoding method of each of the above embodiments are implemented by a computer system using a program recorded on a recording medium such as a flexible disk.

  FIG. 42B shows an appearance, a cross-sectional structure, and a flexible disk as viewed from the front of the flexible disk, and FIG. 42A shows an example of a physical format of the flexible disk that is a recording medium body. The flexible disk FD is built in the case F, and a plurality of tracks Tr are formed concentrically on the surface of the disk from the outer periphery toward the inner periphery, and each track is divided into 16 sectors Se in the angular direction. ing. Therefore, in the flexible disk storing the program, the program is recorded in an area allocated on the flexible disk FD.

  FIG. 42C shows a configuration for recording and reproducing the program on the flexible disk FD. When the program for realizing the image encoding method and the image decoding method is recorded on the flexible disk FD, the program is written from the computer system Cs via the flexible disk drive. When the image encoding method and the image decoding method for realizing the image encoding method and the image decoding method by a program in a flexible disk are constructed in a computer system, the program is read from the flexible disk by a flexible disk drive, and the computer Transfer to system.

  In the above description, a flexible disk is used as the recording medium, but the same can be done using an optical disk. Further, the recording medium is not limited to this, and any recording medium such as an IC card or a ROM cassette capable of recording a program can be similarly implemented.

  The image encoding method and the image decoding method according to the present invention can be applied to all devices having special reproduction functions such as high speed and reverse reproduction when reproducing a VC-1 stream, and special reproduction functions are important. This is particularly effective in the optical disc related equipment.

Data hierarchy diagram of HD-DVD Logical space configuration diagram on HD-DVD Outline block diagram of HD-DVD player Configuration block diagram of HD-DVD player Illustration of HD-DVD application space Configuration diagram of MPEG stream (VOB) Pack configuration diagram The figure explaining the relationship between AV stream and a player structure AV data continuous supply model diagram to track buffer VOB information file configuration diagram Illustration of time map Playlist file structure diagram Configuration diagram of program files corresponding to playlists BD disk overall management information file configuration diagram Diagram of the file that records global event handlers Diagram explaining examples of time events Diagram explaining examples of user events Diagram explaining an example of a global event handler Virtual machine configuration diagram Diagram of player variable table Figure showing an example of event handler (time event) Diagram showing an example of event handler (user event) Flow chart of basic processing of player Flow chart of playlist playback processing Event processing flowchart Subtitle processing flowchart The figure explaining the P / I picture of the RAU head The figure explaining the 1st special reproduction example in a P / I picture The figure explaining the subject at the time of using a P / I picture for special reproduction Relationship diagram between time map and P / I picture Relationship diagram between time map with picture type attribute and P / I picture Explanatory drawing of a P / I picture referring to an I picture in the second field The figure explaining the 2nd special reproduction example in a P / I picture The figure which shows the stream structure of Embodiment 1 of this invention The block diagram which shows the structure of the conventional image coding apparatus. The block diagram which shows the structure of the conventional image decoding apparatus Flow chart showing operation of conventional image decoding apparatus The flowchart which shows operation | movement of the image coding method of Embodiment 3 of this invention. FIG. 3 is a block diagram showing a configuration of an image coding apparatus according to Embodiment 3 of the present invention. The flowchart which shows operation | movement of the image decoding method of Embodiment 4 of this invention. Block diagram showing a configuration of an image decoding apparatus according to Embodiment 4 of the present invention. Recording medium on which program for realizing image encoding method and image decoding method of the present invention is recorded The figure which shows the subject in the case of starting reproduction from the middle of the random access unit in the conventional data structure The figure which shows the subject when the scene change occurs in the conventional data structure The figure which shows the 1st structural example of the random access unit of this Embodiment 5. The figure which shows the 2nd structural example of the random access unit of this Embodiment 5. The figure explaining the 1st auxiliary information added to the head of random access unit in this Embodiment 5. The figure explaining the 2nd auxiliary information added to the head of random access unit in this Embodiment 5. The flowchart which shows the operation | movement at the time of restrict | limiting the reference relationship of a picture in the image coding method of this Embodiment 6. The flowchart which shows operation | movement of the image coding method of this Embodiment 6. Block diagram showing the configuration of the image coding apparatus according to the sixth embodiment The flowchart which shows operation | movement of the image decoding method of this Embodiment 7. Block diagram showing the configuration of the image decoding apparatus of the seventh embodiment The figure which shows the syntax example of a RAU map

Explanation of symbols

LIMIT type limit unit PTYPE prediction structure determination unit VLC variable length coding unit PicMem picture memory

Claims (12)

An information recording medium that records at least a stream obtained by multiplexing encoded data of moving images and management information thereof, wherein the management information includes reproduction time information, size information, and information on the moving images in the stream. Record start address information,
The encoded data of the moving image is composed of one or more randomly accessible units,
In the moving picture coding method, when a frame image is coded in a field unit, a field pair coded with a first field as a forward prediction picture and a second field as an in-plane coded picture. When you can use
An information recording medium for storing identification information indicating whether or not the field pair exists in the encoded data. The random access unit includes
A closed random access unit that prohibits bi-predictive pictures in the random access unit from referring to pictures in the previous random access unit in decoding order; and
An open random access unit that allows bi-predictive pictures in a random access unit to refer to pictures in the previous random access unit in decoding order;
There are two types of
The identification information is information indicating whether the random access unit is a closed type,
The information recording medium according to claim 1, wherein when the random access unit is a closed type, the field pair does not exist at the head of the random access unit. The information recording medium according to claim 1, wherein the identification information is information indicating whether a bit rate of the encoded stream is equal to or less than a predetermined value. The moving image is divided into a plurality of playback sections according to playback time, and the management information stores information for continuously playing the one or more playback sections in the one or more moving images,
The identification information is stored in the management information and indicates whether the playback sections that are continuously played are seamlessly connected;
The information recording medium according to claim 1, wherein when the seamless connection is indicated, a head of the reproduction section to be a connection destination is not the field pair. The moving image is divided into a plurality of playback sections according to playback time, and the management information stores information for continuously playing the one or more playback sections in the one or more moving images,
The identification information is information that is stored in the management information and identifies whether or not the continuously reproduced sections belong to different moving image streams,
2. The information recording medium according to claim 1, wherein when it is indicated that the video data belongs to the different video stream, the head of the playback section to be connected is not the field pair. An image encoding method for encoding a moving image into one or more random access units,
In the moving picture coding method, when a frame image is coded in a field unit, a field pair coded with a first field as a forward prediction picture and a second field as an in-plane coded picture. When you can use
An auxiliary information creating step for creating information indicating whether the first picture of the random access unit is the field pair;
An image encoding method comprising: the generated auxiliary information; and an encoding step of encoding pixels to generate an encoded stream. An image encoding device that encodes a moving image into one or more random access units,
In the moving picture coding method, when a frame image is coded in a field unit, a field pair coded with a first field as a forward prediction picture and a second field as an in-plane coded picture. When you can use
Auxiliary information creating means for creating information indicating whether the first picture of the random access unit is the field pair;
Encoding means for encoding the created auxiliary information and pixels to create an encoded stream;
An image encoding apparatus comprising: An image decoding method for decoding and reproducing encoded data recorded on an information recording medium according to claim 1, comprising:
When the identification information indicates that the first picture of the random access unit is not the field pair, the display step of displaying the first field and the second field in the first picture as the first and second, respectively ,
An image decoding method comprising: An image decoding apparatus for decoding and reproducing encoded data recorded on an information recording medium according to claim 1,
When the identification information indicates that the first picture of the random access unit is not the field pair, display means for displaying the first field and the second field in the first picture first and second respectively, ,
An image decoding apparatus comprising: An information recording medium that records at least a stream obtained by multiplexing encoded data of moving images and management information thereof, wherein the management information includes reproduction time information, size information, and information on the moving images in the stream. Record start address information,
The encoded data of the moving image is composed of one or more randomly accessible units,
In the moving picture coding method, when a frame image is coded in a field unit, a field pair coded with a first field as a forward prediction picture and a second field as an in-plane coded picture. When you can use
When the picture different from the head of the random access unit is the field pair, the picture in the random access unit, which is later in display order than the field pair, is the field pair. Guaranteed not to reference the first field,
An information recording medium characterized in that information indicating the guarantee is stored in the stream. An information recording medium that records at least a stream obtained by multiplexing encoded data of moving images and management information thereof, wherein the management information includes reproduction time information, size information, and information on the moving images in the stream. Record start address information,
The encoded data of the moving image is composed of one or more randomly accessible units,
In the moving picture coding method, when a frame image is coded in a field unit, a field pair coded with a first field as a forward prediction picture and a second field as an in-plane coded picture. When you can use
When the picture different from the head of the random access unit is the field pair, the picture in the random access unit, which is later in display order than the field pair, is the field pair. With or without reference to the first field,
An information recording medium characterized in that information indicating whether a picture whose display order is later than the field pair refers to the first field of the field pair is stored in the stream. An information recording medium that records at least a stream obtained by multiplexing encoded data of moving images and management information thereof, wherein the management information includes reproduction time information, size information, and information on the moving images in the stream. Record start address information,
The encoded data of the moving image is data in which a plurality of grouping units each grouping one or more pictures are concatenated,
The management information stores list information of the grouping units that can be randomly accessed,
In the moving picture coding method, when a frame image is coded in a field unit, a field pair coded with a first field as a forward prediction picture and a second field as an in-plane coded picture. When you can use
The information recording medium characterized in that the stream stores information indicating whether or not a head picture of the grouping unit not pointed out from the list information is the field pair.

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