JP2009135977A - Image distribution method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image distribution method with which high-quality still picture data can be distributed to a client of a request source via a network. <P>SOLUTION: In step S1, S2, a moving image playback request is received from a client connected via a network. In step S5, in response to the moving image playback request, a moving image signal recorded on a recording medium is played back and transmitted to the client via the network. In step S6, a still image creation request containing time information of the moving image signal in prescribed timing is received from the client. In step S7, the moving image signal at a time position corresponding to the time information is played back to create a still image. In step S8, the still image is transmitted to the client. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image distribution method for distributing image data to a client via a network.

  2. Description of the Related Art Conventionally, network-compatible cameras that distribute image data to clients via a network such as the Internet are known (see, for example, Patent Documents 1 and 2). In Patent Document 1, real-time moving image data obtained by photographing with a camera is converted into data that can be compressed and transmitted by a moving image data distribution unit, and the converted data is transmitted from a mobile terminal to a server via a base station. In addition, a configuration is disclosed in which distribution from a server to a plurality of clients via a network is disclosed.

  On the other hand, in Patent Document 2, when a non-interlaced frame image is generated from an interlaced image obtained by an interlaced output imaging unit, a moving object detection unit detects a moving object of a subject based on image data from the imaging unit. The image data selection means determines whether the image data supplied from the imaging means is still image data or moving image data based on the detection output from the moving object detection means, and the subject is a stationary object or moving object. There has been disclosed a network-compatible camera configured to automatically switch between a frame image and a field image according to the above.

JP 2002-027452 A JP 2003-259175 A

  However, the conventional camera described in Patent Document 1 cannot transmit image data with an image quality that exceeds the capacity of the network that transmits the image data, and particularly transmits still image data with high image quality in response to a still image request from the client. Can not do it.

  Further, with the conventional camera described in Patent Document 2, moving image data and still image data can be selected and distributed to the client via the network. When still image data is distributed, frame image data is selected. Although the field image data is transmitted with higher image quality than when the field image data is transmitted, still image data with higher image quality than the frame image cannot be transmitted.

  Furthermore, in the conventional cameras described in Patent Documents 1 and 2, any one scene desired by the client in the moving image data distributed from the camera having the server function to the client via the network, Cannot be delivered from the camera as a still image file.

  The present invention has been made in view of the above points. High-quality still image data is generated via a network rather than generating a still image signal by itself based on a moving image distributed by a client in response to a request from the client. An object of the present invention is to provide an image delivery method that can be delivered to a requesting client.

  Another object of the present invention is to provide an image distribution method capable of distributing moving image data to a client and distributing a scene of the moving image requested from the client that has received the moving image data as a still image file. There is to do.

  In order to achieve the above object, the present invention provides a first reception step of receiving a video playback request from a client connected via a network, and a recording in response to the video playback request received in the reception step. A first transmission step of reproducing a moving image signal recorded on a medium and transmitting the same to the client via the network; and the first transmission step transmitted to the client and displayed on the client side Second reception for receiving a still image creation request including time information of the moving image signal at the predetermined timing from the client when it is requested to create a still image at a predetermined timing of the moving image signal Corresponding to the time information in response to the still image creation request received in the step and the second receiving step. A reproduction step for reproducing the moving image signal at a predetermined time position, a still image generation step for generating a still image based on the moving image signal reproduced in the reproduction step, and a still image generation step. And a second transmission step of transmitting the still image to the client via the network.

  The video camera according to the present embodiment is a video camera having a server function connectable to a network, a recording function of a moving image signal obtained by photographing on a recording medium, and a reproducing function of the recording medium. Connecting means for connecting to the client via the network and enabling the two-way communication between clients, and when the connection means receives a video delivery request from the client, the video played from the recording medium according to the video delivery request A moving image transmitting means for transmitting an image signal or a moving image signal being photographed to the client via the connection means, and when a still image distribution request is received from the client via the connection means, recording is performed according to the still image distribution request. A still image signal is created based on the moving image signal reproduced from the medium or the moving image signal being shot, and the client is connected via the connection means. It is configured to have a still image creation and transmission means for transmitting to the bets.

  In this embodiment, when there is a still image distribution request from a client via a network, when the still image distribution request is a still image distribution request based on a moving image signal recorded on the recording medium, A still image signal is generated from the reproduced moving image signal and transmitted to the client. When the still image distribution request is a still image distribution request based on the moving image signal being captured, the captured moving image signal A still image signal can be created from the image and transmitted to the client.

  Also, in the present embodiment, the still image creation and transmission unit described above detects the recording position information of the recording medium added to the still image distribution request, and the recording position obtained by reproducing the recording medium Recording position search means for searching for the recording position of the recording medium whose information matches the recording position information detected by the detection means, and playback for starting playback of the recorded moving image signal of the recording medium from the recording position searched by the recording position search means Means, a still image creation means for creating a still image based on the moving image signal reproduced by the reproduction means, and a transmission means for supplying the created still image to the connection means and transmitting it to the client.

  In this embodiment, when a client views a playback moving image on a distributed recording medium and requests a still image of an arbitrary one-screen moving image, the recording position information of the recording medium is included in the still image distribution request. Therefore, when the recording position information is detected, the search start position of the recording medium is set to the position indicated by the detected recording position information, and playback is started from the recording position searched for the recording medium. A still image signal created based on the moving image signal can be transmitted to the client.

  According to the present invention, since the still image signal created from the moving image signal is transmitted to the client based on the still image distribution request from the client, the still image signal itself is generated based on the moving image signal distributed by the client. It is possible to provide a high-quality still image to the client as compared with the case of creating the image.

  Further, according to the present invention, when a client views a playback moving image on a distributed recording medium and requests a still image of an arbitrary one-screen moving image, the recording position of the recording medium is included in the still image distribution request. When the recording position information is detected, the search for the recording medium is performed, and the still image signal created based on the moving image signal reproduced from the recording position searched for the recording medium is searched. Since it is sent to the client, it can send any one-screen still image signal requested by the client in the moving image, and the client can view the one-screen still image arbitrarily selected by the client with high quality. be able to.

It is a block diagram which shows the video camera of one Embodiment. It is a system configuration diagram of an example of an image distribution system. It is a flowchart for operation | movement description of one Embodiment. It is a figure which shows an example of the screen of the client at the time of moving image reception. It is a figure which shows an example of the screen of the client at the time of still image reception.

  Next, a mode for carrying out the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of an embodiment of a video camera for realizing the image distribution method of the present invention, and FIG. 2 is a system configuration diagram of an example of an image distribution system to which the video camera according to the present invention is applied. First, the image distribution system in FIG. 2 will be described. The video camera 1 according to the present embodiment is a camera-integrated VTR having a Web server function connectable to a network 4 and a recording medium for recording a video signal obtained by photographing. Both are connected to a network 4 such as the Internet via a modem 3 that performs modulation / demodulation operation, and further to a personal computer (hereinafter abbreviated as PC) 7 via a modem 5 that performs modulation / demodulation operation from the network 4 and a router 6 that performs path selection. Connected in the opposite direction.

  Here, the video camera 1, the router 2, and the modem 3 are disposed at arbitrary locations such as in the home, and the modem 5, the router 6, and the PC 7 are disposed at arbitrary locations outside the home. This image distribution system will be described briefly. The moving image data is distributed from the video camera 1 to the client PC 7 via the router 2, the modem 3, the network 4, the modem 5, and the router 6 to display the moving image. Then, the client is allowed to select any one of the moving images displayed on the screen of the PC 7. The client PC 7 transmits the selected still image request for one screen to the video camera 1 via the router 6, the modem 5, the network 4, the modem 3, and the router 2.

  Then, the video camera 1 creates a one-screen still image file selected by the client based on the received still image request, and distributes it to the PC 7 via the network 4 or the like. As a result, the PC 7 can view still images of higher quality than still images created by itself based on the received moving image data.

  Next, the configuration of an embodiment of a video camera according to the present invention will be described in detail with reference to FIG. First, an operation at the time of recording a moving image taken by a camera will be described. Incident light from a moving subject is imaged on an image sensor 12 through an optical system 11, and is photoelectrically converted here, for example, a total of two channels of image signals corresponding to each divided screen when one screen is divided into two. Is then supplied to the AFE block 13, where each channel is improved in S / N by correlated double sampling (CDS), level adjustment by automatic gain control operation, and A / D conversion operation by A / D conversion operation. After being subjected to processing such as / D conversion, it is supplied to the image processing circuit 14 as a digital video signal and synthesized into an image of one screen.

  Further, the image processing circuit 14 is supplied with a clock signal having a constant frequency oscillated and output by an oscillator (OSC) 15, and generates a clock used for CDS and A / D conversion of the AFE block 13 based on this clock signal. This is supplied to the AFE block 13, and a vertical drive signal necessary for the image sensor 12 is generated and supplied to the image sensor 12. The horizontal drive signal of the image sensor 12 is supplied from the AFE block 13.

  The one-screen digital video signal (video signal) output from the image processing circuit 14 is supplied to a camera / JPEG encoder 16, where predetermined camera signal processing is performed, and finally a digital video camera (DVC). ) The image size is converted into a moving image of effective pixels conforming to the standard and output. The video encoder / decoder 17 outputs the video signal supplied from the camera / JPEG encoder 16 as it is and supplies it to the DV codec 18.

  The DV codec 18 applies compression processing and shuffling processing based on the DV standard to the input video signal, adds various control data such as tracking information, time code, date and time information, and the audio selector / microphone amplifier 19. A / D conversion is added to the audio signal input from the signal, and an error correction code is further added to generate a DV format signal, which is then modulated into a signal format suitable for recording and then supplied to the DVC deck 20; Here, recording is performed on a magnetic tape based on a known helical scanning recording / reproducing mechanism using a rotating head.

  At this time, the video encoder / decoder 17 outputs characters necessary for device operation with respect to the input video signal from the on-screen display (OSD) 21 and internally synthesizes the standard format (NTSC format etc.) video signal. And is output to a display device (view finder, liquid crystal display device, etc.) 22 for displaying the main body and also output to the outside as a video signal. The sound collected by the microphone 23 is acoustic-electrically converted by the microphone 23 and then supplied to the DV codec 18 after gain adjustment by the sound selector / microphone amplifier 19. As described above, the DVC is added together with the moving image. Recording is performed on the magnetic tape by the deck 20.

  The system CPU (central processing unit) 24 is configured to control the power supply circuit (REG) 27 based on data from a user interface (UI) 25 such as operation switches and sensors, and a clock signal from the clock circuit (RTC) 26. The other blocks are centrally controlled by a control signal of a microcomputer (DSC) 28 and a signal line (not shown).

  Next, the reproducing operation of the recording signal on the magnetic tape will be described. The signal reproduced from the magnetic tape in the DVC deck 20 is demodulated and error-corrected by the DV codec 18, and the reproduced moving image signal is subjected to expansion processing and deshuffling processing based on the DV standard, and then output to the camera / JPEG encoder 16 once. Is done. The reproduced audio signal is D / A converted by the DV codec 18, supplied to the audio selector / microphone amplifier 19, amplified, and then subjected to electro-acoustic conversion by the speaker 29 to be sounded.

  The camera / JPEG encoder 16 performs zooming, still processing, and the like on the input reproduction moving image signal as necessary, and then outputs to the video encoder / decoder 17, and from this, a moving image tape photographed by the camera In the same manner as in the recording mode, the image is output to the display unit 22 or the outside and viewed.

  It should be noted that, during the same operation as the camera moving image tape recording mode or during tape playback, it is also possible to record moving images and audio signals to the SD card (memory card) 31. For example, in the camera moving image tape recording mode, a moving image signal is output from the camera / JPEG encoder 16 to the DSC 28. An audio signal is input from the audio selector / microphone amplifier 19 to the audio ADC / DAC 30, where it is A / D converted and then output to the DSC 28.

  The DSC 28 compresses moving image signals such as MPEG4 after conversion to a predetermined size / frame rate that can be handled by a PC tool, and can also handle audio signals using a PC tool. After compression after conversion to the sampling rate and the number of bits, the compressed moving image data and audio data are collected into one file and written to the SD card 31. At this time, the read only memory (ROM) 32 connected to the DSC 28 is used as a program code, and the synchronous dynamic random access memory (SDRAM) 33 is used as an image buffer and a work area.

  During playback of the SD card 31, is moving image data and audio data recorded on the SD card 31 separated and expanded by the DSC 28, and is the moving image signal displayed on the display 22 via the video encoder / decoder 17? Alternatively, the audio signal is output to the outside, and the audio signal is generated by the speaker 29 via the audio selector / microphone amplifier 19 after D / A conversion by the audio ADC / DAC 30.

  Also, still images can be recorded on the SD card 31 when performing the same operation as the camera video tape recording mode or during tape playback. For example, the video signal is taken into the camera / JPEG encoder 16 in the same manner as in the camera video tape recording mode, and JPEG compression is performed here. Thereafter, the JPEG compressed data is transferred to the image processing circuit 14 via the external bus, and further transmitted to the DSC 28 by high-speed serial transfer. Then, the DSC 28 converts the received JPEG data into a file and records it on the SD card 31.

  When playing back a still image from the SD card 31, the JPEG data read from the SD card 31 is JPEG decompressed by the DSC 28, and then converted to a size that conforms to the standard television standard before the video encoder. / Displayed on the display 22 via the decoder 17 or output to the outside as a video signal.

  Next, using the video camera 1 of the present embodiment that performs the above-described recording / reproducing operation, a moving image is presented to a client connected via a network, and a scene of the moving image arbitrarily selected by the client The operation of presenting the still image data to the client will be described in detail with reference to the flowchart of FIG.

  First, instead of the SD card 31 connected to the SDIO interface (I / F) of the DSC 28, when the wireless LAN card 34 is connected to the SDIO interface (I / F) as shown in FIG. 1 corresponds to the PC 7), and the video camera 1 is connected via the network (step S1 in FIG. 3). In the DSC 28, a TCP / IP protocol stack and a Web server are mounted, and the video camera 1 can be controlled by access from the PC 35 (7).

  In this state, a URL (Uniform Resource Locator), a user name, and a password on the network 4 of the video camera 1 are input from the PC 7 as a client at an arbitrary timing, and the modem 5, the router 6 and the network 4, and the modem 3 and the router. 2 accesses the video camera 1.

  As a result, the display screen 41 of the PC 7 (35) includes a streaming display unit 42 for displaying the received image, a camera operation unit 43 for remotely controlling the video camera 1, and a screen as shown in FIG. Web pages stored in the ROM 32 connected to the DSC 28 of FIG. 1, such as a display unit 44 showing the contents, a moving image size display unit 45, and a bit rate display unit 46, are displayed. The camera operation unit 43 includes a stop button 431, a rewind button 432, a playback button 433, a fast forward button 434, a button 435 for requesting a moving image to be captured by the video camera 1, and a moving image to be displayed as a video camera. 1 includes a button 436 for requesting one reproduced from a tape, a button 437 for requesting output of a still image, and the like.

  After the client clicks the button 436 labeled “tape” in the display screen 41 of the PC 7 (35) and issues a control command for switching the input source of the video camera 1 from the camera signal input to the tape signal input. When the playback button 433 is clicked, a video playback request is transmitted to the video camera 1 via the network 4 (step S2 in FIG. 3).

  When the video camera 1 receives the video playback request, it outputs a tape playback video mode command from the DSC 28 to the system CPU 24, whereby the system CPU 24 determines whether a magnetic tape is loaded in the DVC deck 20 (step in FIG. 3). S3) If the magnetic tape is not loaded, the client is notified that there is no tape (step S4 in FIG. 3), but when the magnetic tape is loaded, the DVC deck 20 performs the above-described reproduction operation. (Step S5 in FIG. 3).

  That is, for example, a signal reproduced for 10 seconds from the magnetic tape in the DVC deck 20 is demodulated and error-corrected by the DV codec 18, and the reproduced moving image signal is subjected to expansion processing and deshuffling processing based on the DV standard. The data is output once to the encoder 16 and then input to the DSC 28. The DSC 28 compresses the input playback video signal with the size set on the Web page, and uses the SDRAM 33 as a buffer together with auxiliary information such as the codec type, image size, and bit rate, to the PC 35 (7). Send it out as a video stream.

  The PC 35 (7) reproduces the received moving image stream using moving image software, and as shown in FIG. 4, the moving image of the moving image stream transmitted from the video camera 1 is displayed on the streaming display unit 42 of the screen 41 of the display. Is displayed. When the user of the PC 35 (7) sees this streaming playback moving image and there is an image of one scene that he / she likes as a still image, for example, the user clicks the button 437 with the cursor at the timing of the arbitrary scene. When a still image is designated by the method, the PC 7 (35) obtains time information from the moving image portion at the designated time point, generates a still image creation request with the obtained time information added thereto, and the video camera 1 via the network 4 (Step S6 in FIG. 3). Note that the above time information indicates data that is added and packetized separately from the video signal and the audio signal on the payload of the moving picture stream packet.

  When the video camera 1 receives the above still image creation request, the DSC 28 notifies the system CPU 24 of the time information included therein, and the system CPU 24 controls the DVC deck 20 to reproduce the received time information and magnetic tape. The magnetic tape is rewound while comparing with the received time code, and the reproduction position of the magnetic tape is advanced to just before the received time information, and the reproduction of the magnetic tape is started from the position of the received time information.

  The video signal reproduced from the magnetic tape is demodulated and error-corrected by the DV codec 18 and further subjected to expansion processing and deshuffling processing based on the DV standard, and then taken into the camera / JPEG encoder 16 and JPEG compressed. Thereafter, the JPEG compressed data is transferred to the image processing circuit 14 via the external bus, and further transmitted to the DSC 28 by high-speed serial transfer. Then, the DSC 28 creates a still image filed from the received JPEG data (step S7 in FIG. 3), and uses the still image file as a client PC 35 via the wireless LAN card 34 and the network 4 using the SDRAM 33 as a buffer. (7) (step S8 in FIG. 3).

  Thereby, as shown in FIG. 5, the received still image is displayed on the still image display unit 51 that occupies most of the screen 41 of the display of the PC 7 (35). The screen 41 also displays Web pages stored in the ROM 32 connected to the DSC 28 in FIG. 1, such as the display unit 52 indicating that it is a still image and the size display unit 53 of the still image. After the still image is displayed, the video camera 1 updates the still image or the moving image from the client, which is performed by clicking the update button 54 or the moving image switching button 55 on the display screen 41 of the PC 7 (35) in FIG. Waiting for the next request to switch to (step S9 in FIG. 3).

  As described above, in the present embodiment, since the client receives high-quality still image data created by the video camera 1 in accordance with the client's request, the still image created by itself based on the moving image data received by the client. It is possible to view still images of higher quality than images, and to view still images of an arbitrary scene designated by the client from the received moving images.

  Note that the present invention is not limited to the above-described embodiment, and for example, it is possible to perform moving image distribution during shooting by a camera and a still image request based thereon. In this case, while a moving image being photographed is being displayed on the client's PC screen, if a still image creation request for an arbitrarily selected scene is received from the client, the still image creation request is sent via the DSC 28 to the system CPU 24. Since the system CPU 24 is currently outputting to the client the moving image signal currently being shot by the camera, the still image is transferred to the SD card 31 during the same operation as the camera moving image tape recording mode described above. In the same way as the operation when the image is recorded, the video signal being shot at the time of receiving the still image creation request is taken into the camera / JPEG encoder 16, and the JPEG compression data obtained by performing the JPEG compression here is transferred to the external bus. To the image processing circuit 14 and further to the DSC 28 by high-speed serial transfer.

  The DSC 28 creates a still image filed from the received JPEG data, and transmits the still image file to the client via the wireless LAN card 34 and the network 4 using the SDRAM 33 as a buffer.

  By the way, when a client requests a still image, it is assumed that the angle of view is changed in response to a request to increase the subject or to make the image including the background during the still image creation period immediately after the still image request. . In this case, it is conceivable that an image with low quality is created by transmitting an image in the middle of zooming or creating a still image from the image in the middle of zooming. In order to avoid these, when zooming is performed during a predetermined period immediately after a still image request is received from the client, a still image may be created after the zoom operation is completed. Furthermore, a configuration may be adopted in which a plurality of types of shooting angles of view are prepared in advance, a desired angle of view is selected from among them, a video camera is set at the position of the angle of view, and a still image is created.

  Further, instead of the PC 7, the modem 5 and the router 6, a mobile phone terminal or a PDA (simple portable information terminal) may be used. Furthermore, in the present invention, it is also possible to transmit an image signal being shot by the video camera 1 or an external input video signal of the video camera 1 at the request of the client. In the above embodiment, the video signal (moving image signal) obtained by photographing the subject has been described as being recorded on a magnetic tape or an SD card. However, the present invention is not limited to this. Video information can be recorded and reproduced on any recording medium capable of recording and reproducing video information such as optical disks, magnetic disks, and semiconductor memories.

1 Video camera 2, 6 Router 3, 5 Modem 4 Network 7, 35 Personal computer (PC)
DESCRIPTION OF SYMBOLS 11 Optical system 12 Image pick-up element 14 Image processing circuit 16 Camera / JPEG encoder 17 Video encoder / decoder 18 DV codec 19 Audio selector / microphone amplifier 20 DVC deck 23 Microphone 24 System CPU (central processing unit)
28 DSC (microcomputer)
29 Speaker 30 Audio ADC / DAC
31 SD card 32 ROM storing web pages
34 Wireless LAN card

Claims (2)

A first receiving step of receiving a video playback request from a client connected via a network;
A first transmission step of reproducing a moving image signal recorded on a recording medium and transmitting it to the client via the network in response to the moving image reproduction request received in the reception step;
When it is requested to create a still image at a predetermined timing of the moving image signal transmitted to the client and displayed on the client side in the first transmission step, the client performs the predetermined timing. A second reception step of receiving a still image creation request including time information of the moving image signal at
In response to the still image creation request received in the second reception step, a reproduction step of reproducing the moving image signal at a time position corresponding to the time information;
A still image creating step for creating a still image based on the moving image signal reproduced in the reproducing step;
And a second transmission step of transmitting the still image created in the still image creation step to the client via the network. The moving image signal recorded on the recording medium is a compressed moving image signal,
The reproduction step includes a step of performing an extension process on the moving image signal at a time position corresponding to the time information,
The image distribution method according to claim 1, wherein the still image creating step creates a still image based on the moving image signal subjected to the decompression process in the reproduction step.

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