JP2017069845A - Bit rate determination device, server device, bit rate determination method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bit rate determination device capable of improving the quality of a specific moving image block while stabilizing a bit rate during distribution of moving image blocks, a server device, a bit rate determination method and a program.SOLUTION: An encode server 1 identifies moving blocks Bn-m corresponding to divided moving images DMn and determines degrees of importance of the identified moving image blocks Bn-m for each of the moving image blocks Bn-m. Based on the determined degrees of importance, the encode server 1 then makes conversion bit rates different from each other for each of the moving images blocks Bn-m corresponding to each of the divided moving images in a part of the divided moving images DMn divided from an entire moving image M and determines the conversion bit rate for each of the moving image blocks Bn-m in such a manner that a total of the conversion bit rates for each moving image block Bn-m corresponding to each of the divided moving images DMn in a part of the divided moving images DMn divided from the entire moving image M becomes equal to or less than an upper limit value.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a technical field such as a system for determining an appropriate bit rate when encoding moving image data.

  Conventionally, as disclosed in Patent Document 1, for example, a plurality of moving images generated by dividing a moving image displaying the entire shooting range into a plurality of display areas and dividing each divided divided moving image by a predetermined time unit A system is known in which blocks are encoded at a predetermined fixed bit rate and distributed to terminals.

Japanese Patent Laying-Open No. 2015-50572

  By the way, when a moving image block encoded at a variable bit rate is distributed through a network, the bit rate (data amount of the moving image block distributed per unit time) at the time of distribution is not stable, so the service quality cannot be guaranteed. For this reason, in the streaming distribution service, a fixed bit rate is adopted to encode the moving image block. However, the quality (image quality) when a moving image block is encoded at a fixed bit rate is inferior to the quality when a moving image block is encoded at a variable bit rate. In particular, the plurality of display areas of the entire moving picture that is the basis of the divided moving pictures include a display area that is easy to compress (an area with little movement) and a display area that is difficult to compress (an area with movement). In the display area where compression is difficult to perform, there is a problem that the quality is significantly reduced. In addition, when the entire moving image includes a display area that is important for the viewer and a display area that is not so, the quality of the important display area cannot be improved more than the quality of the display area that is not so.

  The present invention has been made in view of the above problems and the like, and a bit rate determination device capable of improving the quality of a specific moving image block while stabilizing the bit rate when distributing the moving image block, A server device, a bit rate determination method, and a program are provided.

  In order to solve the above-mentioned problem, the invention according to claim 1 specifies a plurality of video blocks generated by dividing a plurality of divided videos obtained by dividing a video into a plurality of display areas in predetermined time units. And a plurality of video blocks based on the importance determined by the first determination means, first determination means for determining the importance of the video block specified by the specifying means for each video block The video per one corresponding to each of some of the divided videos among the divided videos that have different bit rates when encoding each of at least two of the video blocks Second determining means for determining the bit rate for each moving image block so that the sum of the bit rates of the blocks is a predetermined value or less. And wherein the door.

  According to a second aspect of the present invention, in the bit rate determining device according to the first aspect of the present invention, the bit rate determining device further includes a specifying unit that specifies a part of the divided moving images, and the second determining unit. Is characterized in that the bit rates of the moving image blocks corresponding to each of the divided moving images specified by the specifying means are different from each other.

  According to a third aspect of the present invention, in the bit rate determining device according to the first or second aspect, the first determining unit calculates an information amount for each moving image block, and uses the calculated information amount as the importance level. It is characterized by determining.

  According to a fourth aspect of the present invention, in the bit rate determining device according to the first or second aspect, the first determining unit relatively determines the importance of the moving image block including the position designated by the operator in the moving image. It is characterized by being determined highly.

  According to a fifth aspect of the present invention, in the bit rate determination device according to any one of the first to fourth aspects, the moving image is divided into a plurality of display areas having an equal area. The image processing apparatus further includes generation means for generating a moving image.

  According to a sixth aspect of the present invention, in the bit rate determining device according to any one of the first to fifth aspects, the second determining means includes a part of the divided moving images. A plurality of groups each including the video block corresponding to each of the group, and in each of the generated groups, the bit rate of the plurality of video blocks is proportional to the importance, and The bit rate is determined for each moving image block so that the sum of the bit rates of the plurality of moving image blocks is a predetermined value or less.

  According to a seventh aspect of the present invention, in the bit rate determining device according to the sixth aspect, some of the moving image blocks included in one of the groups are also included in the other one of the groups, and the second The determining unit is configured to relatively compare the bit rate of the part of the moving image blocks determined in one group and the bit rate of the part of the moving image blocks determined in the other group. A small bit rate is finally determined as the bit rate of the part of the moving image blocks.

  According to an eighth aspect of the present invention, in the bit rate determination device according to any one of the first to fifth aspects, the same number of corresponding areas as the divided moving images are provided, and each of the corresponding areas has a predetermined bit rate. Is further provided with an acquisition means for acquiring a plurality of templates having different allocation patterns of the predetermined bit rate to the corresponding areas. The second determination means comprises: The importance of the plurality of video blocks is normalized so that the average value of the importance of the plurality of video blocks becomes a reference bit rate, and each of the normalized importance and the acquisition unit An error from the predetermined bit rate assigned to each corresponding area of the acquired template is calculated for each of the acquired templates. Difference by using the predetermined bit rate allocated to each of said corresponding regions of relatively small the template, and determines the bit rate for each of the video blocks.

  According to a ninth aspect of the present invention, a specifying means for specifying a plurality of moving image blocks generated by dividing a plurality of divided moving images obtained by dividing a moving image into a plurality of display areas by a predetermined time unit, and the specifying means specify First determination means for determining the importance of each moving image block for each moving image block, and a template having the same number of corresponding areas as the divided moving images, each of which is assigned a predetermined bit rate. Obtaining means for obtaining a plurality of the templates having different allocation patterns of the predetermined bit rate to the corresponding areas, and an average value of the importance levels of the plurality of video blocks is a reference Normalization means for normalizing the importance of the plurality of video blocks so that the bit rate becomes, the importance levels normalized by the normalization means, An error from the predetermined bit rate assigned to each corresponding area of the template acquired by the acquisition unit is calculated for each of the acquired templates, and the calculated error is relatively small for each template. And second determination means for determining the bit rate for each moving picture block using the predetermined bit rate assigned to the corresponding area.

  The invention according to claim 10 is a server device that is accessible from a terminal device via a network, and is generated by dividing a plurality of divided moving images obtained by dividing a moving image into a plurality of display areas in predetermined time units. A specifying means for specifying a plurality of moving image blocks; a first determining means for determining the importance of the moving image block specified by the specifying means for each moving image block; and the importance determined by the first determining means. A bit rate for encoding each of at least two of the plurality of moving image blocks among the plurality of moving image blocks, and for each of the divided divided moving images of the divided divided moving images. The bit rate for each video block is set so that the sum of the bit rates of the corresponding video blocks per one or less corresponds to a predetermined value or less. Second determining means for determining a rate; and distribution means for distributing to the terminal device the moving image block requested from the terminal device and encoded at the bit rate determined by the second determining means. And.

  According to an eleventh aspect of the present invention, a specifying unit that specifies a plurality of moving image blocks generated by dividing a plurality of divided moving images obtained by dividing a moving image into a plurality of display areas by a predetermined time unit, and the specifying unit specify First determination means for determining the importance of each moving image block for each moving image block, and a template having the same number of corresponding areas as the divided moving images, each of which is assigned a predetermined bit rate. Obtaining means for obtaining a plurality of the templates having different allocation patterns of the predetermined bit rate to the corresponding areas, and an average value of the importance levels of the plurality of video blocks is a reference Normalization means for normalizing the importance of the plurality of video blocks so as to achieve a bit rate, and the importance levels normalized by the normalization means, An error from the predetermined bit rate assigned to each corresponding region of the template acquired by the acquisition unit is calculated for each of the acquired templates, and the calculated error is relatively small for each template. Second determination means for determining the bit rate for each moving image block using the predetermined bit rate assigned to the corresponding area; and a moving image block requested by the terminal device, wherein the second determination Distribution means for delivering the moving picture block encoded at the bit rate determined by the means to the terminal device.

  The invention according to claim 12 is a bit rate determination method executed by one or more computers, and is generated by dividing a plurality of divided movies obtained by dividing a movie into a plurality of display areas in a predetermined time unit. A specifying step for specifying a plurality of moving image blocks, a first determining step for determining the importance of the moving image block specified by the specifying step for each moving image block, and the importance determined by the first determining step Each of at least two moving image blocks among the plurality of moving image blocks are encoded with different bit rates, and each of the divided divided moving images among the divided divided moving images. The moving image block so that the sum of the bit rates of the moving image blocks corresponding to the Characterized in that it comprises a second determination step of determining the bit rate for each click, a.

  The invention according to claim 13 is a bit rate determination method executed by one or more computers, and is generated by dividing a plurality of divided movies obtained by dividing a movie into a plurality of display areas in a predetermined time unit. A specific step of identifying a plurality of video blocks, a first determination step of determining the importance of the video block identified by the identifying step for each video block, and the same number of corresponding areas as the divided video, An acquisition step of acquiring a template in which a predetermined bit rate is assigned to each of the corresponding areas, and acquiring a plurality of templates having different allocation patterns of the predetermined bit rate to the corresponding areas. And the plurality of moving images so that the average value of the importance levels of the plurality of moving image blocks becomes a reference bit rate. A normalizing step for normalizing the importance of the lock; each of the importance normalized by the normalizing step; and the predetermined bits assigned to the corresponding areas of the template acquired by the acquiring step An error with a rate is calculated for each of the acquired templates, and the predetermined bit rate assigned to each corresponding region of the template with the calculated error being relatively small, is used for each moving image block. And a second determination step for determining a bit rate.

  According to a fourteenth aspect of the present invention, a specifying step for specifying a plurality of moving image blocks generated by dividing a plurality of divided moving images obtained by dividing a moving image into a plurality of display areas by a predetermined time unit, and specifying by the specifying step A first determining step for determining the importance of the moving image block for each moving image block; and at least two of the plurality of moving image blocks based on the importance determined by the first determining step The bit rates for encoding each of the video blocks are different from each other, and the sum of the bit rates of the video blocks corresponding to each of the partial videos of the divided video is divided. A second determining step of determining the bit rate for each moving image block so as to be less than or equal to a predetermined value. Characterized in that to execute the.

  According to a fifteenth aspect of the present invention, a specifying step for specifying a plurality of moving image blocks generated by dividing a plurality of divided moving images obtained by dividing a moving image into a plurality of display areas by a predetermined time unit, and specifying by the specifying step A first determination step for determining the importance of each moving image block for each moving image block, and obtaining a template having the same number of corresponding areas as the divided moving images, each of which is assigned a predetermined bit rate. An acquisition step of acquiring a plurality of templates having different allocation patterns of the predetermined bit rate to each of the corresponding areas, and an average value of importance of the plurality of video blocks is a reference A normalizing step for normalizing the importance of the plurality of video blocks so as to obtain a bit rate, and the normalizing step. An error between each normalized degree of importance and the predetermined bit rate assigned to each corresponding area of the template acquired by the acquisition step is calculated for each of the acquired templates. Causing the computer to execute a second determination step of determining the bit rate for each moving image block using the predetermined bit rate assigned to each of the corresponding areas of the template having a relatively small error. Features.

  According to the first, second, and ninth to fifteenth aspects, it is possible to improve the quality of a specific moving image block while stabilizing the bit rate when distributing the moving image block.

  According to the third aspect of the present invention, the importance of all moving image blocks can be determined quickly and quantitatively.

  According to the invention described in claim 4, it is possible to determine the importance that the user's preference is more reflected.

  According to the fifth aspect of the present invention, it is possible to simplify the display area and to quickly group the display areas.

  According to the sixth and seventh aspects of the present invention, any bit rate pattern can be determined more flexibly in each moving image block.

  According to the eighth aspect of the present invention, the bit rate for encoding each moving picture block can be determined quickly.

It is a figure showing an example of outline composition of distribution system S concerning this embodiment. (A) is a conceptual diagram showing an entire moving image M, a divided moving image DMn, and a moving image block Bn-m, and (B) is an example of a conversion bit rate determined based on the importance of the moving image block Bn-1. FIG. 6 is a flowchart illustrating an example of an encoding process according to the first exemplary embodiment. It is a conceptual diagram which shows an example in case the display area in one group is "2x2". (A) is a conceptual diagram showing an example of the importance of the moving image block Bn-1, and FIG. 5 (B) shows moving image blocks B6-1, B7-1, B10- belonging to the fifth group G5-1. It is a conceptual diagram which shows an example of the conversion bit rate determined based on each importance of 1 and B11-1. 12 is a flowchart illustrating an example of an encoding process according to the second embodiment. It is a figure which shows the example of a template with which the normalized conversion bit rate was allocated to each corresponding area. (A) is a conceptual diagram showing an example of the importance level of the video block Bn-1, and (B) is normalized so that the average value of the importance level of the video block Bn-1 is 0.5 Mbps. It is a conceptual diagram which shows the example of time.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiment described below is an embodiment when the present invention is applied to a distribution system.

[1. Outline of Configuration and Operation of Distribution System S]
First, with reference to FIG. 1, the structure and operation | movement outline | summary of the delivery system S concerning this embodiment are demonstrated. FIG. 1 is a diagram illustrating a schematic configuration example of a distribution system S according to the present embodiment. As shown in FIG. 1, the distribution system S includes an encoding server 1, a distribution server 2, and a client terminal 3. The encoding server 1 is an example of a bit rate determination device according to the present invention. The encoding server 1, the distribution server 2, and the client terminal 3 are connected to the network NW. The network NW is configured by, for example, the Internet.

  The encoding server 1 receives content including data of moving images taken by a video camera (not shown) and audio data collected by a microphone (not shown) in synchronization with the shooting of moving images from an external device. get. For example, a video camera and a microphone are connected to the encoding server 1 via wired or wireless, and moving image data is acquired from the video camera and audio data is acquired from the microphone. In this embodiment, taking a moving image shot by a video camera as an example, a moving image that displays the entire shooting range is referred to as an “overall moving image”. In addition, a moving image created by motion creation software such as CG or animation other than a moving image shot by a video camera may be used as the entire moving image. A moving image obtained by combining moving images shot by each of a plurality of video cameras may be used as the entire moving image.

  The encoding server 1 divides a plurality of divided moving images DMn (n = 1, 2, 3...) Obtained by dividing the entire moving image M into a plurality of display areas by a predetermined time unit T, thereby a plurality of moving image blocks Bn-m. (M = 1,2,3...) Is generated. FIG. 2 is a diagram illustrating an example of a moving image block generated by the encoding server 1. In the example of FIG. 2, the entire moving image M is divided into 4 × 4 divided moving images DMn (in this example, n = 1 to 16), and is divided into time units T on the reproduction time axis t, so that a plurality of moving image blocks is obtained. Bn-m is generated for each divided video DMn. The encoding server 1 encodes the generated moving image block Bn-m at a bit rate determined as described later. The bit rate for encoding the video block Bn-m is hereinafter referred to as “conversion bit rate”. Further, the bit rate for distributing the moving image block Bn-m is hereinafter referred to as “distribution bit rate”. Note that the encoding server 1 may generate a plurality of moving image blocks Bn-m by encoding the divided moving images DMn at the conversion bit rate while dividing the divided moving images DMn by a predetermined time unit T. Here, the conversion bit rate is the data amount (size) of the moving image block encoded per unit time. In other words, the conversion bit rate is a parameter indicating how many bits per unit time to encode. In addition, encoding generally refers to converting (encoding) data into a code in accordance with a predetermined rule, and may further include compressing data using a compression method such as MPEG.

  The distribution server 2 transmits to the client terminal 3 content including the moving image block Bn-m requested from the client terminal 3 and including the moving image block Bn-m encoded by the encoding server 1. The content is transmitted by streaming distribution via the network NW, for example. The client terminal 3 delivers only the video block Bn-m corresponding to the divided video DMn including the display area (at least a part of the display area) displayed in the display range on the display screen in the entire video M according to the user operation. Request to server 2. That is, the moving image block Bn-m corresponding to the divided moving image DMn that does not include the display area displayed on the display screen in the entire moving image M is not requested. The client terminal 3 receives the content transmitted from the distribution server 2, decodes the moving image block Bn-m included in the received content, and reproduces the divided moving image DMn.

[2. Configuration and function of each device]
Next, the configuration of each device included in the distribution system S of the present embodiment will be described with reference to FIG. As shown in FIG. 1, the encoding server 1 includes a control unit 11, a storage unit 12, a communication unit 13, an interface unit 14, and the like. These components are connected to the bus 15. For example, a video camera and a microphone are connected to the interface unit 14. The communication unit 13 is connected to the network NW. The storage unit 12 includes, for example, a hard disk drive and stores an OS (Operating System), an encoding process program (an example of the program of the present invention), and the like. The encoding processing program is a program that causes the control unit 11 as a computer to execute encoding processing and the like. The encoding processing program may be downloaded from a predetermined server, or may be provided by being stored in a recording medium such as a CD or a DVD. In addition, the storage unit 12 stores content including data of the entire moving image M acquired from the external device and audio data.

  The control unit 11 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The control unit 11 executes encoding processing according to the encoding processing program. In this encoding process, the control unit 11 functions as a specifying unit, a specifying unit, a first determining unit, a second determining unit, an acquiring unit, and a normalizing unit of the present invention. Specifically, first, the control unit 11 divides the entire moving image M into a plurality of display areas to generate a plurality of divided moving images DMn. FIG. 2A is a conceptual diagram showing an entire moving image M, a divided moving image DMn, and a moving image block Bn-m. For example, as illustrated in FIG. 2A, the control unit 11 divides the entire moving image M into a plurality of display areas having an equal area, thereby generating a plurality of divided moving images DMn. Then, the control unit 11 divides each of the divided divided moving images DMn by a predetermined time unit T (for example, 10 seconds), thereby generating a plurality of moving image blocks Bn-m for each divided moving image DMn. Note that the control unit 11 may acquire a plurality of moving image blocks Bn-m for each divided moving image DMn generated by a device different from the encoding server 1.

  Further, the control unit 11 specifies the moving image block Bn-m corresponding to each of the divided divided moving images DMn, and determines the importance of the specified moving image block Bn-m for each moving image block Bn-m. Here, the importance of the video block Bn-m is the importance as viewed from a viewer who views a partial area of the entire video, the photographer of the entire video M, or the editor of the entire video M (in other words, the degree of attention Relative degree of interest). For example, the control unit 11 calculates the information amount of the moving image block Bn-m for each moving image block Bn-m, and determines the calculated information amount for each moving image block Bn-m as the importance level of the moving image block Bn-m. The amount of information quantitatively represents the complexity of the data. For example, the amount of information increases as the number of pixel colors constituting the moving image increases. In addition, a moving picture with more movement has a larger amount of information and is attracting attention from viewers and the like. This is because a moving image with more motion has a larger change per unit time of color information (color tone and gradation) of pixels constituting the moving image. A moving picture is harder to compress than a moving picture (in other words, the size of encoded data is less likely to be smaller). In this example, a moving image block Bn-m having a large amount of information is regarded as a moving image block Bn-m having a high degree of importance. As an example of the information amount, there is a data size (file size) obtained by encoding the moving image block Bn-m. In this case, the control unit 11 encodes the moving image block Bn-m with a predetermined parameter (conversion bit rate), and uses the file size as the information amount of the moving image block Bn-m. Thereby, the importance of all the moving image blocks can be determined quickly and quantitatively.

  As another example, the control unit 11 may determine the importance of the moving image block Bn-m including the position designated by the user (operator) in the entire moving image to be relatively high. Here, examples of the user include the above-described viewer (that is, the user of the client terminal 3), a photographer, an editor, and the like. For example, the control unit 11 obtains position information indicating a position (for example, a coordinate position on an image frame of the entire moving image) designated by the user in a state where at least a partial area of the entire moving image M is displayed on the display screen of the terminal. get. Then, the control unit 11 identifies the moving image block Bn-m including the position indicated by the acquired position information, and assigns the importance of the identified moving image block Bn-m to another moving image block Bn-m (a division not including this position). It is determined to be higher than the video block Bn-m) corresponding to the video. Thereby, the said importance in which a user preference was reflected more can be determined. For example, the photographer may determine before shooting and assign an appropriate numerical value to each moving image block, and the control unit 11 may determine each assigned numerical value as the importance of each moving image block.

  In addition, the control unit 11 determines a part of the divided moving images DMn (for example, DM6 and DM10) among the divided moving images DMn (for example, DM1 to DM16) divided from the entire moving image M based on the determined importance. Each of the video blocks Bn-m (for example, B6-1 and B10-1) corresponding to each of the divided video DMn divided from the whole video M with different conversion bit rates when encoding each other One video block Bn-m (for example, B6-1, B7-1, B10-1, and B11-) corresponding to each of some of the divided videos DMn (for example, DM6, DM7, DM10, and DM11). 1) The conversion bit rate is determined for each moving image block Bn-m so that the total conversion bit rate when encoding is equal to or less than the upper limit (an example of a predetermined value). Here, the upper limit value is an allowable value determined according to the network environment such as the bandwidth of the network NW, for example, and is set to about 2 Mbps, for example.

  FIG. 2B is a conceptual diagram illustrating an example of the conversion bit rate determined based on the importance of the moving image block Bn-1. In the example of FIG. 2B, the conversion bit rates of the video blocks B9-1, B10-1, B11-1 and B12-1 having a relatively high importance are increased, and instead, the importance is relative. Video blocks B5-1, B6-1, B7-1, B8-1, B13-1, B14-1, located around the video blocks B9-1, B10-1, B11-1, B12-1 The conversion bit rates of B15-1 and B16-1 are lowered. As a result, the conversion bit rate can be interchanged so that the total bit rate between the adjacent moving image blocks is equal to or less than the upper limit value. That is, a moving image block having a relatively high importance can have a conversion bit rate interchanged from a moving image block having a low importance among adjacent blocks. Then, the control unit 11 encodes the moving image block Bn-m at the determined conversion bit rate. The encoded moving image block Bn-m is stored in the storage unit 12 as a part of the content, instead of the original whole moving image M data or in association with the original whole moving image M data. The

  Next, as shown in FIG. 1, the distribution server 2 includes a control unit 21, a storage unit 22, a communication unit 23, and the like. These components are connected to the bus 24. The communication unit 23 is connected to the network NW. The storage unit 22 includes, for example, a hard disk drive and stores an OS, a content distribution processing program, and the like. The content distribution processing program is a program that causes the control unit 21 to execute content distribution processing and the like. In addition, the storage unit 22 stores, for example, content including the moving image block Bn-m encoded by the encoding server 1 and audio data. The control unit 21 includes a CPU, a ROM, a RAM, and the like. The control unit 21 executes content distribution processing according to the content distribution processing program. In this content distribution process, the control unit 21 transmits the content including the encoded moving image block Bn-m and audio data to the client terminal 3 in response to a request from the client terminal 3 as described above.

  Next, as shown in FIG. 1, the client terminal 3 includes a control unit 31, a storage unit 32, a video RAM 33, a video processing unit 34, an audio processing unit 35, an operation processing unit 36, a communication unit 37, and the like. Is done. These components are connected to the bus 38. A display unit 34 a is connected to the video processing unit 34. A display screen is displayed on the display unit 34a. A speaker 35 a is connected to the sound processing unit 35. An operation unit 36 a is connected to the operation processing unit 36. Examples of the operation unit 36a include a mouse, a keyboard, and a remote controller. A touch panel that serves as both the display unit 34a and the operation unit 36a may be applied. The communication unit 37 is connected to the network NW. The storage unit 32 includes, for example, a hard disk drive and stores an OS, a content reproduction processing program, and the like. The content reproduction processing program is a program that causes the control unit 31 to execute content reproduction processing or the like. The control unit 31 includes a CPU, a ROM, a RAM, and the like. The control unit 31 executes content reproduction processing according to the content reproduction processing program. In this content reproduction process, the control unit 31 specifies a display range (that is, a display range on the display screen) displayed in the entire moving image M in response to a user operation, and corresponds to the divided moving image DMn including the specified display range. The distribution server 2 is requested for a moving image block Bn-m. Thereby, the content including the moving image block Bn-m transmitted from the distribution server 2 is received, and the received content is temporarily held in a buffer memory provided in, for example, a RAM. Then, the control unit 31 decodes the moving image block Bn-m held in the buffer memory, reproduces the divided moving image DMn, and outputs it to the video RAM 33. In accordance with a control signal from the control unit 31, the video processing unit 34 displays a moving image having a display range that fits on the display screen among the divided moving images DMn written in the video RAM 33. When audio data is included in the content held in the buffer memory, the audio processing unit 35 generates an analog audio signal from the audio data according to the control signal from the control unit 31, and generates the generated analog audio signal. Is output to the speaker 35a.

  Note that the display range displayed in the entire moving image M is specified as a shooting range of a virtual camera that operates by a pseudo camerawork operation (an example of a user operation). The specified display range is changed by the pseudo camera work operation, and the moving image block Bn-m is requested to the distribution server 2 following the change. The pseudo camera work operation includes, for example, a pan operation for swinging the virtual camera left and right, a tilt operation for swinging the virtual camera up and down, and a zoom operation for changing the angle of view of the virtual camera. Here, the virtual camera refers to a viewpoint virtually set for a moving image projected on a virtual screen in a two-dimensional plane or a three-dimensional virtual space. The pan and tilt operations are realized by, for example, a mouse drag operation by the user or a flick operation by the user with a finger or a pen. The zoom operation is realized by, for example, a pinch operation in which the user pinches the display screen with a button provided on an operation unit such as a mouse or with two user fingers.

[2. Encoding process by the encoding server 1]
Next, the details of the encoding process by the encoding server 1 will be described separately for the first embodiment and the second embodiment.

Example 1
First, the encoding process in the first embodiment will be described with reference to FIG. FIG. 3 is a flowchart illustrating an example of the encoding process according to the first embodiment. Example 1 generates a plurality of groups including a plurality of video blocks Bn-m displayed on the display screen at the same time when zoomed in by a zoom operation among the video blocks Bn-m corresponding to each of the divided videos DMn described above (that is, In this example, the conversion bit rate of each moving image block Bn-m is determined in each generated group. The plurality of video blocks Bn-m displayed on the display screen at the same time when zoomed in by the zoom operation is an example of one video block corresponding to each of some of the divided videos DMn among all the divided videos DMn. is there.

  The processing shown in FIG. 3 is performed when, for example, data of the entire moving image M to be encoded, which is shot by a video camera, or the entire moving image M to be encoded among the entire moving images M already stored in the encoding server 1 is used. Triggered when there is an M encoding command. As an example of the entire moving image M to be encoded, for example, the entire moving image M corresponding to the content selected as the reproduction target by the user in the client terminal 3 can be cited.

  When the process shown in FIG. 3 is started, the control unit 11 determines each display area (in other words, a divided moving image DMn obtained by dividing the entire moving image M) into which the entire moving image M to be encoded is divided (step S1). In the example of FIG. 2A, the entire moving image M is divided into 4 × 4 display areas, but the number of divisions is arbitrary and is not particularly limited. In addition, before the process of step S1, the control part 11 divides | segments the whole moving image M into several display area, and divides each divided | segmented moving image DMn by predetermined time unit T, for every divided moving image DMn. A plurality of moving image blocks Bn-m may be generated.

  Next, the control unit 11 displays the information on each display area (for example, coordinates in the image frame constituting the entire moving image M) determined in step S1 and the grouping parameters simultaneously on the display screen when zoomed in. The divided video DMn to be designated is designated, and a plurality of groups are generated between the designated divided videos DMn (step S2). The divided moving image DMn specified here is a partial divided moving image DMn among all the divided moving images DMn divided from the entire moving image M. That is, a combination of the divided videos DMn is specified from all the divided videos DMn. The grouping parameters are defined, for example, how to set the display area in one group (for example, 2 × 2, 1 × 3, 2 × 3, 3 × 3, 1 × 2, 2 × 1, etc.). The The display area is determined based on, for example, a display range when a moving image is zoomed in by a zoom function of a client terminal assumed in advance. As shown in FIG. 2 (A), if the entire moving image M is divided into a plurality of display areas having the same area, the display area can be easily taken and grouped quickly. Can be

  FIG. 4 is a conceptual diagram showing an example when the display area in one group is “2 × 2”. In this case, as shown in FIGS. 4A to 4C, groups G1 to G9 are generated. Further, some of the divided moving images DMn belonging to one group also belong to another group. For example, the divided moving image DM2 belongs to groups G1 and G2, as shown in FIGS. 4 (A) and 4 (B). Further, the divided moving image DM6 belongs to the groups G1, G2, G4, and G5 as shown in FIGS. It should be noted that a plurality of video blocks Bn-m are generated for each divided video DMn by dividing the divided video DMn by the time unit T in the processing after step S3 (where m is the start of playback of the whole video M) Equivalent to the order from the position). For this reason, one group Gk (in this example, k = 1 to 9) is further divided into a plurality of groups Gk-m, and a plurality of (four in this example) displayed on the display screen at the same time when zoomed in. The video blocks Bn-m are grouped together. For example, moving picture blocks B1-1, B2-1, B5-1 and B6-1 belong to the group G1-1.

  Next, the control unit 11 substitutes “0” for the encoding start position s (variable) (step S3). The encoding start position s is a temporal position (for example, expressed in seconds) in the reproduction time axis t direction of the entire moving image M, and is a position between the reproduction start position and the reproduction end position of the entire moving image M. The first encoding start position s is, for example, the playback start position of the entire moving image M. Next, the control unit 11 determines whether or not the encoding start position s is smaller than the reproduction end position of the entire moving image M (step S4). That is, it is determined whether or not the encoding start position s has temporally exceeded the playback end position of the entire moving image M. If the control unit 11 determines that the encoding start position s is smaller than the reproduction end position of the entire moving image M (step S4: YES), the control unit 11 advances the process to step S5. On the other hand, when the control unit 11 determines that the encoding start position s is not smaller than the reproduction end position of the entire moving image M (step S4: NO), the process illustrated in FIG.

  In step S5, the control unit 11 determines whether or not the encoding start position s + T (time unit) is larger than the reproduction end position of the entire moving image M. When it is determined that the encoding start position s + T is not larger than the reproduction end position of the entire moving image M (step S5: NO), the control unit 11 substitutes “s + T” for the encoding end position e (variable) (step S6). On the other hand, when the control unit 11 determines that the encoding start position s + T is larger than the reproduction end position of the entire moving image M (step S5: YES), the reproduction end position of the entire moving image M is substituted for the encoding end position e (variable). (Step S7).

  Next, the control unit 11 includes a plurality of moving images generated by dividing each divided moving image DMn within the range [s, e] of the entire moving image M (that is, the range from the encoding start position s to the encoding end position e). The block Bn-m is specified, and the importance of each specified moving image block Bn-m is determined (step S8). For example, as described above, the control unit 11 encodes each specified moving image block Bn-m with a predetermined parameter, and calculates the file size as the information amount of each specified moving image block Bn-m. Alternatively, the control unit 11 sets the importance level of each identified moving image block Bn-m with a default value. And the control part 11 acquires the positional information which shows the position designated by the user as mentioned above from the client terminal 3 which requested the whole moving image M to be encoded, and specifies the moving image block Bn-m including the position. Then, the degree of importance of the identified video block Bn-m is determined to be higher than the default value.

  Next, the control unit 11 sets an upper limit bit rate BR1 (for example, 2 Mbps) as the upper limit value of the conversion bit rate per group (step S9). Next, the control unit 11 assigns “1” to the loop counter i (variable) (step S10). Next, the control unit 11 determines whether or not the loop counter i is equal to or less than the number of groups (step S11). Here, the number of groups is the number of groups Gk-m of the moving image block Bn-m in the range [s, e] of the entire moving image M. In the case of FIG. 4, the number of groups is nine. When it is determined that the loop counter i is equal to or less than the number of groups (step S11: YES), the control unit 11 advances the process to step S12. On the other hand, if the control unit 11 determines that the loop counter i is not less than or equal to the number of groups (step S11: NO), the control unit 11 proceeds to step S17.

  In step S12, the control unit 11 determines that the conversion bit rates of the plurality of video blocks Bn-m belonging to the i-th group Gi-m are proportional to the respective importance levels determined in step S8, and the i-th group The conversion bit rate of the video block Bn-m belonging to the i-th group Gi-m is provisionally determined so that the sum of the conversion bit rates of the plurality of video blocks Bn-m belonging to the group Gi-m becomes the upper limit bit rate BR1. To do.

  FIG. 5A is a conceptual diagram illustrating an example of the importance of the moving image block Bn-1, and FIG. 5B illustrates moving image blocks B6-1, B7-1, and B-5 belonging to the fifth group G5-1. It is a conceptual diagram which shows an example of the conversion bit rate determined based on each importance of B10-1 and B11-1. In FIG. 5B, the importance is normalized so that the total of the conversion bit rates of the four moving image blocks B6-1, B7-1, B10-1, and B11-1 is 2 Mbps which is the upper limit bit rate BR1. Has been.

  Next, the control unit 11 determines whether or not a conversion bit rate has already been assigned to each moving image block Bn-m whose conversion bit rate has been provisionally determined in the most recent step S12 (step S13). When it is determined that the conversion bit rate has already been assigned (step S13: YES), the control unit 11 selects the conversion bit rate temporarily determined in the latest step S12 and the already assigned conversion bit rate. The smaller conversion bit rate is assigned to the moving image block Bn-m (step S14). On the other hand, when it is determined that the conversion bit rate has not already been assigned (step S13: NO), the control unit 11 assigns the conversion bit rate temporarily determined in the latest step S12 to the moving image block Bn-m (step S15). ). When the allocation in step S14 or S15 is performed for all the moving image blocks Bn-m belonging to the i-th group Gi-m (limited to the range of [s, e]), the control unit 11 increments the loop counter i by 1. Then (step S16), the process returns to step S11. Thus, when the processing from step S12 is performed on all the groups Gi-m in the range [s, e], the processing proceeds to step S17.

  In step S17, the control unit 11 determines (final determination) the conversion bit rate finally assigned to each moving image block Bn-m in the range [s, e] as the final conversion bit rate. Note that for some video blocks Bn-m belonging to a plurality of groups Gk-m in the range of [s, e], a relatively small (minimum in this example) conversion bit rate is the above-mentioned part. This is finally determined as the conversion bit rate of the video block Bn-m. That is, the control unit 11 tentatively determined in one group Gk-m by the above process, the conversion bit rate of the part of the moving image blocks Bn-m, and the part of the part that is provisionally determined in the other group. Among the conversion bit rates of the moving image blocks Bn-m, a relatively small (minimum in this example) conversion bit rate is finally determined as the conversion bit rates of the partial moving image blocks Bn-m. Thereby, the conversion bit rate can be interchanged between the adjacent moving image blocks Bn-m, and a more appropriate conversion bit rate can be determined.

  Next, the control unit 11 encodes each moving image block Bn-m in the range [s, e] at each conversion bit rate determined in step S17 (step S18). Each encoded moving image block Bn-m is stored in the storage unit 12 as a part of the content in association with the original whole moving image M data. Next, the control unit 11 assigns the latest encoding end position e to the encoding start position s (step S19), and returns to step S4. Until it is determined in step S4 that the encoding start position s is not smaller than the playback end position of the entire moving image M, the range of [s, e] in the playback time axis t direction of the entire moving image M sequentially moves backward in time series. However, the process after step S5 mentioned above is performed for each [s, e] range. Thus, when all the moving image blocks Bn-m corresponding to each of the divided moving images DMn divided from the entire moving image M are encoded, the control unit 11 ends the process shown in FIG.

  As described above, according to the first embodiment, the encoding server 1 among the video blocks Bn-m corresponding to each divided video DMn, a plurality of video blocks that are simultaneously displayed on the display screen when zoomed in by a zoom operation. Grouped by Bn-m, the conversion bit rate when encoding each video block Bn-m in each grouped group is proportional to the importance, and each video block Bn-m is encoded Since the conversion bit rate of each video block Bn-m is determined for each group so that the total of the conversion bit rate at the time is the upper limit bit rate BR1, what is in each video block Bn-m Even a conversion bit rate pattern can be determined more flexibly. Encoding the video block Bn-m with the conversion bit rate determined in this way improves the quality of each specific video block Bn-m while stabilizing the delivery bit rate of each video block Bn-m be able to. For example, the quality can be improved even when a plurality of display areas of the entire moving image M include a display area that is easy to compress and a display area that is difficult to compress. In addition, when the plurality of display areas of the entire moving image M include a display area that is important for the viewer and a display area that is not so for the viewer, the quality of the important display area can be improved.

(Example 2)
Next, an encoding process according to the second embodiment will be described with reference to FIG. FIG. 6 is a flowchart illustrating an example of the encoding process according to the second embodiment. Example 2 is an example in which the conversion bit rate of each moving image block Bn-m is determined using a plurality of templates created in advance. Here, the template is a table having the same number of corresponding areas as the display areas (divided moving pictures DMn) divided in the entire moving picture M, and a predetermined conversion bit rate is assigned to each corresponding area.

  The process shown in FIG. 6 is started in the same manner as the process shown in FIG. When the process shown in FIG. 6 is started, the control unit 11 determines each display area (in other words, a divided moving image DMn obtained by dividing the entire moving image M) into which the entire moving image M to be encoded is divided (step S21). The process of step S21 is the same as step S1 in the first embodiment described above. Next, the control unit 11 acquires, from the storage unit 12, for example, a plurality of templates that are assigned with a predetermined conversion bit rate to each corresponding area and have different allocation patterns (step S22). Next, the control unit 11 sets the average value of the predetermined conversion bit rates assigned to the corresponding areas for all the templates acquired in step S22 to be the reference conversion bit rate BR2 (for example, 0.5 Mbps). Then, the assigned conversion bit rate is normalized (step S23).

  FIG. 7 is a diagram illustrating a template example in which the normalized conversion bit rate is assigned to each corresponding region. The three templates (Examples 1 to 3) shown in FIGS. 7A to 7C have different conversion bit rate allocation patterns. Although FIG. 7 shows three template examples, any number of templates may be used. Further, the templates shown in FIGS. 7A to 7C each have a predetermined conversion assigned to the corresponding area belonging to the group, regardless of the group to which the corresponding area of “2 × 2” belongs. The total bit rate is created so as to be equal to or less than the upper limit (for example, 2 Mbps).

  Next, the control unit 11 substitutes “0” for the encoding start position s (variable) (step S24). Next, the control unit 11 determines whether or not the encoding start position s is smaller than the reproduction end position of the entire moving image M (step S25). If the control unit 11 determines that the encoding start position s is smaller than the reproduction end position of the entire moving image M (step S25: YES), the control unit 11 advances the process to step S26. On the other hand, when the control unit 11 determines that the encoding start position s is not smaller than the reproduction end position of the entire moving image M (step S25: NO), the process illustrated in FIG.

  In step S26, the control unit 11 determines whether or not the encoding start position s + T is larger than the reproduction end position of the entire moving image M. When it is determined that the encoding start position s + T is not larger than the reproduction end position of the entire moving image M (step S26: NO), the control unit 11 substitutes “s + T” for the encoding end position e (variable) (step S27). On the other hand, when the control unit 11 determines that the encoding start position s + T is larger than the reproduction end position of the entire moving image M (step S26: YES), the reproduction end position of the entire moving image M is substituted for the encoding end position e (variable). (Step S28).

  Next, the control unit 11 specifies a plurality of video blocks Bn-m generated by dividing each divided video DMn within the range [s, e] of the entire video M, and specifies each specified video block Bn-m. Is determined (step S29). Next, the control unit 11 uses the conversion bit rate BM2 (for example, 0.5 Mbps) as an average of the importance values of the moving image blocks Bn-m specified in the range [s, e] of the entire moving image M. The importance of each moving image block Bn-m specified in the range [s, e] of the entire moving image M is normalized (step S30).

  FIG. 8A is a conceptual diagram showing an example of the importance level of the moving image block Bn-1, and FIG. 8B shows that the average value of the importance level of the moving image block Bn-1 is 0.5 Mbps. It is a conceptual diagram which shows an example when normalized.

Next, the control unit 11 determines each importance degree (importance degree of each moving image block Bn-m) normalized in step S30 and predetermined conversion bits assigned to each corresponding area of the template normalized in step S23. An error V from the rate is calculated for each template normalized in step S23 (step S31). Here, the error V is calculated by the following equation (1).

  In the above equation (1), the error V is the sum of squares of the difference between the numerical value in the template (predetermined conversion bit rate assigned to the corresponding region) and the normalized importance (that is, the square sum of errors). ) Divided by the number of blocks (the number of identified moving image blocks Bn-m) (mean square error). The error V may be calculated by an expression different from the above expression (1).

  Next, the control unit 11 specifies a template having a relatively small (for example, minimum) error V calculated in Step S31 (Step S32). Next, the control unit 11 determines the predetermined conversion bit rate assigned to each corresponding area of the template specified in step S32 as the conversion bit rate of each moving image block Bn-m in the range [s, e]. (Step S33). That is, the control unit 11 uses the predetermined conversion bit rate assigned to each corresponding area of the template specified in step S32 to set the conversion bit rate of each moving image block Bn-m in the range [s, e]. decide.

  Next, the control unit 11 encodes each moving image block Bn-m in the range [s, e] at the respective conversion bit rate determined in step S33 (step S34). Next, the control unit 11 assigns the latest encoding end position e to the encoding start position s (step S35), and returns to step S25. Then, when all the moving image blocks Bn-m corresponding to the divided moving images DMn divided from the entire moving image M are encoded, the control unit 11 ends the process illustrated in FIG.

  As described above, according to the second embodiment, the encoding server 1 uses the normalized importance of each moving image block Bn-m and the normalized conversion bit rate assigned to each corresponding area of the template. Is calculated for each of a plurality of templates having different allocation patterns, and a conversion bit rate of each moving image block Bn-m is determined using a template having a relatively small calculated error V. The conversion bit rate of each moving image block Bn-m can be quickly determined. Encoding the video block Bn-m with the conversion bit rate determined in this way improves the quality of each specific video block Bn-m while stabilizing the delivery bit rate of each video block Bn-m be able to. For example, the quality can be improved even when a plurality of display areas of the entire moving image M include a display area that is easy to compress and a display area that is difficult to compress. In addition, when the plurality of display areas of the entire moving image M include a display area that is important for the viewer and a display area that is not so for the viewer, the quality of the important display area can be improved.

  In the above embodiment, the encoding server 1 has been described as an example of the bit rate determining apparatus of the present invention. However, when the distribution server 2 has the function of the encoding server 1, the present invention is applied to the distribution server 2. Can be applied. In this case, the distribution server 2 constitutes the server device of the present invention. In this case, the control unit 21 of the distribution server 2 functions as a specifying unit, a specifying unit, a first determining unit, a second determining unit, an acquiring unit, and a normalizing unit of the present invention. That is, the control unit 21 generates a plurality of divided moving images DMn by dividing the entire moving image M corresponding to the content selected as the reproduction target by the user of the client terminal 3 or the selection candidate content into a plurality of display areas. The control unit 21 divides each of the divided moving images DMn by a predetermined time unit T, thereby generating a plurality of moving image blocks Bn-m for each divided moving image DMn. In addition, the control unit 21 specifies the moving image block Bn-m corresponding to each of the divided moving images DMn, and determines the importance of the specified moving image block Bn-m for each moving image block Bn-m. The control unit 21 determines the conversion bit rate for each video block Bn-m based on the importance for each video block Bn-m, and determines the conversion bit determined for each video block Bn-m. Encode each video block Bn-m at the rate. Then, the control unit 21 transmits to the client terminal 3 content including the moving image block Bn-m requested from the client terminal 3 and encoded at the conversion bit rate. More specifically, the control unit 21 executes the process shown in FIG. 3 or the process shown in FIG. 6 instead of the control unit 11.

DESCRIPTION OF SYMBOLS 1 Encoding server 2 Distribution server 3 Client terminal 11 Control part 12 Storage part S Distribution system

Claims (15)

Identifying means for identifying a plurality of video blocks generated by dividing a plurality of divided videos obtained by dividing a video into a plurality of display areas by a predetermined time unit;
First determination means for determining the importance of the moving image block specified by the specifying means for each moving image block;
Based on the importance determined by the first determining means, the bit rates for encoding each of at least two of the plurality of moving image blocks are different from each other, and the divided The bit rate is determined for each moving image block so that the sum of the bit rates of the moving image blocks corresponding to each of the divided moving images of the divided moving images is equal to or less than a predetermined value. A determination means;
A bit rate determining apparatus comprising: Further comprising a designating unit for designating a part of the divided videos.
2. The bit rate determination according to claim 1, wherein the second determining unit makes the bit rates of the moving image blocks per one corresponding to the divided moving images specified by the specifying unit differ from each other. apparatus.   The bit rate determination device according to claim 1, wherein the first determination unit calculates an information amount for each moving image block, and determines the calculated information amount as the importance level.   3. The bit rate determination device according to claim 1, wherein the first determination unit determines the importance of the moving image block including a position designated by an operator in the moving image to be relatively high. 4.   5. The bit according to claim 1, further comprising a generation unit configured to generate the plurality of divided moving images by dividing the moving image into a plurality of display areas having an equal area. Rate determination device.   The second determining means generates a plurality of groups including the video blocks per one corresponding to each of the partial videos in the divided video, and in each of the generated groups The bit rate for each video block so that the bit rates of the plurality of video blocks are proportional to the respective importance levels, and the sum of the bit rates of the plurality of video blocks is equal to or less than a predetermined value. The bit rate determining apparatus according to claim 1, wherein the bit rate determining apparatus determines the bit rate. Some of the video blocks included in one group are also included in another group.
The second determining means includes the bit rate of the part of the moving image blocks determined in one group and the bit rate of the part of the moving image blocks determined in the other group. The bit rate determining apparatus according to claim 6, wherein a relatively small bit rate is finally determined as the bit rate of the part of the moving image blocks. The acquisition unit for acquiring a template having the same number of corresponding areas as the divided moving images, and a predetermined bit rate assigned to each corresponding area, wherein the predetermined bit rate is assigned to each corresponding area. Further comprising acquisition means for acquiring a plurality of templates different from each other,
The second determining unit normalizes the importance of the plurality of moving image blocks so that an average value of the importance of the plurality of moving image blocks becomes a reference bit rate, and each of the normalized importance levels And an error with respect to the predetermined bit rate assigned to each corresponding area of the template acquired by the acquiring means for each of the acquired templates, and the calculated error is relatively small The bit rate determination according to any one of claims 1 to 5, wherein the bit rate is determined for each moving image block using the predetermined bit rate assigned to each of the corresponding areas. apparatus. Identifying means for identifying a plurality of video blocks generated by dividing a plurality of divided videos obtained by dividing a video into a plurality of display areas by a predetermined time unit;
First determination means for determining the importance of the moving image block specified by the specifying means for each moving image block;
The acquisition unit for acquiring a template having the same number of corresponding areas as the divided moving images, and a predetermined bit rate assigned to each corresponding area, wherein the predetermined bit rate is assigned to each corresponding area. Acquiring means for acquiring a plurality of templates different from each other;
Normalization means for normalizing the importance of the plurality of video blocks so that an average value of the importance of the plurality of video blocks becomes a reference bit rate;
An error between each importance degree normalized by the normalization unit and the predetermined bit rate assigned to each corresponding area of the template acquired by the acquisition unit is obtained for each acquired template. Second determining means for calculating and determining the bit rate for each moving image block using the predetermined bit rate assigned to each corresponding region of the template with a relatively small calculated error;
A bit rate determining apparatus comprising: A server device accessible from a terminal device via a network,
Identifying means for identifying a plurality of video blocks generated by dividing a plurality of divided videos obtained by dividing a video into a plurality of display areas by a predetermined time unit;
First determination means for determining the importance of the moving image block specified by the specifying means for each moving image block;
Based on the importance determined by the first determining means, the bit rates for encoding each of at least two of the plurality of moving image blocks are different from each other, and the divided The bit rate is determined for each moving image block so that the sum of the bit rates of the moving image blocks corresponding to each of the divided moving images of the divided moving images is equal to or less than a predetermined value. A determination means;
Distribution means for distributing the moving image block requested from the terminal device, the moving image block encoded at the bit rate determined by the second determining means to the terminal device;
A server device comprising: Identifying means for identifying a plurality of video blocks generated by dividing a plurality of divided videos obtained by dividing a video into a plurality of display areas by a predetermined time unit;
First determination means for determining the importance of the moving image block specified by the specifying means for each moving image block;
The acquisition unit for acquiring a template having the same number of corresponding areas as the divided moving images, and a predetermined bit rate assigned to each corresponding area, wherein the predetermined bit rate is assigned to each corresponding area. Acquiring means for acquiring a plurality of templates different from each other;
Normalization means for normalizing the importance of the plurality of video blocks so that an average value of the importance of the plurality of video blocks becomes a reference bit rate;
An error between each importance degree normalized by the normalization unit and the predetermined bit rate assigned to each corresponding area of the template acquired by the acquisition unit is obtained for each acquired template. Second determining means for calculating and determining the bit rate for each moving image block using the predetermined bit rate assigned to each corresponding region of the template with a relatively small calculated error;
Distribution means for distributing the moving image block requested from the terminal device, the moving image block encoded at the bit rate determined by the second determining means to the terminal device;
A server device comprising: A bit rate determination method executed by one or more computers, comprising:
A specific step of identifying a plurality of video blocks generated by dividing a plurality of divided videos obtained by dividing a video into a plurality of display areas by a predetermined time unit;
A first determination step of determining the importance of the video block specified by the specifying step for each video block;
Based on the importance determined in the first determination step, a bit rate for encoding each of at least two of the plurality of video blocks is made different from each other, and the divided The bit rate is determined for each moving image block so that the sum of the bit rates of the moving image blocks corresponding to each of the divided moving images of the divided moving images is equal to or less than a predetermined value. A decision step;
A bit rate determination method comprising: A bit rate determination method executed by one or more computers, comprising:
A specific step of identifying a plurality of video blocks generated by dividing a plurality of divided videos obtained by dividing a video into a plurality of display areas by a predetermined time unit;
A first determination step of determining the importance of the video block specified by the specifying step for each video block;
The acquisition step of acquiring a template having the same number of corresponding areas as the divided moving image, and a predetermined bit rate assigned to each of the corresponding areas, the allocation pattern of the predetermined bit rate to each of the corresponding areas Obtaining a plurality of the templates different from each other;
A normalizing step of normalizing the importance of the plurality of video blocks so that an average value of the importance of the plurality of video blocks becomes a reference bit rate;
An error between each importance level normalized by the normalization step and the predetermined bit rate assigned to each corresponding area of the template acquired by the acquisition step is calculated for each acquired template. A second determining step of calculating and determining the bit rate for each moving image block using the predetermined bit rate assigned to each corresponding region of the template with a relatively small calculated error;
A bit rate determination method comprising: A specific step of identifying a plurality of video blocks generated by dividing a plurality of divided videos obtained by dividing a video into a plurality of display areas by a predetermined time unit;
A first determination step of determining the importance of the video block specified by the specifying step for each video block;
Based on the importance determined in the first determination step, a bit rate for encoding each of at least two of the plurality of video blocks is made different from each other, and the divided The bit rate is determined for each moving image block so that the sum of the bit rates of the moving image blocks corresponding to each of the divided moving images of the divided moving images is equal to or less than a predetermined value. A decision step;
A program that causes a computer to execute. A specific step of identifying a plurality of video blocks generated by dividing a plurality of divided videos obtained by dividing a video into a plurality of display areas by a predetermined time unit;
A first determination step of determining the importance of the video block specified by the specifying step for each video block;
The acquisition step of acquiring a template having the same number of corresponding areas as the divided moving image, and a predetermined bit rate assigned to each of the corresponding areas, the allocation pattern of the predetermined bit rate to each of the corresponding areas Obtaining a plurality of the templates different from each other;
A normalizing step of normalizing the importance of the plurality of video blocks so that an average value of the importance of the plurality of video blocks becomes a reference bit rate;
An error between each importance level normalized by the normalization step and the predetermined bit rate assigned to each corresponding area of the template acquired by the acquisition step is calculated for each acquired template. A second determining step of calculating and determining the bit rate for each moving image block using the predetermined bit rate assigned to each corresponding region of the template with a relatively small calculated error;
A program that causes a computer to execute.

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