JP4915208B2 - Stream data playback system - Google Patents

Description

  The present invention relates to a system that sequentially transmits time series information from a transmission apparatus to a reception apparatus and reproduces the time series information. In particular, it is a technique for transmitting and reproducing high-quality time-series data via a transmission path having a limited transmission band.

  In a conventional stream data reproduction system, first storage means for storing hierarchically structured stream data, data specifying means for reading hierarchical data satisfying the required quality from the first storage means, and transmitting the read hierarchical data A transmission device comprising a transmission means, a reception means for receiving the transmitted hierarchical data, a second storage means for storing the received hierarchical data, and a hierarchy stored in the second storage means corresponding to the received hierarchical data Receiving device comprising second reading means for reading data, combining means for combining the received hierarchical data with the read hierarchical data, display means for displaying the combined stream data, and reproduction request means for requesting reproduction of a desired quality Device.

  With this configuration, when the stream data stored and played back on the receiving side is played back again, high-quality stream data is limited by transmitting only the difference hierarchical data that has not been stored on the receiving device side yet. Thus, transmission and reproduction can be efficiently performed in the transmission band (for example, Patent Document 1).

JP-A-2005-293158 (Embodiment 4, paragraph numbers [0124] to [0150])

  In the conventional stream data reproduction system, in order to transmit the hierarchical data that satisfies the required quality, when the available transmission band of the transmission path becomes narrow due to external factors such as the communication state and the change in the transmission amount, There has been a problem that playback cannot be started immediately or playback is slowed down during playback.

  The present invention has been made to solve the above problems, and provides a stream data reproduction system that reproduces stream data without delay.

In the stream data reproduction system according to the present invention, first accumulation means for accumulating hierarchy information that is information of each hierarchy obtained by hierarchically encoding time-series stream data, and first reading the hierarchy information from the first accumulation means Reading means, transmitting means for transmitting the hierarchical information read by the first reading means to a transmission line, receiving means for receiving the hierarchical information from the transmission line, and storing the hierarchical information received by the receiving means Second storage means, second reading means for reading out the hierarchical information from the second storage means, combining means for combining the hierarchical information stored in the second storage means, display means for displaying the combined information, and first When the second reproduction is performed after the first reproduction, the transmission path is selected from the hierarchical information not accumulated in the second accumulation means. The hierarchical information with the amount of information that can be transmitted a predetermined time before the reproduction scheduled time using the transmission bandwidth available to select with the delivery control means for requesting said first read means, the said distribution control means first The read request to one reading means is hierarchical information that is synthesized and reproduced after the next second reproduction in the second reproduction .

  Since the present invention determines the hierarchy information to be transmitted from the transmission band immediately before transmitting the hierarchy information, the hierarchy information is transmitted by the scheduled reproduction time even when the available bandwidth of the transmission line changes, so that the reproduction is immediately performed. Can be started, or the playback can be prevented from being slowed down during the playback.

Embodiment 1 FIG.
FIG. 1 is a conceptual diagram showing a block configuration for realizing the stream data reproduction system of the present embodiment. In FIG. 1, first storage means 101 that stores hierarchical information, which is information of each hierarchy obtained by hierarchically encoding time-series stream data information with information detail, firstly reads hierarchical information from the first storage means 101. Reading means 102, transmitting means 103 for transmitting the hierarchical information read by the first reading means 102 to the transmission path 104, receiving means 105 for receiving the hierarchical information from the transmission path 104, and storing the hierarchical information received by the receiving means 105 Second accumulating means 106, second reading means 107 for reading out hierarchical information from the second accumulating means 106, synthesizing means 108 for synthesizing the hierarchical information accumulated in the second accumulating means 106, display means for displaying the synthesized information 110, and a layer that is not stored in the second storage means 106 during the second playback that is played after the first playback that plays the stream first A distribution control unit 109 that selects hierarchical information having an amount of information that can be transmitted up to a predetermined time before the scheduled reproduction time using the available transmission band of the transmission path 104 from the information, and requests the first reading unit 102 Prepare.

  Hereinafter, terms will be described. In general, the stream or stream processing method does not process all data after it is read into the computer storage device, but starts the data processing at the same time as the beginning of the data is read and processes the remaining data while processing the data. Is a processing method for reproducing data so as to flow. Stream data is data transmitted by the stream processing method.

  Furthermore, scalability is a function that varies the spatial resolution or temporal resolution of stream data, and hierarchical coding is a technique for realizing scalability. Hierarchically coded stream data is stream data that is hierarchized so that the resolution and the like can be varied by the above-described hierarchical coding method. Further, the layer information refers to an information unit of each layer of stream-coded stream data. Therefore, when the spatial resolution is varied, only low-resolution layer information can be reproduced with only low-level layer information, and high-level reproduction can be realized by including even high-level layer information.

  Also, stream reproduction refers to reproduction (playback) of stream data by the above stream processing method, and is also referred to as first reproduction here.

  The recording time is the time recorded as stream data, and the recording time is held in the stream data. Specifically, it corresponds to a relative time with the start time being 0 in the case of an edited content such as a shooting time with a camera, a recording time with a transmission device, or a movie. During stream playback, playback is performed at a playback time delayed by a predetermined time from the recording time. The reproduction time is the time when the stream data is reproduced on the display unit 110. Furthermore, the scheduled reproduction time refers to a reproduction time that is inevitably determined when reproduction is started.

  Further, the reproduction after receiving the stream data once or after reproducing the stream is hereinafter referred to as second reproduction. Therefore, in the first reproduction, the lower hierarchy information is transmitted. In the second reproduction performed thereafter, the layer information that has already been transmitted and accumulated and the other layer information that is newly transmitted by the stream processing method are synthesized and reproduced.

  Next, the function and effect of the above configuration will be described. In the conventional system, there is a problem that even if the user explicitly designates the quality and reproduces, it cannot be reproduced immediately or stops during reproduction. In order to solve this problem, the present embodiment adopts the above configuration, so that the portion of the stream data that is repeatedly reproduced is given priority to the hierarchical information of the portion that is repeatedly reproduced as an important portion or a portion that the user wants to see. It is intended to be transmitted to. Specifically, the distribution control means 109 transmits the hierarchical information that has not been stored in the second storage means 106 with the hierarchical information of the recording time to be reproduced during the second playback within the transmission band of the transmission path 104. Request to the first reading means 102. As a result, the second accumulating unit 106 accumulates even hierarchical information in which the hierarchical information of the portion of the stream data where the second reproduction is repeated has higher resolution information. Since this high-level hierarchical information is synthesized and displayed, stream data with high resolution can be reproduced for the portion of the stream data that is repeatedly reproduced.

  Here, the distribution control means 109 determines the hierarchy information to be transmitted within the transmission band of the transmission path 104 among the hierarchy information not yet stored in the second storage means 106. At this time, the distribution control unit 109 selects hierarchical information having an information amount that can be transmitted by a predetermined time before the scheduled reproduction time. Here, the predetermined time is a processing time required for the internal processing.

  In addition, the predetermined time in the present embodiment can be the sum of the time required for combining the hierarchical information in the combining unit 108 and the time required for the display unit 110 to decode and display. By setting the predetermined time in this way, the hierarchical information is reliably combined, decoded, and displayed after transmission, so the configuration of the present embodiment does not cause a problem that cannot be reproduced immediately or a problem that stops during reproduction. effective.

  FIG. 2 is a diagram illustrating a configuration of an apparatus that realizes the stream data reproduction system according to the present embodiment. The present embodiment is an example in which a stream data reproduction system is realized by using information of moving images taken by a camera as time-series stream data. In FIG. 2, a stream data reproduction system includes a camera 201 that captures a moving image, a distribution device 202 that stores and distributes the captured moving image as stream data by wired or wireless connection to the camera 201, and wired stream data. Alternatively, a network 203 that is a transmission path 104 to be distributed wirelessly, a reception device 204 that receives stream data from the network 203 and reproduces a moving image, and a display device 219 that displays the reproduction content are provided. In the drawings, the same reference numerals denote the same or corresponding parts, and this is common throughout the entire specification. Further, the description of the constituent elements appearing in the whole specification is merely an example and is not limited to these descriptions.

  Here, the transmission device 202 includes the first storage unit 101, the first reading unit 102, and the transmission unit 103, and the reception device 204 is combined with the reception unit 105, the second storage unit 106, and the combination. Means 108. The distribution control means 109 described above is provided for each function in the transmission apparatus 202 and the reception apparatus 204, and realizes the distribution control means 109 together. As described above, the distribution control unit 109 can be realized by being distributed to a plurality of devices and the transmission path 104, or the reception apparatus 204 and the transmission apparatus 202 communicate with each other using the transmission path 104 to perform the first reading unit 102. Alternatively, the distribution control means 221 can be configured only in the receiving device 204 so as to request the hierarchical information.

  Such a stream data reproduction system is applied to a video surveillance system for disaster prevention and crime prevention purposes, or a television relay such as news and sports.

  Next, the hardware of each device will be described. FIG. 3 is a diagram illustrating a hardware configuration that implements the transmission device 202 and the reception device 204 according to the present embodiment. In FIG. 3, hardware that implements the transmission device 202 and the reception device 204 is a computer such as a personal computer or an electronic device such as a portable terminal. A central processing unit 303 that performs arithmetic processing based on information in an input unit 301 that inputs information from an input device such as a keyboard, numeric keys, cursor keys, mouse, and joystick, and a storage unit 302 that stores information. A display unit 304 that displays the result as display information such as characters and images on a liquid crystal display, a CRT, and the like, and a communication unit 305 that communicates with the outside by wired or wireless communication to exchange information.

  The hardware of the camera 201 is a camera that captures a moving image, and transmits the moving image to the transmission device 202. 2 is not limited to the configuration having the encoding means in the camera 201, and even if the moving image is transmitted to the transmission apparatus 202 and then encoded in the transmission apparatus 202, the first storage means 101 of the transmission apparatus 202 has a hierarchy. If the encoded stream data is accumulated, this embodiment can be realized.

  Next, it will be described with which hardware the means of each device is realized. The first storage unit 101 of the transmission device 202 is realized in the storage unit 302 and the hierarchical information is stored in the storage unit 302. The first reading unit 102 reads the hierarchical information stored in the storage unit 302, and the transmission unit 103 is realized mainly in the communication unit 304.

  In addition, the reception unit 105 of the reception device 204 is mainly realized in the communication unit 304, and the second storage unit 106 is realized in the storage unit 302, and the hierarchical information is stored in the storage unit 302. The second reading unit 107 reads the hierarchy information stored in the storage unit 302, and the combining unit 108 combines the read layer information with the central processing unit 303. The display unit 110 displays the information combined by the combining unit 108 on the display unit 304. The reproduction request unit 220 is realized in the input unit 301, and the distribution control unit 109 requests the transmission apparatus 202 for layer information based on the layer information stored in the storage unit 302 and the transmission band information of the transmission path 104. The processing is realized in the central processing unit 303. The storage unit 302 stores a program for causing the computer to execute as each unit. Each unit reads this program, and each unit is executed by the central processing unit 303.

  Hereinafter, each device will be described. The camera 201 transmits an image capturing unit 206 including a lens, an image sensor, and the like, an encoding unit 207 that encodes the captured image data into hierarchically structured moving image data, and the encoded moving image data. The camera transmission means 208 is provided. The hierarchically structured moving image data is hierarchically encoded (scalable) stream data and corresponds to the hierarchically structured stream data stored in the first storage unit 101 in FIG.

  The transmission apparatus 202 includes an information receiving unit 209 from a camera that receives moving image data from the camera 201, a first accumulation unit 101 that accumulates the received hierarchical moving image data, and the requested moving image data as a first. A first reading unit 102 that reads from the storage unit 101 and a transmission unit 103 that sequentially transmits the read hierarchical information in accordance with the timing of stream reproduction are provided. Further, the transmission device 202 can be configured to include a distribution control unit 214 having a part of the functions of the distribution control unit 109. For example, the distribution control unit 214 first responds to the stream data reproduction request on the basis of the information on the available transmission band and the hierarchical level stored in the second storage unit 106, in real time without delay in the receiving device 204. The layer information that can be transmitted is determined in accordance with the stream reproduction timing. Next, the distribution control unit 214 requests the first storage unit 101 to read the hierarchical data.

  Hereinafter, “transmission is possible in accordance with the timing of stream playback in real time without delay by the receiving device 204” is referred to as “stream transmission is possible” or “stream delivery is possible”.

  The camera 201 and the transmission device 202 are connected by a broadband network such as a LAN (Local Area Network) that can distribute high-quality moving image data, or a high-speed interface such as USB (Universal Serial Bus).

  The receiving device 204 receives the hierarchy information stored in the receiving means 105 that receives the transmitted hierarchy information, the second accumulation means 106 that accumulates the received hierarchy information, and the second accumulation means 106 that corresponds to the received hierarchy information. A second reading unit 107, a combining unit 108 for combining the hierarchy information read from the second reading unit 107, a display unit 110 for displaying the combined stream data, and a reproduction request unit 220 for requesting reproduction of the stream data are provided. Further, the reception device 204 includes a distribution control unit 221 that performs the above distribution control in cooperation with the distribution control unit 214 of the transmission device 202. For example, the distribution control means 221 first obtains the recording time of the stream data to be reproduced from the information of the reproduction request means 220, and the hierarchy stored in the second accumulation means 106 with the hierarchy information corresponding to the stream data at this recording time. Ask for a level. Next, the distribution control unit 221 transmits to the distribution control unit 214 the recording time of the stream data to be reproduced and the stored hierarchical level information.

  Further, the synthesizing unit 108 can be configured to synthesize the received hierarchy information and the read hierarchy information. Before storing the received hierarchy information in the second storage means 106, the synthesis means 108 combines the received hierarchy information with the hierarchy information read from the second storage means 106, and received it immediately before the synthesis. Hierarchical information can be combined and played back. In other words, the time for storing in the second storage means and the time for reading from the second storage means are not required, and a stream can be generated with less delay. When the received hierarchical information is combined before being stored in the second storage unit 106, the second storage unit 106 stores the received hierarchical information after the combining or in parallel with the combining. By this accumulation, the synthesizing means 108 can be made a synthesis target for reproducing the hierarchical information in the next and subsequent reproductions.

  Also, when the received hierarchy information and the hierarchy information read out from the second storage means 106 are combined, the received hierarchy information is actually stored in the memory, and the combination means 108 reads out the hierarchy information from this memory. It will be. Considering that the memory is also part of the second storage means 106, it can be said that the hierarchical information read from the second reading means 107 is combined. Therefore, in this specification, it is expressed that the hierarchical information read from the second reading unit 107 is combined, including the case where the received hierarchical information and the hierarchical information read from the second storage unit 106 are combined.

  It is assumed that the network 203 does not have a band in which all hierarchical data of high-quality moving image data stored in the transmission device 202 can be stream-distributed by one second reproduction in the reception device 204. In the present embodiment, for example, a network in which the bit rate of high-quality moving image data is 10 M [bps] (bits per second) and the transmission band is only 2 M [bps], or a network having a bandwidth of 100 M [bps]. It is assumed that 10 M [bps] high-quality moving image data is simultaneously delivered at least 10 streams.

  FIG. 4 is a diagram showing a hierarchical structure, taking moving image data as an example of hierarchically structured stream data. FIG. 4A is a conceptual explanatory diagram of stream data that is a moving image. In FIG. 4A, axes X and Y represent the horizontal direction and vertical method of the image, and the depth direction of the axes X and Y represents the time axis T. The image frame 401 of the moving image is arranged along the time axis in time series, and for convenience, the image frame numbers (1 to 8) are displayed on the upper right in order of time series. Here, the image frame 401 corresponds to one still image of a moving image that continuously displays changing still images.

  The hierarchically structured stream data (hierarchically encoded stream data) in the present embodiment is composed of basic data of hierarchy 1 and a plurality of hierarchy data of extension data of hierarchy 2 or higher. Hierarchical data can be reproduced with low quality only by layer 1, and can be reproduced with high quality by sequentially adding and combining layers 2 and above. Here, information representing each hierarchy is referred to as hierarchy information. FIGS. 4B and 4C show examples of spatial hierarchical structuring using the spatial resolution of an image and temporal hierarchical structuring using thinning (temporal resolution) of image frames.

  FIG. 4B shows an example of spatial hierarchical structuring. Each image frame 401 constituting the moving image data is hierarchized into three resolutions, and each hierarchy corresponds to hierarchy information. For example, the layer 1 layer information can reproduce an image having a resolution of 1/4 × 1/4 of the original image. Further, a combination of the hierarchy information of the hierarchy 1 and the hierarchy information of the hierarchy 2 (denoted as “hierarchy 1 + 2”, hereinafter the same notation format) has a resolution of 1/2 × 1/2 of the original image. Can play back images. Further, the hierarchy 1 + 2 + 3 reproduces the current image itself. In FIG. 4B, the data of the hierarchy information corresponding to the hierarchy 1 to 3 is represented by a box 402, and “(image frame number): (hierarchy number)” is written in the box 402. The following figure takes this notation format. A box including this notation format represents hierarchical information data 402 for the hierarchy of image frames.

  FIG. 4C shows an example of temporal hierarchical structure. In this example, a moving image whose number of image frames per unit time (frame rate) is 3N [fps] (frame per second) is divided into three layers of N [fps]. In FIG. 4C, the hierarchy information of the hierarchy 1 is image frames 1, 4,..., The hierarchy information of the hierarchy 2 is image frames 2, 5,. , 6, .... Here, each layer is composed of a plurality of image frames 401, each image frame is represented by a quadrilateral 401, and an image frame number is indicated in the center, and “(image frame number): (layer number)” is indicated on the right shoulder. Has been. The schematic diagram on the right side of FIG. 4C shows the reproduction timing for each layer with the elapsed time on the horizontal axis. Here, a solid quadrilateral 401 indicates that an image frame is reproduced, and a broken quadrilateral 401 indicates that the reproduction display is not changed at that time. When the hierarchy is configured as described above, the hierarchical information of the hierarchy 1 is N [fps], the hierarchy 1 + 2 is 2N [fps], and the hierarchy 1 + 2 + 3 is 3N [fps]. A moving image is played back.

  Image coding having such a hierarchical structure is called scalable image coding, and is also adopted in image coding methods such as MPEG-2 / 4 (Motion Picture Experts Group) and JPEG / JPEG2000 (Joint Photographic Experts Group). ing. In addition to the example of FIG. 4, there are various methods such as spatial hierarchization based on SNR (Signal to Noise Ratio), color components, and positions (for example, attention area and background), and temporal hierarchization such as motion compensation accuracy. . The present invention does not depend on these specific coding schemes and hierarchical structuring schemes, and can be applied to stream data having a hierarchical structure.

  FIG. 5 is a diagram showing the data structure of the hierarchical structured stream data 211 stored in the first storage unit 101. The stream data of this embodiment is composed of stream entity data 530 that is moving image data itself, and stream management data 531 that describes management information such as attributes and location of the entity data. In moving image data, a still image (image frame) that is two-dimensional information is spatially hierarchically structured, and includes a plurality of contents. Here, content is the content of information, and moving image data includes a plurality of contents means that there are a plurality of contents having different contents in moving image data. For example, cameras with different installation positions If there is a moving image, a moving image from one camera can be one content.

  The stream management data 531 includes a content ID (identifier) that is a content identifier, content attribute information, hierarchical structure attribute information, and pointer information to the stream entity data 530. The content attribute information describes information related to the content such as the content title, shooting time, time length, image resolution, and encoding method.

  The hierarchical structure attribute information describes information about the hierarchical structure such as the type of the hierarchical structure, the total number of hierarchies, the hierarchy number, and the average bit rate for each hierarchy. The pointer information to the stream entity data 530 is composed of an address and a data length at which each image frame and each layer information of the image frame are recorded.

  When the information receiving unit 209 from the camera receives the hierarchical structured stream data (moving image data) 211, the first accumulation unit 101 stores the hierarchical structured stream data (moving image data) as stream entity data 530 in a memory or The data is stored in a storage unit (storage device) 302 such as a hard disk. Also, corresponding stream management data 531 is created and updated, and stored in the storage unit (storage device) 302. The first storage unit 101 refers to this stream management data 531 based on information such as a content ID, an image frame, and a layer number given from the distribution control unit 214 (109), and converts the desired layer information into a stream entity. Read from data 530.

The distribution control unit 109 refers to the hierarchical structure attribute information of the stream management data 531 and the data length of the hierarchical information included in the entity pointer information, and determines hierarchical information that can be stream-transmitted without delay in the usable transmission band. For example, the distribution control unit 109 distributes hierarchical information of a hierarchy m or higher (with a transmission bandwidth of W [bps] (bits per second), an average bit rate of the hierarchy n Rn [bps], and lower than the hierarchy m). If the hierarchy information has already been stored in the second storage means 106)
I tier data satisfying the inequality W ≧ Rm +... + Rm + i can be distributed.

  FIG. 6 is a diagram showing the data structure of hierarchically structured stream data stored in the second storage means 106. This data structure is the same as the data structure of the hierarchical stream data 211 stored in the first storage unit 101 of FIG. 5, and the stream entity data 630 stored is stored in the first storage unit 101. This is a part of the stream entity data 530. That is, during reproduction, moving image data that has already been received by the receiving device 204 and stored in the second storage unit 106 and has not yet been deleted is stored in the second storage unit 106. Further, the stream management data 631 includes the content ID, content attribute information, hierarchical structure attribute information of the hierarchical structured stream data (moving image data) 211 stored in the second storage means 106, and the substance to the recorded hierarchical data. Pointer information is described.

  First, the distribution control unit 109 refers to the stream management data 631 and stores the hierarchical structure stream data (moving image data) 211 requested for reproduction in the second storage unit 106 or which layer information is stored. Find out what has been done. Next, the distribution control unit 109 refers to the stream management data 531 and 631 of the first storage unit 101 and the second storage unit 106 to exceed the available transmission band for the requested moving image data. It is determined which hierarchical information of each image frame should be transmitted so that there is no need.

  The available transmission band of the transmission path 104 is, for example, between the distribution control unit 214 and the distribution control unit 221 in the transmission device 202 and the reception device 204 or between management units of a network management device connected to the network. By notifying the arrival time and discard information of the data packet, it is possible to measure the network traffic and determine the transmission band in which stream transmission is possible. The present embodiment does not depend on these specific methods, and can be applied as long as the last available transmission band can be obtained. As a method for measuring the available transmission band, a method of predicting an average transmission band that can be used from the present to the scheduled reproduction time from the past network traffic trend may be used. In this case, there is an effect that more hierarchical information can be reliably transmitted.

  FIGS. 7 to 10 are diagrams for explaining a stream transmission method and a stream reproduction method when the hierarchical structured stream data 211 is repeatedly reproduced a plurality of times. Hereinafter, moving image data will be described as an example of stream data. It should be noted that stream data such as audio data, moving image and audio data, and other multimedia data are stream transmission and stream reproduction methods similar to moving image data.

  FIG. 7 shows an example in which hierarchically structured stream data 211 structured in three layers according to spatial resolution is reproduced twice. Here, it is assumed that the available transmission band can be stream-distributed without delay in only one layer. In the graphs of FIGS. 7A, 7 </ b> C, and 7 </ b> E, the horizontal axis indicates the elapsed time, the vertical axis indicates the transmission band, and the available transmission band BW <b> 1 of the transmission path 104 is indicated by a one-dot chain line. Further, the transmission band of the layer information data corresponding to each layer is represented by a box 402, and “(image frame number): (layer number)” is written in this box 402 (hereinafter, the horizontal axis represents time. , The same as the graph with the band on the vertical axis). 7A and 7B are explanatory diagrams of the first reproduction, that is, the stream reproduction and the first reproduction. At the time of the first reproduction, no corresponding hierarchy information is recorded. Only the data of the hierarchy information of the hierarchy 1 is read and streamed from the first storage unit 101 to the reception apparatus 204 from the transmission apparatus 202 in accordance with the stream reproduction timing on the reception apparatus 204 side. Therefore, as shown in FIG. 7A, only the layer information data 402 of layer 1 is transmitted. Here, an alternate long and short dash line BW1 represents an available transmission band of the transmission path 104 (the same applies to the following drawings). The receiving device 204 side sequentially stores the received layer 1 hierarchy information in the second storage unit 106. Further, the display unit 110 decodes the hierarchy information of the hierarchy 1 and displays the moving image as an image frame 401 having a 1/4 × 1/4 resolution of the original image (see FIG. 7B).

  FIGS. 7C and 7D are explanatory diagrams when the moving image data of the same content is reproduced again. In this case, the second reproduction is performed. As shown in FIG. 7C, the stream data reproduction system is configured to transmit (stream delivery) only the layer information of the difference layer 2 so as not to exceed the available transmission band BW1 of the network 203. . Specifically, first, the receiving device 204 stores the hierarchy information received by the receiving unit 105 in the second storage unit 106. Along with this accumulation, the second reading means 107 reads the hierarchy information of the hierarchy 1 accumulated in the first reproduction from the second accumulation means 106. Next, the synthesizing unit 108 synthesizes the read hierarchy information of the hierarchy 1 and the received hierarchy information of the hierarchy 2. Next, the display means 110 decodes the image frame 401 of 1/2 × 1/2 resolution of the original image and displays a moving image (see FIG. 7D).

  FIGS. 7E and 7F are explanatory diagrams when the moving image of the same content is played back for the third time (second playback of the second time). At this time, the second reproduction is the second time. As shown in FIG. 7E, the stream data reproduction system is configured to transmit (stream delivery) only the difference layer 3 hierarchy information. Specifically, first, the receiving device 204 stores the received hierarchy information in the second storage unit 106. Along with this accumulation, the second reading means 107 reads the hierarchy information of the hierarchy 1 and 2 accumulated in the first and second reproduction (first reproduction and first second reproduction) from the second accumulation means 106. Next, the synthesizing unit 108 synthesizes the read hierarchy information with the received hierarchy information of the hierarchy 3. Next, the display unit 110 decodes the image frame 401 without resolution reduction from the original image and displays a moving image (see FIG. 7F).

  In the above transmission, first, the distribution control means 109 takes into consideration the information amount of this hierarchical information and the available transmission band BW1 from the hierarchical information not stored in the second storage means 106. Hierarchical information that can be transmitted by the scheduled playback time of the image frame is determined. Further, the above transmission is realized by the distribution control unit 109 requesting the hierarchy information determined by the first reading unit 102. The distribution control means determines hierarchy information that can be transmitted by a predetermined time before the scheduled reproduction time of the image frame, so that it can be reliably reproduced at the scheduled reproduction time.

  FIG. 8 shows an example in which hierarchically structured stream data (moving image data) temporally structured into three layers by frame thinning is reproduced three times (first reproduction and two second reproductions). FIGS. 8A and 8B are explanatory diagrams for the first reproduction, stream reproduction, that is, first reproduction. At the time of the first reproduction, similarly to FIG. 7A, only layer information of layer 1 is transmitted (stream distribution) so as not to exceed the available transmission band BW1 of the network 203. The receiving device 204 decodes the hierarchical information transmitted by the display unit 110 and displays a moving image having a frame rate of 1/3.

  FIGS. 8C and 8D are explanatory diagrams of the second reproduction, that is, the first second reproduction, and FIGS. 8E and 8D are the third reproduction, that is, the second second reproduction. It is explanatory drawing of reproduction | regeneration. As shown in FIG. 8C, in the second reproduction for the first time, only layer information of layer 2 is transmitted (stream distribution) without exceeding the available transmission band BW1. Further, as shown in FIG. 8E, in the third reproduction (second second reproduction), only the data in layer 3 is transmitted (stream distribution) without exceeding the usable transmission band BW1. Further, the synthesizing unit 108 synthesizes the lower hierarchy information already received and accumulated on the receiving device 204 side with the received hierarchy information. Next, the display means 110 decodes and displays the moving image data having a frame rate of 2/3 in the second reproduction for the first time, and the moving image data without frame thinning in the second reproduction for the second time (display). (See FIGS. 8D and 8F).

  In the above transmission, first, the distribution control means 109 takes into consideration the information amount of this hierarchical information and the available transmission band BW1 from the hierarchical information not stored in the second storage means 106. Hierarchical information that can be transmitted by the scheduled playback time of the image frame is determined. Further, the transmission control unit 109 makes a request to the first reading unit 102 to realize the above transmission.

  In this way, each playback is configured to transmit (stream delivery) so as not to exceed the available transmission band, so that the second playback that improves the quality by increasing the resolution and frame rate for each playback without delay. realizable. Here, reproduction in which the spatial resolution and temporal resolution are improved every time reproduction is performed is referred to as progressive reproduction.

  FIG. 9 is an explanatory diagram of two reproductions in the conventional system. In FIG. 9A, the layer information data 402 of layer 1 is requested in the first reproduction, and the first reproduction is performed as shown in FIG. 9B. FIG. 9 (c) is a diagram showing transmission when the layer 2 + 3 is requested in the second reproduction after the first reproduction. In the first reproduction, since the usable transmission band is not exceeded, stream transmission / reproduction can be performed without delay (see FIG. 9A). However, as shown in FIG. 9C, when the layer information of layer 2 + 3 is requested to the first reading means 102 in the second reproduction, a delay occurs because it exceeds the available transmission band BW1 of the network 203. FIGS. 9C and 9D show this delay, and it can be seen that a reproduction waiting time has occurred until the reproduction is started.

  In this case, in order not to delay in the middle of reproduction, the received hierarchical information is stored in the second storage means 106 without immediately combining and displaying. After the first half of the moving image data is sufficiently accumulated, the hierarchy information of the hierarchy 1 + 2 + 3 accumulated in the second accumulation means 106 is read from the head of the reproduction target content, and is combined and displayed. Assuming that the bit rate of each layer is the same and that the available transmission band of the network can stream-distribute only one layer, reproduction cannot be started until half data is received after transmission (distribution) of layer 2 + 3 is started. It will be. For example, if the content has a playback time of 1 hour, it will wait 30 minutes before starting playback.

  FIG. 10 is a diagram showing transmission when the available transmission band BW2 of the network 203 changes during the distribution of moving image data. The schematic diagram on the upper side of FIG. 10A is an explanatory diagram for the first reproduction. At the time of the first reproduction, the available transmission band BW2 of the network 203 is a band that can transmit only one layer from the start of transmission to time T2, and is a band that can transmit two layers after time T2. To do. The distribution control means 109 checks the available transmission band BW2 of the network 203 and controls to transmit the hierarchy information up to the maximum hierarchy that does not exceed it. Accordingly, the hierarchical information data 402 of layer 1 (resolution 1/4 × 1/4) until time T2, and the hierarchical information data 402 of layer 1 + 2 (resolution 1/2 × 1/2) after time T2. Are transmitted without delay and reproduced by the receiving device 204. The schematic diagram on the left of FIG. 10B is an explanatory diagram of a moving image that is synthesized by the synthesizing unit 108 and displayed on the display unit 110 during the first reproduction, that is, the first reproduction.

  The schematic diagram in the middle of FIG. 10A explains the second playback, that is, the transmission of the second playback. In the second reproduction, it is assumed that the transmission band is capable of transmitting only two layers from the beginning to time T1, and only one layer after time T1. The distribution control unit 109 checks the layer information not stored in the second storage unit 106, and determines the amount of the layer information and the available transmission band BW2 of the network 203 before the scheduled playback time of each image frame. Determine the hierarchy information that can be transmitted. Further, the distribution control unit 109 requests the first reading unit 102 for the hierarchy information. In this case, control is performed to transmit (distribute) layer 2 + 3 from the beginning to time T1, layer 2 from time T1 to T2, and layer 3 after time T2.

  With the above transmission, as shown in the schematic diagram below FIG. 10A, in the second reproduction, that is, the second reproduction, the hierarchy is 1 + 2 + 3 (no resolution reduction) from the beginning to time T1, and the hierarchy from time T1 to T2. After 1 + 2 (resolution 1/2 × 1/2) and time T2, the layer information of layer 1 + 2 + 3 (no resolution reduction) becomes the second composition target. The moving images of these layers are played back without delay in the stream data playback system. In the schematic diagram below FIG. 10A, the horizontal axis represents time, the vertical axis represents the level of the hierarchy, and the combined hierarchy is represented by a solid line L1. In addition, the hierarchy information data corresponding to the hierarchy is represented by a box 402, and “(image frame number) :( hierarchy number)” is written in this box 402 (hereinafter, the horizontal axis represents time and the vertical axis represents Same for hierarchical graphs).

  In the above description, the distribution control unit 109 determines hierarchical information that can be transmitted by the scheduled reproduction time of each image frame. More specifically, it is necessary to determine the hierarchy information so that the synthesizing means 108 synthesizes the information and the display means 110 decodes and displays it in time for the scheduled reproduction time after transmitting the hierarchy information. Accordingly, the distribution control unit 109 determines hierarchical information that can be transmitted with a sufficient time for synthesis, decoding, and display. However, when it is necessary to synthesize the layer information transmitted immediately before, as in this case, it is necessary to allow for the above time, but when transmitting for the next playback as described later, There is no need to look at the time required for the synthesis, decoding and display.

  FIG. 11 is a diagram showing an operation screen for moving image reproduction displayed on the display device 219. The operation screen 40 includes a content selection button 41 for selecting moving image content to be reproduced, a reproduction content window 42 for reproducing and displaying a moving image, a reproduction operation button 43 for performing standard reproduction and special reproduction, and a quality box for displaying the current reproduction quality. 44, a playback time box 45 for displaying the recording time of the object currently being played back, and a time bar 46 indicating which recording time is being played back as a whole. When the content selection button 41 is clicked, the display unit 110 displays a selection box having a list of moving image content stored in the transmission device 202 on the display device 219. Next, the moving image content to be reproduced is selected by the user with reference to the content information and the like, and is input to the reproduction request unit 220. Further, the receiving device 204 requests the distribution control unit 109 to reproduce the content. In addition, the playback quality box 44 displays, for example, the number of hierarchies currently being played back and the bit rate as the playback quality.

  FIG. 12 is a processing flow showing the processing procedure of the present embodiment. In step S1, the moving image playback mode is started and the operation screen 40 of FIG. 11 is displayed. In step S2, moving image content to be reproduced by the user is selected. In step S3, the distribution control unit 109 performs distribution connection processing for distributing the selected moving image content in a stream, and establishes a distribution channel.

  In step S4, the content of the reproduction request when the user operates the reproduction operation button is determined. If the content of the playback request is not pause or playback end, playback parameters such as playback direction (forward or reverse direction) and playback speed (standard or N times speed, etc.) are set in step S7. In step S8, the distribution control means 109 determines the next image frame to be transmitted and reproduced based on the set reproduction parameter. For example, if the standard speed is set in the forward direction, the next image frame is determined as the image frame to be transmitted and reproduced, and if the quadruple speed is set in the reverse direction, the image frame four frames before is determined.

  In step S9, the distribution control unit 109 checks the available transmission band of the network 203 and the hierarchical information of the moving image stored in the second storage unit 106, and determines the hierarchical information to be transmitted and the transmission timing. . More specifically, the distribution control unit 109 takes the image frame from the layer information not stored in the second storage unit 106 in consideration of the information amount of the layer information and the available transmission band BW1. Hierarchical information that can be transmitted by a predetermined time before the scheduled reproduction time is determined. The term “predetermined time” means that there is a margin for the time required for combining, decoding, and displaying. The predetermined time is the time required for combining, decoding, and displaying when the transmitted hierarchical information is combined and displayed. When transmitting non-combined hierarchical information, the predetermined time is set to 0. To do. By determining the hierarchy information to be transmitted by setting the predetermined time in this way, the stream data reproduction system can reliably reproduce after transmission and does not display the transmitted hierarchy information when displaying the transmitted hierarchy information. Has the effect of transmitting as much hierarchical information as possible and storing it in the second storage means 106.

  In step S10, the first reading unit 102 reads the corresponding hierarchy information from the first storage unit 101 in accordance with the instruction from the distribution control device 109, and transmits the hierarchy information at the timing when the transmission unit 103 is instructed. In step S11, the receiving means 105 receives the hierarchy information, and accumulates the hierarchy information received by the second accumulation means 106.

  In step S <b> 12, the second reading unit 107 reads out the lower layer information corresponding to the received image frame of the layer information from the second storage unit 106. Further, in step S13, the synthesizing unit 108 synthesizes the received hierarchy information and the read hierarchy information. In step S <b> 14, display means 110 decodes the synthesized image and displays it on display device 219.

  If the end of playback has not been reached in step S15 (if it is forward playback, it is the last image frame of the moving image content, and if it is backward playback, it is not the top frame of the moving image content), a playback request is made in step S16. The means 220 checks whether there is a new reproduction request from the user. If there is no reproduction request, the stream data reproduction system continues the reproduction process of steps S8 to S16. If the playback end is reached in step S15 or if there is a playback request in step S16, the process of step S4 is performed.

  If there is a pause request in step S4, the delivery control means 109 pauses transmission (stream delivery) from the transmission apparatus 202 in step S5 and waits for a new playback request.

  If there is a reproduction end request in step S4, the distribution control means 109 closes the distribution channel and disconnects the distribution in step S6, and determines the end of the moving image reproduction mode in step S17. If not finished, the user waits for content selection from the user in step S2, and if finished, ends the moving image playback mode in step S18.

  According to the configuration of the present embodiment, the distribution control unit 109 can perform stream transmission based on the available transmission band of the network 203 and the hierarchical information stored in the second storage unit 106 in response to a moving image playback request. Therefore, it is possible to improve the quality each time the second reproduction is repeated and to reproduce the stream data without delay, because the hierarchical data is determined and only the hierarchical information is distributed in a limited transmission band.

  Further, the distribution control means 109 constantly checks the available transmission band of the network 203 to determine the hierarchy information to be transmitted, so that the available transmission band of the network 203 changes during the first reproduction or the second reproduction. However, the maximum hierarchical data that can be transmitted in response to the change is transmitted. As a result, the stream data reproduction system can perform progressive reproduction using the bandwidth without waste.

  Furthermore, according to the configuration of the present embodiment, the user does not need to explicitly specify the display quality (hierarchy of data to be displayed) as in the conventional example, but operates the playback operation button on the operation screen as desired. It is possible to observe a high-quality moving image within the range of the usable transmission band and to improve the operability by simply reproducing the portion.

Embodiment 2. FIG.
Although the first embodiment is configured to transmit hierarchical data used for each reproduction within the range of the transmission band that can be used by the network 203, this embodiment is not used in the current reproduction. Hierarchical data used in subsequent playback is transmitted within the available transmission band of the network 203 without interfering with the current playback. The system configuration diagram in FIG. 2 and the processing flow in FIG. 12 are the same as those in the first embodiment. Mainly, different parts of the processing of the distribution control unit 109 will be described below.

  Depending on the situation, the distribution control means 109 of the present embodiment does not synthesize with the second reproduction at the time of transmission, but does not synthesize the hierarchy information reproduced after the next second reproduction to the first reading means 102. A read request is made. As an example of the above situation, there is a case where the second storage means 106 has already stored the hierarchical information corresponding to the quality in the mode of reproducing with the same quality. An example of the above situation is shown below.

  The synthesizing unit 108 according to the present embodiment synthesizes the hierarchy according to the hierarchy of the hierarchy information accumulated in the second accumulation unit 106 corresponding to the stream data at the recording time for a predetermined time from the recording time of the second reproduction target. Decide the level. Also, the distribution control means 109 determines the time required for the composition means 108 to compose the time required for the composition means 108 and the time required for the display means 110 to display when the hierarchy information at the above-mentioned hierarchy level is not accumulated in the second accumulation means 106. The total time. Further, when the hierarchical information of the hierarchical level is stored in the second storage means 106, the predetermined time is set to zero. Further, the delivery control unit 109 determines the amount of information that can be transmitted from the hierarchical information not stored in the second storage unit 106 using the available transmission band of the transmission path 104 up to the predetermined time before the scheduled reproduction time. Select the hierarchy information you have. Further, the distribution control unit 109 requests the first reading unit 102 for the selected hierarchy information. Instead of setting the predetermined time to 0, it may be a time to store the received information in the memory. Furthermore, it is preferable because the accuracy is increased.

  FIG. 13 is a diagram illustrating an example of transmission within the available transmission band BW2 of the network 203, including hierarchical information used in subsequent playback. The upper two schematic diagrams of FIG. 13A show the time transition of the transmission band at the first transmission, the layer information to be transmitted, and the layer information reproduced at the first reproduction. As shown in the schematic diagram at the top of FIG. 13A, in the first reproduction of the first time, since the transmission band BW2 can be distributed in one layer from the start of transmission to time T1, the transmitting apparatus 202 The data 402 of the hierarchical information is transmitted. After time T1, the transmission apparatus 202 transmits the data 402 of the hierarchy information of the hierarchy 1 + 2 because it is the transmission band BW2 that can be distributed in two layers. During the first reproduction, all received data is accumulated in the second accumulation means 106. When the display mode is set to the same quality (hierarchy), as shown in the schematic diagram in the second stage from the top in FIG. 13 (a), it depends on the change in the available transmission band BW2 of the network 203. First, the receiving apparatus 204 reproduces only the data 402 of the hierarchy information of the hierarchy 1 (see the explanatory diagram on the left side of FIG. 13B).

  The schematic diagram in the lower two stages of FIG. 13A is an explanatory diagram of the second reproduction, that is, the first second reproduction, and the transmission band and the layer information transmitted during the first second reproduction transmission. And the time transition of the hierarchical information reproduced in the first second reproduction. In this case, as shown in the schematic diagram in the second stage from the bottom of FIG. 13A, the transmitting apparatus 202 stores the layer 402 data 2 + 3 in the transmission band BW2 that can be distributed in two layers from the start of transmission to time T1. To transmit. Further, after time T1, the layer information data 402 of layer 3 is transmitted in the transmission band BW2 that can be distributed in one layer. In this case, since the receiving device 204 has the data of layers 1 to 3 for the recording time to be reproduced, as shown in the lowermost schematic diagram of FIG. 13A, at the time of the second reproduction, the data of layers 1 + 2 + 3 Display can be performed with the same quality (see the explanatory diagram on the right side of FIG. 13B).

  In this example, at the time of the first transmission, the distribution control means 109 does not synthesize after the second reproduction at the time T1 but synthesizes and reproduces after the next second reproduction. A read request is made to the first reading means 102 for the hierarchy information. At this time, the selection criterion for the hierarchical information to be transmitted is set to 0 when the hierarchical information at the hierarchical level is stored in the second storage means 106. By setting the predetermined time to 0, hierarchical information having a larger amount of information transmitted by the scheduled reproduction time in the transmission band can be selected, and hierarchical information of a higher hierarchy can be selected. In addition, the distribution control unit 109 selects from the hierarchy information that is not stored in the second storage unit 106 as in the first embodiment.

  Further, after time T1 of the first second reproduction, this corresponds to the case where the hierarchical information of the hierarchical level is stored in the second storage means 106, and the hierarchical information is selected by setting the predetermined time to 0. Further, the second reproduction of the second time corresponds to the case where the hierarchical information at the hierarchical level is not stored in the second storage means 106 both before the time T1 and after the time T1, and the distribution control means Hierarchy information is selected by setting a total time of the time to be combined and the time required for display on the display means 110 as a predetermined time.

  In the mode of reproducing with the same quality, at the start of the transmission of the first reproduction of the first time, if only one layer can be transmitted after the time T1, the second reproduction, that is, the second reproduction, It can be displayed only in the quality of level 1 + 2. On the other hand, in the example of FIG. 13 of the present embodiment, higher-quality display of the hierarchy 1 + 2 + 3 is possible in the second reproduction (second reproduction) (see FIG. 13C).

  As described above, by transmitting the hierarchical information to be reproduced after the next time within the transmission band BW2 at the time of each reproduction, it is possible to perform high-quality reproduction such as higher resolution in the subsequent reproduction.

  As another form, a mode that always reproduces with the highest quality is conceivable instead of a mode that reproduces with the same quality. In this mode, the distribution control means 109 first selects hierarchy information with a predetermined time of 0. Next, when the information amount of this hierarchical information is less than the first information amount that can be transmitted with the total time of the combining time of the combining means 108 and the time required for display of the display means 110 as a predetermined time, the distribution is performed. The control means 109 makes it possible to reproduce the hierarchy information at the scheduled reproduction time. On the other hand, if the amount of information is equal to or greater than the first information amount and less than the second information amount that can be transmitted with a predetermined time of 0, the distribution control means 109 allows the hierarchy information to be reproduced after the next second reproduction. The synthesizing unit 108 is configured to synthesize the hierarchy information that can be reproduced.

  According to this configuration, in the first second reproduction of FIG. 13A, if the amount of information is less than the first information amount that can be transmitted after time T1 and before the predetermined reproduction time, reproduction is performed up to layer 2. can do. In addition, the distribution control unit 109 selects hierarchical information with a predetermined time of 0 (which can be transmitted by the scheduled reproduction time), and the combining unit 108 has completed transmission by the predetermined time before the scheduled reproduction time. It is also possible to compose the hierarchical information so that the display means 110 displays it. According to this configuration, there is an effect that the control is simplified.

  As described above, in the mode in which the reproduction is always performed with the highest quality, the above-described configuration enables the reproduction with the highest possible quality, that is, the higher hierarchy information.

  FIG. 14 is a diagram illustrating another example in which transmission is performed within an available transmission band of the network 203 including hierarchical information used in subsequent playback. In this example, it is assumed that the available transmission band of the network 203 is a transmission band BW1 in which data for 1.5 layers can be stream-distributed, and is a mode for displaying with the same quality during reproduction. FIG. 14 is an explanatory diagram of the first transmission and reproduction. In FIG. 14 (a), the transmitting apparatus 202 receives the hierarchy information data 402 of the hierarchy 1 by the reproduction time of the odd-numbered image frame, and the hierarchy information data of the hierarchy 1 + 2 by the reproduction time of the even-numbered image frame. 402 is transmitted (see the upper diagram in FIG. 14), and all received data is accumulated on the receiving device 204 side (see the middle diagram in FIG. 14). Along with this accumulation, the receiving apparatus 204 reproduces only the hierarchy information data 402 of the hierarchy 1 (see the lower diagram of FIG. 14 and FIG. 16A).

  FIG. 15 is an explanatory diagram of the second transmission and reproduction in the above case. As shown in the upper part of FIG. 15, in the second transmission, the transmission apparatus 202 transmits layer 2 + 3 for odd-numbered image frames and layer 3 for even-numbered image frames. Then, as shown in the middle part of FIG. 15, the layer information data 402 of layers 1 to 3 is arranged in the second storage unit 106 on the receiving device 204 side. Therefore, as shown in the lower part of FIG. 15, the synthesizing unit 108 synthesizes the hierarchy information of the hierarchy 1 + 2 + 3, and the display unit 110 can display the same resolution as the original image corresponding to the hierarchy 1 + 2 + 3 (FIG. 16B). )reference.).

  In the playback mode with the same quality, when the available transmission band BW1 of the network 203 can use only the transmission band for 1.5 layers, the conventional method transmits only one layer and the second playback, That is, in the second reproduction, the display can be performed only with the quality of the hierarchy 1 + 2. On the other hand, in the present embodiment, the distribution control unit 109 first transmits the layer information that can be transmitted by the scheduled reproduction time within the transmission band BW1 from the layer information that is not stored in the second storage unit 106. Request to the reading means 102. As a result, layer information of two layers is transmitted every other image frame, and in the example of FIGS. 14 and 15, higher quality display of layers 1 + 2 + 3 can be performed in the second reproduction.

  The distribution control unit 109 can also be configured to select hierarchical information corresponding to an image frame at a recording time different from the reproduction target when determining the hierarchical information to be transmitted. In this configuration, the distribution control unit 109 first examines the image frame that goes back the recording time, and only the hierarchy information that is lower than the layer corresponding to the current reproduction target image frame is stored in the second storage unit 106. Examine the image frame. Next, it is possible to incorporate a control in which the distribution control means 109 preferentially requests transmission of hierarchical information corresponding to the traced image frame. As a result, the level of the hierarchy of each image frame stored in the second storage unit 106 becomes nearly uniform, and there is an effect of improving the reproducible quality in the mode of reproducing with the same quality. However, the number of image frames that go back the recording time from the relationship of processing time needs to be limited to a predetermined frame.

  FIG. 17 is a diagram illustrating another example of transmission within the available transmission band BW2 of the network 203, including hierarchical information used in the subsequent playback. The distribution control unit 109 controls to transmit hierarchical information that is a difference between image frames corresponding to each reproduction timing by using all the available transmission bands BW2 of the network 203. When the fluctuation of the transmission band BW2 is severe, if all the hierarchy information received by the receiving device 204 and the hierarchy information stored in the second storage means 106 are combined and displayed, the reproduction quality changes frequently. The playback image becomes very difficult to see, such as a large change. Therefore, the synthesizing means 108 does not synthesize all received hierarchy data, but selects and synthesizes hierarchy information so that the reproduction quality changes smoothly.

  In the example of FIG. 17, in the first transmission, there are mixed image frames in which the data 402 of the hierarchy information can be transmitted only to the hierarchy 1, the hierarchy 2, and the hierarchy 3 (see the upper diagram in FIG. 17). In the means 106, hierarchical information with different accumulated levels is accumulated and mixed (see the middle diagram of FIG. 17). In this case, since the synthesizing means 108 selects and synthesizes the hierarchy information so that only one hierarchy changes between adjacent frames and the same hierarchy continues for 3 frames or more, as shown in the lower diagram of FIG. In addition, the hierarchy information of the hierarchy 1 and the hierarchy 1 + 2 is reproduced. In this case, the image frames 4 to 7 are stored in the second storage means up to level 3, but the level information of level 1 + 2 is reproduced.

  FIG. 18 is a diagram for explaining the second reproduction in the example of FIG. In this example, as a result of the transmission band BW2 changing drastically (see the upper diagram in FIG. 18), image frames 1 to 3 are stored in the second storage means 106 up to layer 3, and image frame 7 is stored in layer 6 Is stored in the second storage means 106 (see the middle part of FIG. 18). In this case, when the above-described control of the synthesizing unit 108 is performed, the image frame 7 is accumulated up to the hierarchy 6, but the hierarchy up to the hierarchy 4 is reproduced (see the lower diagram in FIG. 18).

  Based on the available transmission band of the network 203 and the layer information stored in the second storage unit 106, the distribution control unit 109 determines the layer information used for current playback and future playback as layer information to be transmitted. . When the fluctuation of the transmission band of the network 203 or the jitter (dispersion) of the transmission delay is large, it is necessary to reliably control the distribution so that the current reproduction is reproduced without being delayed in the middle. In general, the receiving apparatus 204 includes a reproduction buffer that accumulates reproduction data while allowing a slight delay in order to absorb transmission delay jitter. Considering the state of the reproduction buffer, when the remaining amount of the buffer is small, the current reproduction is preferentially transmitted. In addition, if the remaining buffer capacity is large, a control for increasing the hierarchical information used for future playback is added to make the current stream playback more reliable and necessary for future playback using the available bandwidth. Hierarchical information can be transmitted.

  Next, in the processing flow of FIG. 12 of the first embodiment, a different part of the processing in this embodiment will be described. Here, the processing is different between the mode for reproducing with the same quality and the mode for reproducing with the highest quality, and will be described separately.

  In the configuration of the mode for reproducing with the same quality, in step S9, the synthesizing unit 108 stores the hierarchy stored in the second storage unit 106 corresponding to the recording time for a predetermined time from the recording time of the second reproduction target. The hierarchy level to be combined is determined according to the information hierarchy. In step S9, the synthesizing unit determines a hierarchy level to be synthesized in accordance with the hierarchy of the hierarchy information accumulated in the second accumulation unit 106. Specifically, first, the stream data stored in the second storage means 106 corresponds to the recording time from the recording time of the next second reproduction target to the recording time after a predetermined time has elapsed. Select the stream data to be used. Next, the hierarchical level in which the stream data corresponding to each recording time is accumulated can be checked, and the hierarchical level can be obtained by synthesizing a value obtained by adding one hierarchical level to the lowest hierarchical level. At this time, if the adjustment is made so that the change is reduced as much as possible by referring to the hierarchical level synthesized in the most recent second reproduction, the reproduction quality does not change frequently and becomes easy to see.

  Also, in step S9, the distribution control means 109 can transmit data up to a predetermined time before the scheduled reproduction time of the image frame when the hierarchy information at the hierarchy level is not accumulated in the second accumulation means 106. Determine hierarchy information. More specifically, the distribution control unit 109 can transmit a hierarchy from the layer information not stored in the second storage unit 106 in consideration of the information amount of the layer information and the available transmission band BW1. Decide information. The predetermined time is a time required for internal processing, and is obtained by summing the time required for combining by the combining means 108 and the time required for display by the display means 110. On the other hand, when the hierarchy information at the hierarchy level is accumulated in the second accumulation means 106, the distribution control means 109 determines the hierarchy information to be transmitted with the predetermined time as 0. By determining the hierarchy information to be transmitted by setting the predetermined time in this way, when the transmitted hierarchy information is displayed, it can be reliably reproduced after transmission, and when the transmitted hierarchy information is not displayed, it is a little more. There is an effect that the hierarchical information can be transmitted and stored in the second storage means 106.

  In step S13, the synthesizing unit 108 synthesizes up to the hierarchy information at the hierarchy level determined in step S9. As a result, the reproduction quality is the same, but the second storage means 106 stores the hierarchical information corresponding to the recorded time of reproduction, and the hierarchical information higher than the hierarchy of the information to be reproduced. In step S9, a higher hierarchical level can be selected.

  Next, the processing flow in the mode for reproducing the highest quality will be described. In the configuration of the mode for reproducing the highest quality, step S8 is the same as that in the first embodiment. In step S9, the distribution control unit 109 determines the layer information that can be transmitted from the layer information not stored in the second storage unit 106 up to a predetermined time before the scheduled playback time of the image frame. When determining this hierarchical information, the information amount of this hierarchical information and the available transmission band BW1 are considered. Specifically, first, the hierarchical information that can be transmitted in the transmission band BW1 is selected with the predetermined time being 0. If the information amount of the hierarchical information is less than the first information amount transmitted with the total time of the combining time of the combining means 108 and the time required for display of the display means 110 being transmitted as a predetermined time, the hierarchical information is “Immediate playback is possible” at the scheduled playback time. If the amount of information is equal to or greater than the first information amount and less than the second information amount transmitted with a predetermined time of 0, the hierarchy information is reproducible after the next second reproduction (“reproducible after next time”). Furthermore, two types of attributes “immediate reproduction possible” and “reproducible next time” determined by the information amount are added to the hierarchical information accumulated in the second accumulation means 106.

  In step S13, the synthesizing unit 108 selects hierarchy information to be synthesized from the hierarchy information to which the attribute “immediate reproduction is possible” is added. Here, the hierarchy information to which the attribute “reproducible from next time” is added is changed to “immediately reproducible” after combining the hierarchy information other than the hierarchy information. As a result, the hierarchical information that can be combined, decoded, displayed, and displayed at the scheduled playback time is combined. Further, hierarchy information that cannot be played back in time for the scheduled playback time (hierarchical information with the attribute “reproducible from next time”) is transmitted until the scheduled playback time, and is combined and displayed in the second playback after the next playback. Therefore, while the hierarchy information that can be reproduced at the scheduled reproduction time is reliably reproduced, more hierarchy information can be accumulated in the second accumulation means 106 by effectively using the synthesis, decoding, and display times, and the next and subsequent times. This has the effect of improving playback quality.

  According to the configuration of the present embodiment, the distribution control means 109 transmits within the transmission band of the network 203 including the layer information necessary for the second reproduction after the next time in addition to the layer information necessary for the current reproduction. Determine possible hierarchy information. Therefore, the transmission bandwidth of the network 203 is further effectively used, and there is an effect of enabling high quality display even at a stage where the number of reproduction repetitions is small.

  Further, in the mode of reproducing with the same quality, if the hierarchy information of this hierarchy level is not stored in the second storage means 106 after the hierarchy level to be played back is determined, the predetermined time is set by the composition means 108. The distribution control unit 109 selects hierarchical information having an information amount that can be transmitted by a predetermined time before the scheduled reproduction time, as the total time of the display time and the time required for display on the display unit 110. On the other hand, when the hierarchical information of the hierarchical level is stored in the second storage unit 106, the distribution control unit 109 selects hierarchical information having an information amount that can be transmitted by the scheduled reproduction time. Therefore, according to the configuration of the present embodiment, even if the reproduction quality is the same, it is accumulated above the hierarchy of the hierarchy information to be reproduced, and a higher hierarchy level can be selected in the second and subsequent reproductions, and the number of reproduction repetitions There is an effect that a high-quality display can be performed at a stage where there is little.

  Furthermore, in the mode for reproducing the highest quality, the distribution control means 109 first selects hierarchical information having an information amount that can be transmitted by the scheduled reproduction time. When the information amount of the hierarchical information is less than the first information amount transmitted with the total time of the time for combining by the combining means 108 and the time required for display by the display means 110 being transmitted as a predetermined time, the distribution control means 109 enables immediate reproduction of the hierarchy information. On the other hand, if the information amount of the hierarchy information is greater than or equal to the first information amount, the distribution control means 109 makes it possible to reproduce the hierarchy information from the next time. Therefore, according to the configuration of the present embodiment, it is possible to reliably reproduce the highest hierarchy level hierarchy information that can be reproduced at the scheduled reproduction time, and to effectively use the synthesis, decoding, and display time to obtain more hierarchy information. This is effective for improving the reproduction quality after the next time.

  In addition, since the hierarchical information to be combined is selected and combined from the hierarchical information received by the receiving device 204 and stored in the second storage unit 106 so that the reproduction quality does not change significantly, the combined information is selected. According to the configuration, it is possible to reproduce a visually smooth image even if the transmission band fluctuates drastically.

  Further, by adjusting the determination of the layer information used for the current reproduction and the future reproduction in consideration of the state of the reproduction buffer of the receiving apparatus 204, even when the jitter of the transmission delay is severe, According to the configuration, there is an effect that the current stream reproduction and the second reproduction can be reliably performed.

Embodiment 3 FIG.
In the present embodiment, when a pause request occurs during playback, the remaining hierarchical information about the stream data at the recording time of the paused image frame (referred to as the pause recording time), or before and after the pause recording time Layer data required for the next and subsequent playbacks, such as stream data, is transmitted. The system configuration of FIG. 2 is the same as that of the first embodiment, and only the different parts in the processing of the distribution control unit 109 will be described below.

  FIG. 19 is a diagram for explaining a function (hereinafter referred to as “progressive still”) for sequentially increasing the resolution of a still image when a reproduction request for pause is generated from the reproduction request unit 220. When receiving a pause request at time T1, the distribution control unit 109 stops the distribution of the hierarchical information that has been performed. Next, the distribution control means 109 transmits the layer 2 layer information of the image frame N corresponding to the recording time (pause recording time) of the stream data reproduced at the time of suspension so as to transmit at time T1 + 1. A request is made to the first reading means 102 (see the upper diagram in FIG. 19A). On the receiving device 204 side, the received hierarchy information is accumulated in the second accumulation means 106, and the synthesizing means 108 synthesizes the hierarchy information of the hierarchy 1 to decode the hierarchy 1 + 2 image and display it on the display device 219 ( (Refer to FIG. 19A, the lower diagram and FIG. 19B.) Further, at time T1 + 2, a request is made to the first reading unit 102 to transmit the layer 3 layer information of the image frame N, and the reception device 204 side similarly stores the received data in the second storage unit 106. At the same time as the accumulation, the combining unit 108 combines the layer 3 hierarchy information with the layer 1 + 2 layer information, and the display unit 110 decodes the layer 1 + 2 + 3 image and displays it on the display device 219.

  According to the above configuration, when the user selects the pause button on the operation screen, the paused low-resolution still image is sequentially updated and displayed as a high-resolution image. Generally, the image quality perceivable by humans in moving image display is lower than the image quality perceivable in still image display. Also, important scenes discovered during video playback are often paused and observed in detail. From the above, it is effective to improve the image quality of the image frame at the time of pause than the image quality at the time of moving image display. In the present embodiment, even when there is no special user operation, the hierarchical information is transmitted using the transmission band of the network 203 that is vacated by the suspension, and the image frame quality at the time of suspension is displayed when the moving image is displayed. It automatically improves the image quality.

  FIG. 20 is a diagram showing an example of distributing and accumulating the layer information data 402 of the frame before the pause in preparation for the next and subsequent playback when a pause playback request is generated. When receiving a pause request at time T1, the distribution control unit 109 stops the distribution of the hierarchical information that has been performed. Next, the distribution control unit 109 applies the remaining layer 2 data to the image frame N at the time of suspension (image frame corresponding to the recording time N) and the image frame before the time of suspension from time T1 + 1. The first reading means 102 is requested to transmit sequentially (see FIG. 20A). On the receiving device 204 side, the hierarchical information received by the receiving means 105 is only stored in the second storage means 106, and the composition and display processing is not performed until the next reproduction request is made (the lower part of FIG. 20 (a)). And FIG. 20 (d)).

  It is assumed that at time T1 + M, a reproduction request is issued from the reproduction request unit 220 at a time point that is earlier than the temporary stop point. FIG. 20B shows the hierarchical information stored in the second storage means 106 at time T1 + M-1. The distribution control unit 109 requests the first reading unit 102 to sequentially distribute the layer information of the remaining layer 3 from the image frame (NM) (the image frame corresponding to the recording time (NM)). (Refer to the upper diagram in FIG. 20C.) Specifically, the distribution control unit 109 requests the first reading unit 102 to transmit the layer information of the layer 3 of the stream data corresponding to the recording time after the recording time (N−M) in order of the recording time. On the receiving device 204 side, the received data is stored in the second storage means 106. At the same time as the accumulation, the reception apparatus 204 synthesizes the already accumulated hierarchy information of the hierarchy 1 + 2 and the read data of the hierarchy 3, decodes the image of the hierarchy 1 + 2 + 3, and displays it on the display device 219 (FIG. 20). (C) Refer to the lower figure and FIG.

  If only the distribution is stopped at the time of the pause, the system can reproduce only the image of the hierarchy 1 + 2 retroactively from the pause point. However, by adopting a configuration in which the layer 2 layer information corresponding to the recording time retroactive to the past is transmitted and stored during the pause period, the stream data playback system allows the layer 1 + 2 + 3 image during the second playback. Can be played. When an important event or an abnormal event is found during video reproduction, it is often necessary to review an image that has been traced back to the past from the time of the pause, and the transmission device 202 uses the transmission band that is freed by the pause. The hierarchical data of the section that is likely to be reproduced next is transmitted in advance and the receiving apparatus 204 accumulates it.

  In FIG. 20, the hierarchical data of the image traced back from the paused image frame is configured to be transmitted. However, the distribution control unit 109 is configured to transmit the past image or the past image or the like according to the reproduction direction such as forward reproduction or reverse reproduction. You may comprise so that hierarchy information may be requested | required about a future image. In addition, there is a case where there is a case where there is no abnormality although there is a case where there is an anxiety during the reproduction of the moving image and the pause is confirmed. In this case, in order to resume the reproduction as it is, the distribution control means 109 may transmit the hierarchical data for a section before and after a predetermined pause. Further, when a sensor alarm or the like occurs during a predetermined time interval before and after the temporary stop, the distribution control means 109 may be configured to preferentially transmit the stream data hierarchy information before and after the alarm.

  FIG. 21 is a processing flow showing a processing flow of the present embodiment. When the reproduction request is other than the pause, the process flow is the same as that shown in FIG. 12, and therefore only the process during the pause will be described here.

  If there is a pause request in step S4, the distribution control means 109 stops the distribution so far in step S5. Further, the distribution control unit 109 determines an image frame (recording time) to be transmitted in step S20 according to the progressive still or the image data transfer mode before the suspension. In step S 21, the distribution control unit 109 determines the hierarchy information to be transmitted based on the available transmission band of the network 203 and the hierarchy information stored in the second storage unit 106, and reads it to the first reading unit 102. The instructions are given.

  In step S22, the first reading unit 102 reads the corresponding hierarchical data from the first storage unit 101, and the transmitting unit 103 transmits the hierarchical information. In step S23, the receiving unit 105 stores the received hierarchy information in the second storage unit 106.

  In step S24, mode determination is performed, and when the mode is progressive still, the second reading unit 107 reads the hierarchical information of the corresponding image frame stored in the second storage unit 106. Further, in step S26, the synthesizing unit 108 synthesizes, and in step S27, the display unit 110 decodes and displays it on the display unit 304. If the mode is not progressive still, the receiving apparatus 204 does not perform the composition and display processing. In step S28, the distribution control means 109 waits for a new reproduction request if there is no hierarchical information to be transmitted. If the hierarchy information to be transmitted remains, the distribution control means 109 checks in step S29 whether there is a new reproduction request. If there is no hierarchy information, the processing in steps S20 to S28 is repeated to create a new reproduction. If there is a request, the process of step S4 is performed.

  According to this configuration, when the distribution control unit 109 receives a pause reproduction request, the distribution control unit 109 stops the current stream transmission and transmits the remaining hierarchical information for the image frame data at the time of the pause. It is controlled and combined with the received hierarchical information on the receiving device 204 side and displayed. With this configuration, the display of the image frame at the time of suspension can be progressively updated to a high quality image and displayed. Note that the configuration may be such that stream transmission is not stopped. In this case, the basic hierarchy information corresponding to the recording time of the period from the pause to the next reproduction start can be accumulated, and when there is a reproduction request for this period, it is possible to reproduce with high quality There is. In addition, if the stream transmission is stopped at the time of pause, the transmission bandwidth is widened and other layer information can be accumulated, so that layer information can be stored without waiting for playback at the next second playback, There is an effect that high-quality reproduction is possible.

  Further, according to this configuration, when the distribution control unit 109 receives a request for a pause request, it is synthesized and reproduced after the next second reproduction in the period until the next second reproduction is requested. Therefore, the hierarchical information is stored in the second storage unit 106. Therefore, there is an effect that high-quality reproduction is possible without waiting for reproduction at the next second reproduction.

  Further, according to this configuration, when the distribution control unit 109 receives the pause request, the distribution control unit 109 has a time close to the recording time of the paused playback target during the period until the next playback is requested. A read request is made in order from the hierarchy information. With this configuration, the second storage means 106 stores hierarchical information close to the recording time at which it was temporarily stopped. Accordingly, the hierarchical information stored in the period is reproduced with a high probability at the next second reproduction, and there is an effect that high-quality reproduction can be performed without waiting for reproduction at the next second reproduction.

  Also, when the distribution control means 109 receives a pause reproduction request, the distribution control means 109 controls to stop the stream transmission performed until the pause, and to transmit the hierarchy information necessary for the next and subsequent reproductions. The hierarchical information received on the 204 side is accumulated. According to this configuration, efficient progressive playback is realized using the period from the pause to the start of the next playback, and more effectively using the transmission band of the network 203.

  In the above-described embodiment, description has been made using hierarchical structured stream data based on spatial resolution and frame thinning. However, other hierarchical structured stream data such as SNR (Signal Noise Ratio) and color components may be used. These types of hierarchical structures may be used in combination. Also, how playback is performed using hierarchical structure, for example, playback policies such as motion priority and image quality priority are defined, playback policies selected by the user during playback, available transmission bandwidth of the network 203, second The distribution control unit 109 may determine the hierarchy information requested to the first reading unit 102 based on the status of the hierarchy information stored in the storage unit 106.

  The first storage means 101 stores stream data that is hierarchically structured. However, stream data that is not hierarchically structured is stored in the first storage means 101, and the stream data that is read out every time a request is structured. The hierarchy information requested by the distribution control means 109 may be transmitted.

  The second accumulating unit 106 may have a cache function for erasing from hierarchical information with low priority according to the capacity of the storage unit on the receiving device 204 side. For example, the priority may be erased from the highest hierarchical number, erased from an image frame accumulated in the past, or prioritized in the section before and after the alarm alarm.

  Although this embodiment has been described using moving image data captured by the camera 101, it can also be applied to an edited moving image or an artificial image such as an animation. In addition, the present embodiment can be applied to other time-series stream data such as audio and measurement data regardless of the image stream as long as the stream data can be hierarchically structured, and similar effects can be obtained.

FIG. 3 is a block configuration diagram of the first embodiment. 1 is a system configuration diagram according to Embodiment 1. FIG. FIG. 2 is a hardware configuration diagram of the apparatus according to the first embodiment. It is explanatory drawing of the stream data made into hierarchical structure. It is explanatory drawing of the data structure recorded on a 1st storage means. It is explanatory drawing of the data structure recorded on a 2nd storage means. 6 is an explanatory diagram of progressive reproduction of stream data that is hierarchically encoded with spatial resolution according to Embodiment 1. FIG. 6 is an explanatory diagram of progressive playback of stream data that is hierarchically encoded with temporal resolution in Embodiment 1. FIG. It is explanatory drawing in the case of transmitting a difference without considering a transmission band in a conventional system. 6 is an explanatory diagram of progressive playback of a moving image when the available network bandwidth changes in time according to Embodiment 1. FIG. 6 is an explanatory diagram of an operation screen in Embodiment 1. FIG. 3 is a processing flow in the first embodiment. FIG. 10 is an explanatory diagram of progressive reproduction of stream data when data necessary for future reproduction is transmitted in the second embodiment. FIG. 10 is an explanatory diagram of the first reproduction in the progressive reproduction of a moving image that also transmits data necessary for future reproduction in the second embodiment. FIG. 10 is an explanatory diagram of the second reproduction in the progressive reproduction of a moving image that also transmits data necessary for future reproduction in the second embodiment. FIG. 11 is a conceptual diagram for explaining the progressive playback of moving images when data necessary for future playback is also transmitted in the second embodiment. FIG. 10 is an explanatory diagram of progressive playback of moving images when data necessary for future playback is also transmitted in the second embodiment. FIG. 10 is an explanatory diagram of progressive playback of moving images when data necessary for future playback is also transmitted in the second embodiment. FIG. 10 is an explanatory diagram of progressive stillness that sequentially increases the resolution of a still image that is paused in the third embodiment. FIG. 10 is an explanatory diagram of a process for distributing and storing hierarchical data of a frame before suspension during a suspension period in the third embodiment. It is a processing flow of Embodiment 3.

Explanation of symbols

101 First accumulating means, 102 First reading means, 103 Transmitting means, 104 Transmission path, 105 Receiving means, 106 Second accumulating means, 107 Second reading means, 108 Combining means, 109, 214, 221 Distribution control means, 110 Display means 201 Camera 202 Transmission device 203 Network 204 Reception device 206 Shooting means 207 Encoding means 208 Camera transmission means 209 Information reception means from the camera 211 Hierarchical stream data 219 Display device 301 Input unit, 302 Storage unit, 303 Central processing unit, 304 Display unit, 305 Communication unit, 530, 630 Stream entity data, 531, 631 Stream management data.

Claims (8)

First accumulation means for accumulating hierarchical information that is information of each hierarchy obtained by hierarchically encoding time-series stream data;
First reading means for reading out the hierarchy information from the first storage means;
Transmitting means for transmitting the hierarchy information read by the first reading means to a transmission line;
Receiving means for receiving the hierarchy information from the transmission path;
Second storage means for storing the hierarchy information received by the receiving means;
Second readout means for reading out the hierarchy information from the second storage means;
Combining means for combining the hierarchical information stored in the second storage means;
Display means for displaying the synthesized information;
And the scheduled playback time using the available transmission band of the transmission path from the hierarchical information not stored in the second storage means at the time of the second playback to be played after the first playback for the first stream playback A delivery control means for selecting the hierarchical information having an amount of information that can be transmitted before a predetermined time before requesting the first reading means ,
The read request from the distribution control means to the first reading means is hierarchical information that is synthesized and reproduced after the next second reproduction in the second reproduction. Data reproduction system. First accumulation means for accumulating hierarchical information that is information of each hierarchy obtained by hierarchically encoding time-series stream data;
First reading means for reading out the hierarchy information from the first storage means;
Transmitting means for transmitting the hierarchy information read by the first reading means to a transmission line;
Receiving means for receiving the hierarchy information from the transmission path;
Second storage means for storing the hierarchy information received by the receiving means;
Second readout means for reading out the hierarchy information from the second storage means;
Combining means for combining the hierarchical information stored in the second storage means;
Display means for displaying the synthesized information;
And the scheduled playback time using the available transmission band of the transmission path from the hierarchical information not stored in the second storage means at the time of the second playback to be played after the first playback for the first stream playback A delivery control means for selecting the hierarchical information having an amount of information that can be transmitted before a predetermined time before requesting the first reading means,
The read request from the distribution control means to the first reading means is a second request during the period from the time when the first reproduction or the second reproduction is paused until the next time when the second reproduction is requested. It is performed on hierarchical information that is synthesized and reproduced after reproduction.
Stream data playback system. 3. The stream data reproduction system according to claim 2 , wherein the read request to the first reading unit of the distribution control unit is made in order from hierarchical information at a time close to the recording time of the reproduction target for which reproduction has been paused. The read request to the first reading means of the distribution control means is to read the hierarchy information from the recording time shifted by a predetermined time interval from the recording time of the reproduction target paused to the recording time of the reproduction target paused. 3. The stream data reproducing system according to claim 2 , wherein a reading request is sequentially made to one reading means. First accumulation means for accumulating hierarchical information that is information of each hierarchy obtained by hierarchically encoding time-series stream data;
First reading means for reading out the hierarchy information from the first storage means;
Transmitting means for transmitting the hierarchy information read by the first reading means to a transmission line;
Receiving means for receiving the hierarchy information from the transmission path;
Second storage means for storing the hierarchy information received by the receiving means;
Second readout means for reading out the hierarchy information from the second storage means;
Combining means for combining the hierarchical information stored in the second storage means;
Display means for displaying the synthesized information;
And the scheduled playback time using the available transmission band of the transmission path from the hierarchical information not stored in the second storage means at the time of the second playback to be played after the first playback for the first stream playback A delivery control means for selecting the hierarchical information having an amount of information that can be transmitted before a predetermined time before requesting the first reading means,
The read request to the first reading means of the distribution control means is for the hierarchy information at the recording time requested to be paused among the hierarchy information not accumulated in the second accumulation means when the reproduction is paused. It is performed in order from the lower hierarchy
Stream data playback system. The stream data reproduction system according to any one of claims 2 to 5 , wherein the distribution control means stops making a request to read the first reproduction hierarchy information to the first reading means when the reproduction is paused. First accumulation means for accumulating hierarchical information that is information of each hierarchy obtained by hierarchically encoding time-series stream data;
First reading means for reading out the hierarchy information from the first storage means;
Transmitting means for transmitting the hierarchy information read by the first reading means to a transmission line;
Receiving means for receiving the hierarchy information from the transmission path;
Second storage means for storing the hierarchy information received by the receiving means;
Second readout means for reading out the hierarchy information from the second storage means;
Combining means for combining the hierarchical information stored in the second storage means;
Display means for displaying the synthesized information;
And the scheduled playback time using the available transmission band of the transmission path from the hierarchical information not stored in the second storage means at the time of the second playback to be played after the first playback for the first stream playback A delivery control means for selecting the hierarchical information having an amount of information that can be transmitted before a predetermined time before requesting the first reading means,
The distribution control means is constituted only by a receiving device.
Stream data playback system. First accumulation means for accumulating hierarchical information that is information of each hierarchy obtained by hierarchically encoding time-series stream data;
First reading means for reading out the hierarchy information from the first storage means;
Transmitting means for transmitting the hierarchy information read by the first reading means to a transmission line;
Receiving means for receiving the hierarchy information from the transmission path;
Second storage means for storing the hierarchy information received by the receiving means;
Second readout means for reading out the hierarchy information from the second storage means;
Combining means for combining the hierarchical information stored in the second storage means;
Display means for displaying the synthesized information;
And the scheduled playback time using the available transmission band of the transmission path from the hierarchical information not stored in the second storage means at the time of the second playback to be played after the first playback for the first stream playback A delivery control means for selecting the hierarchical information having an amount of information that can be transmitted before a predetermined time before requesting the first reading means,
The distribution control means is provided for each function of a transmitting device and a receiving device.
Stream data playback system.

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