JPH0937212A - Moving image reproduction system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reproduce a moving image whose reproduction frame rate is increased by adopting the configuration that a frame is rewound to reproduce an image from a new reproduction start point. SOLUTION: A client device 200 calculates a moving image frame number at a rewinding start point from a moving image frame number at a the time when there is a moving image rewinding reproduction request and send this number to a moving image server 100 together with the moving image rewinding and reproduction request. The image server 100 retrieves the moving image data and decides a reproduction frame rate according to a transmission speed of a transmission line 310 between the moving image server 100 and the client device 200, interleaves frames at a rate of 1/n sequentially from a designated reproduction start moving image frame to send moving image data. When storage moving image data for a rewinding part stored in a storage section (memory) 270 are in existence, the client device 200 rearranges image data in the order of faces from the synthesis of the read moving image data and the received moving image data, and decodes the resulting frames at a double reproduction frame rate to display a moving image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving picture reproducing system composed of a moving picture server and a client device which are connected via a transmission line such as Ethernet having a transmission speed which is insufficient for transmitting moving picture data. The present invention relates to a technique effective when applied to a moving image reproduction system with a special reproduction function, which enables continuous reproduction after moving back to a certain time when reproducing a moving image.

[0002]

2. Description of the Related Art Special reproduction functions in a moving image reproduction system include a moving image stop, fast forward and rewind function, and a skip search function at the time of fast forward and rewind. Regarding rewinding, a method is known in which a client device instructs a rewinding point to a moving image server, and the moving image server performs reproduction at that point as a new reproduction starting point. In the video playback system having the rewinding function by this method, the user traces back to a certain time by sending a rewinding request instructing the rewinding point to the server due to reasons such as missing of the video during playback. You can watch the video again from that point.

[0003]

SUMMARY OF THE INVENTION As a result of studying the above prior art, the present inventor has found the following problems.

In the conventional moving picture reproducing system having the rewinding function, the moving picture which is rewound and reproduced from a new reproduction start point is a moving picture under the same condition as the previously reproduced one.
If only video data that does not have a sufficient playback frame rate can be sent due to restrictions on the transmission speed of the transmission path, there is a problem that the user cannot check the video as well as before despite the replay. .

It is an object of the present invention to provide a moving picture reproducing system capable of reproducing a moving picture with an increased reproduction frame rate by rewinding and reproducing from a new reproduction starting point.

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.

[0007]

The outline of a typical invention among the inventions disclosed in the present application will be briefly described as follows.

(1) In response to a moving image reproduction request from a client device, a moving image server transmits moving image data, the transmitted moving image data is received by the client device, and the received moving image data is decoded and displayed. In the system, means for transmitting first moving image data having a number of frames according to the speed of the transmission path from the moving image data stored in the moving image server, and first moving image data transmitted from the moving image server. Means for receiving the received first moving image data, means for decoding the received first moving image data, and means for storing the received first moving image data while updating it in a storage unit (memory) in frame order. When the user of the client device issues a rewinding reproduction request, the moving picture server moves from the reproduction point to the second moving picture different from the first moving picture data. A unit for transmitting moving image data, the client device receiving the transmitted second moving image data, reading the first moving image data from the storage unit (memory), and the first moving image data and the first moving image data. Means for combining and reproducing the second moving image data.

(2) The frame of the second moving image data is a frame which is an intermediate point between two consecutive received frames of the frame of the first moving image data.

(3) In the rewind reproduction request, a is a frame number when the rewind reproduction request is generated, b is a reproduction frame rate when the moving image server is stored, 1 / n is a frame thinning rate, and the user of the client device Rewind time required (nx
-N / 2) The moving picture frame number of the rewinding start point is obtained by a-nx + n / 2 with the positive integer value closest to 1 / b as the value of x, together with the moving picture frame number of the rewinding start point. send.

According to the above-mentioned means, the moving image server transmits the moving image data in which the number of frames of the accumulated moving image data is reduced according to the speed of the transmission path, and the client device receives the moving image data received from the moving image server. When the video data is decrypted and stored in the memory in frame order while being updated to a certain amount at all times, and the user of the client device makes a request to go back to a certain time when playing the video and then continuously play the video data, the video server Video data of a frame different from the already transmitted frame is transmitted from the reproduction point, the client device receives the data, at the same time reads the video data accumulated in the memory, and reproduces both video data in combination. As a result, the transmission speed of the transmission line connecting the video server and the client device is sufficient for the playback frame rate. If the user of the client device has difficulty in following the instantaneous change of the moving image in normal reproduction due to insufficient transmission of the moving image data that the user has, the user can rewind and then reproduce the moving image. The playback frame rate of can be doubled, and a moving image with better quality than normal playback can be viewed.

[0012]

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

FIG. 1 is a block diagram showing a schematic configuration of an embodiment of a moving image reproducing system of the present invention. In FIG. 1, 100 is a video server, 110 is a video server control unit, 120 is a video server video storage unit, 130 is a video server playback frame rate determination unit, 140 is a video server frame decomposition unit, and 150 is a video server. Network input / output section of
Reference numeral 200 is a client device, 210 is a control unit of the client device, 220 is an input unit of the client device, 230
Is a frame determination unit of the client device, 240 is a display unit of the client device, 250 is a decoding unit of the client device, 260 is a frame assembly unit of the client device, 27
Reference numeral 0 is a storage unit of the client device, 280 is a reception buffer unit of the client device, 290 is a network input / output unit of the client device, and 310 is a transmission line.

As shown in FIG. 1, the moving image reproducing system of this embodiment has a moving image server 100 and a client device 20.
0 is connected by a transmission line 310.

The video server 100 includes a video server control unit 110, a video server video storage unit 120, a video server playback frame rate determination unit 130, a video server frame decomposition unit 140, and a video server network input / output unit. 15
It consists of zero.

The client device 200 includes a control unit 210 of the client device and an input unit 2 of the client device.
20, a frame determination unit 230 of the client device, a display unit 240 of the client device, a decoding unit 250 of the client device, a frame assembly unit 260 of the client device,
The client device includes a storage unit 270, a client device reception buffer unit 280, and a client device network input / output unit 290.

FIG. 2 is a flow chart when the user of the client device of the embodiment of the moving picture reproducing system of the present invention sends a moving picture normal reproduction request to the moving picture server to display a moving picture, and FIG. 3 is a moving picture reproduction of the present invention. 7 is a flowchart in the case where the user of the client device of the embodiment of the system sends a moving image rewinding reproduction request to the moving image server and displays a moving image.

The operation of the moving image reproducing system of this embodiment will be described below.

The operation client device 200 is shown in FIG.
As shown in, the user's request is accepted via the input unit 220, and the request is sent to the video server 100 via the control unit 210 and the network input / output unit 290. In the case of a moving image rewinding reproduction request, the frame determination unit 230 similarly requests the moving image server 100 after obtaining the start frame number.

The moving picture server 100 includes a network input / output unit 15
0, according to the request received through the control unit 110, the moving image storage unit 120 is searched for moving image data. Next, the reproduction frame rate determination unit 130 determines the reproduction frame rate according to the transmission speed of the transmission line 310, and the frame decomposition unit 140 stores 1 / n frames of the moving image data that actually stores the moving image data. Make it a number. The moving image data with the reduced number of frames is sent to the operation client device 200 through the network input / output unit 150.

The operation client device 200 receives the moving image data through the network input / output unit 290 and the reception buffer unit 280. In the case of normal playback of a moving image, the reception buffer unit 2
The moving image data read from 80 is decoded by the decoding unit 250 and displayed on the display unit 240.

The moving image data read from the reception buffer unit 280 is stored in the storage unit 270 while being updated in a frame order up to a fixed amount.

In the case of moving picture rewinding reproduction, the moving picture data read from the receiving buffer section 280 and the moving picture data read from the accumulating section 270 are rearranged in frame order by the frame assembling section 260 to double the reproduction frame rate. Then, the decoding unit 250 decodes the data and the display unit 240 displays it.
When all the moving image data of the rewinding portion is read from the storage unit 270, the operation at the normal reproduction is started.

Next, with reference to the flow chart of FIG. 2, a procedure for normally reproducing a moving image in the embodiment of the moving image reproducing system of the present invention will be described.

The user of the client device 200 specifies a reproduction moving image and makes a normal reproduction request for the moving image by the moving image server 100.
To (S201). The moving image server 100 searches for the requested moving image data (S202), and determines the reproduction frame rate according to the transmission speed of the transmission line 310 connecting the moving image server 100 and the client device 200 (S20).
3), moving image frames are sequentially thinned at a ratio of 1 / n (where n is an even number), and moving image data is transmitted (S204). The client device 200 receives the video data (S20
5) Then, the moving image is displayed by decoding in frame order (S206) (S208). On the other hand, the received moving image data is stored in the storage unit (memory) 270 while being updated in a frame order up to a fixed amount (S207).

FIG. 4 shows the rewinding time in the embodiment of the moving picture reproducing system of the present invention, which is the moving picture frame number from the moving picture rewinding time and the moving picture frame number at the time of requesting the rewinding reproduction of the moving picture. FIG. 4 is a diagram for explaining a method of calculating a number, where a is a frame number when a rewind reproduction request is generated, b is a reproduction frame rate (fps) when the moving image server is accumulated, and 1 / n (where n is an even number) is The frame thinning rate, x is a positive integer value. The blank part (□ part) is the reception frame before the rewind reproduction request, and the black part (□ part) is the reception frame after the rewind reproduction request.

Next, the procedure for rewinding and reproducing a moving image in the embodiment of the moving image reproducing system of the present invention will be described with reference to the flowchart of FIG.

When the user of the client device 200 specifies a rewind time during normal reproduction of a moving image and issues a rewinding reproduction request of the moving image (S301), the client device 200 is executed.
Calculates the rewind time from the rewind time of the moving picture and the moving picture frame number at the time when the rewind reproduction request of the moving picture is issued (S302). The client device 200 sends this video frame number to the video server 100 together with a video rewinding reproduction request. The video server 100 searches for the requested video data (S30
3), the reproduction frame rate is determined according to the transmission speed of the transmission line 310 that connects the video server 100 and the client device 200 (S304), and the client device 200 is determined.
From the reproduction start moving image frame designated by, the frames are thinned out at a rate of 1 / n and the moving image data is transmitted (S30).
5). The client device 200 receives the moving image data (S306), determines whether there is accumulated moving image data of the rewind portion accumulated in the accumulation unit (memory) 270, and accumulates it in the accumulation unit (memory) 270. If there is accumulated moving image data for the rewinding portion, the accumulation unit (memory) 2
The moving image data stored in 70 is read out (S3
08), the read moving image data and the received moving image data are combined and rearranged in frame order (S309), and decoded at a double reproduction frame rate (S309).
310), a moving image is displayed (S311).

All the stored moving image data stored in the storage unit (memory) 270 of the rewinding portion is read out (S
(No 307), the operation at the time of normal reproduction is started, only the received moving image data is returned to the original reproduction frame rate and decoded in frame order (S310), and the moving image is displayed (S310).
Simultaneously with 311), the received moving image data is accumulated in the memory while being updated to a certain amount in frame order (S312).

As the calculation method in step S302, as shown in FIG. 4, when the moving picture frame number at the time of requesting the rewinding reproduction of the moving picture is a, the moving picture frame number at the rewinding start point is (a-nx + n). / 2) (where x is a positive integer). This means that (a-nx) represents the moving picture frame number received by x before, and by adding n / 2, the moving picture frame which is just the midpoint between two consecutive received frames. This is because the number can be obtained.

Therefore, assuming that the reproduction frame rate of the moving image data stored in the moving image server is b, (nx-n / 2) 1 / b representing the rewinding time is the rewinding required by the user of the client device. The value of (a-nx + n / 2) is obtained from the value of x when the time is closest to the time, and this is set as the moving image frame number of the rewinding start point.

As an example, FIG. 5 shows a case where n = 4 and x = 3.
Shown in In FIG. 5, a circle indicates a reception frame before a rewind reproduction request, a triangle indicates a reception frame after a rewind reproduction request, and RT indicates a rewind time. In the rewind time RT, the number of frame intervals during this period is (4 × 3-4 / 2), and one frame interval time is 1 / b (s), so (4 × 3-4 /).
2) × 1 / b (s) = 10 / b (s).

As can be seen from the above description, according to the embodiment of the moving picture reproducing system of the present invention, the moving picture server 1
00 and the client device 200 are connected by a transmission line 310 such as Ethernet, and the transmission speed is insufficient for transmitting moving image data having a sufficient reproduction frame rate, and the user of the client device 200 is normally reproduced. Is difficult to follow the instantaneous changes in the video,
The user can double the reproduction frame rate of the moving image by rewinding and then reproducing the moving image, and can see a moving image of better quality than normal reproduction.

As described above, the inventions made by the present inventor are
Although the present invention has been specifically described based on the above-mentioned embodiments, the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the scope of the invention.

[0035]

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

The moving image server and the client device are connected by a transmission line such as Ethernet, and the transmission speed is insufficient for transmitting moving image data having a sufficient reproduction frame rate, and the client device is used for normal reproduction. When it is difficult for the person to follow the instantaneous change of the video,
The user can double the reproduction frame rate of the moving image by rewinding and then reproducing the moving image, and can see a moving image of better quality than normal reproduction.

[Brief description of drawings]

FIG. 1 is a block configuration diagram showing a schematic configuration of an embodiment of a moving image reproduction system of the present invention.

FIG. 2 is a flowchart showing a procedure of a moving image normal reproduction operation in the moving image reproduction system of the present embodiment.

FIG. 3 is a flowchart showing a procedure of a moving image rewinding reproducing operation in the moving image reproducing system of the present embodiment.

FIG. 4 is a diagram for explaining a method of calculating a rewinding start point in the moving image reproduction system of this embodiment.

FIG. 5 is a diagram for explaining an example of a method of calculating a rewind start point in the moving image reproduction system of this embodiment.

[Explanation of symbols]

100 ... video server, 110 ... control part of video server, 1
20 ... Video storage unit of video server, 130 ... Playback frame rate determination unit of video server, 140 ... Frame decomposition unit of video server, 150 ... Network input / output unit of video server, 200
... client device, 210 ... client device control unit, 220 ... client device input unit, 230 ... client device frame determination unit, 240 ... client device display unit, 250 ... client device decoding unit, 2
Reference numeral 60 ... Client device frame assembly unit, 270 ... Client device storage unit, 280 ... Client device reception buffer unit, 290 ... Client device network input / output unit, 310 ... Transmission path

Claims (3)

[Claims] 1. A moving picture reproducing system in which a moving picture server transmits moving picture data in response to a moving picture reproduction request from a client apparatus, the transmitted moving picture data is received by the client apparatus, and the received moving picture data is decoded and displayed. In the above, in the moving picture data stored in the moving picture server, a means for transmitting first moving picture data composed of the number of frames according to the speed of the transmission path, and the first moving picture data transmitted from the moving picture server Means for receiving at the client device, means for decoding the received first moving image data, and means for storing the received first moving image data while updating it in a storage unit (memory) in frame order. When the user of the client device issues a rewind reproduction request, the moving picture server causes a second moving picture different from the first moving picture data from the reproduction point. A means for transmitting data, the client device receiving the transmitted second moving image data, reading the first moving image data from the storage unit (memory), and reading the first moving image data and the first moving image data. 2. A moving picture reproducing system, characterized in that the moving picture reproducing system is provided with a means for reproducing the combined moving picture data. 2. The frame according to claim 1, wherein the frame of the second moving image data is a frame that is an intermediate point between two consecutive received frames of the frame of the first moving image data. Video playback system. 3. The rewind reproduction request is requested by the user of the client device, a is a frame number when the rewind reproduction request is generated, b is a reproduction frame rate when the moving image server is stored, 1 / n is a frame thinning rate. Rewind time (nx-n
/ 2) Using a positive integer value closest to 1 / b as the value of x, obtain the moving picture frame number of the rewinding start point by a-nx + n / 2, and send it together with the moving picture frame number of the rewinding start point. The moving image reproduction system according to claim 1 or 2.