JP4902326B2 - Video transmission server and control method thereof - Google Patents

Description

  The present invention relates to a moving image transmission server and a control method thereof.

There is a service for distributing a moving image to a portable terminal device such as a cellular phone. However, in a portable terminal device such as a mobile phone, the specs of a video that can be played back vary depending on the model. For this reason, it is necessary to be able to play regardless of the specifications. For this purpose, the compressed moving image data is decompressed and recompressed according to the load of the network (Patent Document 1). The moving image data is converted into a plurality of moving image data having different bit rates, and the network specifications. Content that selects and distributes video data according to the available bandwidth (Patent Document 2), stores content compressed in the first compression format, and compresses it in the second compression format in response to a request from the user. (Patent Document 3), and the like (Patent Document 4) that generate moving image data for distribution according to the model of the mobile phone.
Japanese Patent Laid-Open No. 9-298749 JP-A-11-341488 JP 2002-232860 JP 2004-222124 A

  However, it is not considered to efficiently generate moving image data for transmission to be transmitted to a mobile phone.

  An object of the present invention is to efficiently generate moving image data for transmission.

  The moving image transmission server according to the first invention is detected by a size detecting means for detecting a maximum size among the sizes of reproduced images of moving images in a plurality of portable terminal devices, the size detecting means. The data amount of the original image data is adjusted so that the original moving image data representing the moving image having a size larger than the size of the reproduced image becomes the size of the reproduced image having the size detected by the size detecting means. Intermediate moving image data generating means for generating intermediate moving image data, and the size of the reproduced image of the intermediate moving image represented by the intermediate moving image data generated by the intermediate moving image data generating means is determined by each of the plurality of portable terminal devices. The intermediate moving image data generated by the intermediate moving image data generating means is adjusted so that the size of the reproduced image of the moving image is transmitted. The transmission moving image data generating means for generating moving image data, and the transmission moving image data generated by the transmission moving image data generation means, the size of the reproduction image in the transmission moving image represented by the respective transmission moving image data, and It is characterized by comprising moving image data transmitting means for transmission for transmitting to the portable terminal device for reproducing a moving image of a reproduced image having the same size.

  The first invention also provides a control method suitable for the moving image transmission server. That is, in this method, the size detecting means detects the maximum size of the reproduced images of the respective moving pictures in the plurality of portable terminal devices, and the intermediate moving picture data generating means detects the size. The original image data so that the original moving image data representing the moving image having a size larger than the size detected by the means becomes the size of the reproduced image having the size detected by the size detecting means. The intermediate moving image data is generated by adjusting the amount of data, and the transmission moving image generating means has a reproduction image size of the intermediate moving image represented by the intermediate moving image data generated by the intermediate moving image data generating means. Data amount of the intermediate moving image data generated by the intermediate moving image data generating means so as to be the size of the reproduced image of each moving image in the portable terminal device The moving image data for transmission is adjusted to generate the moving image data for transmission, and the moving image data for transmission transmits the moving image data for transmission generated by the moving image data for transmission data to be represented by the moving image data for transmission. Is transmitted to the portable terminal device that reproduces the moving image of the reproduced image having the same size as the reproduced image.

  According to the first invention, the maximum size among the sizes of the respective reproduced images in the plurality of portable terminal devices is detected. Intermediate moving image data is generated from the original moving image data so that the original moving image data has a reproduced image having the maximum size detected. Transmission moving image data to be transmitted to the respective portable terminal devices is generated from the generated intermediate moving image data. Rather than generating multiple video data for transmission directly from the original video data, intermediate video data is generated once, and video data for transmission is generated from the generated intermediate video data. it can. Video data for transmission can be generated efficiently.

  According to a second aspect of the present invention, there is provided a moving image transmission server for representing a frame rate of each moving image of the plurality of portable terminal devices, which represents the number of frames of a reproduced image per unit time when the moving images are reproduced by the plurality of portable terminal devices. Of these, the maximum frame rate detecting means for detecting the frame rate with the maximum number of frames of reproduced images per unit time, and the first intermediate moving image data having the maximum frame rate detected by the maximum frame rate detecting means. First intermediate moving image data generating means for generating original moving image data having a frame rate that is a natural number multiple of 2 or more of the maximum frame rate, out of the frame rates of moving images in the plurality of portable terminal devices The second intermediate video data having a frame rate excluding the maximum frame rate is converted into the first intermediate video data. Determining means for determining whether or not the reproduction image of the first intermediate moving image represented by the first intermediate moving image data generated by the generating means can be generated by periodically thinning out the second intermediate In response to the determination that the moving image data cannot be generated, the second intermediate moving image data generating unit generates the second intermediate moving image data from the original moving image data, and the first intermediate moving image data generating unit generates the second intermediate moving image data from the original moving image data. Using the first intermediate moving image data and the second intermediate moving image data generated by the second intermediate moving image data generating means, the transmitting moving image data having the frame rate of the plurality of portable terminal devices is generated. The transmission moving image data generating means, and the transmission moving image data generated by the transmitting moving image data generating means, respectively. Characterized in that it comprises a transmission video data transmission means for transmitting to the portable terminal apparatus for reproducing video of the same frame rate as the frame rate in transmitting video, represented by the transmission video data of.

  The second invention also provides a control method suitable for the moving image transmission server. That is, in this method, the maximum frame rate detection means represents the number of frames of the reproduced image per unit time when the moving image is reproduced on the plurality of portable terminal devices. Among the frame rates, the frame rate having the maximum number of frames of reproduced images per unit time is detected, and the first intermediate moving image data generating means detects the maximum frame rate detected by the maximum frame rate detecting means. Is generated from original moving image data having a frame rate that is a natural number multiple of 2 or more of the maximum frame rate, and the determination means is a frame of moving images in the plurality of portable terminal devices. The second intermediate video data having a frame rate excluding the maximum frame rate among the rates is converted into the first intermediate video data. Determining whether the reproduction image of the first intermediate moving image represented by the first intermediate moving image data generated by the data generation means can be generated by periodic thinning, and the second intermediate moving image data generating means, When the determining means determines that the second intermediate moving image data cannot be generated, the second intermediate moving image data is generated from the original moving image data, and the transmission moving image data generating means Using the first intermediate moving image data generated by the intermediate moving image data generating means and the second intermediate moving image data generated by the second intermediate moving image data generating means. Transmission video data having a rate is generated, and each of the transmission video data generated by the transmission video data transmission unit is generated by the transmission video data generation unit. The chromatography data, and transmits to the portable terminal apparatus for reproducing video of the same frame rate as the frame rate in transmitting moving image represented by each of the transmitting video data.

  According to the second invention, the maximum frame rate of moving images in a plurality of portable terminal devices is detected. First intermediate moving image data having the detected maximum frame rate is generated from the original moving image data. Of the plurality of portable terminal devices that reproduce a moving image having a frame rate excluding the maximum frame rate, the reproduced image of the first intermediate moving image represented by the first intermediate moving image data is periodically (1 Alternatively, it is determined whether or not the second intermediate moving image data can be generated from the first intermediate moving image data by thinning out periodically at a plurality of frames. If it cannot be generated, second intermediate moving image data is generated from the original moving image data. Transmission moving image data is generated from the generated first intermediate moving image data or second intermediate moving image data, and transmitted to the portable terminal device. Also in the second aspect of the invention, the first intermediate moving image data and the second intermediate moving image data are generated without generating the moving image data for transmission directly from the original moving image data. Since the moving image data for transmission is generated from the intermediate moving image data, the moving image data for transmission can be generated efficiently.

  FIG. 1 shows an outline of a moving image distribution system according to the present invention.

  The moving image distribution system includes a moving image distribution (moving image transmission) server 10 and a large number of mobile phones 1 to n. The moving image distribution server 10 and the large number of mobile phones 1 to n can communicate with each other via a network.

  The moving image distribution server 10 stores a large amount of moving image data to be distributed (transmitted) to a large number of mobile phones 1 to n. In response to requests from the mobile phones 1 to n, desired moving image data is transmitted from the moving image distribution server 10 to the requested mobile phone. The mobile phones 1 to n have various specifications. For example, the size of the playback image of one frame constituting the moving image, the frame rate representing the number of playback images per unit time, and the like depend on the mobile phones 1 to n. Among the mobile phones 1 to n, it is necessary to generate moving image data that can be reproduced on the mobile phone of the transmission destination in the moving image distribution server 10 and transmit it to the mobile phone of the transmission destination. In particular, in this embodiment, instead of generating n pieces of moving image data corresponding to each of the mobile phones 1 to n from the original moving image data in order to generate moving image data for transmission, the size of the reproduced image of the original moving image data is increased. Intermediate moving image data smaller than the frame rate and the frame rate is generated, and moving image data for transmission corresponding to each of the mobile phones 1 to n is generated from the intermediate moving image data. The moving image data for transmission can be generated more efficiently than the generation of moving image data for transmission directly from the original moving image data.

  FIG. 2 is a block diagram showing an electrical configuration of the moving image distribution server 10.

  The overall operation of the moving image distribution server 10 is controlled by the CPU 16. The moving image distribution server 10 also includes a main memory 18 for storing operation programs and other data, and a memory control circuit 17 for accessing the main memory 18.

  The moving image distribution server 10 includes a distribution moving image database 15 that stores moving image data for distribution. As described above, the distribution moving image database 15 also stores intermediate moving image data and moving image data for transmission corresponding to the mobile phone. In addition, the moving image distribution server 10 carries distribution information such as the size and frame rate of the reproduced image when the moving image is reproduced on the mobile phones 1 to n as the transmission destination of the moving image data for transmission as described above. A terminal specification database 10 stored for each telephone is also included. The distribution information stored in the terminal specification database 10 is read by the terminal specification acquisition circuit 19.

  The original moving image data stored in the distribution moving image database 15 is read by the content acquisition circuit 11, and the read original moving image data is analyzed by the content analysis circuit 12. By this analysis, the size, frame rate, etc. of the reproduced image of the original moving image represented by the original moving image data can be known. As described above, the intermediate moving image data is generated, and the intermediate moving image format determining circuit 14 determines the format of the intermediate moving image data (reproduced image size, frame rate, etc.).

  Furthermore, generation of intermediate moving image data from the original moving image data and generation of moving image data for transmission from the intermediate moving image data are performed in the moving image conversion circuit 21. The moving image data for transmission is transmitted to the corresponding mobile phone by the content distribution circuit 22. Information on the destination mobile phone is acquired by the distribution information acquisition circuit 13.

  Although the above circuit is configured by hardware, it may be configured by software.

  FIG. 3 is an example of distribution information stored in the terminal specification database 20.

  The terminal specification database 20 stores the size and frame rate of the reproduced image for each model name of the mobile phone. Although the size and frame rate of the reproduced image are stored corresponding to the models of the mobile phones 1 to 26, it is needless to say that the number is not limited to 26 types.

  The size of the reproduced image is represented by the number of pixels in the horizontal direction × the number of pixels in the vertical direction. In the system according to this embodiment, a moving image of a reproduced image having an aspect ratio (vertical to horizontal) of approximately 3 to 4 is used. The size of the reproduced image includes 320 pixels × 240 pixels, 240 pixels × 180 pixels, 176 pixels × 144 pixels, and 128 pixels × 96 pixels. There are 15 fps (frames per second), 10 fps, and 5 fps for the frame rate.

  FIG. 4 shows the relationship between the original moving image data and the moving image data for transmission.

  As described above, the original moving image data D0 is stored in the moving image distribution server 10. In this embodiment, as described above, the transmission video data D11 to D1n that can be reproduced by the mobile phones 1 to n are not generated from the original video data D0, but the intermediate video data D1 from the original video data D0. Is generated. Transmission moving image data D11 to D1n are generated from the generated intermediate moving image data D1.

  The moving image data D11 to D1n for transmission can be efficiently generated because they are generated not from the original moving image data D0 but from the intermediate moving image data D1. When generating video data for transmission that represents a video for transmission that has a small playback image size and a low frame rate (a small number of playback image frames per unit time), the source video The generation time is shorter when the size and the frame rate of the reproduction image are closer to the reproduction image size and the frame rate of the transmission moving image represented by the transmission moving image data. In this embodiment, there is a size between the size of the reproduction image of the original moving image and the size of the reproduction image of the transmission movie, and between the frame rate of the original movie and the frame rate of the transmission movie. An intermediate moving image having a frame rate is generated, and a moving image for transmission is generated using the intermediate moving image, thereby efficiently generating a moving image for transmission.

  For example, the size of the reproduced image of the original moving image data D0 is 640 pixels × 480 pixels, the frame rate is 30 fps, the size of the reproduced image of the intermediate moving image data D1 is 320 pixels × 240 pixels, Assume that the rate is 15 fps. Since the data amount of the original moving image data D0 is proportional to 640 pixels × 480 pixels × 30 fps, and the data amount of the intermediate moving image data D1 is proportional to 320 pixels × 240 pixels × 15 fps, if the time for generating the intermediate moving image data D1 is ignored In the case of generating the moving image data D11 to D1n from the intermediate moving image data D1, the transmission moving image data D11 to D8 are generated in 1/8 time compared to the case of generating the moving image data D11 to D1n from the original moving image data D0. D1n can be generated (320 pixels × 240 pixels × 15 fps / 640 pixels × 480 pixels × 30 fps = 1/8).

  The original video data represents a video of a playback image having a size greater than or equal to the maximum size of the playback images of each video on a plurality of mobile phones at the transmission destination, and a plurality of transmission destinations. It has a frame rate that is a natural number multiple of 2 or more of the maximum frame rate among the frame rates of moving pictures on mobile phones.

  FIG. 5 is a flowchart showing a processing procedure of the moving image distribution server 10.

  As described above, the original moving image data is acquired from the distribution moving image database 15 by the content acquisition circuit 11 (step 31). The acquired original moving image data is analyzed by the content analysis circuit 12, and original moving image information (size of reproduced image of original moving image, frame rate) is acquired (step 32).

Subsequently, distribution information indicating the destination mobile phone is acquired by the distribution information acquisition circuit 13 (step 33). For example, the transmission destination mobile phone is input by the operator of the video distribution server 10 and acquired by the distribution information acquisition circuit 13. Based on the distribution information, the terminal specification of the destination mobile phone is acquired from the terminal specification database 20 by the terminal specification acquisition circuit 19 (step 34).

  An intermediate moving image format is determined from the acquired original moving image information, specification information, etc., and an intermediate moving image is generated (steps 35 and 36). Details of the intermediate moving image format determination process will be described later. Transmission video data for each mobile phone is generated using the generated intermediate video and stored in the distribution video database 15 (step 37).

  FIG. 6 is a flowchart showing a processing procedure (intermediate moving image format determination processing procedure) for determining the size of the reproduced image of the intermediate moving image (part of the processing of step 35 in FIG. 5).

  The size of the playback image of the intermediate video is equal to or smaller than the size of the playback image of the original video, and the largest playback video playback image corresponding to the mobile phone to be generated among the mobile phones 1 to n. It becomes more than the size of the image. For example, the size of the reproduced image of the mobile phones 1 to 26 shown in FIG. 3 is the largest of the reproduced image of 320 pixels × 240 pixels, so let's generate a moving image for transmission for these mobile phones 1 to 26. In this case, the size of the reproduced image of the intermediate moving image is 320 pixels × 240 pixels.

  First, an initial value 0 of the size of the intermediate moving image is set (step 41). Subsequently, the size of the playback image of each mobile phone at the delivery destination is acquired (step 42).

  The size of the reproduced image of the intermediate moving image is compared with the size of the reproduced image of the mobile phone to be transmitted (step 43). If the size of the intermediate video playback image is smaller than the size of the mobile phone playback image (YES in step 43), the size of the intermediate video playback image is larger than the size of the intermediate video playback image. The size of the intermediate moving image is updated so as to be the size of the determined playback image of the mobile phone (step 44). Steps until the comparison of the size of the playback image of the intermediate video and the update processing of the size of the playback image of the intermediate video are completed with respect to the size of the playback image of the last mobile phone of the mobile phone for which transmission video data is to be generated The processes 42 to 44 are repeated (step 45).

  In this way, a size larger than the size of the playback image of all mobile phones that are to generate the moving image data for transmission is determined as the size of the playback image of the intermediate video.

  FIG. 7 is a flowchart showing a processing procedure for determining the frame rate of the intermediate moving image (intermediate moving image format determination processing procedure) (part of the processing of step 35 in FIG. 5).

  The frame rate of the intermediate video is less than or equal to the frame rate of the original video (the number of frames of playback images per unit time is less than or equal to the original video), and for transmission compatible with mobile phones that are trying to generate video data for transmission More than the frame rate of moving images (the number of frames of reproduced images per unit time is more than moving images for transmission). For example, since the maximum frame rate of the cellular phones 1 to 26 shown in FIG. 3 is 15 fps, the intermediate moving image (first intermediate moving image) has a frame rate of 15 fps or more. In particular, in this embodiment, when it is not possible to generate a moving image for transmission by periodically thinning out the playback images constituting the generated intermediate moving image, an intermediate moving image that can be generated by periodically thinning out the generated moving image is also included. Generated. For example, a 10fps transmission movie cannot be generated even if the playback image of an intermediate movie having a frame rate of 15fps is periodically thinned out. Therefore, an intermediate moving image (first intermediate moving image) that can generate a moving image for transmission of 10 fps is also generated.

  First, the frame rates of all mobile phones at the transmission destination are acquired (step 51). The acquired frame rates are sorted in descending order (step 52), and the maximum frame rate (for example, 15 fps) is added as the frame rate of the intermediate moving image (first intermediate moving image) (step 53).

  Subsequently, the next highest frame rate (for example, 10 fps) is acquired (step 54). It is determined whether or not the acquired moving image having the next largest frame rate can be generated by periodic thinning out from the intermediate moving image having the maximum frame rate (step 55). If it cannot be generated, the next highest frame rate is added as the frame rate of the intermediate moving image (second intermediate moving image) (step 56). If it can be generated, step 56 is skipped. The processing of steps 54 to 56 is repeated until the confirmation of whether or not to add the frame rate of all mobile phones for which the moving image data for transmission is to be added to the frame rate of the intermediate moving image is completed (step 57).

An outline of a moving image distribution system according to this embodiment is shown. It is a block diagram which shows the electric constitution of the server for moving image delivery. The relationship between the mobile phone, the size of the reproduced image, and the frame rate is shown. It shows how the moving image data for transmission is generated from the intermediate moving image data. It is a flowchart which shows the process sequence of the moving image delivery server. It is a flowchart which shows an intermediate | middle moving image format determination processing procedure. It is a flowchart which shows an intermediate | middle moving image format determination processing procedure.

Explanation of symbols

1-n mobile phone
10 Video distribution server
14 Intermediate video format decision circuit
21 Movie conversion circuit
22 Content distribution circuit

Claims (4)

A size detecting means for detecting a maximum size among the sizes of reproduced images of the respective moving images in a plurality of portable terminal devices;
The original moving image data representing a moving image having a size larger than the size detected by the size detecting means is set to the size of the reproduced image having the size detected by the size detecting means. Intermediate moving image data generating means for adjusting the data amount of the original image data to generate intermediate moving image data;
The intermediate moving image so that the size of the reproduced image of the intermediate moving image represented by the intermediate moving image data generated by the intermediate moving image data generating means becomes the size of the reproduced image of each moving image in the plurality of portable terminal devices. The moving image data generating means for generating the moving image data for transmission by adjusting the data amount of the intermediate moving image data generated by the data generating means, and the moving image data for transmission generated by the transmitting moving image data generating means , Transmitting moving image data transmitting means for transmitting to the portable terminal device for reproducing a moving image of a reproduced image having the same size as the reproduced image in the transmitting moving image represented by the respective transmitting moving image data;
Video transmission server with Reproduction image frames per unit time out of the frame rate of each of the plurality of portable terminal devices representing the number of reproduction image frames per unit time when a plurality of portable terminal devices reproduce the moving image. Maximum frame rate detection means for detecting the maximum frame rate;
First intermediate moving image data having a maximum frame rate detected by the maximum frame rate detecting means is generated from original moving image data having a frame rate that is a natural number multiple of 2 or more of the maximum frame rate. 1 intermediate video data generation means,
Second intermediate moving image data having a frame rate excluding the maximum frame rate among the moving image frame rates in the plurality of portable terminal devices is generated by the first intermediate moving image data generating means. Determining means for determining whether or not the reproduction image of the first intermediate moving image represented by the one intermediate moving image data can be generated by periodically thinning out;
A second intermediate moving image data generating unit configured to generate the second intermediate moving image data from the original moving image data in response to the determination unit determining that the second intermediate moving image data cannot be generated;
The plurality of portable terminal devices using the first intermediate moving image data generated by the first intermediate moving image data generating means and the second intermediate moving image data generated by the second intermediate moving image data generating means The transmission video data generating means for generating the transmission video data having the frame rate and the transmission video data generated by the transmission video data generation means are represented by the respective transmission video data. Transmitting moving image data transmitting means for transmitting to the portable terminal device that reproduces a moving image having the same frame rate as the transmitting moving image;
Video transmission server with A size detecting means for detecting a maximum size among the sizes of the reproduced images of the respective videos in the plurality of portable terminal devices;
The intermediate moving image data generating means generates original moving image data representing a moving image having a size larger than the size detected by the size detecting means, and a reproduced image having a size detected by the size detecting means. The intermediate video data is generated by adjusting the data amount of the original image data so that
The transmission moving image generating means is configured such that the size of the reproduced image of the intermediate moving image represented by the intermediate moving image data generated by the intermediate moving image data generating means is the size of the reproduced image of each moving image in the plurality of portable terminal devices. So that the moving image data for transmission is generated by adjusting the data amount of the intermediate moving image data generated by the intermediate moving image data generating means,
The transmission moving image data transmission means has the same size as the reproduction image of the transmission moving image data generated by the transmission moving image data generation means in the transmission moving image represented by the respective transmission moving image data. Send to the portable terminal that plays the video of the playback image,
Control method of video transmission server. The maximum frame rate detection means represents the number of frames of a reproduced image per unit time when a moving image is reproduced in a plurality of portable terminal devices, among the frame rates of the respective moving images of the plurality of portable terminal devices, Detect the frame rate with the maximum number of frames of playback images per unit time,
The first intermediate moving image data generating means converts the first intermediate moving image data having the maximum frame rate detected by the maximum frame rate detecting means into a frame number that is a natural number multiple of 2 or more of the maximum frame rate. Generate from original video data with rate,
The determining means uses the first intermediate moving picture data generating means to generate second intermediate moving picture data having a frame rate excluding the maximum frame rate among moving picture frame rates in the plurality of portable terminal devices. Determining whether or not it is possible to generate the first intermediate moving image represented by the generated first intermediate moving image data by periodically thinning out the reproduced image;
A second intermediate moving image data generating unit configured to generate the second intermediate moving image data from the original moving image data in response to the determination unit determining that the second intermediate moving image data cannot be generated;
The transmission moving image data generating means uses the first intermediate moving image data generated by the first intermediate moving image data generating means and the second intermediate moving image data generated by the second intermediate moving image data generating means, Generate video data for transmission having the frame rate of the plurality of portable terminal devices,
The transmission moving image data transmission means converts each transmission moving image data generated by the transmission moving image data generation means to the same frame rate as the frame rate in the transmission moving image represented by each transmission moving image data. A method for controlling a moving image transmission server that transmits a moving image to the portable terminal device.

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