JP3529016B2 - Video playback system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video reproducing system including a client and a server connected via a communication line having a relatively low data transfer rate or a communication line having a packet loss. The present invention relates to a download request method from a server to a client.

[0002]

2. Description of the Related Art Conventionally, in a real-time video reproduction system that transmits video data using a packet network and reproduces it in real time,
When the video data is reproduced in real time, the transmission band of the network is limited, so that the video quality is deteriorated due to the selective packet discard in the server, for example, the motion is reduced due to the reduction of the number of frames, and the coding information of one frame is used. The image quality deteriorates due to the amount reduction, and the image quality deteriorates due to unpredictable packet loss due to the network.

Therefore, in order to reproduce a high quality image on the client side, it was necessary to download a file of image data using a file transfer mechanism and perform local reproduction on the client.

[0004]

In the prior art, when the user performs high-quality video playback of the video during real-time playback on the client side, after the real-time playback is temporarily stopped, the file transfer mechanism is set up. It was necessary to use the server again to obtain the video data file of the video from the server. In this case, the time spent for real-time playback until the user makes a decision to perform high-quality video playback and the file of the relevant video data before the user sees the video by high-quality video playback It takes time to transfer.

Therefore, when the client and the server are connected to each other by a low-speed communication line such as 28.8 Kbps, the time spent for file transfer occupies a large amount of weight, and the user side has high quality. There was a problem that the response time until the video of could be played was lengthened.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to reduce the time spent for downloading video data after real-time reproduction in a video reproduction system. It is an object of the present invention to provide a technology capable of minimizing the time required for a user to reproduce a high-quality image.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[0008]

Among the inventions disclosed in the present application, a brief description will be given to the outline of typical ones.
It is as follows.

That is, the present invention is a video reproducing system which has a server and a client connected via a network, wherein the client reproduces the video data transmitted from the server. Sometimes
Fast forward / rewind / video skip at the client
By the video playback operation of the jump jump playback
In the video reproduction system capable of controlling the video data transmitted from the client, the client stores the video data that has arrived at the client among the video data representing a series of videos, and a storage unit. An image that expresses the series of images
In the data , the video playback operation on the client
Sent from the server to the client under the control of
Not trust, not arrived section parts and non-arrival interval extracting means for extracting, non-arrival interval portion of the video data representing the sequence of image extracted by the non-arrival interval extracting means is a non-arrival to the client And a notification means for notifying the server, wherein the server receives the notification from the client, and transmits the unarrival section part of the video data representing the series of videos to the client. It is characterized by comprising a video data transmitting means.

Also, in the present invention, the server is
A serial number is added to the video data that represents a series of videos.
Send to the client in packets and the client
The non-arrival section extraction means of the
The destination section table and the packet that arrived at the client
Monitor the numbers and extract the section where the packet numbers are continuous
By the continuous section extracting means and the continuous section extracting means
Start packet number and end packet of the obtained continuous section
Arrival section for registering and updating the number in the arrival section table
Table update means and no arrival from the arrival section table
Non-arrival section table creating means for creating section table
It is characterized by having. In the present invention, the
The client uses the video data sent from the server.
Extract the non-arrival part that did not arrive at the client
Further equipped with means for extracting unarrival video data within the arrival section
E, the notifying means is the unarrival video data in the arrival section.
The image transmitted from the server extracted by the extracting means.
Not arrived in the image data that did not arrive at the client
Notify the server of the part as well, and have not arrived within the arrival section
The video data extraction means is a non-arrival packet table within the section.
And a packet of video data that arrived at the client
Number of unarriving packets is monitored and the number of undelivered packets is extracted.
Incoming packet extraction means and the non-arrival packet extraction means
The obtained non-arrival packet number and the continuous section extracting means
And the continuous interval to which the non-arrival packets belong to
The section for registering and updating the unarrival packet table in the section
And an internal non-arrival packet table updating means .

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In all the drawings for explaining the embodiments, parts having the same function are designated by the same reference numerals, and the repeated description thereof will be omitted.

[First Embodiment] FIG. 1 is a block diagram showing a schematic configuration of a video reproducing system according to an embodiment of the present invention.

In the figure, 1 is a server, 2 is a client, 3 is a packet network, 11 is a non-arrival packet extraction mechanism, 12 and 31 are video data representing a series of videos, 1
3 is a remaining packet, 21 is an arrival packet, 22 is a file storage mechanism, 23 is a local file, 24 is a continuous section extraction mechanism, 25 is an arrival section table updating mechanism, 26 is an arrival section table, and 27 is a non-arrival section table creating mechanism. ,
28 is a non-arrival section table, 29 is an acquisition packet, 30
Is a video data restoration mechanism.

In the present embodiment, the real time in which video data is transmitted from the server 1 to the client 2 via the packet network (network) 3 and the video data transmitted from the server 1 in the client 2 is reproduced in real time. It is a video playback system.

FIG. 2 is a diagram showing an example of real-time reproduction on the client 2.

In the example shown in FIG. 2, the user starts reproduction of video data (video content) representing a series of videos, and then fast forwards (JUMP) and restarts (RESU) at time t1.
ME), fast forward (JUMP) and restart (RESUME) at time t2, and rewind (JUM) at time t3.
P), restart (RESUME), pause (PAUSE) at time t4, and restart (RESUM) at time t5.
E), fast forward (JUMP), restart (R) at time t6
ESUME) and fast forward (JUMP) at time t7,
Restart (RESUME) and rewind at time t8 (J
UMP), restart (RESUME), stop (STOP) at time t9, and real-time reproduction is completed.

The processing procedure of the client 2 will be described below with reference to the real-time reproduction example shown in FIG.

The server 1 transmits the video data 12 representing a series of video to the client 2 in a packet with a serial number added, and the client 2 reproduces the video data transmitted from the server 1 in real time. The packet of the video data is stored in the local file 23 using the file storage mechanism 22.

In order to give a serial number to the packets of the video data 12 representing a series of videos in the server 1, the data amount of the video data 12 representing a series of videos and the video data to be transmitted this time are set. The data of which part of the video data 12 representing a series of videos is obtained, and based on this, a serial number is given to the packet of the video data 12 or the video data 1 representing a series of videos in advance.
2 may be divided and stored for each packet unit, and consecutive numbers may be given to the image data 12 expressing the divided series of images.

In the continuous section extraction mechanism 24, the time t at which the JUMP operation is performed by the user's fast forward and rewind operations.
At 1, t2, t3, t6, t7, and t8, the number of the packet arriving from that time is monitored, and the JUMP of the user is monitored.
The skipping of the packets generated by the operation is extracted by the continuity of the packet numbers, and the start packet number and the end packet number of the continuous section are obtained. Further, at the time t9 when the STOP operation is performed by the stop operation by the user, the last packet number arrived from that time is extracted, and the start packet number and the end packet number of the last continuous section are obtained.

In the present embodiment, the continuous section extracting mechanism 24
Thus, the start packet number of the continuous section extracted by the JUMP operation at time t1 is 1, the end packet number is 100, and the start packet number of the continuous section extracted by the JUMP operation at time t2 is 800, the end The packet number is 900, the start packet number of the continuous section extracted by the JUMP operation at time t3 is 950,
The end packet number is 990, the start packet number of the continuous section extracted by the JUMP operation at time t6 is 50, the end packet number is 200, and the JU at time t7
The start packet number of the continuous section extracted by the MP operation is 700, the end packet number is 750, and time t8
, The start packet number of the continuous section extracted by the JUMP operation is 960, and the end packet number is 970,
It is assumed that the start packet number 740 and the end packet number 820 of the continuous section extracted by the STOP operation at time t9 are obtained.

The start packet number and end packet number of the continuous section extracted by the continuous section extraction mechanism 24 are
It is input to the arrival section table updating mechanism 25 and registered or updated in the arrival section table 26.

Specifically, when the input continuous section does not overlap the arrival section registered in the arrival section table 26, it is registered in the arrival section table 26 as a new arrival section, and n If it overlaps the arrival section, it is combined with the overlapping n arrival sections and updated to one arrival section. If the input continuous section falls within a certain arrival section, it is not processed. .

FIG. 3 is a diagram showing the update of the contents of the arrival section table 26 together with the time when the continuous section is input in the present embodiment.

In this embodiment, finally, the first section has a packet number of 1 to 200, the second section has a packet number of 700 to 900, and the third section has a packet number of 950.
To 990, the arrival section table 26 is generated.

In the non-arrival section table creating mechanism 27, the number obtained by adding 1 to the number of the [n] th end packet of the arrival section table 26 created by the arrival section table updating mechanism 25 and the [n + 1] th start packet. The non-arrival section table 28 is created by using the numbers obtained by subtracting 1 from the numbers of 1) as the start packet number and the end packet number of the [n] th non-arrival section table 28, respectively.

The final packet number of the original video data representing a series of videos is set in the [max] th end packet of the non-arrival interval table 28 which is the final non-arrival interval.

FIG. 4 shows the contents of the arrival section table 26 and the non-arrival section table 2 finally created in this embodiment.
8 shows the contents.

In the present embodiment, the number of the last packet of the video data representing a series of videos on the server 1 is 1.
000.

The client 2 uses the non-arrival section table 2
8 information is notified to the server 1. The server 1 obtains the number information of the non-arrival packet from the information of the non-arrival section table 28 transmitted from the client 2, and uses the non-arrival packet extraction mechanism 11 to leave the non-arrival packet from the video data 12 concerned. The packet 13 is extracted and the remaining packet 13 is transmitted to the client 2.

The client 2 has a video data restoration mechanism 3
The acquisition packet 29 transmitted from the server 1 by using 0
And the packets stored in the local file 23 are combined in the order of packet numbers to restore original video data representing a series of videos.

As described above, according to the present embodiment, the longer it takes for real-time reproduction on the client 2 to decide to perform high-quality video reproduction of the video, the longer the conventional video data. It is possible to shorten the time when high-quality video reproduction is started after real-time reproduction, as compared with the download method using the file transfer mechanism.

For example, if the file size of video data is X
[Byte], the transmission speed of the network 3 between the client 2 and the server 1 is set to N [byte per sec], and it is determined whether the user downloads the video data for high-quality video reproduction (local reproduction). In the conventional example, as shown in FIG. 6, when Tw [sec] is set as the time taken by the user to decide whether or not to download, when the process is performed during real-time reproduction (browsing) on the network, The time required to download the video data using the file transfer mechanism becomes X / N [sec], and it takes (Tw + X / N) [sec] until the high quality video reproduction is provided.

However, in this embodiment, as shown in FIG. 5, video data is immediately provided to the user via the network 3 by real-time reproduction. Therefore, if the time it takes for the user to decide whether or not to download is Tw [sec], the file size of the video data acquired during this time is N * Tw [byte], and the remaining files (X-N * Since the time required to acquire Tw) [byte] is (X−N * Tw) / N [sec], the time required for the user to perform high-quality video reproduction of video data is X / N [ sec], which makes it possible to shorten Tw [sec] compared to the conventional example.

As described above, in this embodiment, the time until it is decided to perform high-quality video reproduction of a series of video,
In other words, the longer the real-time reproduction time in the client 2, the more effective it is than the conventional download method using the video data file transfer mechanism.

[Second Embodiment] FIG. 7 is a block diagram showing a schematic structure of a video reproducing system according to another embodiment of the present invention.

The present embodiment is a real-time video reproduction system in which video data representing a series of videos is transmitted from the server 1 to the client 2 via the Internet and the client 2 reproduces the video in real time.

Further, the present embodiment is the same as the first embodiment.
In the video data that has already arrived at the client 2,
This is an example of the case where there is a packet loss, and the unarrival packet extraction mechanism 32 is provided to the client 2 side of the first embodiment.
The intra-section non-arrival packet table updating mechanism 33 and the intra-section non-arrival packet table 34 are added.

Like the first embodiment, the client 2
Then, during the real-time reproduction of the video data transmitted from the server 1, the packet of the video data is transferred to the file storage mechanism 2
2 in the local file 23.

The processing procedure of the client 2 will be described below with reference to the real-time reproduction example shown in FIG.

As in the case of the first embodiment, the continuous section extracting mechanism 24 extracts the start packet number 1 and the end packet number 100 of the continuous section extracted by the JUMP operation at the time t1 at the time t2. Of the start packet of the continuous section extracted by the JUMP operation of
0, end packet number 900, JUM at time t3
The start packet number of the continuous section extracted by the P operation is 950, the end packet number is 990, the start packet number of the continuous section extracted by the JUMP operation at time t6 is 50, and the end packet number is 200, The start packet number of the continuous section extracted by the JUMP operation at time t7 is 700, and the end packet number is 75.
0, the start packet number of the continuous section extracted by the JUMP operation at time t8 is 960, the end packet number is 970, and the start packet number of the continuous section extracted by the STOP operation at time t9 is 740, the end It is assumed that the packet number is 820.

Further, the packet number is 10, 2 in the continuous section [1-100] extracted by the JUMP operation at the time t1 by the unarrival packet extraction mechanism 32.
Packets that are 0, 60, 80 and JUM at time t2
Continuous section extracted by P operation [800-900]
Inside, the packets whose packet numbers are 810, 815 and 890 and the packets whose packet numbers are 955, 965 and 975 in the continuous section [950-990] extracted by the JUMP operation at time t3. , Time t6
The continuous section [50- extracted by the JUMP operation at
200], the packet numbers are 60 and 70, and the packet number is 7 in the continuous section [700-750] extracted by the JUMP operation at time t7.
Packets 10, 745 and STOP at time t9
In the continuous section [740-820] extracted by the operation, the packet numbers are 760, 805, 810, 815.
It is assumed that the non-arrival of a packet is extracted.

In-section unarrival packet table updating mechanism 3
In 3, the unarrival packets belonging to the arrival segment managed by the arrival segment table 26 are unarrival packets within the segment,
An intra-arrival packet table 34 managed by an intra-arrival packet sub-table corresponding to the arrival segment, and further including an intra-arrival packet sub-table corresponding to each arrival segment in the arrival segment table 26
Is managed.

Specifically, depending on the continuous section to which the non-arrival packets extracted by the continuous section extraction mechanism 24 belong, overlapping n arrival sections and n corresponding non-arrival packet sub-tables in the section Is required.

The number of unarrival packets extracted by the unarrival packet extraction mechanism 32 and the n number of unarrival packet sub-tables corresponding to the arrival segment that overlaps the continuous segment to which the unarrival packet belongs are registered. The comparison with the number of the packet that has not arrived within the section is performed as follows.

Regarding the overlapping section, if the number of the unarriving packet is already registered in the unarriving packet sub-table within the section, it is judged that it has not arrived even within the continuous section, and the section of the number of the packet concerned. Not deleted from the sub-arrival packet sub-table, and if the number of the non-arrival packet is not registered in the sub-arrival packet sub-table, it is judged that it has arrived in the past It is not registered in the packet sub table.

Further, if the number of the arrival packet extracted this time is already registered in the intra-section non-arrival packet sub-table, it is judged that the packet arrives in the continuous section this time, and the section corresponding to the number of the packet concerned. Delete from the unarrival packet sub table.

Further, the n non-arrival packet sub-tables that overlap the continuous segment extracted by the continuous segment extraction mechanism 24 are integrated into one non-arrival packet sub-table. For the non-overlapping sections, the number of the non-arrival packet is registered in the new section non-arrival packet sub-table.

FIG. 8 is a diagram showing updating of the contents of the intra-section unarrival packet table 34 of this embodiment.

In the present embodiment, finally, the intra-section non-arrival packet table 34 is composed of three intra-section non-arrival packet sub-tables. In the intra-section non-arrival packet table 34, the packet numbers 10, 20, 60 are included. , 710,
760, 810, 815, 890, 955, 965, 9
The packet that is 75 is registered.

FIG. 9 is a diagram showing the contents of the non-arrival section table 28 and the intra-section unarrival packet table 34 that are finally created according to this embodiment.

In the present embodiment, the number of the last packet of the video data representing a series of videos on the server 1 is 1.
000.

The client 2 notifies the server 1 of the information of the non-arrival section table 28 and the information of the intra-section unarrival packet table 34 as in the first embodiment. The server 1 obtains the number information of the non-arrival packet from the information of the non-arrival segment table 28 and the intra-segment non-arrival packet table transmitted from the client 2, and uses the non-arrival packet extraction mechanism 11 to perform a series of operations. A non-arrival packet is extracted from the video data 12 representing a video as a residual packet 13, and the residual packet 13 is transmitted to the client 2.

The client 2 uses the video data restoration mechanism 3
The acquisition packet 29 transmitted from the server 1 by using 0
And the packets stored in the local file 23 are combined in the order of packet numbers to restore original video data representing a series of videos.

As described above, the invention made by the present inventor is
Although the specific description has been given based on the above-described embodiment, the present invention is not limited to the above-described embodiment, and needless to say, various modifications can be made without departing from the scope of the invention.

[0057]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

(1) According to the present invention, by performing real-time playback on the client, when performing high-quality video playback of a series of videos, it is possible to shorten the time spent for downloading after determining high-quality video playback. Therefore, the longer it takes to determine high-quality video playback, the shorter the time from real-time playback to the start of high-quality video playback compared to the conventional download method that uses a file transfer mechanism for video data. It becomes possible to do.

(2) According to the present invention, since the range designation is used to specify the packet in the non-arrival section instead of using the packet number of each packet, the number of request parameters to the server can be reduced. It will be possible.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a video reproduction system according to an embodiment of the present invention.

FIG. 2 is a diagram showing an example of real-time reproduction on a client.

FIG. 3 is a diagram showing updating of contents of an arrival section table together with a time when a continuous section is input in the first embodiment.

FIG. 4 is a diagram showing the contents of an arrival section table and a non-arrival section table finally created in the first embodiment.

FIG. 5 is a diagram for explaining a time required to start high-quality video playback of the series of videos by real-time playback on the client in the first embodiment.

FIG. 6 is a diagram for explaining a time until a high-quality video reproduction of the series of videos is started by real-time reproduction on a client in a conventional example.

FIG. 7 is a block diagram showing a schematic configuration of a video reproducing system according to another embodiment of the present invention.

FIG. 8 is a diagram showing updating of the contents of an intra-section non-arrival packet table in the second embodiment.

FIG. 9 is a diagram showing the contents of a non-arrival section table and the intra-section non-arrival packet table finally created in the second embodiment.

[Explanation of symbols]

1 ... Server, 2 ... Client, 3 ... Packet network, 11
... Unarrival packet extraction mechanism, 12, 31 ... Video data,
13 ... Remaining packet, 21 ... Arrival packet, 22 ... File storage mechanism, 23 ... Local file, 24 ... Continuous section extraction mechanism, 25 ... Arrival section table updating mechanism, 26 ...
Arrival section table, 27 ... Non-arrival section table creating mechanism, 28 ... Non-arrival section table, 29 ... Acquisition packet,
30 ... Video data restoration mechanism, 32 ... Unarrival packet extraction mechanism, 33 ... In-section unarrival packet table updating mechanism,
34 ... In-arrival packet table within a section.

Continuation of the front page (56) References JP-A-4-156193 (JP, A) International Publication 97/004585 (WO, A1) Fukunaga, Matsumura, Nakai, error resilience video coding system adapted to transmission channel conditions, Image Encoding Symposium 11th Symposium Materials (PCSJ96), Japan, October 7, 1996, p. 67-68 (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04N 7/10 H04N ^7/ 16-7/173 H04N ^7/ 24-7/68 JISST file (JOIS)

Claims (3)

(57) [Claims] And a 1. A server and a client connected via a network, with the client, a video reproducing system for reproducing video data transmitted from the server, in the client during the video data playback Fast forward
Replay, rewind, video skip, jump video playback
Video data transmitted from the server can be controlled by operation
In the effective video reproduction system , the client stores the video data that has arrived at the client among the video data representing a series of video, and the video data representing the series of video, The server is controlled by the video playback operation on the client.
Server which is not transmitted from the server to the client and which has not yet arrived at the client, the non-arrival section extraction means, and the video data representing the series of videos extracted by the non-arrival section extraction means. And a notification means for notifying the server of a non-arrival section in the server, the server receiving a notification from the client,
A video reproduction system comprising a non-arrival video data transmission means for transmitting a non-arrival section part of the video data representing the series of videos to the client. 2. The server sends video data representing the series of videos to the client in a packet to which a serial number is added, and the unarrival section extraction means of the client includes an arrival section table and an unarrival section. A section table, a continuous section extracting unit that monitors the number of packets that have arrived at the client and extracts a section in which the packet numbers are continuous, and the start packet number and end of the continuous section obtained by the continuous section extracting unit and arrival section table updating means for registering updated to the arrival interval table number of the packet, according to claim 1, characterized in that it comprises a non-arrival section table generating means for generating a non-arrival section table from the arrival interval table Video playback system. 3. The client sends from the server.
If the received video data does not reach the client
Unarrival video data in the arrival section to extract the unarrival part
Extraction means is further provided, and the notification means extracts unarrival video data in the arrival section.
Image data transmitted from the server extracted by the means.
Part of the data that did not arrive at the client
Also, the notify the server, before Kiita deposition section in not arrived video data extracting means, a non-arrival packet table section monitors the number of packets of video data arrives at the client's non-arrival packet Using the non-arrival packet extraction means for extracting the number, the non-arrival packet number obtained by the non-arrival packet extraction means, and the continuous section to which the non-arrival packet obtained by the continuous section extraction means belongs, 3. The video reproduction system according to claim 2 , further comprising: intra-section non-arrival packet table updating means for registering and updating the non-arrival packet table.