JP4036363B2 - Image processing apparatus and image processing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an image processing apparatus that processes encoded data of an image, and more particularly to a technique for restricting image browsing in this type of image processing apparatus.
[0002]
[Prior art]
  For example, in a digital camera or digital video camera, a photographed image is compressed and encoded and recorded on a storage medium. The recorded image can be basically reproduced and viewed by anyone, but there are cases where it is desirable to restrict viewing of the image to persons other than the photographer. This viewing restriction is, for example, that an original high-quality image cannot be reproduced, although an outline of the image can be confirmed.
[0003]
  In addition, for example, in a system in which a large number of images are accumulated and the images are browsed via a network such as the Internet, a user who wants to restrict browsing of specific images or all images in the same manner, except for those who have registered in advance. There is.
[0004]
  Regarding such image browsing restrictions, there are known image coding apparatuses and methods that divide image data into frequency bands and scramble each frequency band data, for example, in units of bit planes before encoding. (For example, refer to Patent Document 1).
[0005]
  Further, as image encoding methods related to the present invention, there are JPEG2000 (ISO / IEC FCD 15444-1) and Motion-JPEG2000 (ISO / IEC FCD 15444-3) (for example, see Non-Patent Document 1). Motion-JPEG2000 handles a moving image with each of a plurality of continuous still images as a frame, but each frame conforms to JPEG2000.
[0006]
[Patent Document 1]
      JP 2001-218184 A
[Non-Patent Document 1]
      Yasuyuki Nomizu, “Next Generation Image Coding JPEG2000”, Trikes, Inc., February 13, 2001
[0007]
[Problems to be solved by the invention]
  It is desirable to use a standardized method for image compression / decompression. However, in the method of performing scrambling processing of each frequency band data in the encoding process as described above, the encoding device has a non-standard configuration. The decryption process also requires descrambling, and the decryption device still has a non-standard configuration.TheEnd up. In addition to such problems, there is also a problem that scrambling processing and descrambling processing of each frequency band data in units of bit planes are relatively time-consuming processing. This is extremely disadvantageous when all or part of the compression / decompression processing is realized by software. In addition, in order to restrict viewing of encoded data later, it is necessary to decode and decompress the encoded data once. Also, even if you restrict viewing of images, it is not only for the purpose of preventing viewing itself, but it is also impossible to viewsoThere are various cases, such as when you want to make it difficult to view, but when you want to understand the contents of the image to some extent and encourage the acquisition of the right to view normally. However, it is difficult to apply such various types of browsing restrictions by the method using the scramble process described above.
[0008]
  Therefore, the object of the present invention can be summarized as follows: (1) Image browsing restrictions without changing the image compression encoding process or decoding expansion process in various image processing apparatuses that process encoded image data. Or make it possible to release it. (2) To be able to carry out restriction and cancellation of browsing with simple and time-saving processing. (3) To enable various viewing restrictions. (4) By making it possible to restrict viewing, release, or change the method of viewing restriction at any time after compression encoding of an image and without decoding and decompressing the encoded data is there.
[0009]
[Means for Solving the Problems]
  The image processing apparatus according to any one of claims 1 to 9 is an image processing apparatus that processes encoded data of an image compliant with JPEG2000, and rewrites tag information of the encoded data of the image to restrict image browsing. It has tag information rewriting means.
[0010]
  In the image processing apparatus according to the first aspect, the tag information rewriting means rewrites the Isot value of the SOT marker segment included in the tile header of the encoded data.
[0011]
In the image processing apparatus of the second aspect, the tag information rewriting means rewrites the values of Xsiz and Ysiz of the SIZ marker segment included in the main header of the encoded data.
[0012]
  In the image processing apparatus according to claim 3, the tag information rewriting means rewrites the value of XOsiz or YOsiz of the SIZ marker segment included in the main header of the encoded data.
[0013]
  In the image processing apparatus according to a fourth aspect of the present invention, the tag information rewriting means rewrites the SPrgn value of the RGN marker segment included in the main header or tile header of the encoded data.
[0014]
  In the image processing apparatus of the fifth aspect, the tag information rewriting means rewrites a value relating to color conversion in SGcod of the COD marker segment included in the main header or tile header of the encoded data.
[0015]
  In the image processing apparatus according to the sixth aspect, the tag information rewriting means rewrites the value of Csiz of the SIZ marker segment included in the main header of the encoded data.
[0016]
  In the image processing apparatus according to the seventh aspect, the tag information rewriting means rewrites the value of Xcrg (i) or Ycrg (i) of the CRG marker segment included in the main header of the encoded data.
[0017]
  In the image processing apparatus according to an eighth aspect of the present invention, the tag information rewriting means rewrites the number of decomposition levels in the SPcod of the COD marker segment included in the main header or tile header of the encoded data.
[0018]
  In the image processing apparatus according to the ninth aspect, the tag information rewriting unit includes the XRsiz (i) or Y of the SIZ marker segment included in the main header of the encoded data. Rewrite the value of Rsiz (i).
[0019]
  The image processing method according to any one of claims 10 to 18, wherein the encoded data of the image conforming to JPEG2000 is processed, and tag information for rewriting the tag information of the encoded data for restricting image browsing. A rewriting process is included.
[0020]
  In the image processing method according to claim 10, the tag information rewriting step rewrites the Isot value of the SOT marker segment included in the tile header of the encoded data.
[0021]
  In the image processing method according to an eleventh aspect, the tag information rewriting step rewrites the values of Xsiz and Ysiz of the SIZ marker segment included in the main header of the encoded data.
[0022]
  In the image processing method of the present invention, the tag information rewriting step rewrites the value of XOsiz or YOsiz of the SIZ marker segment included in the main header of the encoded data.
[0023]
  In the image processing method of the present invention, the tag information rewriting step rewrites the SPrgn value of the RGN marker segment included in the main header or tile header of the encoded data.
[0024]
  In the image processing method according to the fourteenth aspect of the present invention, the tag information rewriting step rewrites a value relating to color conversion in SGcod of a COD marker segment included in a main header or tile header of the encoded data.
[0025]
  In the image processing method according to the fifteenth aspect, the tag information rewriting step rewrites the value of Csiz of the SIZ marker segment included in the main header of the encoded data.
[0026]
  In the image processing method of the sixteenth aspect of the invention, the tag information rewriting step rewrites the value of Xcrg (i) or Ycrg (i) of the CRG marker segment included in the main header of the encoded data.
[0027]
  In the image processing method of the seventeenth aspect, the tag information rewriting step rewrites the number of decomposition levels in the SPcod of the COD marker segment included in the main header or tile header of the encoded data.
[0028]
  In the image processing method of the present invention, the tag information rewriting step rewrites the value of XRsiz (i) or YRsiz (i) of the SIZ marker segment included in the main header of the encoded data.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
  In the embodiment described below, encoded data of JPEG2000 (ISO / IEC FCD 15444-1) or encoded data of Motion-JPEG2000 (ISO / IEC FCD 15444-3) is a processing target. JPEG2000 is detailed in, for example, Non-Patent Document 1 described above, but JPEG2000 will be described in a range related to the following embodiments.
[0030]
  FIG. 1 is a simplified block diagram for explaining the algorithm of JPEG2000. Image data to be compression-encoded (image data of each frame in the case of handling moving images) is divided into non-overlapping rectangular areas called tiles for each component, and processed for each component in units of tiles. However, it is possible to make the tile size the same as the image size, that is, not to perform tile division.
[0031]
  The tile image is subjected to color space conversion from RGB data or CMY data to YCrCb data for the purpose of improving the compression rate (step S1). This color space conversion may be omitted.
[0032]
  A two-dimensional wavelet transform (discrete wavelet transform: DWT) is performed on each tile image of each component after color space conversion (step S2).
[0033]
  FIG. 2 is an explanatory diagram of wavelet transformation when the number of decomposition levels is 3. FIG. The tile image (decomposition level 0) shown in FIG. 2A is divided into 1LL, 1HL, 1LH, and 1HH subbands as shown in FIG. 2B by two-dimensional wavelet transform. By applying the two-dimensional wavelet transform to the coefficients of the 1LL subband, the subbands are divided into 2LL, 2HL, 2LH, and 2HH as shown in FIG. By applying the two-dimensional wavelet transform to the coefficients of the 2LL subband, the subbands are divided into 3LL, 3HL, 3LH, and 3HH as shown in FIG. Regarding the relationship between the decomposition level and the resolution level, each subband in FIG. 2D enclosed in parentheses indicates the resolution level of the subband.
[0034]
  The wavelet coefficients obtained by recursive division (octave division) of such low frequency components (LL subband coefficients) are quantized for each subband (step S3). In JPEG2000, both lossless (lossless) compression and lossy (lossy) compression are possible. In the case of lossless compression, the quantization step width is always 1, and quantization is not performed at this stage.
[0035]
  Each subband coefficient after quantization is entropy-coded (step S4). For this entropy coding, an encoding method called EBCOT (Embedded Block Coding with Optimized Truncation) consisting of block division, coefficient modeling and binary arithmetic coding is used, and a bit plane of each subband coefficient after quantization is used. Coding is performed for each block called a code block from the upper plane to the lower plane.
[0036]
  The last two steps S5 and S6 are a code forming process. First, in step S5, a packet is created by combining the codes of the code blocks generated in step S4. In the next step S6, the packets generated in step S5 are arranged according to the progression order, and necessary tag information is added to create encoded data of a predetermined format. In JPEG 2000, five types of progression orders are defined for the code order control by combinations of resolution level, precinct (position), layer, and component (color component).
[0037]
  The format of JPEG2000 encoded data generated in this way is shown in FIG. As shown in FIG. 3, the encoded data starts with a tag called an SOC marker indicating the beginning thereof, followed by tag information called a main header (Main Header) describing an encoding parameter, a quantization parameter, and the like, After that, the code data for each tile follows. The code data for each tile starts with a tag called an SOT marker, and consists of tag information called a tile header (Tile Header), a tag called an SOD marker, and tile data (Tile Data) containing the code string of each tile. Is done. A tag called an EOC marker indicating the end is placed after the last tile data.
[0038]
  Here, the precinct, the code block, the packet, and the layer will be briefly described. There is a size relationship of image ≧ tile ≧ subband ≧ precinct ≧ code block.
[0039]
  A precinct is a rectangular region of subbands, and a set of three regions at the same spatial position of HL, LH, and HH subbands having the same decomposition level is treated as one precinct. However, in the LL subband, one area is treated as one precinct. It is also possible to make the precinct size the same as the subband. A rectangular area obtained by dividing the precinct is a code block. FIG. 4 illustrates one precinct and code block at the decomposition level 1. A set of three regions at the same spatial position, denoted as precinct in the figure, is treated as one precinct.
[0040]
  A packet is a collection of a part of the codes of all code blocks included in the precinct (for example, codes of three bit planes from the most significant bit to the third bit). Packets with an empty code are allowed. The code of the code block is collected to generate a packet, and the encoded data is formed by arranging the packet according to a desired progression order. The portion below SOD for each tile in FIG. 3 is a set of packets.
[0041]
  When packets of all precincts (that is, all code blocks and all subbands) are collected, a part of the code for the entire image area (for example, the bits from the most significant bit plane to the third frame of the wavelet coefficients for the entire image area) This is a layer (however, as in the following example, not all precinct packets need to be included in the layer). Therefore, as the number of layers decoded at the time of expansion increases, the quality of the reproduced image improves. That is, the layer can be said to be a unit of image quality. When all layers are collected, it becomes the code of all bit planes of the entire image.
[0042]
  FIG. 5 shows an example of packets and layers when the number of decomposition levels = 2 (the number of resolution levels = 3). In the figure, a vertically small rectangle is a packet, and the number shown inside is a packet number. The layer is illustrated as a horizontally long rectangular region with shading. That is, in this example, layer 0 consisting of the code of the packet number 0-16, layer 1 consisting of the code of the packet number 17-33, layer 2, consisting of the code of the packet number 34-50, packet number From layer 3 consisting of codes of packets 51 to 67, layer 4 consisting of codes of packets of packet numbers 68 to 84, layer 5 consisting of codes of packets of packet numbers 85 to 101, and codes of packets of packet numbers 102 to 118 Layer 6 consisting of codes of packets with packet numbers 119 to 135, layer 8 consisting of codes of packets with packet numbers 136 to 148, and layer 9 consisting of codes of packets with the remaining packet numbers 149 to 161 It is divided into 9 layers. Note that the correspondence between packets and precincts changes variously depending on the difference in progression order, the number of layer divisions, and the like, and the layer configuration shown above is merely an example.
[0043]
  In JPEG2000, five progression orders of LRCP, RLCP, RPCL, PCRL, and CPRL are defined. Here, L is a layer, R is a resolution level, C is a component, and P is a precinct (Position).
[0044]
  In the case of LRCP progression, the order of packet arrangement (when encoding) or packet interpretation (when decoding) can be expressed by the following for loop nested in the order of L, R, C, and P.
        for (layer) {
          for (resolution level) {
            for (component) {
              for (Precinct) {
                  Place packet: When encoding
                  Interpret packets: when decrypting
          }
        }
      }
    }
[0045]
  Specifically, the image size = 100 × 100 pixels (no tile division), the number of layers = 2, the number of resolution levels = 3 (level 0 to 2), the number of components = 3, and the precinct size = 32 × 32 The 36 packets in the case are arranged and interpreted in the order as shown in FIG.
[0046]
  In the case of RLCP progression,
        for (resolution level) {
          for (layer) {
            for (component) {
              for (Precinct) {
                  Place packet: When encoding
                  Interpret packets: when decrypting
          }
        }
      }
    }
In this order, packet arrangement (when encoding) or packet interpretation (when decoding) is performed. In the case of other progression orders, a similar nested for loop determines the arrangement order or interpretation order of packets.
[0047]
  In addition to the for loops in the progression order described above, there are also loops related to tiles. Although not specified in the JPEG2000 standard, on the decoder side,
      while (as long as there are tiles) {
        for (resolution level) {
          for (layer) {
            for (component) {
              for (Precinct) {
                  Interpret packets: when decrypting
            }
          }
        }
      }
    }
The configuration is as follows. As will be described later, a tile number is described in the SOT marker segment of the tile header, and a tile size and an image size are described in the SIZ marker segment of the main header. Thus, for example, when the size of the image is rewritten to ½, the decoder determines that there is a number that falls within the size range, depending on the implementation, and the tile having the tile number within that number. It is usual to try to decode the code.
[0048]
  The JPEG 2000 encoded code outlined above can be partially decoded and expanded on the decoder side by rewriting the tag information, or can be decoded and expanded differently from the original decoding expansion. In the present invention, since browsing of images is performed using such a property, an outline of tag information added to JPEG 2000 encoded data is shown to the extent necessary for the following description.
  FIG. 7 shows the configuration of the main header. Each marker segment of SIZ, COD, and QCD is essential, but the other marker segments are optional.
  FIG. 8 shows the configuration of the tile header. (A) is a header added to the head of tile data, and (b) is a header added to the head of the divided tile subsequence when the inside of the tile is divided into a plurality. There is no mandatory marker segment in the tile header, all are optional.
  FIG. 9 shows a list of markers and marker segments.
  The SOT marker segment configuration is shown in FIG. 10, the SIZ marker segment configuration is shown in FIG. 11, the COD marker segment configuration is shown in FIG. 12, the CRG marker segment configuration is shown in FIG. 13, and the RGN marker segment configuration is shown in FIG. Show.
[0049]
  Embodiment 1 FIG. 15 is a block diagram for explaining Embodiment 1 of the present invention.
[0050]
  The image processing apparatus shown here is an input interface unit 1000 that directly captures encoded data from a device such as an external personal computer through a wired or wireless transmission path or network as means for capturing encoded data of a still image or a moving image. An image capturing unit 1001 that captures a subject and inputs image data of a still image or a moving image, and a JPEG 2000-compliant image compressing unit 1002 that compresses and encodes the image data to generate encoded data. Note that an aspect including only the input interface unit 1000 as means for capturing encoded data is also included in the present invention. Further, the input interface unit 1000 can be replaced with a means for reading encoded data from a storage medium such as a memory card, and such an aspect is also included in the present invention.
[0051]
  The image processing apparatus includes one or more storage units 1006 as means for recording encoded data of an image. The storage unit 1006 records data on a replaceable medium such as various memory cards widely used in digital cameras or the like, or a fixed medium such as a hard disk.
[0052]
  Reference numeral 1003 denotes an output interface unit for outputting encoded data to a device such as an external personal computer through a wired or wireless transmission path or network. The encoded data recorded in the storage unit 1006 is output to the outside via the output interface unit 1003, or the encoded data obtained by compressing and encoding the image data captured by the image capturing unit 1001 by the image compressing unit 1002. Can be output to the outside via the output interface unit 1003 as it is.
[0053]
  This image processing apparatus includes a JPEG2000-compliant image decompression unit 1007 for decoding and decompressing encoded data, a display unit 1008 for displaying images, a control unit 1009 for controlling the entire device, and a control unit 1009. An operation unit 1010 is provided for a user to input various instructions.
[0054]
  The biggest feature of this image processing apparatus is that it includes a tag information rewrite processing unit 1004 and a tag information restoration processing unit 1005 related to the browsing restriction of encoded data. The tag information rewrite processing unit 1004 is a means for performing processing to rewrite tag information of encoded data of an image in order to restrict image browsing. On the other hand, the tag information restoration processing unit 1005 restores the tag information of the encoded data of the image to the content before being rewritten in order to release the viewing restriction applied to the image by rewriting the tag information by the tag information rewriting processing unit 1004. It is a means for performing processing for recovery. As will be apparent from the following description, it is not necessary to use the tag information recovery processing unit 1005 depending on how the browsing restriction is applied, so the tag information recovery processing unit 1005 can be omitted, and such an aspect is also possible. Included in the present invention.
[0055]
  This image processing apparatus has a plurality of operation modes related to image browsing restriction or cancellation thereof, and the user can designate any operation mode to the control unit 1009 from the operation unit 1010. The operation in each operation mode will be described below.
[0056]
  First, operation modes 1 to 5 for restricting browsing on images will be described. When instructing these operation modes, the user can specify a tag information rewriting method for restricting browsing. If not specified by the user, the default tag information rewriting method is selected by the control unit 1009. A tag information rewriting method for restricting browsing will be described later.
[0057]
  Operation Mode 1: As schematically shown in FIG. 16, encoded data of an image taken in via the input interface unit 1000 under the control of the control unit 1009 or an image generated by the image compression unit 1002 The encoded data is recorded in the storage unit 1006 after the tag information is rewritten by the tag information rewrite processing unit 1004. Since the encoded data of the image in the storage unit 1006 is subject to viewing restrictions, for example, even if the encoded data is decoded and decompressed by the image decompressing unit 1007 and displayed on the display unit 1008, the viewing is restricted. . In addition, when the storage unit 1006 uses a replaceable medium such as a memory card, browsing is restricted even if the medium is taken out and the encoded data is reproduced by a personal computer or the like.
[0058]
  Operation mode 2: As schematically shown in FIG. 17, encoded data of an image is read from the storage unit 1006 under the control of the control unit 1009. The encoded data that is read is encoded data that is not subject to viewing restrictions. The encoded data is overwritten on the original encoded data in the storage unit 1006 after the tag information is rewritten by the tag information rewrite processing unit 1004. This operation mode is used when it is desired to restrict viewing later on the recorded image.
[0059]
  Operation mode 3: As schematically shown in FIG. 18, under the control of the control unit 1009, encoded data of an image that is not subjected to browsing restriction is read from the storage unit 1006. This encoded data is output to another personal computer or the like via the output interface unit 1003 after being restricted by the tag information rewriting processing unit 1004 to rewrite the tag information. Therefore, browsing is restricted even if another personal computer or the like tries to reproduce the encoded data of the image. This operation mode is used when it is desired to restrict viewing when externally outputting a recorded image.
[0060]
  Operation mode 4: As schematically shown in FIG. 19, under the control of the control unit 1009, for example, moving image data shot by the imaging unit 1001 is compression-encoded by the image compression unit 1002, and the encoded data The tag information is rewritten by the tag information rewrite processing unit 1004 and then output to another personal computer or the like via the output interface unit 1003. Therefore, browsing is restricted even if another personal computer or the like tries to reproduce the image. This operation mode is used when the encoded data of the image captured by the image capturing unit 1001 is stored in an external personal computer or the like, and when viewing of the image by an outsider is desired to be restricted.
[0061]
  Operation mode 5: As schematically shown in FIG. 20, encoded data of an image recorded in the storage unit 1006 that is not subject to viewing restrictions is read out, and tag information rewrite processing unit 1004 can rewrite the tag information. After that, the image decompression unit 1007 decodes and decompresses and the reproduced image data is displayed on the display unit 1008. However, since the tag information of the encoded data is rewritten, the original image data is not reproduced by the image decompression unit 1007, and thus browsing of the image can be restricted. By setting this operation mode to be selected in a normal image reproduction operation, it is possible to limit browsing by a person who does not have browsing authority even for an image recorded without limiting browsing.
[0062]
  The following operation modes 6 to 9 are modes for releasing the browsing restriction. When specifying this operation mode, it is necessary to input specific information for canceling the browsing restriction from the operation unit 1010. The tag information recovery processing unit 1005 is controlled by the control unit 1009 so as to operate on condition that this specific information is input. Therefore, those who cannot input such specific information cannot use the following operation modes.
[0063]
  The specific information for canceling the browsing restriction is a password set in the control unit 1009 in advance by the user who has applied the browsing restriction. This password does not necessarily consist of a combination of numbers and alphabets. In the first embodiment, the user can set in advance in the control unit 1009 an operation procedure for releasing the browsing restriction of various operation switches (operation buttons) provided in the operation unit 1010. When the operation switch is operated according to the preset operation procedure, the control unit 1009 determines that a password for canceling the browsing restriction has been input. Such a password setting and input method is convenient when applied to an image processing apparatus, such as a digital camera, for which it is not easy to directly input a password composed of alphabets and numbers from the operation unit 1010. As a specific example, the user selects arbitrary operation switches A, B, and C in the operation unit 1010, presses the operation switch B while pressing the operation switch A, and presses the operation switch C as it is. If you want to remove the browsing restriction by setting a simple operation procedure, perform the same operation.
[0064]
  Operation mode 6: As schematically shown in FIG. 21, under the control of the control unit 1009, encoded data of an image subjected to viewing restriction is read from the storage unit 1006. The encoded data is restored to the content before the tag information is rewritten by the tag information restoration processing unit 1004, and then decoded and decompressed by the image decompressing unit 1007. The reproduced image data is displayed on the display unit 1008. Since the tag information has been rewritten to the original content, normal image data is reproduced by the image decompression unit 1007, and thus the image can be viewed normally. This operation mode is used when the viewing restriction applied to the recorded image is canceled and normal viewing is desired.
[0065]
  Operation mode 7: As schematically shown in FIG. 22, under the control of the control unit 1009, encoded data of an image subjected to viewing restriction is read from the storage unit 1006. The read encoded data is overwritten with the original encoded data in the storage unit 1006 after the tag information is restored to the original content by the tag information recovery processing unit 1005. This mode of operation is for recorded imagesInThis is used when you want to remove the restricted viewing restrictions later. It is a matter of course that the same or different viewing restrictions can be applied by rewriting the tag information in the operation mode 2 after the viewing restrictions are released in this mode.
[0066]
  Operation mode 8: As schematically shown in FIG. 23, under the control of the control unit 1009, the encoded data of the image subjected to viewing restriction is read from the storage unit 1006, and the tag information restoration processing unit 1005 After the tag information is restored to the original content and the browsing restriction is released, the tag information is output to an external personal computer or the like via the output interface unit 1003. Therefore, the image can be browsed without restriction on an external personal computer or the like. This operation mode is used when the encoded data of an image subjected to viewing restriction is output to the outside after the viewing restriction is released.
[0067]
  Operation mode 9: As schematically shown in FIG. 24, encoded data of an image subjected to viewing restriction is input from an external personal computer or the like via the input interface unit 1000 under the control of the control unit 1009. . The encoded data is recorded in the storage unit 1006 after the tag information is restored to the original content by the tag information restoration unit 1005. Therefore, by decoding and decompressing the encoded data of the image recorded in the storage unit 1006 by the image decompression unit 1007, the image can be viewed without limitation.
[0068]
  Although not mentioned so far, for example, when it is desired to restrict the viewing of a recorded still image or moving image, or to cancel the viewing restriction, for example, a thumbnail of the recorded image Can be displayed on the display unit 1008 and an image can be designated on the screen. The JPEG 2000 encoded code can easily display a thumbnail image by decoding and decompressing only the code string of the lowest resolution, for example.
[0069]
  Hereinafter, rewriting of tag information for viewing restriction by the tag information rewriting processing unit 1004 will be described. In this embodiment, the user (A) a method of rewriting tag information so that the reproduction position of the region in the image becomes abnormal, and (B) a method of rewriting tag information so that a part of the image is not reproduced. (C) a method of rewriting tag information so that the reproduction color of the image becomes abnormal, (D) a method of rewriting tag information so that the reproduction resolution of the image becomes abnormal, and (E) the image is deformed. It is possible to select one of the methods for rewriting the tag information so that it is reproduced. Furthermore, for moving images, (F) a method of rewriting tag information for all frames, (G) a method of rewriting tag information for skipped frames, and (H) rewriting tag information with frames. One of the methods for switching the contents can be selected. The specific example is demonstrated about the rewriting method of the tag information for the above browsing restrictions.
[0070]
  (A) A method of rewriting tag information so that the reproduction position of an area in an image is always illegal:
  In the encoded data subjected to the tile division, the tile arrangement on the reproduced image can be made irregular by rewriting the tag information. Specifically, the tile numbers assigned to the tiles in the raster order are described in the Isot of the SOT marker segment (FIG. 10) in the tile header, but the value is rewritten. For example, in the case of an image that is divided into tiles and compressed and encoded as shown in FIG. 25A, the tile arrangement on the reproduced image is irregular as shown in FIG. Can be.
[0071]
  (B) Method of rewriting tag information so that part of an image is not reproduced: There are the following three methods, which can be selected by the user.
[0072]
  (B-1) In JPEG2000, the position of an image is expressed using coordinate axes called a reference grid. The SIZ marker segment (FIG. 11) in the main header includes parameters Xsiz and Ysiz that describe the horizontal and vertical sizes of the reference grid. The values of Xsiz and Ysiz are rewritten. This rewriting can prevent part of the image from being reproduced. FIG. 26 schematically shows such an example. In the original tag information, when Xsiz = Ysiz = 5 is rewritten to Xsiz = 3 and Ysiz = 3, the image to be reproduced is hatched as shown in FIG. 26 (a). It is played back with the part cut.
[0073]
  (B-2) In JPEG2000, it is possible to specify a positional deviation (offset) between the origin of the reference grid and the origin of the image. The SIZ marker segment XOsiz and YOsiz are parameters describing horizontal and vertical offsets. The values of XOsiz and YOsiz are rewritten. Even by such rewriting, part of the image can be prevented from being reproduced. FIG. 27 schematically shows such an example. By rewriting XOsiz = YOsiz = 0 to XOsiz = 3 and YOsiz = 0, the image to be reproduced as shown in FIG. 27A is shifted to the right as shown in FIG. Played with the side missing. It is also possible to use Xsiz and Ysiz together.
[0074]
  (B-3) JPEG2000 has a function to improve the image quality of a selected region (ROI region) over other regions, and the basic specification defines a MaxShift method by bit shift of wavelet coefficients in the ROI region. The RGN marker segment (FIG. 14) has a parameter called SPrgn in which the bit shift amount is described. This SPrgn is rewritten to a large value. By this rewriting, an area other than the ROI area can not be reproduced. FIG. 28 schematically shows such an example. In the case of an image in which the ROI area is shifted by 2 bits as shown in (a) (that is, SPrgn = 2), SPrgn = 10 (= 2 bits for ROI shift + normal display bits 0 to 7) 8 bits), the 8 bits from 0 to 7 are not reproduced. Therefore, on the reproduced image, for example, as shown in FIG. 5B, the ROI area is displayed, but the other areas are not displayed. When the tile header includes an RGN marker segment, the content has priority over the content of the RGN marker segment in the main header. Therefore, in the encoded data in which the RGN marker segment is included in the tile header, it is necessary to rewrite at least the SPrgn of the RGN marker segment.
[0075]
  (C) Method of rewriting tag information so that the reproduction color of the image becomes abnormal: There are the following three methods, which can be selected by the user.
[0076]
  (C-1) The COD marker segment (FIG. 12) has a code style parameter SGcod related to the component. This SGcod also describes a value indicating the presence / absence of component color conversion. If this value is 0, there is no color conversion, and if this value is 1, there is color conversion. Rewrite this value. By this rewriting, the image is reproduced with an abnormal color. For example, in encoded data that has undergone color conversion from RGB to YCbCr, the value is set to 1, but when this is rewritten to 0, color conversion is performed to return from YCbCr to RGB during decoding expansion. Therefore, the color of the reproduced image becomes unnatural. Similarly, when 0 is rewritten to 1, the reproduction color becomes unnatural.
[0077]
  (C-2) The SIZ marker segment (FIG. 11) has a parameter Csiz representing the number of components. An RGB color image or the like is set to Csiz = 3, but this is rewritten to 1. Thereby, a color image is reproduced as a monochrome image. Also, Csiz is rewritten to 2. By this rewriting, the image is reproduced as an unnatural color.
[0078]
  (C-3) The CRG marker segment (FIG. 13) includes parameters Xcrg (i) and Ycrg (i) representing the horizontal and vertical offset positions for each component. The values of Xcrg (i) and Ycrg (i) are rewritten. By this rewriting, the spatial positional relationship between the components is disturbed, resulting in a reproduction image of an unnatural color in which a so-called color shift occurs.
[0079]
(D) A method of rewriting tag information so that the reproduction resolution of an image becomes abnormal:
  The number of decomposition levels is described in SPcod of the COD marker segment (FIG. 12). Rewrite the number of decomposition levels to a smaller value. By this rewriting, decoding and decompression is performed only up to the number of decomposition levels after rewriting, so that the reproduced image is a low-resolution image having a smaller size than the original image.
[0080]
  (E) A method of rewriting tag information so that an image is deformed and reproduced:
  The SIZ marker segment (FIG. 11) includes parameters XRsiz (i) and YRsiz (i) that describe the number of samples in the horizontal and vertical directions for each component, which are rewritten. By this rewriting, the image can be deformed and reproduced.FIG.Schematically shows an example thereof. XRsiz (i) = YRsiz (i) = 2TheIf XRsiz (i) = 1 and YRsiz (i) = 2, the image to be reproduced as shown in FIG. 29 (a) is reproduced as an image as shown in FIG. 29 (b) expanded in the horizontal direction. When rewritten as XRsiz (i) = 4 and YRsiz (i) = 2, the image is reproduced as shown in (c) in the horizontal direction.
[0081]
  (F) Method of rewriting tag information for all frames:
  The tag information is rewritten by the method (A) to (E) selected by the user or the default method for the encoded data of all frames of the moving image.
[0082]
  (G) Method of rewriting tag information for a skipped frame:
  The tag information is rewritten by the method (A) to (E) selected by the user or the default method with respect to the encoded data of the frame specified by the user or by the default number of frames. For example, in the case where the method (C-2) for monochrome conversion is specified every other frame, as shown schematically in FIG. 30, color frames and monochrome frames are alternately arranged. It is played back as an unnatural and difficult-to-view moving image.
[0083]
  (H) Method of switching the contents of tag information rewriting by frame:
  The tag information having different contents is rewritten in the encoded data of each frame in the N consecutive frame periods designated by the user or default. The rewriting of tag information is performed by a user-selected or default method. FIG. 31 schematically shows an example thereof. This example is an example in which the number of decomposition levels of the encoded data of each frame is gradually rewritten to a small value every three frames (by the method (D)), and the image is extremely difficult to see. If N = infinity is specified, the number of decomposition levels gradually decreases from the first frame, and an image is not reproduced from a certain frame.
[0084]
  It is not always necessary to prepare all of the various tag information rewriting methods as described above. However, if various methods can be selected, for example, the user can restrict the viewing purpose or the shape suitable for the purpose. There is an advantage that it is possible to limit viewing. Here, the purpose or intention of the browsing restriction includes (a) preventing browsing, (b) making it difficult to browse, (c) conversely making it a psychological state that the user wants to browse normally, and so on.
[0085]
  Note that the procedure of each operation mode described above and the functions of the tag information rewrite processing unit 1004 and the tag information restoration processing unit 1005 may be realized using a general-purpose computer such as a personal computer or a dedicated computer such as a microcomputer. . A program therefor and various storage (recording) media readable by a computer in which the program is recorded are also included in the present invention.
[0086]
  << Embodiment 2 >> FIG. 32 is a block diagram for explaining Embodiment 2 of the present invention. An image processing apparatus 2000 shown here transmits encoded data of an image to an external apparatus 2200 via a network 2100 such as the Internet.
[0087]
  The image processing apparatus 2000 includes a storage unit A2011 in which encoded data of an image (still image or moving image) that is not subjected to browsing restriction is recorded, and encoding of an image that is subjected to browsing restriction by rewriting tag information. A storage unit B2002 in which data is recorded is provided. In addition, in order to restrict viewing of images that are not subject to viewing restrictions, a tag information rewriting processing unit 2003 for rewriting tag information of the encoded data, cancels viewing restrictions on images that are subject to viewing restrictions. Therefore, the tag information recovery processing unit 2004 for recovering the tag information of the encoded data to the original content, the communication control unit 2005 for communicating with the external device 2200 via the network 2100, the storage unit A2001 or the storage A determination unit 2006 that determines whether or not the external device 2200 that has requested browsing of the image recorded in the part B 2002 has the viewing authority, and a control unit 2007 that controls the entire device. Note that the tag information rewriting method for restricting browsing may be the same as that in the first embodiment, and thus description thereof will not be repeated.
[0088]
  Next, an operation when an image browsing request is received from an external device 2200 will be described. FIG. 33 is a flowchart for the explanation.
[0089]
  In the image processing apparatus 2000, the determination unit 2006 determines whether or not the external apparatus 2200 that is an image browsing request source (hereinafter abbreviated as a browsing request source apparatus) has the browsing authority (step S101). The determination unit 2006 has, for example, a table of user IDs of external devices having image browsing authority, and compares the user ID of the browsing request source apparatus with the table. It is determined that there is no viewing authority. Alternatively, it is determined that specific information indicating that the user has the browsing authority is transmitted from the browsing request source apparatus, and the determination unit 2006 determines that the user has the browsing authority when the specific information is received, and receives the information. If not, it is determined that there is no viewing authority.
[0090]
  When it is determined by the determination unit 2006 that the browsing request source device has the browsing authority (step S101, Yes), the control unit 2007 is an image recorded in the storage unit A2001 (step S102, Yes). Then, the encoded data of the image is directly transferred to the communication control unit 2005 and transmitted to the viewing request source apparatus (step S106). If the browsing target is an image recorded in the storage unit B2002 (No in step S102), the control unit 2007 uses the tag information restoration processing unit 2004 to release the encoded data of the image in order to release the browsing restriction on the image. The tag information is restored to the original content (step S103), and then the encoded data is transferred to the communication control unit 2005 and transmitted to the browsing request source device (step S106). Therefore, an image can be normally viewed by decoding and decompressing the received encoded data in the viewing request source apparatus.
[0091]
  On the other hand, when it is determined by the determination unit 2006 that the browsing request source apparatus does not have the browsing authority (No at Step S101), the control unit 2007 is an image whose browsing target is recorded in the storage unit B2002 (Step S104, No), the encoded data of the image is directly transferred to the communication control unit 2005 and transmitted to the browsing request source apparatus (step S106). If the browsing target is an image recorded in the storage unit A2002 (step S104, Yes), the control unit 2007 restricts the browsing of the image, so that the tag information rewrite processing unit 2003 uses the encoded data of the image. The tag information is rewritten (step S105), and then the encoded data is transferred to the communication control unit 2005 and transmitted to the browsing request source apparatus (step S106). Therefore, even when the browsing request source device decodes and decompresses the received encoded data, the image cannot be reproduced in its original form, and browsing is limited.
[0092]
  It should be noted that it is also possible to realize on the computer means and processing procedures related to image browsing restriction or browsing restriction release in the image processing apparatus 2000 of the present embodiment. A program for that purpose and a storage (recording) medium on which the program is recorded are also included in the present invention.
[0093]
  << Embodiment 3 >> FIG. 34 is a block diagram for explaining Embodiment 3 of the present invention. The image processing apparatus 3000 shown here transmits encoded image data to an external apparatus 3200 via a network 3100 such as the Internet.
[0094]
  The image processing device 3000 includes a storage unit 3001 in which encoded data (still image or moving image) is recorded, a communication control unit 3002 for communicating with the external device 3200 via the network 3100, and image browsing. It has a determination unit 3003 that determines whether or not the requested external device 3200 has a viewing authority, and a control unit 3004 that controls the entire device. In the encoded data of the image recorded in the storage unit 3001, tag information is rewritten to restrict browsing. Since the tag information rewriting method may be the same as that of the first embodiment, description thereof will not be repeated.
[0095]
  Next, the operation of the image processing device 3000 when an image browsing request is received from a certain external device 3200 will be described. FIG. 35 is a flowchart for the explanation.
[0096]
  In the image processing device 3000, the determination unit 3003 determines whether or not the external device 3200 that is the image browsing request source (hereinafter abbreviated as the browsing request source device) has the browsing authority (step S201). The determination method may be the same as in the second embodiment. When the determination unit 3003 determines that the browsing request source apparatus has the browsing authority (Yes in step S201), the control unit 3004, together with the encoded data of the image, information for releasing the browsing restriction, that is, Information indicating a method for restoring the tag information to the original content is transferred to the communication control unit 2005 and transmitted to the browsing request source device (step S202). On the other hand, when the determination unit 3003 determines that the browsing request source apparatus does not have the browsing authority (No in step S201), the control unit 3004 transfers only the code data of the image to the communication control unit 2005 to request browsing. Transmit to the original device (step S203).
[0097]
  As shown schematically in FIG. 34, the browsing request source apparatus includes a tag information restoration processing unit 3202, an image decompression unit 3203, and a display unit 3204 in addition to a communication control unit 3201 for performing communication with the image processing device 3000. . When the viewing request source apparatus has viewing authority, as described above, information for viewing cancellation is received from the image processing device 3000 together with the encoded data of the image. The browsing request source device, in accordance with this browsing cancellation information, tag information recovery processing unit3202After returning the tag information of the encoded data received in step 1 to the original content (the content before being rewritten due to viewing restrictions), the encoded data is decoded and expanded by the image expansion unit 3203, and the reproduced image data is displayed. A part 3204 is displayed. Therefore, the image can be browsed without restriction.
[0098]
  However, if the viewing request source apparatus does not have the viewing authority, only the encoded data of the image is received, and information for releasing the viewing restriction cannot be received. Therefore, normal image data cannot be reproduced and displayed.
[0099]
  It is also possible to implement on the computer means and processing procedures related to image browsing restriction or browsing restriction release in the image processing apparatus 3000 of the present embodiment. A program for that purpose and a storage (recording) medium on which the program is recorded are also included in the present invention.
[0100]
  In order to implement the present invention, encoded data of JPEG2000 or Motion-JPEG2000 is preferable. However, if it is possible to restrict viewing by rewriting the same tag information and canceling the viewing restriction by restoration, other formats can be used. Of course, the present invention can also be applied to encoded data..
[0101]
【The invention's effect】
  As is apparent from the above description, in the present invention, the image compression is performed in order to limit the browsing by rewriting the tag information of the encoded data of the image and to release the browsing limitation by returning the tag information to the original content. There is no need to make any changes to the encoding process and the decoding and decompression process. Accordingly, a standard configuration can be used as the encoding means or decoding expansion means. By selecting the content or method of rewriting the tag information, it is possible to place a very various form of viewing restrictions on the image. Rewriting or restoring tag information for restricting browsing or canceling it is a simple and time-consuming process, and can be easily executed by software. At any time after compression encoding of an image and without decoding / decoding the encoded data, the viewing restriction can be applied, released, or the viewing restriction method can be changed. .
[Brief description of the drawings]
FIG. 1 is a block diagram for explaining an algorithm of JPEG2000.
FIG. 2 is a diagram for explaining a two-dimensional wavelet transform.
FIG. 3 is a diagram for explaining a format of encoded data;
FIG. 4 is an explanatory diagram of a precinct and a code block.
FIG. 5 is a diagram illustrating an example of a packet and a layer.
FIG. 6 is a diagram illustrating an arrangement order of packets.
FIG. 7 is a diagram illustrating a configuration of a main header.
FIG. 8 is a diagram illustrating a configuration of a tile header.
FIG. 9 is a diagram showing a list of markers and marker segments.
FIG. 10 is a diagram showing a configuration of an SOT marker segment.
FIG. 11 is a diagram illustrating a configuration of an SIZ marker segment.
FIG. 12 is a diagram showing a configuration of a COD marker segment.
FIG. 13 is a diagram showing a configuration of a CRG marker segment.
FIG. 14 is a diagram showing a configuration of an RGN marker segment.
FIG. 15 is a block diagram for explaining the first embodiment of the present invention;
FIG. 16 is a schematic diagram for explaining an operation mode 1;
FIG. 17 is a schematic diagram for explaining an operation mode 2;
FIG. 18 is a schematic diagram for explaining an operation mode 3;
FIG. 19 is a schematic diagram for explaining an operation mode 4;
FIG. 20 is a schematic diagram for explaining an operation mode 5;
FIG. 21 is a schematic diagram for explaining an operation mode 6;
FIG. 22 is a schematic diagram for explaining an operation mode 7;
FIG. 23 is a schematic diagram for explaining an operation mode 8;
FIG. 24 is a schematic diagram for explaining an operation mode 9;
FIG. 25 is a diagram for explaining browsing restrictions due to rewriting of tile numbers.
FIG. 26 is a diagram for explaining browsing restrictions due to rewriting of an image size.
FIG. 27 is a diagram for explaining a viewing restriction by rewriting an offset position.
FIG. 28 is a diagram for explaining browsing restrictions due to rewriting of the bit shift amount in the ROI area;
FIG. 29 is a diagram for explaining browsing restrictions by rewriting the number of samplings in the horizontal and vertical directions.
FIG. 30 is a diagram illustrating an example of browsing restriction by rewriting tag information of a skipped frame.
FIG. 31 is a diagram illustrating an example of browsing restriction by rewriting tag information having different contents depending on a frame.
FIG. 32 is a block diagram for explaining the second embodiment of the present invention;
FIG. 33 is a flowchart for explaining the second embodiment;
FIG. 34 is a block diagram for explaining the third embodiment of the present invention;
FIG. 35 is a flowchart for explaining the third embodiment;
[Explanation of symbols]
1000 Input interface part
1001 Imaging unit
1002 Image compression unit
1003 Output interface section
1004 Tag information rewrite processing unit
1005 Tag information recovery processing section
1006 Storage unit
1007 Image decompression section
1008 Display unit
1009 Control unit
1010 Operation unit
2001 Memory part A
2002 Memory B
2003 Tag information rewrite processing part
2004 Tag information recovery processing part
2005 Communication control unit
2006 judgment part
3001 Storage unit
3002 Communication control unit
3003 Judgment part
3202 Tag information recovery processing section

Claims (18)

An image processing apparatus for processing an encoded data of an image conforming to JPEG2000, for image viewing limitations, have a tag information rewriting means for rewriting the tag information of the encoded data,
The tag information rewriting unit rewrites an Isot value of an SOT marker segment included in a tile header of the encoded data. An image processing apparatus for processing encoded data of an image compliant with JPEG2000, comprising tag information rewriting means for rewriting tag information of the encoded data for restricting image browsing,
  The tag information rewriting unit rewrites the Xsiz and Ysiz values of the SIZ marker segment included in the main header of the encoded data. An image processing apparatus for processing encoded data of an image compliant with JPEG2000, comprising tag information rewriting means for rewriting tag information of the encoded data for restricting image browsing,
  The tag information rewriting unit rewrites the XOsiz or YOsiz value of the SIZ marker segment included in the main header of the encoded data. An image processing apparatus for processing encoded data of an image compliant with JPEG2000, comprising tag information rewriting means for rewriting tag information of the encoded data for restricting image browsing,
  The tag information rewriting unit rewrites the SPrgn value of the RGN marker segment included in the main header or tile header of the encoded data. An image processing apparatus for processing encoded data of an image compliant with JPEG2000, comprising tag information rewriting means for rewriting tag information of the encoded data for restricting image browsing,
  The tag information rewriting unit rewrites a value related to color conversion in SGcod of a COD marker segment included in a main header or tile header of the encoded data. An image processing apparatus for processing encoded data of an image compliant with JPEG2000, comprising tag information rewriting means for rewriting tag information of the encoded data for restricting image browsing,
  The tag information rewriting means rewrites the Csiz value of the SIZ marker segment included in the main header of the encoded data. An image processing apparatus for processing encoded data of an image compliant with JPEG2000, comprising tag information rewriting means for rewriting tag information of the encoded data for restricting image browsing,
  The tag information rewriting unit rewrites the value of Xcrg (i) or Ycrg (i) of a CRG marker segment included in a main header of the encoded data. An image processing apparatus for processing encoded data of an image compliant with JPEG2000, comprising tag information rewriting means for rewriting tag information of the encoded data for restricting image browsing,
  The tag information rewriting unit rewrites the number of decomposition levels in the SPcod of a COD marker segment included in a main header or tile header of the encoded data. An image processing apparatus for processing encoded data of an image compliant with JPEG2000, wherein the tag information rewrites tag information of the encoded data to restrict image browsing Having information rewriting means,
  The tag information rewriting means rewrites the value of XRsiz (i) or YRsiz (i) of the SIZ marker segment included in the main header of the encoded data. An image processing method for processing encoded data of an image compliant with JPEG2000, comprising a tag information rewriting step of rewriting the tag information of the encoded data in order to restrict browsing of the image,
  The tag information rewriting step rewrites the Isot value of the SOT marker segment included in the tile header of the encoded data. An image processing method for processing encoded data of an image compliant with JPEG2000, comprising a tag information rewriting step of rewriting the tag information of the encoded data in order to restrict browsing of the image,
  The tag information rewriting step rewrites the Xsiz and Ysiz values of the SIZ marker segment included in the main header of the encoded data. An image processing method for processing encoded data of an image compliant with JPEG2000, comprising a tag information rewriting step of rewriting the tag information of the encoded data in order to restrict browsing of the image,
  The tag information rewriting step rewrites the XOsiz or YOsiz value of the SIZ marker segment included in the main header of the encoded data. An image processing method for processing encoded data of an image compliant with JPEG2000, comprising a tag information rewriting step of rewriting the tag information of the encoded data in order to restrict browsing of the image,
  The tag information rewriting step rewrites the SPrgn value of the RGN marker segment included in the main header or tile header of the encoded data. An image processing method for processing encoded data of an image compliant with JPEG2000, comprising a tag information rewriting step of rewriting the tag information of the encoded data in order to restrict browsing of the image,
  The tag information rewriting step rewrites a value related to color conversion in SGcod of a COD marker segment included in a main header or tile header of the encoded data. An image processing method for processing encoded data of an image compliant with JPEG2000, comprising a tag information rewriting step of rewriting the tag information of the encoded data in order to restrict browsing of the image,
  The tag information rewriting step rewrites the Csiz value of the SIZ marker segment included in the main header of the encoded data. An image processing method for processing encoded data of an image compliant with JPEG2000, comprising a tag information rewriting step of rewriting the tag information of the encoded data in order to restrict browsing of the image,
  The tag information rewriting step rewrites the value of Xcrg (i) or Ycrg (i) of the CRG marker segment included in the main header of the encoded data. An image processing method for processing encoded data of an image compliant with JPEG2000, comprising a tag information rewriting step of rewriting the tag information of the encoded data in order to restrict browsing of the image,
  The tag information rewriting step rewrites the number of decomposition levels in SPcod of a COD marker segment included in a main header or tile header of the encoded data. Image processing that processes encoded data of images compliant with JPEG2000 A tag information rewriting step for rewriting tag information of the encoded data in order to restrict browsing of images,
  The tag information rewriting step rewrites the XRsiz (i) or YRsiz (i) value of the SIZ marker segment included in the main header of the encoded data.

Images