JP2004180224A - Moving image communication system, moving image reproduction terminal, moving image distribution apparatus, and moving image reproducing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a moving image communication system, a moving reproduction terminal, a moving image distribution apparatus and a moving image reproducing method with which, for a program provided by a moving image distribution server, a scene that a user want to view can be reproduced slowly and the quality of the slow motion image is improved. <P>SOLUTION: The moving image reproduction terminal 200 comprises: a display means 206; a synchronizing means 209 that synchronizes a display timing of image data based on an information contained in the moving image data; a sound reproduction means 205; a command transmitting part 208; a CPU part 207; and an operation part 201. The moving image distribution server 100 comprises: a command analysis means 103 that analyzes a command of the moving image reproduction terminal 200; a searching means 106 that searches for a moving image data frame based on a time information contained in the command; and a data transmitting part 105 that transmits moving image data containing the time information corresponding to each image frame and that can change a transmission ratio of sound data to the moving image data. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image communication system having a moving image distribution server connected to a network, and a moving image reproduction terminal connected to the moving image distribution server via a wireless network to reproduce desired moving image data. The present invention relates to a moving image reproducing terminal, a moving image distribution device, and a moving image reproducing method.
[0002]
[Prior art]
2. Description of the Related Art A moving image communication system including a mobile phone device, which is one of the conventional moving image reproducing terminals, as a component, stores moving image data transmitted from a moving image distribution server or the like connected to a network. Playback on the display device of the terminal). Further, the conventional mobile phone device can only control fast forward, rewind, and pause. Further, the conventional mobile phone device can only take a method of receiving a still image when a high-quality image is required (for example, see Patent Documents 1 and 2).
[0003]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2000-253400 [Patent Document 2]
Japanese Patent Application Laid-Open No. 2000-253399
[Problems to be solved by the invention]
Therefore, in the conventional moving image communication system, the mobile phone device can only control the fast forward, rewind, or pause while the received stream is being reproduced, so that the user wants to see the program provided by the moving image distribution server. There was a problem that the scene could not be played back in slow motion.
[0005]
Also, in the conventional moving image communication system, when a moving image distribution server distributes an image to be reproduced in slow motion, a predetermined scene of predetermined content is encoded after being slowed down, so that the user can select a desired scene. There was a problem that slow playback could not be performed at the timing.
[0006]
Furthermore, in the conventional moving image communication system, there is a problem that the image quality is not so different from that in the normal reproduction even when the reproduction is performed in a slow manner, so that a high-quality slow image cannot be viewed.
[0007]
The present invention provides a moving image communication system, a moving image reproduction terminal, and a moving image reproduction method that can reproduce a scene that a user wants to see in a program provided by a moving image distribution server at a slow speed and can improve the image quality of the slow image. An object of the present invention is to provide a distribution device and a moving image reproducing method.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 provides a moving image distribution device connected to a network, and a moving image reproduction terminal connected to the moving image distribution device via a wireless network. In the moving image communication system, the moving image reproducing terminal includes: a data receiving unit that receives moving image data from the moving image distribution device; and a display unit that displays the moving image received by the data receiving unit. Instruction means for instructing slow playback of a moving image displayed on the display means, and command transmission for transmitting a slow playback command including time information when the instruction means instructs slow playback to the moving image distribution apparatus Means, a command receiving means for receiving a command transmitted from the moving image playback terminal, and a slow playback command A search unit that searches for moving image data based on time information included in the command when received, the moving image data and the slow reproduction moving image data corresponding to the time information searched by the search unit Data transmission means for transmitting to the moving image reproduction terminal.
By doing so, the user can operate the operation unit of the moving image reproduction terminal to perform slow reproduction of the desired portion of the moving image transmitted from the moving image distribution device and view it.
[0009]
The invention according to claim 2, wherein the data transmitting means transmits audio data and moving image data when transmitting moving image data corresponding to the time information and moving image data for slow reproduction to the moving image reproducing terminal. The transmission is characterized by changing the transmission ratio.
[0010]
The invention according to a third aspect is characterized in that the command transmission means transmits time information including n seconds before when the instruction means instructs slow reproduction in a slow reproduction command.
With this configuration, when the user operates the operation unit of the moving image reproduction terminal, slow reproduction can be performed from the scene n seconds before the operation.
[0011]
According to a fourth aspect of the present invention, the moving image data is composed of hierarchically encoded moving image data, and the moving image data for slow reproduction is transmitted in an extended portion of the hierarchically encoded moving image data. It is characterized by the following.
[0012]
According to a fifth aspect of the present invention, there is provided a moving image reproducing terminal for receiving moving image data from a moving image distribution device, a receiving unit for receiving moving image data from the moving image distribution device, and a moving image received by the receiving unit. Display means for displaying; instruction means for instructing slow reproduction of a moving image displayed on the display means; and a slow reproduction command including time information when the instruction means instructs slow reproduction. And transmission means for transmitting the data to the computer.
[0013]
According to a sixth aspect of the present invention, in the moving image distribution apparatus for transmitting moving image data to a moving image reproducing terminal, a storage unit for storing moving image data and moving image data for slow reproduction, Transmitting means for transmitting moving image data to the terminal, receiving means for receiving a command transmitted from the moving image reproducing terminal, and time information included in the command when the receiving means receives a slow reproduction command Searching means for searching for moving image data based on the search information, wherein the transmitting means reads, from the storage means, moving image data corresponding to the time information searched by the searching means and moving image data for slow reproduction. And transmitting the moving image to the moving image reproducing terminal.
[0014]
According to a seventh aspect of the present invention, in the moving image reproducing method for performing a slow reproduction of a moving image distributed from a moving image distribution device in a moving image reproducing terminal, the moving image reproducing terminal detects a slow reproduction instruction of the moving image. Transmits the slow playback command including the detected time information to the moving image distribution device, and the moving image distribution device receiving the slow reproduction command transmits the moving image corresponding to the time information included in the slow reproduction command. The data and the moving image data for slow reproduction are transmitted to the moving image reproducing terminal.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a moving image communication system according to an embodiment of the present invention will be described with reference to the drawings.
[0016]
FIG. 1 is a block diagram of a video communication system according to an embodiment of the present invention. The main moving image communication system includes a moving image distribution server (moving image distribution device) 100 connected to a network, and a moving image for reproducing desired moving image data by connecting to the moving image distribution server 100 via a wireless network. And an image reproducing terminal 200.
[0017]
The moving picture reproducing terminal 200 includes at least display means 206 for displaying a moving picture, network interface means 202 for transmitting and receiving data by connecting to a network, and image decoding for decoding the encoded moving picture data. Means 204; synchronizing means 209 for synchronizing the display timing of the image data decoded by the time information included in the moving image data; and audio decoding means 203 for decoding the received encoded audio information. Audio reproducing means 205 for reproducing the decoded audio information, a command transmitting section 208 for transmitting a command to the moving image distribution server 100, a CPU section 207, and an operation section 201 operated by a user.
[0018]
The moving image distribution server 100 includes a network interface unit 101 for connecting to a network, a command receiving unit 102 for receiving a command sent from the moving image reproducing terminal 200, a command analyzing unit 103 for analyzing the command, Search means 106 for searching for a moving image data frame whose temporal information matches based on the included time information, and hierarchically encoded moving image data 104 including time information corresponding to each image frame are transmitted. It has a data transmission unit 105 that can change the transmission ratio between the data and the moving image data 104.
[0019]
Next, the operation of the video communication system will be described. First, a user using the moving image reproduction terminal 200 operates the operation unit 201 to connect to the moving image distribution server 100 via the network interface unit 202. When the user operates the operation unit 201 to select the content of the desired moving image data, the moving image data transmitted from the moving image distribution server 100 is received by the network interface unit 202 of the moving image reproduction terminal 200. .
[0020]
Of the moving image data received by the network interface unit 202, audio encoded data is decoded by the audio decoding unit 203 and reproduced by the audio reproducing unit 205. Among the received moving image data, the image coded data is decoded by the image decoding unit 204, and is reproduced by the display unit 206 in synchronization with the time information included in the moving image data by the synchronization unit 209. You.
[0021]
If the user operates the operation unit 201 at a desired timing for a scene to be played back in slow motion during playback of the moving image data, the CPU unit 207 detects that a slow playback request operation has been performed. Next, the CPU unit 207 extracts the time information of the image frame currently being reproduced, creates time information n seconds ago from the time information, and sends the slow playback command storing the time information via the command transmission unit 208. To the moving image distribution server 100.
[0022]
The moving image distribution server 100 analyzes the command received via the network interface unit 101 and the command receiving unit 102 by the command analyzing unit 103. If the analyzed command is a slow reproduction request command, the command analysis unit 103 extracts time information included in the command. Next, the search unit 106 searches the moving image data 104 for a moving image frame corresponding to the time information. The data transmission unit 105 stops the transmission of the moving image data that has been transmitted so far, and starts transmission from the moving image frame searched by the search unit 106.
[0023]
Here, if the moving image data is MPEG or H.264. H.263, etc., when the data is stored in a compression scheme in which intra-frame coded data and inter-frame coded data are present, and the search result by the search unit 106 is a part of the inter-frame coded data Is provided by providing the following configuration in the moving image distribution server 100. That is, the search unit 106 also searches for nearby intra-frame encoded data, and provides an image decoding unit in the moving image distribution server 100, and the image decoding unit decodes up to the searched inter-frame encoded data. Then, by performing intra-frame encoding on the frame again, it is possible to transmit data from an exactly designated frame.
If there is no need to reach that point, it is sufficient to search for the nearest intra-frame encoded data from the searched intra-frame encoded data portion, and transmit from there.
[0024]
The data transmission unit 105 deletes the audio frame from the image data that has been transmitted so far, and starts transmitting the moving image data including the extended part of the hierarchized moving image encoded data. At this time, the time information included in the image frame is rewritten so that the moving image reproducing terminal 200 can perform the reproduction at a slow speed. The time information indicates a display interval of each image frame. By increasing the display interval indicated by the time information, the moving image reproducing terminal 200 can perform slow reproduction of the received moving image.
[0025]
In addition, since the moving image distribution server transmits moving image data including the extended part of the hierarchized moving image encoded data, the moving image reproduction terminal 200 can perform smooth slow reproduction without dropping frames.
At this time, the data sending unit 105 can send extra image data of the bit rate corresponding to the deleted audio frame, so that it is possible to send higher quality image data.
[0026]
Next, the relationship between moving image data and time information will be described in detail. FIG. 2 is a diagram showing a relationship between moving image data and time information in the moving image communication system. Normally, when moving image data is being reproduced, image data is transmitted as shown by image data 303 during normal reproduction, and time information 304 during normal reproduction is provided as time information corresponding to this image data. Will be added. In this example, the moving image data reproduced at 2 fps during normal reproduction is shown, but the present invention is not limited to this.
[0027]
At the time of the slow reproduction, the image data 301 added at the time of the slow reproduction obtained by the hierarchical encoding is inserted between the image frames of the image data 303 at the time of the normal reproduction in a complementary manner. At this time, as shown in FIG. 2, the time information is complemented by m (m is an integer of 1 or more) frames. When the frame rate at the time of reproduction is constant, the moving image reproduction terminal 200 performs slow reproduction at the same frame rate by rewriting the time information as shown by the time information 302 at the time of slow reproduction. It becomes possible.
[0028]
FIG. 3 is a diagram showing a transmission data format corresponding to a time axis in the moving picture communication system of the present embodiment. In FIG. 3, the frame numbers of the image frames correspond to those in FIG. 2, and this example shows an example in which the slow reproduction is performed at 1/3 times.
[0029]
During normal reproduction, as shown by transmission data 401 during normal reproduction, image data and audio data to be transmitted during normal reproduction are transmitted. At the time of slow reproduction, as shown by transmission data 402 at the time of slow reproduction, transmission is performed so as to complement the frame of the extended portion of the hierarchically encoded image data between frames of image data transmitted at the time of normal reproduction. At this time, since the audio data cannot be made slow, the transmission of the audio data may be deleted.
[0030]
FIG. 4 is a block diagram showing a configuration when real-time distribution is performed in the video communication system according to the present embodiment. The moving image reproducing terminal 200 is the same as that shown in FIG. The main difference between the moving image distribution server 500 of FIG. 4 and the moving image distribution server 100 of FIG. 1 is that the moving image distribution server 500 is provided with a real-time encoder 502 and moving image buffers 501a and 501b.
[0031]
When performing real-time distribution, the real-time encoder 502 performs hierarchical coding of a moving image in real time, and temporarily stores it in the moving image buffers 501a and 501b. At the time of normal reproduction, the data transmission unit 505 transmits only the image frames used at the time of normal reproduction from the data stored in the moving image buffer 501a. The moving image buffers 501a and 501b always store the image data up to n seconds before including the layered code data in order to cope with the slow reproduction up to n seconds before.
[0032]
When the command receiving unit 504 receives the slow reproduction command and the command is analyzed by the command analyzing unit 506, the searching unit 507 searches the moving image buffer 501a for a frame corresponding to the time information. The data transmission unit 505 fetches the corresponding image frame from the moving image buffer 501a including the hierarchical coded data from the search result of the search unit 507, and transmits it.
[0033]
As for the real-time encoded image data during slow reproduction, only the latest data of n seconds before is always accumulated in the moving image buffer 502b. When returning to normal reproduction after the end of the slow reproduction, the data transmission unit 505 uses the data stored in the moving image buffer 501b. As a result, slow reproduction can be performed even during real-time distribution.
[0034]
As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to the embodiments, and may include a design change or the like without departing from the gist of the present invention.
[0035]
【The invention's effect】
As described above, according to the present invention, it is possible for a user to slowly reproduce a desired scene while a moving image reproducing terminal receives and reproduces moving image data transmitted from a moving image distribution device. A moving image communication system, a moving image reproducing terminal, a moving image distribution device, and a moving image reproducing method capable of improving the image quality during slow reproduction.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a video communication system according to an embodiment of the present invention.
FIG. 2 is a diagram showing a relationship between moving image data and time information in the moving image communication system according to the first embodiment;
FIG. 3 is a diagram showing a transmission data format corresponding to a time axis in the moving image communication system according to the first embodiment.
FIG. 4 is a block diagram showing a configuration when real-time distribution is performed in the video communication system according to the embodiment.
[Explanation of symbols]
100 video distribution server (video distribution device)
101 network interface unit 102 command receiving unit 103 command analyzing unit 104 moving image data 105 data sending unit 106 searching unit 200 moving image reproduction terminal 201 operation unit 202 network interface unit 203 audio decoding unit 204 image decoding unit 205 audio reproduction unit 206 Display unit 207 CPU unit 208 Command sending unit 209 Synchronizing unit 301 Image data 302 added at the time of slow playback Time information 303 at the time of slow playback 303 Image data at the time of normal playback 304 Time information 401 at the time of normal playback Send data 402 at the time of normal playback Transmission data 500 at the time of slow reproduction Moving image distribution server 501a (real time distribution is possible) Moving image buffer 501b Moving image buffer 502 Real time encoder 503 Network interface Face portion 504 commands the receiving unit 505 data transmission unit 506 the command analysis unit 507 search means

Claims (7)

In a moving image communication system including a moving image distribution device connected to a network, and a moving image reproduction terminal connected to the moving image distribution device via a wireless network,
The video playback terminal,
Data receiving means for receiving moving image data from the moving image distribution device,
Display means for displaying a moving image received by the data receiving means,
Instructing means for instructing slow playback of a moving image displayed on the display means,
Command transmission means for transmitting a slow reproduction command including time information when the instruction means instructs slow reproduction to the moving image distribution device,
The moving image distribution device,
Command receiving means for receiving a command transmitted from the video playback terminal,
Search means for searching for moving image data based on time information included in the command when the command receiving means receives a slow playback command,
A moving picture communication system comprising: moving picture data corresponding to the time information searched by the search means; and data transmitting means for sending moving picture data for slow reproduction to the moving picture reproducing terminal. The data transmission means, when transmitting the moving image data corresponding to the time information and the moving image data for slow reproduction to the moving image reproducing terminal, transmits the moving image data while changing the transmission ratio between the audio data and the moving image data. The moving image communication system according to claim 1, wherein: 2. The moving image communication system according to claim 1, wherein the command transmission unit transmits the time information n seconds before the instruction unit instructs the slow reproduction, with the time information included in the slow reproduction command. 2. The moving image data according to claim 1, wherein the moving image data is composed of hierarchically encoded moving image data, and the moving image data for slow reproduction is transmitted in an extended part of the hierarchically encoded moving image data. Video communication system. In a moving image reproducing terminal that receives moving image data from a moving image distribution device,
Receiving means for receiving moving image data from the moving image distribution device;
Display means for displaying a moving image received by the receiving means,
Instructing means for instructing slow playback of a moving image displayed on the display means,
A moving image reproducing terminal, comprising: transmitting means for transmitting, to the moving image distribution device, a slow reproduction command including time information when the instruction means instructs slow reproduction. In a moving image distribution device that transmits moving image data to a moving image reproduction terminal,
Storage means for storing moving image data and moving image data for slow reproduction,
Transmitting means for transmitting moving image data to the moving image reproducing terminal,
Receiving means for receiving a command transmitted from the video playback terminal,
Search means for searching for moving image data based on time information included in the slow playback command when the receiving means receives the slow playback command,
The transmitting means reads out moving image data corresponding to the time information searched by the search means and moving image data for slow reproduction from the storage means and transmits the read moving image data to the moving image reproduction terminal. Delivery device. In a moving image reproduction method for performing slow reproduction of a moving image distributed from a moving image distribution device on a moving image reproduction terminal,
When the moving image playback terminal detects a slow playback instruction of a moving image, the slow playback command includes the detected time information in the slow playback command, transmits the slow playback command to the moving image distribution device, and receives the slow playback command. A moving image reproducing method, wherein the apparatus transmits moving image data corresponding to time information included in the slow reproduction command and moving image data for slow reproduction to a moving image reproduction terminal.

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