JP2002232860A - System and method for distributing contents, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the distribution service of video contents through a network while one video contents are preserved. SOLUTION: The moving picture distributing system is provided with an application server 4 having a WWW server function part 44 for receiving the discharge request of a moving picture (video contents) from a user through the Internet 3, a retrieval processing part 43 for retrieving the moving picture from an MPEG-2 data-base 51 accumulating the moving picture of a prescribed compression system (MPEG-2 system) based on the received discharge request, and a transcoder 60 for distributing the retrieved moving picture while it is converted into a system that can be distributed by the Internet 3 at high speed (converted from the MPEG-2 system into MPEG-4 system).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an international standard system for coding moving images, for example, MPEG1 and M2 of ISO / IEC JTC1 / SC29 / WG11.
The present invention relates to a content distribution system, a content distribution method, and a program for converting (transcoding) moving image data compressed by PEG-2, MPEG-4, or the like into another system and distributing them.

2. Description of the Related Art Generally, broadcast stations and the like store video contents in digital form in order to secondary use the produced and broadcasted video contents.

Conventionally, video contents are stored in the MPEG-2 format used for broadcasting and DVDs.

[0003] As a business object of such secondary use of video contents, a distribution service via the Internet is currently being studied.

By the way, MPEG-2 format data is
In the currently widespread communication environment, it is heavy, for example, MPEG-
In order to refer to the two types of video content on the Internet, the line capacity of the Internet is insufficient due to the high bit rate.

[0005] Therefore, it is conceivable to convert MPEG-2 format video content into a format suitable for distribution on the current Internet, for example, MPEG-4 format and distribute it.

[0006] Therefore, in order to provide such a moving image distribution service, it is necessary to distribute the video content in real time in response to a request from the user. MPE
It is necessary to prepare G-4 format video content at a moving image distribution source such as a broadcasting station.

[0007] However, this requires a storage location for each video content and makes it difficult to manage synchronization when content editing or the like occurs.

As described above, when the created video content is used for secondary use, conventionally, it is necessary to prepare video content for storage and video content for distribution. For this reason, there are problems that the registration requires a lot of trouble, extra resources of the database are required, and management becomes difficult in terms of storage of the video contents.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and a content distribution system, a content distribution method, and a program capable of realizing a video content distribution service via a network while storing one video content. It is intended to provide.

Another object of the present invention is to provide a content distribution system, a content distribution method, and a program capable of realizing a content lending service using a network.

According to a first aspect of the present invention, there is provided a content distribution system, comprising: means for receiving a content delivery request from a user through a network; A storage unit for storing the compressed content; a search unit for searching for the corresponding content from the storage unit based on the received payout request; and a request for converting the content searched by the search unit into a second compression format. It is characterized by having a compression format conversion and distribution means for distributing to the original.

According to a second aspect of the present invention, there is provided a content distribution system for receiving a content lending request from a user via a network, storing the content compressed in a first compression format, and receiving the lending request. Search means for searching the content from the storage means based on the storage means, and compression format conversion for adding the rental condition information while delivering the content searched by the search means to the second compression format and delivering the information to the request source And distribution means.

A content distribution method according to a third aspect of the present invention is a content distribution method for distributing content by a computer connected to a network, wherein the computer receives a content delivery request from a user through the network. Searching for the corresponding content from the content compressed and stored in the first compression format based on the payout request received by the computer, and transferring the content in the first compression format searched by the computer to the first compression format. And distributing to the requesting source while converting the data into the compression format of (2).

A content distribution method according to a fourth aspect of the present invention is a content distribution method for distributing content by a computer connected to a network, wherein the computer accepts a content lending request from a user through the network. Searching for the corresponding content from the content compressed and stored in the first compression format based on the lending request received by the computer; and transmitting the content in the first compression format searched by the computer to the first compression format. 2 while adding the information of the lending condition while converting the information to the compression format 2 and distributing the information to the request source.

According to a fifth aspect of the present invention, there is provided a program for causing a computer connected to a network to execute a process, the program causing the computer to receive a content delivery request from a user via the network. Based on the received payout request, the content is compressed and stored in the first compression format, the content is searched, and the content in the first compression format searched by the computer is converted into the second compression format. It is characterized in that it is distributed to the requesting source while doing so.

According to a sixth aspect of the present invention, there is provided a program for causing a computer connected to a network to execute a process, wherein the computer accepts a content lending request from a user via the network. Based on the requested lending request, the corresponding content is retrieved from the content compressed and stored in the first compression format, and the retrieved content in the first compression format is converted into the second compression format while the rental condition is checked. It is characterized in that information is added and distributed to a request source.

According to the first, third, and fifth aspects, when the computer receives a request for dispensing the content from the user via the network, the computer transmits the first compression request to itself or a content server on the network based on the received request for dispensing. The content is searched from the content compressed and stored in the format, and the hit content in the first compression format is distributed to the request source while being converted into the second compression format, so that one content is stored. A content distribution service via a network can be realized.

According to the second, fourth, and sixth aspects, when a computer accepts a request for renting a content from a user via a network, the computer compresses and accumulates the content in a first compression format based on the accepted rent request. The content in the first compression format that has been hit is converted to the second compression format while the information of the lending condition is added to the content and delivered to the request source.

Here, by setting, for example, a lending period, a lending amount, and the like as the lending condition information, the requester can view the contents only within the lending period or the lending amount. Content rental service can be realized.

According to the present invention, when content (eg, video content) is paid out (downloaded) from a computer on a network, a first compression format, for example, MPEG-format, is used by using a compression format conversion and distribution means (transcoder). By automatically and quickly converting video content such as the MPEG-2 format into a second compression format, such as the MPEG-4 format, and distributing the video content, only one video content in the MPEG-2 format is prepared, and the content is transmitted over the Internet. Services such as paying out or renting video contents in different compression formats.

The compression format conversion and distribution means (transcoder) decodes the bit stream of the conversion source and outputs a reproduced image and side information, and converts the reproduced image and side information obtained by the decoding means. A size conversion unit for converting the converted image into a format suitable for the previous format; and a conversion destination by encoding the converted reproduced image obtained by the size conversion unit using motion vector information included in the converted side information. And encoding means for performing indexing processing by using side information obtained by the decoding means. By reducing the motion vector detection processing in the encoding means, data for moving image encoding can be obtained. Performs format conversion at high speed and at the same time performs indexing processing.

That is, the format of video content of a video coding system using motion compensation prediction (MC) and discrete cosine transform (DCT) is converted at high speed, and the content of compressed video is analyzed at high speed. Indexing (cut detection)
And convert it to structured data.

As a result, it is possible to realize a content distribution service via a network while storing one content. Also, a content lending service using a network can be realized.

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram showing a configuration of a moving image distribution system according to one embodiment of the present invention.
FIG. 2 is a diagram illustrating a configuration of a transcoder of the moving image distribution system of FIG. 1.

As shown in FIG. 1, a moving image distribution system according to this embodiment includes a registration terminal 1 installed at a video content production company, a search / reference terminal 2 installed at a general user's home, and the like. The application server 4 includes an application server 4 connected via a communication network such as the Internet 3 and a database server 5 (hereinafter, referred to as a DB server 5) connected to the application server 4.

The registration terminal 1 is a general personal computer, and is used for transferring video contents in a first compression format, for example, MPEG-2 format, to information browsing software such as a browser 11 or a set Web site. Software is installed.

The search / reference terminal 2 is a general personal computer, and is a software for browsing information such as a browser 21 or a second computer downloaded from a Web site.
Software 22 (hereinafter referred to as MPEG-4) for reproducing video contents in a compression format, for example, MPEG-4 format.
The playback unit 22 is installed. Note that the MPEG-4 playback unit 21 may be configured by hardware.

Computers such as the registration terminal 1 and the search / reference terminal 2 are equipped with a device main body capable of loading and reading a CD-ROM or a floppy (registered trademark) disk (FD).
This is a general computer including an input device and a display device connected to the device main body. The input device is, for example, a keyboard, a mouse, or the like. The display device is, for example, a CRT monitor, an LCD monitor, or the like.

A CPU, a ROM and an R
A control unit including an AM, a hard disk drive (HDD), and a CD-R for reading information from a CD-ROM
An OM drive, an FD drive that reads and writes information from and to the FD, a communication device, and the like are mounted. The ROM stores an initial operation setting program such as BIOS. The communication device is a LAN interface (hereinafter, referred to as LAN I / F) such as a LAN board for performing data communication with a LAN or the like. HDD
Is installed with various software including an operating system (hereinafter referred to as an OS).

The application server 4 includes a registration processing unit 41, an indexing unit 42, a search unit 43, a WWW server function unit 44 for publishing a moving image distribution service site on the World Wide Web (hereinafter referred to as WWW), and a transcoder 60. And so on. The registration processing unit 41 converts the MPEG-2 video content from the registration terminal 1 into a D
It is registered in the MPEG-2 database 51 of the B server 5. The INDEXING unit 42 automatically generates INDEX information (structured data) and registers it in the INDEX database 52 when the MPEG-2 video content is registered in the MPEG-2 database 51. The search processing unit 43 searches the INDEX database 52 according to a search instruction from the search / reference terminal 2.

As shown in FIG. 2, the transcoder 60 is an MPE for decoding the MPEG-2 stream A1.
A G-2 decoder A2, a size conversion unit A3 that converts the frame size of the decoded video data into, for example, 共 に in both the vertical and horizontal directions, and converts the size-converted video data into M
MPEG-4 encoder A4, MP that encodes to PEG-4 format and outputs as MPEG-4 stream A5
It has an indexing unit A6 for detecting cuts using the value of the motion vector contained in the internal information from the EG-2 decoder A2 and a preset table of likelihood ratios. If the size conversion of the video data is unnecessary, the size conversion unit A3 is also unnecessary.

MPE which is an international standard system for video coding
In G-1, MPEG-2 and MPEG-4, the MC + DCT method is adopted as a basic coding method.

Therefore, the MP + DCT decoder MP
As shown in FIG. 3, the EG-2 decoder A2 includes a motion compensation prediction unit (MC) 201, an intra-frame / inter-frame (Intra /
Inter) switching unit 202, frame memory (FM) 20
3. Variable length code decoding unit (VLD) 204, inverse quantization unit (I
Q) 205, an inverse discrete cosine transform (IDCT) 206, an adder 207, and the like.

The compressed bit stream of moving image data is supplied to a variable length code decoding unit 204 via a line L21, and a discrete cosine transform coefficient and side information are decoded. The discrete cosine transform coefficient is supplied to the inverse quantization unit 205 and is inversely quantized.
To reproduce the image signal.

Here, when the MB is in the intra-frame coding mode according to the side information supplied via the line L22, the intra-frame / inter-frame switching unit 202 controls the motion supplied from the motion compensation prediction unit 201. Turn off the compensation prediction signal. Since the signal from the intra-frame / inter-frame switching unit 202 is not supplied to the adding unit 207, the image signal supplied from the inverse discrete cosine transform unit 206 is output as it is via the line L23.

On the other hand, when the MB is in the inter-frame coding mode, the intra-frame / inter-frame switching unit 202 turns on the motion compensation prediction signal supplied from the motion compensation prediction unit 201. In addition section 207, in-frame /
An image signal generated by adding the motion compensation prediction signal supplied from the inter-frame switching unit 202 and the motion compensation prediction error signal supplied from the inverse discrete cosine transform unit 206 is output via a line L23. A part of the reproduced image signal generated in this way is stored in the frame memory 203 and later supplied to the motion compensation prediction unit 201.

An MPEG + which is an encoder of the MC + DCT system
As shown in FIG. 4, the four decoder A4 includes a difference value calculation unit 101, a motion compensation prediction unit (MC) 102, an intra / inter (Intra / Inter) switching unit 103, a frame memory (FM) 104, a motion Vector detector (ME) 10
5. Discrete cosine transform unit (DCT) 106, quantization unit (Q)
107, a variable length coding unit (VLC) 108, an inverse quantization unit (I
Q) 109, an inverse discrete cosine transform (IDCT) 110, and an adder 111. The following processing is performed for each macroblock (MB) of 16 × 16 pixels in the luminance signal.

In the difference value calculation unit 101, a difference between the image signal supplied via the line L11 and the motion compensation prediction signal supplied via the line L12 is calculated, and the difference signal is calculated via the line L13. The signal is supplied to the discrete cosine transform unit 106. In the case of the intra-frame encoding (Inter) mode, the line L12 includes a motion-compensated prediction signal generated by the motion-compensated prediction unit 102 in the intra-frame / inter-frame switching unit 1.
The signal is not supplied in the case of the inter-frame coding (Intra) mode. That is, the line L1
3, the signal of the line L11 is supplied as it is, not the difference signal. Switching between the Intra / Inter modes is determined by the motion vector detection unit 105 and supplied to the intra-frame / inter-frame switching unit 103 via the line 14. The motion-compensated prediction signal generated by the motion-compensated prediction unit 102 is generated from signals of already-encoded frames stored in the frame memory 104 according to the motion vector information detected by the motion vector detection unit 105. .

In the discrete cosine transform unit 106, the line L13
After the signal supplied via
This is supplied to the quantization unit 107. The discrete cosine transform coefficient quantized by the quantization unit 107 is
, And is subjected to variable-length encoding, and the inverse quantization unit 10
9 and inversely quantized. The inversely quantized transform coefficient is supplied to the inverse discrete cosine transform unit 110, and the line L13
Is generated and supplied to the adder 111. The adder 111 reproduces an image signal by adding the signal supplied from the inverse discrete cosine transform unit 110 and the signal supplied via the line L12,
04.

In the variable length coding unit 108, the quantization unit 10
After encoding the discrete cosine transform coefficients quantized in step 7 and side information (not shown) such as motion vector information and mode information, the bit stream is multiplexed to generate a bit stream.
Output via.

From the MPEG-2 format by re-encoding to MP
The transcoding to the EG-4 format will be described.

The MPEG-2 stream is an MPEG-2 stream.
The decoded moving image signal is obtained by being decoded by the decoder A2.

In general, a moving image signal reproduced by the MPEG-2 decoder A2 and a moving image signal encoded by the MPEG-4 encoder A4 have different screen sizes. Required. When obtaining a moving image to be supplied to the MPEG-4 encoder by converting the frame size to 縦 both vertically and horizontally, one of the field images is horizontally converted to １ ／ to reduce the frame size to を. obtain.

The MPEG-4 encoder A4 obtains an MPEG-4 stream by compressing the moving picture signal supplied from the size converter A3 in the MPEG-4 format. If the screen sizes do not differ, the size conversion unit A
3 is unnecessary.

As shown in FIG. 5, the indexing unit A6 includes a moving image data input unit 601, a motion vector extraction unit 602, a log likelihood ratio conversion unit 603, and a threshold processing unit 6
04, which is composed of a difference motion vector-likelihood ratio conversion table 605 and the like, and is cut using the value of the motion vector input from the MPEG-2 decoder A2 and the likelihood ratio of the difference motion vector-likelihood ratio conversion table 605. Is detected.

Here, the reason why a cut is detected using a motion vector is that the distribution of the motion vector has the property of greatly changing depending on the presence or absence of a cut.

For example, in successive frames in the same shot, the motion in the background or the object is continuous, so that the motion vectors of adjacent macro blocks are often similar. However, there is often no motion vector (inter-picture prediction coding is not used) because prediction does not hit between frames sandwiching a cut, and even when prediction is used, it is significantly different from surrounding macroblocks. Different motion vectors are likely to occur. Also,
In a B picture, prediction of a direction including a cut in future and past reference images tends to be difficult to use.

The moving image data input unit 601 takes in moving image data compressed by MPEG. The motion vector extracting unit 602 partially or entirely decodes a moving image and extracts motion vector data. The log likelihood ratio conversion unit 603 performs a process of calculating an evaluation value of the presence / absence of a cut for each frame from the motion vector data extracted from the moving image data using the difference motion vector-likelihood ratio conversion table 605. The difference motion vector is a difference vector from the motion vector of the macroblock in the encoding order. The log likelihood ratio is used as the evaluation value. The log likelihood ratio per frame can be obtained by calculating and adding the logarithm of the likelihood ratio of the difference motion vector for each macroblock in the frame.

Difference motion vector-likelihood ratio conversion table 6
The value of the log likelihood ratio set to 05 needs to be obtained before processing. For this purpose, the number of appearances Nc (Vi) of the differential motion vector Vi when there is a cut and the number of appearances Nn (Vi) of Vi when there is no cut are calculated using moving image data whose cut points are already known. Keep it. At this time, the likelihood ratio of Vi is

[0047]

(Equation 1)

Is calculated. Finally, the threshold processing unit 604 compares the log likelihood ratio per frame output from the log likelihood ratio conversion unit 603 with a preset threshold. If the likelihood ratio that the frame is cut exceeds the threshold value, it outputs that there is a cut in that frame, otherwise it outputs no cut.

Here, the operation of the transcoder 60 will be described with reference to the flowchart of FIG.

The transcoder 60 converts (transcodes) the video format from the MPEG-2 format to the MPEG-4 format, and at the same time, indexes the moving image data, and outputs it as structured data.

Here, the internal information of the MPEG-2 decoder refers to side information (auxiliary information) such as a time stamp of the decoded picture, mode information of each macroblock (MB) and motion vector information.

First, in the transcoder 60, the MPEG
-2 decoder A2 sets the initial value of the time stamp (demandTS) of the frame requested by MPEG-4 encoder A4 (S1). Here, the initial value is “0”.

Next, in the MPEG-2 decoder A2, M
MPEG stored in the PEG-2 database 51
-2 stream A1 is read into a stream buffer (not shown) of the MPEG-2 decoder A2 (S2).

Next, the MPEG-2 decoder A2 determines whether the read stream is the end of the MPEG-2 stream (S3).

Here, for example, in the case of the end (Y in S3), the transcoding process ends.

If it is not the end (N in S3), M
The picture signal and the internal information decoded by the PEG-2 decoder A2 are obtained (S4), and the internal information is supplied to the indexing unit A6.

In the indexing section A6, MPEG-2
When the internal information is input from the decoder A2, motion vector information is extracted from the input internal information and supplied to the motion vector extracting unit 602 to perform indexing processing (cut detection) (S5). In the indexing unit A6, the obtained indexing (cut detection) is performed.
And the corresponding thumbnail are output as structured data A7.

Here, the thumbnail is a reduced display of an image corresponding to the indexing result. With this structured data, the user can use the MPEG-2 stream A
1 and the cut position of the MPEG-4 stream A5 and the contents thereof can be easily confirmed.

On the other hand, in the MPEG-2 decoder A2, S
The time stamp (curTS) of the decoded picture is obtained based on the internal information obtained in the process of step 4 (S7).

Then, the MPEG-2 decoder A2 outputs cu
rTS and demandTS are compared (S8).

If curTS is smaller than demandTS (N in S8), the process returns to S2 and the MPEG-2 decoder A2 repeats the above steps.

When the curTS is greater than the demandTS (S8)
Y), the MPEG-2 decoder A2 includes a size conversion unit A
3 is supplied with a reproduction signal of the picture and internal information.

Next, in the size conversion section A3, the MPE
The decoded picture and the internal information supplied from the G-2 decoder A2 are converted into a form suitable for the MPEG-4 encoder A4 (S9) and supplied to the MPEG-4 encoder A4. The processing of the size conversion unit A3 in S9 will be described later.

Next, in the MPEG-4 encoder A4,
Using the motion vector information supplied from the size conversion unit A3, the size-converted image signal from the size conversion unit A3 is compression-encoded (S10).

Specifically, the motion vector information supplied from the size conversion unit A3 is the MPEG-4 encoder A4
(Signal lines are not shown), and by re-searching around the motion vector, the processing amount of the motion vector detection having the largest processing amount in the encoding processing is significantly reduced. I do.

Thus, the MPEG-4 encoder A4
Outputs the MPEG-4 stream and (S1
1) The time stamp (demandTS) of the next request frame according to the frame skip interval determined by itself is obtained (s12), and the process returns to S2 to repeat the above processing.

That is, in this transcoder 60,
At the same time as converting the video format from the MPEG-2 format to the MPEG-4 format, the moving image data is indexed and the process of outputting as structured data is performed at high speed.

The size conversion processing of the size conversion unit A3 will be described with reference to FIG. As described above, in the MPEG-4 encoder A4, frame skipping is performed. Therefore, as shown in FIG.
Not all outputs (decoded pictures, internal information) of the decoder A2 are supplied, but only those required by the MPEG-4 encoder A4.

Therefore, since the screen size needs to be converted only for the necessary image signal, if the output frame rate of the MPEG-2 decoder A2 is different from the input frame rate of the MPEG-4 encoder A4, the screen size is converted. Processing can be reduced.

Further, as described above, the size conversion unit A
At 3, the internal information (mode information and motion vector information for each MB) of the MPEG-2 decoder A2 supplied via the line A8 is converted into a form suitable for the MPEG-4 encoder A4, and is then transmitted via the line A9. MPEG-4 encoder A4
Supplied to

FIG. 8 shows an example of the association of the macro block addresses before and after the screen size change, because the number of macro blocks changes when the screen size is converted.

In FIG. 8, address (h, v) = (0 to
3, 0 to 2) are the addresses of the macroblocks after the size conversion. As an example, when the correspondence between the macroblock address (H, V) before the size conversion is calculated by the following equation, the correspondence is as shown in the figure. Where (i
(nt) indicates that the decimal part is truncated. H = (int) (7 * h / 4); V = (int) (5 * v / 3);

After associating macroblocks before and after screen size conversion as shown in FIG. 8, a motion vector scaling process according to the frame interval as shown in FIG. 9 is performed.

In FIG. 9, the macroblocks before the screen size conversion corresponding to the macroblocks MB_a, MB_b and MB_c after the screen size conversion are MB_A, MB_B and MB_C. At this time, the motion vector 3 assigned to MB_a, MB_b, MB_c
a, 3b, 3c respectively scale the motion vectors 2a, 2b, 2c obtained by scaling the motion vectors 1a, 1b, 1c of MB_A, MB_B, MB_C according to the frame interval ratio according to the screen size ratio. It is obtained by doing.

Here, when there is no motion vector in MB_A, MB_B, MB_C, it is assumed that there is no motion vector of MB_a, MB_b, MB_c. As mentioned earlier, MPEG-4
The motion vector detection unit 105 of the encoder A4 can execute the motion vector detection with a small processing amount by searching for the vicinity (for example, ± 1 pixel) of the motion vectors 3a, 3b, 3c obtained in this way. Become. 3a, 3b, 3c
If does not exist, several pixels (for example, ± 16 pixels) around the zero vector are searched for.

The operation of the whole moving picture distribution system will be described below. In the case of this moving image distribution system, the registration terminal 1 registers the MPEG-2 format video content in the DB server 5 by the registration processing unit 41 of the application server 4. At the same time, the INDEXING unit 42 automatically generates INDEX (structure information) of the video content and stores the INDEX (structure information) in the INDEX database 52 of the DB server 5.

When searching for video contents from the search / reference terminal 2, the application server 4 is accessed from the search / reference terminal 2 and a search title or the like is entered in a search box or the like displayed on the screen of the browser 21, and the search is performed. When an execution button or the like is operated, the search processing unit 43 causes the INDEX database 52 of the DB
X information is searched, and when the corresponding INDEX information is hit, the search result (IND) is transmitted to the transcoder 60.
EX information).

Then, the transcoder 60 sets the IN
The MPEG-2 video content linked to the DEX information is read from the MPEG-2 database 51 of the DB server 5, converted into the MPEG-4 format at high speed, and paid out (downloaded) to the search / reference terminal 2.

At the search / reference terminal 2, the MPEG-4 playback unit 22 plays back the downloaded MPEG-4 format video content.

As described above, according to the moving image distribution system of the present embodiment, the WWW server function unit 44 for publishing the site for the moving image distribution service to the application server 4 and the DB server in response to a request from the user. 5 and a transcoder 60 that reads out the video content from the DB server 5 and distributes the video content while converting it to the MPEG-4 format at a high speed. As a result, a moving image distribution service can be provided only by registering and storing only the MPEG-2 format video content in the DB server 5, and the video content for distribution is manually converted and registered in advance through personnel. You don't have to. Also,
MPEG-2 video content stored in the DB server 5
It is not necessary to register two types, namely, MPEG-4 and MPEG-4, and the disk capacity of the DB server 5 can be reduced. As a result, it is possible to reduce waste of extra resources, labor and labor required for format conversion, and the like.

On the other hand, the video contents of the MPEG-4 format are inferior in the image quality and the sound quality as compared with those of the MPEG-2 format, and it is unknown whether the video contents are actually subjected to streaming distribution by a pay service.

Therefore, a form (business model) of a moving image distribution service that can be actually realized will be described. In this case, as shown in FIG. 10, the moving image distribution system includes a server computer 70 installed in an application service provider (hereinafter referred to as an ASP), a registration terminal 2 installed in a video production company or a video management company, and the like.
A computer 2 (hereinafter referred to as PC2) as a search / reference terminal installed in a general home is connected to the computer 2 via the Internet.

The registration terminal 2 has a browser 21, MPEG
-4 playback unit 22 and an MPEG-2 viewer 23.

The server computer 70 includes the above-described registration processing section 41, search processing section 43, WWW server function section 4
4. In addition to the MPEG-2 database 51, the INDEX database 52, and the transcoder 60, a billing unit 71,
It comprises a charging DB 72, a sales / rent-out unit 73, and the like.

The billing section 71 performs billing processing when selling or renting video contents in accordance with a contract with the user, and stores the information in the billing DB 72. Billing DB 72
Stores charging information for the sold or rented video content. In the case of a post-pay billing system such as a credit card, the billing unit 71
It accesses the host computer through the communication network and makes a decision based on the billing information in the billing DB 72. The selling / renting unit 73 notifies the transcoder 60 of the video content to be sold or rented specified by the user, and after the transcoder 60 displays a preview on the PC 2 in the MPEG-4 format, there is an instruction from the user to confirm. In this case, the video content in the MPEG-2 format is read from the MPEG-2 database 51 and distributed (downloaded) to the PC 2. The sales or lending result information is notified to the charging unit 71.

Hereinafter, a moving image distribution service provided by the moving image distribution system will be described with reference to flowcharts shown in FIGS.

In this case, similarly to the above embodiment, the registration terminal 1
By accessing the ASP server computer 70,
MPEG-2 format video content and its video attribute data are registered in advance in the ASP server computer 70 (S701 in FIG. 11), and the moving image is stored (S70).
2).

The server computer 70 publishes a moving image distribution service providing site on the Internet. This moving image distribution service providing site has a menu screen such as a list of video contents to be registered, sold or lent.

Then, the user of the PC 2 accessing the moving image distribution service providing site is prompted to register as a member.

When registering as a member, the user's personal information and the form of charging when the user purchases or rents the video contents, such as payment by credit card or payment by transfer, are registered (S8 in FIG. 12).
01).

After the user has registered as a member, a list of video contents to be sold or rented is searched (S80).
2) Select a desired moving image (video content) (S803), select, for example, a lending period as a moving image lending condition (S804), select a payment method (S805), and click a preview button. Then, the preview request is received by server computer 70 via the Internet. As rental conditions,
In addition, a lending amount, a usage counter, and the like may be set.

In the server computer 70, when the preview request is received, the selling / renting unit 73 notifies the charging unit 71 of the user information included in the preview request.

The charging unit 71 makes an inquiry to the host computer based on the notified user information, checks whether the user is a user who can deliver video contents (checks a negative list), and as a result of this check, If the user can be delivered, the user is returned to the selling / renting unit 73. The negative list is a list of people for whom post-payment is not possible due to card usage.

When a response indicating that distribution is possible is returned, the selling / renting unit 73 notifies the transcoder 60 of information on the video content included in the preview request.

The transcoder 60 reads the corresponding MPEG-2 compressed format video content from the MPEG-2 database 51, decodes it to obtain the original video content, converts the size of the video content, and
Download to user's PC2 while encoding to MPEG-4 compression format (pay out moving image) (S8)
06).

In PC2, the downloaded MPEG
The video content in the compression format of -4 is reproduced by the MPEG-4 reproducing unit 22, and is preview-displayed on the screen of the PC 2.

When the user who sees the preview display desires to purchase or rent and clicks a button such as "confirm purchase" or "confirm rental" on the screen of the browser 21, the selling / renting unit 73 sets the MPEG-2 database. The corresponding MPEG-2 format video content is read out from 51, the information of the lending period is added to the side information, and the information is distributed to the PC 2.

In the PC 2, the downloaded MPEG
-2 format video contents in MPEG-2 viewer 23
(S901 in FIG. 13), the user
High quality and high quality video contents can be purchased or rented and viewed while at home.

Also, since the downloaded video content is in the MPEG-2 format, various additional information (side information) can be added thereto.

For example, in the case of a rental (rent), for example, information of a rental period (expiration date) is added as information of a rental condition, so that when the period is exceeded, reproduction of a moving image is disabled (S902). ), And so on.

In this case, however, the user must access the moving image distribution service providing site again on the PC 2 and extend the lending period to receive an extension key such as a password and extend the viewing period. Can be.

On the other hand, when the distribution of the video contents is completed, the server computer 70
3 notifies the user of the termination of the video content distribution to the charging unit 71.

Receiving the notification, the billing section 71 communicates with a host computer on the communication network to execute billing processing for the user.

As described above, according to the moving image distribution system of this embodiment, the moving image distribution service providing site (ASP server computer 70) including the sales / rental unit 73 and the charging unit 71 is disclosed on the Internet. In response to a request from a user through the Internet, the server computer 70 first converts the video content in the MPEG-2 format into the MPEG-4 format and converts the
Of the MPEG-2 format is delivered to the PC 2 when the user who sees the preview display performs a purchase or rental decision operation, so that the user stays at home, After checking what kind of desired video content is, the video content can be purchased or rented with confidence, and a more effective moving image distribution service can be provided.

The present invention is not limited to the above embodiment. Each configuration (registration processing unit 41, search processing unit 43, WWW server function unit 4
4, MPEG-2 database 51, INDEX database 52, transcoder 60, charging unit 71, charging D
B72, sales / rent-out unit 73, MPEG-4 playback unit 2
2, the MPEG-2 viewer 23, etc.) can be realized by hardware or software. The software may be stored in a computer-readable storage medium such as a floppy disk, or may be transmitted as a single piece of software (program). In this case, the computer reads the software (program) stored in the storage medium,
By downloading and installing from a site (server) on a LAN or the Internet, processing in each embodiment becomes possible.

The storage medium in the present invention includes:
Magnetic disk, floppy disk, hard disk,
Optical disks (CD-ROM, CD-R, DVD, etc.),
As long as a program can be stored and a computer-readable storage medium such as a magneto-optical disk (MO or the like) or a semiconductor memory can be used, the storage format may be any form.

Also, an OS (Operating System) running on the computer based on the instructions of the program installed in the computer from the storage medium.
Alternatively, MW (middleware) such as database management software and network software may execute a part of each process for realizing the present embodiment.

Further, the software (program) according to the present invention is not limited to one stored in a storage medium independent of a computer, but also includes one distributed via a transmission medium such as a LAN or the Internet.

Further, the storage medium in the present invention is not limited to a medium independent of a computer, but also includes a storage medium in which a program transmitted via a LAN or the Internet is downloaded and stored or temporarily stored.

Further, the number of storage media is not limited to one, and the case where the processing in the present embodiment is executed from a plurality of media is also included in the recording medium of the present invention, and any media configuration may be used.

The computer according to the present invention executes each processing in the present embodiment based on a program stored in a storage medium. An apparatus such as a personal computer and a plurality of apparatuses are connected to a network. Any configuration, such as a configured system, may be used.

Further, the computer in the present invention is:
It is not limited to a personal computer, but also includes an arithmetic processing unit, a microcomputer, and the like included in an information processing device, and collectively refers to devices and devices capable of realizing the functions of the present invention by a program.

[0113]

As described above, according to the present invention, when content is paid out (downloaded) from a computer on a network, the compression format conversion and distribution means automatically and automatically converts the content in the first compression format. By converting to the second compression format and delivering at high speed, MPE
By preparing only one content in the G-2 format, it is possible to realize a content delivery service in a different compression format on the Internet. In addition, by converting the content in the first compression format to the second compression format and adding the information of the lending condition and distributing it to the request source, the request source can only view the content within the lending condition. ,
A content lending service using a network can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a moving image distribution system according to one embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a transcoder mounted on an application server of the moving image distribution system.

FIG. 3 is a diagram showing a configuration of an MPEG-2 decoder of the transcoder.

FIG. 4 is a diagram showing a configuration of an MPEG-4 encoder of the transcoder.

FIG. 5 is a diagram showing a configuration of an indexing unit of the transcoder.

FIG. 6 is a flowchart showing the operation of the transcoder.

FIG. 7 is a view for explaining size conversion in the transcoder.

FIG. 8 is a view for explaining scaling of a macroblock address in size conversion.

FIG. 9 is a diagram illustrating scaling of a motion vector in size conversion.

FIG. 10 is a diagram illustrating a configuration example of a moving image distribution system for realizing a moving image distribution service providing site.

11 is an MPE in the moving image distribution system of FIG.
8 is a flowchart illustrating a G-2 moving image registration process.

FIG. 12 is a flowchart showing processing of a server computer in the moving image distribution system of FIG. 10;

FIG. 13 is a flowchart showing processing on the PC side in the moving image distribution system of FIG. 10;

[Explanation of symbols]

REFERENCE SIGNS LIST 1 registration terminal, 2 search / reference terminal (PC), 3 Internet, 4 application server, 5 DB server, 41 registration processing unit, 22 MPEG-4 playback unit,
23: MPEG-2 viewer, 42: INDEXING
Unit, 43: search processing unit, 44: WWW server function unit, 5
1 MPEG-2 database, 52 INDEX database, 60 transcoder, 70 server computer, 71 charging unit, 72 charging DB, 73 sales /
Lending department.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) H04N 5/92 H04N 5/92 H 5C064 5/93 5/93 E 7/08 7/08 Z 7/081 7/137 Z 7/32 F term (reference) 5B082 AA13 GA02 HA05 5C052 AA01 AB03 AB04 AC08 CC11 DD04 5C053 FA05 FA20 FA23 GA11 GB06 GB19 GB37 HA29 JA21 KA04 KA05 LA15 5C059 KK41 LB05 MA04 MA05 MA23 MC11 MC24 SS010701 TA18 TB07 TC03 TC12 TC25 TD05 UA31 UA39 5C063 AA01 AB03 AB07 AC01 AC05 AC10 CA11 CA23 CA36 DA03 DA07 DA13 DB09 5C064 BA07 BB01 BB10 BC04 BC07 BC18 BC23 BC25 BD02 BD04 BD08 BD09

Claims (6)

[Claims] 1. A means for accepting a content payout request from a user via a network, a storage means for storing content compressed in a first compression format, and a corresponding video content from the storage means based on the received payout request. And a compression format conversion and distribution unit that distributes the content searched by the search unit to a request source while converting the content into a second compression format. 2. A means for receiving a content lending request from a user via a network, a storage means for storing content compressed in a first compression format, and a storage means for retrieving the content from the storage means based on the received lending request. A search means for searching, and a compression format conversion and delivery means for converting the content searched by the search means into a second compression format, adding information on a lending condition and delivering the information to a request source. Content distribution system. 3. A content distribution method for distributing content by a computer connected to a network, the method comprising: receiving a content delivery request from a user through the network; and receiving the content delivery request received by the computer. Based on the first
Searching for the corresponding content from the content compressed and stored in the compression format of the above, and distributing the content in the first compression format searched by the computer to the request source while converting the content into the second compression format And a content distribution method. 4. A content distribution method for distributing content by a computer connected to a network, the method comprising: receiving a content lending request from a user through the network; and receiving the lending request received by the computer. Based on the first
Searching for the corresponding content from the content compressed and stored in the compression format of the above, and adding the information of the lending condition while converting the content in the first compression format searched by the computer into the second compression format And distributing the content to a request source. 5. A program for causing a computer connected to a network to execute a process, the program causing the computer to receive a content payout request from a user through the network, and based on the received payout request. The computer is configured to search for the corresponding content from the content compressed and stored in the first compression format, and convert the content in the first compression format searched by the computer to the request source while converting the content into the second compression format. program. 6. A program for causing a computer connected to a network to execute a process, the computer causing the computer to receive a content lending request from a user via the network, and a first program based on the received lending request. To search for the corresponding content from the content compressed and accumulated in the compression format of the first compression format, add the information of the lending condition while converting the searched content in the first compression format to the second compression format, and send it to the request source. Program for distribution.