JP2003158731A - Image delivery system, camera terminal, and receiving terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable images which are minuter than initially delivered images to be provided without increasing a bit volume steadily when the delivered images are re-sent. SOLUTION: Image signals A obtained through a camera 11 of a camera terminal 10 are encoded through both an encoder 12a at a high compression rate to generate a low-quality image bit stream BL which is fed to a switch 14 and an encoder 12b at a low compression rate to generate a high-quality image bit stream BH which is fed as a delayed high-quality image bit stream BH' to the switch 14 through the intermediary of a recording medium 13. Usually, the low-quality image bit stream BL is delivered to receiving terminals 20 through a network 30. When the images which are delivered already are requested to be resent from the receiving terminal 20, the switch 14 is switched by a system controller 23 to deliver the high-quality image bit stream BH' obtained through the recording medium 13 to the receiving terminal 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video distribution system including a camera device for distributing captured video information to a network and a receiver for displaying video information obtained from the network, a camera terminal, and a receiving terminal.

[0002]

2. Description of the Related Art Conventionally, there is known a system such as a surveillance camera system which receives video information obtained from a plurality of cameras via a network and displays it on a display screen of a receiver. With the development of video information compression technology and the speeding up of network infrastructure, it has become possible to construct a video distribution system using the camera section of such a system as a broadcasting station and the screen display section as a terminal of each home. .

FIG. 15 is a block diagram showing a conventional example of such a video distribution system, in which 10 is a camera terminal,
11 is a camera, 12 is an encoder, 20 is a receiving terminal, 2
1 is a decoder, 22 is a display, 23 is a system controller, 24 is a changeover switch, 25 is a recording medium (recording / reproducing apparatus), and 30 is a network.

In the figure, in this conventional video distribution system, a camera terminal 10 and a receiving terminal 20 are connected via a network 30. The camera terminal 10 has a camera 11 and an encoder 12, and the receiving terminal 20 has a decoder 21, a display 22, a system controller 23, a changeover switch 24, and a recording medium 25.

Next, the operation of this conventional example will be described.

In the camera terminal 10, the camera 11 takes a picture and generates a video signal. This video signal is subjected to information compression processing by the encoder 12 to generate a bit stream, and this bit stream is supplied to the receiving terminal 20 via the network 30. As described above, the camera terminal 10 is a minimum unit for delivering a bitstream, and one or more camera terminals 10 are connected to the network 30 to deliver a bitstream from each.

In the receiving terminal 20, the system controller 23 controls each part. Under this control, the bit stream from the predetermined camera terminal 10 transmitted via the network 30 is selected and decoded by the decoder 21 into a video signal. The decoded video signal is recorded and stored in the recording medium 25, and is also supplied to the display 22 by the system controller 23 via the changeover switch 24 closed to the a-contact side, where the video display is performed.

When the viewer of the receiving terminal 20 wants to watch the distributed video again, the viewer performs a predetermined operation for that purpose, and the system controller 23 switches the changeover switch 24 to the b contact side. The recording medium 25 is operated to read out the video signal and supplied to the display 22 via the changeover switch 24. As a result, the past video signal stored in the recording medium 25 can be reproduced on the display 22.

[0009]

In the above-mentioned conventional example, the viewer needs the rewinding reproduction because the image displayed on the display 22 draws attention. Because I want to see the video of in detail. To this end, the camera terminal 10
It is necessary to deliver detailed video from. But,
For this purpose, it is necessary to reduce the compression rate and increase the bit amount on the encoder 12 side.

By the way, in the video distribution system typified by the surveillance camera system, it is necessary to constantly distribute the video.
A large number of camera terminals 10 are connected and a bit stream of video signals from them is always transmitted. Therefore, when the bit amount of the bit stream output by each camera terminal 10 is increased, the bit amount transmitted by the network 30 increases according to the number of camera terminals 10 connected thereto.

On the other hand, the network 30 also has a transferable capacity, and the transferable bit amount is limited. Therefore, if a detailed (high-quality) video bit stream compressed at a low compression rate is constantly transmitted from each camera terminal 10 via the network 30, the camera terminals 10 connected to the network 30 will naturally be connected. If the number of camera terminals 10 is limited and the number of camera terminals 10 is to be connected to the same network 30, the compression rate of the video signal in each camera terminal 10 must be increased, and attention should be monitored. It cannot be viewed again with high-quality images.

The present invention has been made in view of such a problem, and an object thereof is to obtain a high quality image of the same portion to be viewed again without constantly increasing the transmission bit amount in the network. It is to provide a video distribution system, a camera terminal, and a receiving terminal capable of performing the above.

[0013]

To achieve the above object, according to the present invention, a camera terminal and a receiving terminal are connected via a network, and a bit stream generated from a video image captured by the camera terminal is distributed to the receiving terminal. In the video distribution system, the camera terminal encodes a captured video signal to generate a first bitstream and a second bitstream forming a video image with higher image quality than the first bitstream. Then, the first bit stream is usually delivered to the receiving terminal, and in response to the resending request from the receiving terminal, the second bit stream from the video which is a predetermined time before the time when the resending request is made is delivered. It is configured to do.

Further, the present invention is also a video distribution system, wherein the network is an upper layer network connecting the camera terminal and the local server, and a lower layer network connecting the local server and the receiving terminal. The camera terminal has a hierarchical structure including a hierarchical network, and the camera terminal encodes the picked-up video signal to form a first bitstream and a second bitstream that forms a video of higher image quality than the first bitstream. And a bit stream is generated, and the first and second bit streams are simultaneously transmitted to the upper layer network, and the receiving terminal receives either of the first and second bit streams from the local server via the lower layer network. Is selectively delivered.

Furthermore, the present invention is a video distribution system in which a plurality of camera terminals are connected to a receiving terminal via a network, and a bit stream generated from video taken by these camera terminals is distributed to the receiving terminal. Camera terminal encodes a captured video signal to generate a first bitstream and a second bitstream forming a video of higher image quality than the first bitstream. The first bit stream generated by the camera terminal is simultaneously delivered to the receiving terminal,
When one of the plurality of camera terminals is designated by the receiving terminal and a resend request is made, only the designated camera terminal delivers the second bit stream to the receiving terminal.

Furthermore, the present invention is a video distribution system in which a camera terminal and a receiving terminal are connected via a network, and a bit stream generated from a video image taken by the camera terminal is distributed to the receiving terminal. N bitstreams (where n is an integer of 3 or more) encoded by different processing methods according to the playback mode of the video at the receiving terminal are generated, and specified by the request from the receiving terminal that specifies the playback mode. The bit stream corresponding to the reproduced mode is distributed to the receiving terminal.

In order to achieve the above-mentioned object, the present invention is a camera terminal for delivering video information via a network, and a camera for outputting a video signal of a photographed subject,
A first encoder that encodes this video signal to generate a first bitstream, and a second encoder that encodes this video signal to generate a second bitstream of a higher image quality than the first bitstream. And a recording medium for recording and reproducing the second bit stream, and the first and second bit streams are used as video information for distribution.

The present invention is also a camera terminal, which outputs a video signal of a photographed subject, and a first encoding process and a second encoding process of this video signal in a time-division manner. And a recording medium that records and reproduces the second bitstream, and a processor that generates the second bitstream of the second bitstream and a second bitstream of a video having a higher image quality than the first bitstream. The second bit stream is used as video information to be distributed.

Furthermore, the present invention is also a camera terminal, which outputs a video signal of a photographed subject,
From this video signal, a video portion within the extraction range set for each frame is extracted, and the output video signal of the signal processing portion and the signal processing portion for expanding the extracted video portion to the entire one frame are encoded. A first encoder that generates a first bitstream, and a second encoder that encodes a video signal output from a camera and generates a second bitstream of a video having a higher image quality than the first bitstream. And a recording medium for recording and reproducing the second bit stream, and the first and second bit streams serve as video information to be distributed.

Further, the present invention is also a camera terminal, which outputs a video signal of a photographed subject,
A first encoder that encodes this video signal to generate a first bitstream, and a second encoder that encodes this video signal to generate a second bitstream of a higher image quality than the first bitstream. A second encoder, and an image / voice recognition circuit for performing at least one of image recognition based on this video signal output from the camera and voice recognition based on a voice signal output from a microphone provided in the camera, A recording medium for recording and reproducing the second bit stream based on the recognition result of the image / speech recognition circuit is provided, and the video information for distributing the first and second bit streams is provided.

Furthermore, the present invention is also a camera terminal, which outputs a video signal of a photographed subject,
The video signals are encoded by different processing methods to generate bit streams of different image quality n
The number of encoders (where n is an integer of 3 or more) and a recording medium for recording and reproducing bit streams other than the bit stream of the lowest image quality are provided as video information for distributing these n bit streams. It is a thing.

Further, in the above camera terminal, a changeover switch for selecting and distributing any one of the generated bitstreams is provided, and the changeover switch is controlled to be switched in response to a request from a distribution destination. It is what

In order to achieve the above object, the present invention is a receiving terminal for receiving a video bit stream distributed via a network, and a decoder for decoding the received bit stream into a video signal, and a decoder for decoding the video signal. In addition, a configuration is provided that includes a display that is supplied with this video signal and displays the video, and a system controller that requests retransmission of the video displayed on the display to the video distributor as a high-quality video. .

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a first embodiment of a video distribution system, a camera terminal and a receiving terminal according to the present invention, in which 10 is a camera terminal, 11 is a camera, and 1 is a camera.
Reference numerals 2a and 12b are encoders, 13 is a recording medium (or a recording / reproducing device; however, in the following description, a recording medium will be described, but it may be a recording / reproducing device), 14 is a changeover switch, 20 is a receiving terminal, and 21 is A decoder, 22 is a display, 23 is a system controller, and 30 is a network.

In the figure, the camera terminal 10 and the receiving terminal 20 are connected via a network 30 to form a video distribution system. Here, one camera terminal 10 and one receiving terminal 20 are shown, but two or more camera terminals 10 and receiving terminals 20 are provided in the network 30.
May be connected to. The camera terminal 10 is the camera 11
The receiving terminal 20 includes a decoder 21a and an encoder 12a, a selector switch 14, and a recording medium 13.
It has a system controller 23 and a display 22.

Next, the operation of the first embodiment will be described.

In the camera terminal 10, the camera 11 shoots and generates the video signal A. This video signal A
Is encoded by the encoder 12a at a high compression rate, for example, based on an international standard MPEG (Moving Picture Expert Group) compliant method, etc.
A low bit rate, and thus a low quality bit stream (hereinafter referred to as the low quality bit stream) _BL is generated. Further, the video signal A generated by the camera 11 is information-compressed by the encoder 12b based on a low compression rate, for example, a method based on MPEG, and a high bit rate, and accordingly, a high quality bit stream (hereinafter _BH ) is generated. The changeover switch 14 is the system controller 23 of the receiving terminal 20.
Switching control is performed by, but it is normally closed to the a contact side. Therefore, the low image quality bit stream B _L output from the normal encoder 12a is passed through the changeover switch 14,
It is transmitted on the network 30.

The high quality bit stream B _H output from the encoder 12b is constantly supplied to the recording medium 13 and recorded therein. The recording medium 13 is, for example, a semiconductor memory and is capable of recording and reproducing at the same time. That is, the high-quality bit stream B _H supplied from the encoder 12b is sequentially recorded, and the portion recorded before the recording time by a predetermined time T is reproduced. Therefore, the high quality bit stream B _H is reproduced from the recording medium 13 with a delay of a predetermined time T. Reproduction high quality bit stream B from recording medium 13
_H'is supplied to the b contact of the changeover switch 14, but since the normal changeover switch 14 is closed to the a contact side, this reproduced high quality image bit stream B _H'is not supplied to the network 30.

When the recording medium 13 is a semiconductor memory, recording is performed from the head address, but when recording for a predetermined time T is made, it means that recording for the recording capacity is made. Recording will be performed again from the head address, and the contents already recorded will be rewritten. Also, the reproduction is performed with a delay of a predetermined time T from this recording. In this way, the recording and the reproduction are simultaneously performed, so that the high-quality bit stream which is always recorded and delayed by the predetermined time T is reproduced. In this case, the recording medium 13 may be a memory having a capacity capable of recording the high image quality bit stream for a time slightly longer than the predetermined time T. This predetermined time T
Can be arbitrarily set as appropriate, but when this embodiment is applied to a surveillance camera system, a time period in which a high-quality image can be seen from a scene that goes back some time before the scene that calls attention Need to This also applies to other embodiments described later.

Further, the bit streams B _L and B _H are MPE
When encoded in a G-compliant system, the delivery of the high-quality bit stream B _H ′ for the retransmission request is intra-frame encoded and starts from the frame or immediately before that.

In this way, the video signal A output from the camera 11 is converted into the low image quality bit stream _BL .
It is distributed from the network 30 to the receiving terminal 20.

The receiving terminal 20 receives the bit stream distributed via the network 30, and the decoder 21 decodes the bit stream into the original video signal and displays it on the display 2.
2 is supplied. As a result, the distributed video is displayed on the display 22.

When a scene that draws the viewer's attention is displayed in such a display state and the viewer wants to see this scene again,
When the viewer performs a predetermined operation (hereinafter, referred to as a resend operation) with the remote controller or the operation unit on the receiving terminal 20 side,
The system controller 23 generates the switching control signal C,
It is transmitted to the camera terminal 10 via the network 30.
In the camera terminal 10 that has received this, the changeover switch 14 is controlled by this changeover control signal C, and the contact point a to b
Switch to contact. As a result, the reproduced high quality bit stream B _H ′ of the recording medium 13 is distributed (retransmitted) to the receiving terminal 20 via the changeover switch 14 and the network 30. As a result, this reproduced high quality bit stream B _H '
Is decoded into a high quality video signal by the decoder 21 and supplied to the display 22 to display a high quality video.

Here, the reproduced high image quality bit stream B _H 'of the recording medium 13 is a bit stream delayed from the low image quality bit stream B _L output from the encoder 12a and distributed by the above predetermined time T. Therefore, the display 22 of the receiving terminal 20 starts to display a high-quality image from a time point that is a predetermined time T backward from the current time point. That is, the same effect as the rewinding reproduction from the recording / reproducing apparatus can be obtained with a high-quality image, which allows the above-mentioned scene of the viewer's attention to be seen again with a high image quality. . At this time, since the changeover switch 14 is switched to the b contact side, the low image quality bit stream _BL from the encoder 12a is not transmitted through the network 30.

When the bit stream B _H ′ is delivered to the receiving terminal 20 for a certain set time T ′ which is equal to or longer than the above-mentioned predetermined time T, the changeover switch 14 is automatically switched to the a contact side, so that the low image quality is obtained. The distribution of the bit stream B _L may be returned to, or as long as the receiving terminal 20 does not request the distribution of the low image quality bit stream B _L (that is, unless the switching control signal is transmitted from the system controller 23), it remains high. The image quality bit stream B _H ′ may be continuously distributed.

When an image by the low image quality bit stream B _L is displayed and a scene (scene) that calls attention is displayed, the normal viewer views the scene once and then re-views this scene. I want to see it. In such a case, the camera terminal is requested to resend after seeing this scene. In response to such a retransmission request, in any of the above cases, the display of the high-quality video by the retransmitted high-quality bit stream B _H 'must start from at least the beginning of at least one of the above scenes. Instead, the above-mentioned predetermined time T must be set to be equal to or longer than the time to go back to the beginning of this scene.
For example, if the viewer recognizes that he or she has seen such a scene, the predetermined time T may be set longer than the time.

In the above case, the display period of the high quality image by the high quality bit stream B _H ′ (the set time T ′) can be appropriately set to an arbitrary time normally requested by the viewer. Also, in the above case, the viewer can continue to view high-quality video until he is satisfied.

The above also applies to the embodiments described later.

[0039] Figure 2 is a timing diagram illustrating the above operations, the (a) shows the timing of the low quality bitstream B _L and quality bitstream B _L in the camera terminal 10, FIG. (B ) Indicates the display timing of the low image quality video by the low image quality bit stream B _L and the display timing of the high image quality video by the high image quality bit stream B _H at the receiving terminal 20.

In the figure, when the time when the receiving terminal 20 is operated to receive the distribution from the camera terminal 10 is t ₁ , the receiving terminal 20 receives the low image quality stream B _L and the decoder 21 converts it into a video signal. Decoded, time t
_The low-quality image starts to be displayed on the display 22 from ₂ . After that, there is a scene where the viewer is alerted at time t ′ in this video, and when the viewer performs an operation for playing back high-quality video at time t ₃ in order to see it again, the system controller 23 A switching control signal is sent from the camera terminal 10 to the camera terminal 10 via the network 30.
Then, the changeover switch 14 is switched to the b contact side, the high-quality bit stream B _H recorded from the recording medium 13 from time t ₁ is reproduced, and is delivered to the receiving terminal 20 via the changeover switch 14 and the network 30. It In the receiving terminal 20, this bitstream of image quality B _H is decoded by the decoder 21 into a high quality video signal, and the high quality video signal from time t ₁ is supplied to the display 22 from time t ₄ to perform video reproduction. Be done.

The portion output from the encoder 12b at time t ₁ and recorded on the recording medium 13 is reproduced from the recording medium 13 with a delay of the above-mentioned predetermined time T from this. Therefore, the quality bitstream B _H shown in FIG. 2 there is shown a high-quality bit stream B _H output from the encoder 12b, part of that time t _1, this than a predetermined time T delay It is delivered to the receiving terminal 20.

The time t ₁₂ (= t ₂ −t ₁ ) until the display of the time t ₁ portion of the low image quality bit stream B _{L on} the display 22 is the high image quality bit stream B _L.
It is low that the time t ₁ of _H is longer than the time t ₃₄ (= t ₄ −t ₃ ) from the start of distribution (time t ₃ ) to the start of display on the display 22 (time t ₄ ). This is because the image quality bit stream B _L has more information compression, and therefore it takes time to decode the original video signal.

As described above, according to the first embodiment, the camera terminal 10 delivers high-quality video only when the viewer is alerted to the delivered video and wants to review it again. . In normal times, the low image quality bit stream B _L having the minimum necessary image quality bit rate is transmitted, and only when the system controller 23 requests it, the high image quality bit stream B _H is transmitted, so that the network 30 can be constantly operated. It becomes possible to reduce the amount of bits to be transmitted. Further, when the high image quality bit stream B _H is retransmitted, it becomes possible to obtain a detailed (that is, high image quality) video signal as compared with the conventional technique shown in FIG.

In the first embodiment, for simplification of description, the number of camera terminals connected to the network 30 is one, but the number of camera terminals is increased within the range in which the network 30 can transmit a bit stream, and reception is performed. A plurality of screens may be viewed on the terminal. For example, for the purpose of monitoring with a large number of cameras, normally, a large number of camera terminals are connected and the image quality output by each camera terminal is reduced to suppress the bit rate transmitted by the network 30. However, when an abnormality occurs that draws the viewer's attention, the low-quality bitstreams of other camera terminals are suppressed or eliminated, and only the video of the focused camera terminal is delivered as a high-quality bitstream, and this is received by the receiving terminal. It will be possible to view in detail again. Normally,
Since the minimum necessary low image quality bit rate is sufficient, it is possible to increase the number of camera terminals without changing the maximum transmission capacity of the network 30, and when an abnormality occurs, limit the camera terminals to those that generate more than that. By viewing it after that, it is possible to obtain a detailed video.

In addition, for example, when the first embodiment is intended for television broadcasting, the amount of data that can be transmitted through the network 30 per unit time is finite, so that the broadcasting station is dependent on the amount of viewed data. , No charge or C
It is envisaged to insert M. The viewer can watch the television broadcast efficiently by normally watching the low-quality bit stream and requesting the high-quality bit stream as needed at the time of watching.

In the above description, the high-quality image reproduced from the recording medium 13 and distributed is the display 2
Although it can be seen only once in 2, the receiving terminal 20 is provided with the recording medium 22 and the changeover switch 24 controlled by the system controller 23 as in the conventional receiving terminal 20 shown in FIG. While displaying the decoded high quality video signal on the display 22,
It is also possible to record on the recording medium 22, reproduce the high-quality video signal from the recording medium 22 when necessary, and supply it to the display 22 via the changeover switch 24. This also applies to other embodiments described later.

Although the recording medium 13 in FIG. 1 is a semiconductor memory, it may be a recording medium such as a recordable / reproducible disk or magnetic tape. In this case, when the switching control signal C is supplied from the system controller 23, the recording medium is also controlled to switch from the recording mode to the reproduction mode, and the recording is performed a predetermined time T before the switching time. The reproduction of the high quality bit stream B _H is started from. This also applies to other embodiments described later.

FIG. 3 is a block diagram showing a second embodiment of a video distribution system, a camera terminal and a receiving terminal according to the present invention. 10a and 10b are camera terminals and 20a and 2 are shown.
0b and 20c are receiving terminals, 30 to 32 are networks,
Reference numerals 40 and 41 denote local servers, and parts corresponding to those in FIG.

In the figure, in this embodiment, the network 30 is hierarchically configured with the network 30 as the upper layer and the networks 31 and 32 as the lower layer. The network 30 is a high-capacity network of the upper layer. . The plurality of camera terminals 10a and 10b are connected to the plurality of local servers 40 and 41 via the network 30 of the upper layer. The lower layer network 31 connects between the local server 40 and the receiving terminal 20a, and the lower layer network 32 connects between the local server 41 and the receiving terminals 20b and 20c.

The camera terminals 10a and 10b are different from the camera terminal 10 in FIG. 1 only in that the changeover switch 14 is not provided, and therefore,
Each of the camera terminals 10a and 10b has an encoder 12
The low image quality bit stream B _L output from the recording medium 13 and the high image quality bit stream B _H ′ delayed by the recording medium 13 are constantly transmitted via the network 30 to the local servers 40 and 41.
Send to. Therefore, in the local servers 40 and 41,
The low image quality bit stream and the delayed high image quality bit stream from all the camera terminals connected to the network 30 are stored.

On the other hand, the receiving terminal 20a connected to the local server 31 and the receiving terminals 20b and 20c connected to the local server 32 have the same configuration as the receiving terminal 20 shown in FIG. Normally, the low quality bit stream is distributed from the local servers 40 and 41 via the networks 31 and 32, but the display 2
There is a scene that draws the viewer's attention by watching the video of the low-quality bit stream displayed in 2, and when the viewer performs a predetermined operation to request the resending of the scene, the system controller 23 resends the scene. The request signal is formed, output, and transmitted to the local servers 40 and 41 via the networks 31 and 32. When the local servers 40 and 41 receive this retransmission request signal,
Instead of the low image quality bit stream, the delayed high image quality bit stream corresponding to the low image quality bit stream that has been transmitted so far is delivered to the receiving terminal 20a or the receiving terminals 20b, 20c via the networks 31 and 32.

In this way, the upper layer network 30
Then, the low-quality bit stream _BL from each camera terminal
And the high image quality bit stream B _H ′ are simultaneously transmitted, but in the lower layer networks 31 and 32, only one of the low image quality bit stream B _L and the high image quality bit stream B _H ′ is transmitted.

In this way, each of the receiving terminals 20a ...
In 20c, when a resend request is issued, the scene that calls attention can be seen again in high-quality images, and the local servers 40 and 41 have the same camera terminal 10a, respectively.
Since the low image quality bit stream from 10b and the delayed high image quality bit stream are stored, if the respective receiving terminals 20a to 20c can acquire the images from these camera terminals 10a and 10b, the same is true. Images from the camera terminal 10a or 10b can be simultaneously acquired.

As described above, in the second embodiment, as in the first embodiment shown in FIG.
When a low bit rate low quality bit stream is transmitted and the viewer views the same video again, the high bit rate high quality bit stream is retransmitted.
It is possible to obtain high-quality images.

Further, even if all the receiving terminals make a request for resending the high image quality bit stream to one camera terminal, the camera terminal only needs to transmit this request to each local server. The maximum transmission capacity per hour is not exceeded.

Further, for example, when the second embodiment is intended for television broadcasting, it is expected that viewers concentrate on one camera terminal and request a high image quality bit stream. Hierarchical network 30
And the lower layer networks 31 and 32 are hierarchized, the transmission load on the recording medium 13 in the camera terminal can be reduced and the high quality bit stream can be continuously transmitted to the receiving terminal. .

FIG. 4 is a block diagram showing a third embodiment of a video distribution system, a camera terminal and a receiving terminal according to the present invention, in which 15 is a processor, 16 is a memory, and 16a.
Is an encode program, and 16b is an encode program. The portions corresponding to those in FIG.

In the figure, the processor 15 includes an encoding program 16 a, 1 stored in the memory 16.
By executing 6b, the video signal A output from the camera terminal 10 is encoded. Here, the encoding program 16a causes the processor 15 to perform the same processing as that of the encoder 12a in FIG.
The encoding program 16b is the encoder 1 in FIG.
The processor 15 performs the same processing as 2b. As a result, the processor 15 generates the low image quality bit stream B _L and the high image quality bit stream B _H , the low image quality bit stream B _L is supplied to the changeover switch 14, and the high image quality bit stream B _H is recorded on the recording medium 13.
Will be supplied to and recorded.

FIG. 5 is a timing chart showing a specific example of the processing operation of the processor 15 in FIG. 4, where the horizontal axis is the time axis and the time ta + tb is one frame period of the camera 11.

The processor 15 executes the encoding programs 16a and 16b in a time-division manner every time period (one frame period) in which the camera 11 outputs the video signal A of one frame (FIG. 4). The encoding program 16a is executed in the period ta before the one frame period to generate the low image quality bit stream B _L , and the encoding program 16b is executed in the period tb after the same frame period to generate the high image quality bit stream B _H. .

Here, the processor 15 is provided with a frame memory, and the video signal A supplied from the camera 11 is temporarily stored in the frame memory, and is first read from this frame memory at high speed to obtain the encoding program 1.
6a performs the encoding process within the period ta to generate the low image quality bit stream B _L , and then is read again from this frame memory at a high speed, and the encoding program 16b performs the encoding process within the period tb to obtain the high quality bit stream B _L. A quality bitstream B _H is generated. The generated low image quality bit stream B _L and high image quality bit stream B _H are once recorded in different frame memories, read out from them so as to have a time length of one frame period, and output from the processor 15. It

In this way, in the third embodiment, the processor 15 performs the encoding process in a time-division manner, thereby performing the encoding process with a different compression rate without increasing the number of parts constituting the camera terminal 10. In addition, the high quality bit stream can be retransmitted in response to a request from the receiving terminal 20. Further, by reducing the number of parts, it is possible to reduce the weight of the camera terminal 10 and the number of manufacturing processes.

Needless to say, the third embodiment can be applied to the second embodiment shown in FIG.

Next, a fourth embodiment of the video distribution system, the camera terminal and the receiving terminal according to the present invention will be described. The configuration of the fourth embodiment is the same as that of the previous embodiment, but the configuration of the first embodiment shown in FIG. 1 will be described below.

In FIG. 1, the fourth embodiment also enables retransmission of a still image from the recording device 13. Therefore, the encoder 12b performs reversible compression (for example, intraframe coding) of the video signal A from the camera 11 for each frame.

When the viewer performs a resend operation on the receiving terminal 20 side, the changeover switch 14 in the camera terminal 10 is changed by the changeover control signal from the system controller 23, as in the first embodiment shown in FIG. Switching to the contact point b side, the high quality bit stream B _H ′ is retransmitted from the recording medium 13 to the receiving terminal 20 and a high quality image is displayed on the display 22, but when the viewer gives an instruction operation to reproduce a still image, The instruction control signal is the system controller 23.
Is supplied to the camera terminal 10, the recording medium 13 is controlled, and the one frame high-quality image bit stream at that time is repeatedly read and delivered to the receiving terminal 20. As a result, a still image is displayed on the display 22 of the receiving terminal 20 by repeating the high-quality bit stream of one frame.

Alternatively, the receiving terminal 20 is provided with a recording medium 25 as shown in FIG. 15 or a recording medium such as a frame memory and a changeover switch 24, and the high quality bit stream B _H ′ is also provided on this recording medium. The one frame high-quality image bit stream recorded at this time may be repeatedly reproduced from the recording medium and supplied to the display 22 together with the above-described instruction to reproduce the still image.

By the way, in the video compression method typified by the MPEG method, inter-frame coding by motion compensation is performed in most frames because the correlation between the frames before and after the video signal is high. A frame subjected to inter-frame coding by motion compensation generally has lower image quality than a frame subjected to intra-frame coding in order to improve a compression rate. For this reason, if a pause is performed at a frame that has been subjected to inter-frame coding by motion compensation and a still image is requested, an image with poor image quality is stopped and displayed on the display 22.

However, in the fourth embodiment, the high-quality bit stream is subjected to reversible compression processing, so that the viewer does not receive the distributed high-quality image even when it is temporarily displayed. Since the decoder 21 at 20 decodes the high-quality bit stream B _H 'into a video signal while maintaining high image quality, a high-quality still image without deterioration in image quality can be obtained.

Next, a fifth embodiment of the video distribution system, the camera terminal and the receiving terminal according to the present invention will be described. The configuration of the fifth embodiment is the same as that of the previous embodiment, but a high-quality slow motion image (hereinafter referred to as a slow image) is also obtained. The configuration shown in FIG. Will be described as an example.

The operation of the fifth embodiment will be described below with reference to FIG. 6. FIG. 6A shows a frame encoded by the encoder 12a in FIG. 1, and FIG. Each of the frames subjected to the encoding process by the encoder 12b in FIG. 3C shows the frame of the video displayed on the display 22 in the receiving terminal 20.

The encoder 12a in FIG.
As shown in (a), the frame 1,
A low image quality bit stream B _L is output frame by frame in the order of frame 2, frame 3, ...

Further, as shown in FIG. 6B, the encoder 12b encodes a high frame rate video signal received from the camera so that a slow image is also possible. Here, in FIG. 6B, a frame 1.5 is a frame at an intermediate time between frames 1 and 2, and a frame 2.5 is a frame at an intermediate time between frames 2 and 3. The same applies hereinafter. Here, each frame 1, frame 1.5, frame 2, frame 2.5, ... Is a frame that is time-compressed to 1/2 frame time length so that a double slow image can be obtained. Is a high quality bit stream B _H of
This is output from the encoder 12b and recorded on the recording medium 13.

In general, in order to obtain n (where n is an integer of 2 or more) slow images, (n-
1) Frames whose contents sequentially change from one frame to the other frame are inserted.

From the recording medium 13, the high quality image bit stream B _H 'of each frame is reproduced at the frame cycle.
The receiving terminal 20 can request the reproduction of the slow image (double slow image in the case of the high image quality bit stream _BH of FIG. 6B) as well as the normal image as the retransmission from the recording medium 13. .

Therefore, as shown in FIG. 6C,
When the low-quality bit stream B _L shown in FIG. _6A is distributed and displayed as an image on the display 22 in the “(1) normal reproduction” state, when a slow reproduction request is made on the receiving terminal 20 side, As described above, the changeover switch 14 is b
It switched to the contact side, and FIG. 6 (b) image quality each frame as shown has been recorded on the recording medium 13 by 1/2 frame period in the bit stream B _L high-quality bitstream B _H of each frame period of one frame And is retransmitted from the changeover switch 14 to the receiving terminal 20 via the network 30. Thus, the display 22, as shown in FIG. 6 (c), the frame is frame 0 of 1 frame time length from the time _ts. 5 frame 1, frame _1.5, frame 2, it is displayed in the order of ...... This means that "(2) Slow playback" with double high-quality slow playback
It becomes a state.

The receiving terminal 20 can also request retransmission of a normal high-quality bit stream. In this case, in response to this request, the high quality bit stream of every other frame is read from the recording medium 13 in the order of frame 1, frame 2, frame 3, ...
It is delivered to the receiving terminal 20.

As described above, in the fifth embodiment,
Only when slow reproduction is selected for the distributed image, it is possible to increase the frame rate and observe the video. It is when the video changes quickly that the viewer needs slow playback. Since the encoder 12b always encodes at a high frame rate, it is not seen from the output from the encoder 12a (between frames 0.5, frame 1..d shown as d, e, f in FIG. 6C). 5, it is possible to see the movement of the frame 2.5) in detail, and it is possible to observe the detailed movement.

In the fifth embodiment, the recording medium 1 is used as the high quality bit stream B _H ′ for slow reproduction.
Although the inter-frame insertion is performed between the frames of the input video signal A before the recording of the high quality bit from the encoder 12, the high quality bits from the encoder 12b are processed in the same manner as the first embodiment shown in FIG. When the stream B _H is recorded on the recording medium 13 and reproduced from the recording medium 13, the high-quality slow reproduction may be performed by repeatedly reproducing the high-quality bit stream of each frame a plurality of times.

Next, a sixth embodiment of the video distribution system, the camera terminal and the receiving terminal according to the present invention will be described. In the sixth embodiment, a plurality of camera terminals are simultaneously delivered, and these delivered images can be simultaneously displayed on the display of the same receiving terminal. FIG. 7 is a block diagram for explaining the sixth embodiment when images are simultaneously delivered from two camera terminals to the same receiving terminal.
Is a camera terminal having the same configuration as the camera terminal 10 in the previous embodiment, but here, it is assumed that the camera terminal 10 has the same configuration as that of the camera terminal 10 shown in FIG. And redundant description will be omitted.

In the figure, from the receiving terminal 20, a changeover control signal C from the system controller 23 of the receiving terminal 20 causes the changeover switches 14a, 14b of the camera terminals 10a, 10b.
14b can be controlled, and the system controller 23 can control a receiving unit (not shown) of the receiving terminal 20. As a result, the receiving terminal 20 can receive an image (a low-quality image or a high-quality image) delivered from one of the camera terminals 10a and 10b, and display the received image on the display 22. However, it is also possible to receive video images from both of the camera terminals 10a and 10b at the same time and display these video images on the display 22 at the same time.

FIG. 8 is a timing chart showing the operation of the sixth embodiment. FIG. 8A shows the timing of the low image quality bit stream B _L and the image quality bit stream B _H at the camera terminal 10a. 1B shows the camera terminal 10
The timings of the low image quality bit stream B _L and the high image quality bit stream B _{H in} b are shown respectively, and FIG. 11C shows the display timing of the low image quality video by the low image quality bit stream B _{L in} the display 22 of the receiving terminal 20. And the display timing of a high quality image by the high quality bit stream B _H.

In the figure, when a viewer simultaneously operates the camera terminals 10a and 10b on the receiving terminal 20 side to request video distribution (time t1), the camera terminals 10a and 10b are operated.
The low image quality bit streams _BL from a and 10b are simultaneously received, and these are simultaneously supplied to the display 22 which has been decoded into a video signal by the decoder 21. At this time, a processing unit (not shown) performs a screen reduction process on these video signals, whereby the display 2
2, the camera terminal 10a, as shown in FIG.
Thumbnail display in which the images 1 and 2 from 10b are reduced and simultaneously displayed is performed (time t2).

After that, for example, there is a scene where the image from the camera terminal 10b calls attention to the viewer, and when the viewer performs an operation requesting retransmission of the high-quality image 2 (time, t3), the system controller 23
Causes a receiving unit (not shown) to receive only the bit stream from the camera terminal 10b, and closes the changeover switch 14 in the camera terminal 10b to the b contact side by the changeover control signal C. Thereby, the camera terminal 10b
The high-quality bit stream B _H 'is distributed from and is received by the receiving terminal 20, which is decoded and displayed on the display 2.
2 is supplied. At this time, that is, when only the bit stream distributed from one camera terminal is received, the system controller 23 controls FIG.
As shown in (b), the received image (in this case, a high quality image from the camera terminal 10b) is displayed on the display 2
2 is displayed on the entire screen (time t4).

Although two camera terminals are targeted here, the same is true when an arbitrary number of camera terminals of three or more is targeted.

As described above, in the sixth embodiment, after the viewer previews the images of a plurality of camera terminals,
It is possible to view the image of the desired camera terminal from the beginning again.

Further, when the sixth embodiment is applied to television broadcasting, if the capacity of the recording medium 13 is set to a predetermined time T, the viewer can simultaneously watch the beginning portion of the program broadcast at the same time. If a program that is interesting is selected within this predetermined time T, it will be possible to watch it from the start of the broadcast. In this case, in the recording medium 13, this program is recorded from the head address as the program starts to be broadcast, but when a program for a predetermined time T is recorded, it means that the recording capacity is recorded. Recording will be performed again from the head address, and the contents already recorded will be rewritten. Also, the receiving terminal 20
When there is a read request from the recording medium 13 from the system controller 23, the reading of the recording medium 13 is started from the head address. As a result, if the system controller 23 of the receiving terminal 20 issues a read request from the recording medium 13 within a predetermined time T from the start of receiving the program, the program is read from the beginning and received. It will be delivered to the terminal 20. Therefore, the predetermined time T is as shown in FIG.
The thumbnail shown in (a) may be for a time such that the viewer can sufficiently select a desired program from a plurality of programs that are always displayed, for example, for one to several minutes.

In this way, the viewer can select the program after actually watching the program, and the EPG (Elector)
The program can be selected easily and efficiently as compared with program guides such as onic Program Guide).

FIG. 10 is a block diagram showing a seventh embodiment of a video distribution system, a camera terminal and a receiving terminal according to the present invention, in which 17 is a signal processing section, and the same symbols are given to the portions corresponding to FIG. And redundant description will be omitted.

In the figure, the camera terminal 10 is provided with a signal processing unit 17, and after the video signal A output from the camera 11 is processed by this signal processing unit 17,
The low quality bit stream B _L is generated by being supplied to the encoder 12a and encoded. Other than this, the configuration is the same as that of the first embodiment shown in FIG. 1. Therefore, the encoder 12b encodes the video signal A from the camera 11 as it is to generate a high quality bit stream B _H.

The signal processing unit 17 extracts a part of the video signal A output from the camera 11 so as to extract a part of the video image captured by the camera 11, and sets the extracted part as the size of one screen. Enlargement processing is performed so that
to be supplied to a.

This will be explained with reference to FIG. 11. In FIG. 11A, the range 50 is the photographing range of the camera 11, and the video signal A of this photographing range 50 is output from the camera 11. The signal processing unit 17 extracts a part of a range (hereinafter referred to as an extraction range) 51 of the shooting range 50 from the video signal A in the shooting range, and the extraction range 51
Is expanded so that it is displayed on the entire screen of the display 22 of the receiving terminal 20. In this expansion processing, line interpolation processing is performed so that one frame line corresponds to the number of lines of the video signal A.

In this way, the photographing range 5 of the camera 11
A video signal A ′ obtained by expanding the video of a part of the extraction range 51 of 0 is output from the signal processing unit 17, and is supplied to the encoder 12a to be encoded. Here, for example, the extraction range 51 is set to 1 / several times of the imaging range 50 to 1/1.
The video signal A ′ is a video signal whose band is sufficiently narrowed as compared with the original video signal A by setting it to about 0 times, and therefore the encoder 12a encodes the original video signal A. It is possible to encode at a higher information compression rate than the above.

When the low image quality bit stream B _L output from the encoder 12a is supplied from the changeover switch 14 to the receiving terminal 20 via the network 30, the display 22 displays the same as shown in FIG. 11
The image of the extraction range 51 shown in (a) is enlarged and displayed over the entire screen.

Here, in FIG. 11A, the extraction range 51 is, for each frame, as shown by the arrow, the shooting range 5
The position is changed so that it moves in zero. For this reason,
The image displayed on the display 22 also changes. When an image, such as a person 52, that draws attention to the viewer enters the extraction range 51, the display 22 also displays the person 52 as shown in FIG. Image begins to appear. Looking at this to some extent, if the viewer makes a request operation for resending on the receiving terminal 20 side,
Similar to the first embodiment shown in FIG. 1, the changeover switch 1
4 is closed to the b contact side and the high quality bit stream B _H 'is distributed from the recording medium 13 and is displayed on the display 22 as shown in FIG.
A high quality image of the shooting range 50 shown in (a) is displayed.

As described above, in the seventh embodiment, normally, the limited area within the photographing range of the camera is viewed, and the entire screen is viewed as needed. It is also possible to display an image in which an image requiring retransmission can be recognized while significantly reducing the amount of received bits.
In addition, since only a limited area (video of the extraction range 51) is delivered in normal times, the amount of bits constantly transmitted by the network 30 can be significantly reduced.

Next, an eighth embodiment of the video distribution system, the camera terminal and the receiving terminal according to the present invention will be described with reference to FIG. The configuration of this eighth embodiment is also shown in FIG.
It is similar to the first embodiment shown in FIG.

FIG. 12A shows the resolution of the video obtained from the bit stream _BL output from the encoder 12a in FIG. 1, and FIG. 12B shows the bit stream B output from the encoder 12b in FIG. _It shows the resolution of the image obtained from _H. 12
The grid surrounded by the dotted lines in (a) and (b) represents pixels.

As is apparent from FIGS. 12 (a) and 12 (b), the video of the bit stream B _L output from the encoder 12a has a resolution sufficient for viewing it, but the encoder 12b The bit stream B _H output from the recording medium 13 and thus the video from the bit stream B _H 'reproduced from the recording medium 13 is encoded by the encoder 12a.
The video has a higher resolution than the video by the bit stream B _L output from. For this reason, it is sufficient for the viewer to normally watch the video based on the bit stream _BL from the encoder 12a.

[0100] A scene that calls attention while viewing a video by the bit stream B _L appears, and when the viewer requests the resending, similar to the previous embodiment, the recording medium 13
The bit stream B _H ′ is reproduced from and is delivered to the receiving terminal 20, and a high-resolution image is displayed on the display 22. The details of the part that attracted attention by this video,
For example, when this portion is the face portion of the person 53, the facial expression can be clearly recognized because the number of pixels of this face portion is large.

Further, in the eighth embodiment, when the high resolution video is retransmitted in this way, the video signal decoded by the decoder 21 in the receiving terminal 20 is displayed on the display 22 via the frame memory. It is possible to magnify and display the part of the user's attention.

Now, there is a scene to call attention to the viewer in the image display state shown in FIG. 12 (a), and when the viewer requests resending in response to this, as described above, the camera terminal 1
The bit stream B _H ′ of the high resolution video reproduced from the recording medium 13 at 0 is distributed to the receiving terminal 20, decoded by the decoder 21 and supplied to the display 22 via the frame memory. As a result, a high-resolution image as shown in FIG. 12B is displayed on the display 22. Here, if a predetermined portion is designated by a cursor operation or the like on this high-resolution image screen, this designated portion is displayed. An area having a predetermined size is enlarged and displayed by the read control of the frame memory. This enlarged display area is displayed so as to overlap the image shown in FIG. 12B, for example.

Here, attention is paid by setting the enlargement ratio of the image in the enlarged display area to a value such that the resolution of the image in the enlarged display area is equal to or lower than the resolution of the image shown in FIG. 12A. The image can be enlarged and displayed with sufficient resolution. Therefore, even if a part of the image is enlarged and displayed, a clear image can be obtained, and the viewer can clearly recognize the part of the image to be confirmed.

FIG. 13 is a block diagram showing a ninth embodiment of a video distribution system, a camera terminal and a receiving terminal according to the present invention, in which 18 is an image / voice recognition circuit, and FIG.
The same reference numerals are given to the portions corresponding to, and redundant description will be omitted.

In the figure, the camera terminal 11 is provided with an image / speech recognition circuit 18, and a specific image from the image signal obtained from the camera 11 or, alternatively, an illustration provided on the camera 11. When a specific sound is detected by the image / speech recognition circuit 18 from the sound signal output from the microphone, the image / speech recognition circuit 18 controls the recording medium 13 in response to the detection, and a high sound from the encoder 12b is output. The image quality bit stream B _H is written in the recording medium 13.

Here, the specific image is, for example, an image of a moving object, and when this embodiment is applied to the surveillance system, when a person or the like enters the shooting scene, this image / image is displayed. The voice recognition circuit 18 recognizes this,
While recognizing this, the recording medium 13 is controlled to record the high quality bit stream B _H from the encoder 12b. Further, some specific videos are stored in the image / speech recognition circuit 18, and when a video other than the stored specific videos is recognized from the video signal A from the camera 11, or this specific video is recognized. The recording medium 13 may be caused to perform a recording operation when the image is recognized. The same applies to voice, and when voice is output from the above microphone, the image / voice recognition circuit 18 may recognize the voice and cause the recording medium 13 to perform a recording operation, or some specific voices. The patterns are stored, and when the voice of a pattern other than these specific voice patterns is output from the microphone, or when these specific voice patterns are output from the microphone, the image / voice recognition circuit 1
8 may recognize this and start the recording operation of the recording medium 13.

As described above, in the ninth embodiment, since the recording medium 13 is written according to the recognition result of the image / voice recognition circuit 18, the storage capacity required by the recording medium 13 can be reduced. In addition, a long-time image can be stored in the recording medium 13.

The information stored in the recording medium 13 in this way is controlled by the control signal from the system controller 23.
It is read and delivered to the receiving terminal 20. Therefore, the viewer obtains the information stored in the recording medium 13 and requests the display 2 by making a distribution request when necessary.
2 can be displayed.

FIG. 14 is a block diagram showing a tenth embodiment of a video distribution system, a camera terminal and a receiving terminal according to the present invention, in which 12c is an encoder and 13a is a recording medium. Are denoted by the same reference numerals and redundant description will be omitted.

In the figure, this tenth embodiment is
The encoder 12c is different from the first embodiment shown in FIG.
And a recording medium 13a are added, and the changeover switch 14 selects either one of the output of the encoder 12a and the output of the recording medium 13, 13a.

That is, as a method of displaying an image (a mode of image reproduction) on the display 22 of the receiving terminal 20, as described above, not only normal reproduction of a low-quality image or high-quality image (normal display) is performed. Various modes such as slow playback, slow playback, still image playback, and high-speed playback are conceivable. In order to make these possible, a bitstream to be distributed is encoded by a processing method suitable for the mode of image playback. Must have been done (eg, as above,
When reproducing a still image from a bitstream encoded by a processing method conforming to MPEG, good still image reproduction is not always performed). In this sixth embodiment, from this, a bit stream encoded by various processing methods can be obtained.

The encoder 12c is the encoder 12a, 1
2b performs an encoding process different from that of 2b,
Quality bitstream B _h generated in the encoder 12c is stored in the recording medium 13a. The changeover switch 14 normally selects and outputs the low image quality bit stream _BL of the encoder 12a, but when a retransmission request is received from the system controller 23 of the receiving terminal 20,
Among the high-quality bitstreams stored in the recording media 13 and 13a, the bitstream subjected to the optimum encoding process is selected and output.

Here, the encoder 1 for low image quality is used.
Although two encoders other than 2a that perform different encoding processes are provided, three or more rough encoders may be provided.

As described above, in the tenth embodiment,
By performing a plurality of encodings within the camera terminal 10, it is possible to select a bitstream that has been optimally encoded according to a retransmission request. The optimum encoding method is different depending on the form of image reproduction such as slow reproduction or enlarged reproduction. In the tenth embodiment, the encoding process is performed by the optimum method for each form of image reproduction. Since an encoder for performing the above and a recording medium for accumulating the bit stream output from them are provided, and these encoders simultaneously encode the video signals from the same camera 11 and accumulate them in the recording medium.
In response to the retransmission request from the receiving terminal 20 instructing the reproduction mode, the bit stream encoded by the method most suitable for the instructed reproduction mode can be delivered. It is possible to always receive a clear reproduced image.

[0115]

As described above, according to the video distribution system of the present invention, the camera terminal and the receiving terminal are connected via the network, and the bit stream generated from the video image taken by the camera terminal is sent to the receiving terminal. A video distribution system for distributing, wherein the camera terminal encodes a captured video signal to generate a first bit stream and a second bit stream that forms a video of higher image quality than the first bit stream. And normally delivers the first bit stream to the receiving terminal, and, in response to a retransmission request from the receiving terminal, generates a video from a video before a predetermined time before the time when the retransmission request is made. Since the second bit stream is delivered, normally, it is possible to suppress the bit amount by receiving with the minimum required image quality, and when a retransmission request is made, Although the amount of bits is large, a high-quality image is displayed and a clear image is obtained by rewinding and playing back to the required time, and the bit amount increases only when retransmitting. Only by doing so, it is possible to obtain a clear image from a necessary portion without constantly increasing the amount of bits to be obtained.

Further, according to the video distribution system of the present invention, the network includes an upper layer network connecting the camera terminal and the local server, and a lower layer network connecting the local server and the receiving terminal. The camera terminal encodes the captured video signal to generate a first bit stream and a second bit stream that forms a video of higher image quality than the first bit stream. The first and second bitstreams are generated and transmitted simultaneously to the local server via the upper layer network, and the receiving terminal receives the first and second bitstreams from the local server via the lower layer network. Since either of these is selectively delivered, a resend request for a high-quality video bitstream is sent. Load distributed to each local server,
It is possible to deliver high-quality video without delay.

Further, according to the video distribution system of the present invention, the plurality of camera terminals encode the picked-up video signals to form the first bit stream and the video of higher image quality than the first bit stream. And a second bitstream, and usually the first bitstream generated by a plurality of camera terminals is simultaneously delivered to the receiving terminal, and the receiving terminal designates one of the plurality of camera terminals and requests retransmission. If so, only the designated camera terminal delivers the second bit stream to the receiving terminal, so that the viewer views the images from a plurality of cameras in parallel and views the images from any one of the cameras. It is possible to select and receive the delivery of the high quality bit stream, easily select a desired video and view it with high quality.

Further, according to the video distribution system of the present invention, in the camera terminal, n bits (where n is an integer of 3 or more) encoded by different processing methods according to the video reproduction mode at the receiving terminal. A stream is generated, and a bit stream corresponding to the specified playback mode is delivered to the receiving terminal in response to a request from the receiving terminal that specifies the playback mode. The processed bit stream is distributed, and clear and high-quality image reproduction can be obtained in any image reproduction mode.

In order to achieve the above object, according to the camera terminal of the present invention, a camera terminal for delivering video information via a network, which outputs a video signal of a photographed subject, and the video signal A first encoder that encodes the video signal to generate a first bitstream; and a second encoder that encodes the video signal to generate a second bitstream of video of higher image quality than the first bitstream. The encoder and the recording medium for recording and reproducing the second bit stream are provided, and the first and second bit streams are used as the video information to be distributed. Therefore, in response to the request from the distribution destination. As a result, video of any image quality can be distributed, and the amount of bits obtained from the network is not constantly increased.

According to the camera terminal of the present invention,
A camera that outputs a video signal of a photographed subject, a first encoding process and a second encoding process of this video signal in a time division manner, and a first bit stream and a higher quality image than the first bit stream. Since a processor for generating a second bitstream of video and a recording medium for recording and reproducing the second bitstream are provided, the first and second bitstreams serve as video information to be distributed. It is possible to reduce the manufacturing cost by reducing the number of camera terminal parts.

Further, according to the camera terminal of the present invention, the camera for outputting the image signal of the photographed object, the image portion within the extraction range set for each frame from the image signal, and the extracted image is extracted. A signal processing unit for expanding the portion into one frame, a first encoder for encoding the output video signal of the signal processing unit to generate a first bit stream, and an encoding of this video signal output from the camera. , A second bitstream for generating a second bitstream of higher quality video than the first bitstream
Since the encoder and the recording medium for recording and reproducing the second bit stream are provided and the video information for distributing the first and second bit streams is used, the bit amount to be transmitted can be reduced, You can see the captured video in high quality when you need it.

Further, according to the camera terminal of the present invention, the camera for outputting the video signal of the photographed object, the first encoder for encoding the video signal to generate the first bit stream, and the video signal A second encoder that encodes the second bitstream to generate a second bitstream of a video having a higher image quality than the first bitstream, image recognition based on a video signal output from the camera, and a microphone provided in the camera. An image / voice recognition circuit for performing at least one of voice recognition based on a voice signal output from the recording medium, and a recording medium for recording and reproducing a second bit stream based on the recognition result of the image / voice recognition circuit. Since the first and second bit streams are used as video information to be distributed, the recording medium is recorded only when necessary. Since recording in is performed, to be reduced recording capacity of the recording medium, or alternatively, it is possible to lengthen the recording time of the recording medium.

Further, according to the camera terminal of the present invention, the camera for outputting the video signal of the photographed subject and the video signal are encoded by different processing methods to generate bit streams of different image quality.
And (n is an integer of 3 or more) encoders, and a recording medium for recording and reproducing the bit streams other than the bit stream having the lowest image quality, and video information for distributing n bit streams, and Therefore, it is possible to distribute the bitstream encoded by the processing method most suitable for the reproduction mode of the video requested by the distribution source, and it is possible to provide a good video regardless of the reproduction mode. .

In order to achieve the above object, according to the receiving terminal of the present invention, the receiving terminal receives a bit stream of video distributed via a network, and decodes the received bit stream into a video signal. It is equipped with a decoder, a display to which the decoded video signal is supplied to display the video, and a system controller for requesting resending of the video displayed on the display to the video distributor as high quality video. Therefore, when necessary, a high quality image can be retransmitted and the same image can be viewed again with high quality.

[Brief description of drawings]

FIG. 1 is a block diagram showing first and fourth embodiments of a video distribution system, a camera terminal and a receiving terminal according to the present invention.

FIG. 2 is a timing diagram showing an operation in the first embodiment shown in FIG.

FIG. 3 is a block diagram showing a second embodiment of a video distribution system, a camera terminal and a receiving terminal according to the present invention.

FIG. 4 is a block diagram showing a third embodiment of a video distribution system, a camera terminal and a receiving terminal according to the present invention.

5 is a timing diagram showing a processing operation of the processor in FIG.

FIG. 6 is a diagram showing operations of a video distribution system, a camera terminal and a receiving terminal according to a fifth embodiment of the present invention.

FIG. 7 is a block diagram showing a sixth embodiment of a video distribution system, a camera terminal and a receiving terminal according to the present invention.

FIG. 8 is a timing chart showing an operation of the sixth embodiment shown in FIG.

9 is a diagram showing a specific example of a screen displayed on the display of the receiving terminal in FIG.

FIG. 10 is a block diagram showing a seventh embodiment of a video distribution system, a camera terminal and a receiving terminal according to the present invention.

FIG. 11 is an explanatory diagram of a display image by a bit stream obtained by the encoder for low image quality according to the seventh embodiment shown in FIG.

FIG. 12 is an explanatory diagram of a video displayed in the video distribution system, the camera terminal and the reception terminal according to the eighth embodiment of the present invention.

FIG. 13 is a block diagram showing a ninth embodiment of a video distribution system, a camera terminal and a receiving terminal according to the present invention.

FIG. 14 is a block diagram showing a tenth embodiment of a video distribution system, a camera terminal and a receiving terminal according to the present invention.

FIG. 15 is a block diagram showing an example of a conventional video distribution system.

[Explanation of symbols]

10 camera terminals 11 cameras 12a-12c encoder 13, 13a recording medium 14 bit stream switch 15 processors 16 memory 16a, 16b encoding program 17 Signal processing unit 18 Image / Voice recognition circuit 20 camera terminal 21 decoder 22 Display 23 System Controller 30-32 network 40, 41 local buses 50 shooting range 51 Extraction range 52,53 people

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5C053 FA08 FA28 GA11 GB05 GB21                       JA03 JA07 KA05 KA24 LA01                       LA06 LA14                 5C054 CC05 DA06 EA01 EA05 EG00                       GB02 HA00 HA18                 5C064 BA04 BB05 BC04 BC18 BC20                       BD02 BD08                 5D015 KK02                 5K030 GA01 HA08 HB02 JT04 KA19                       LA01

Claims (11)

[Claims] 1. A video distribution system in which a camera terminal and a receiving terminal are connected via a network, and a bit stream generated from a video image captured by the camera terminal is distributed to the receiving terminal, wherein the camera terminal is an imaging device. The encoded video signal is encoded to generate a first bit stream and a second bit stream that forms a video image with higher image quality than the first bit stream, and the receiving terminal normally receives the first bit stream. A video delivery characterized by delivering a bitstream and, in response to a resend request from the receiving terminal, delivering a second bitstream from a video which is a predetermined time before the resend request. system. 2. A video distribution system in which a camera terminal and a reception terminal are connected via a network, and a bit stream generated from video captured by the camera terminal is distributed to the reception terminal, wherein the network is the camera. The camera terminal has a hierarchical structure composed of an upper layer network connecting the terminal and the local server, and a lower layer network connecting the local server and the receiving terminal. The video signal is encoded to generate a first bitstream and a second bitstream forming a video having a higher image quality than the first bitstream, and the first and second bitstreams are generated. It simultaneously transmits to the local server via the upper layer network, and the receiving terminal transmits from the local server to the lower layer network. A video distribution system, wherein one of the first and second bit streams is selectively distributed via a network. 3. A video distribution system in which a plurality of camera terminals are connected to a receiving terminal via a network, and a bit stream generated from video captured by the camera terminal is distributed to the receiving terminal. Encodes the captured video signal to generate a first bitstream and a second bitstream that forms a video of higher image quality than the first bitstream. Normally, the plurality of camera terminals When the generated first bit stream is simultaneously delivered to the receiving terminal and one of the plurality of camera terminals is designated by the receiving terminal and a resend request is made, only the designated camera terminal A video distribution system, wherein a second bit stream is distributed to the receiving terminal. 4. A video distribution system in which a camera terminal and a reception terminal are connected via a network, and a bit stream generated from a video image captured by the camera terminal is distributed to the reception terminal. N (where n is encoded by a different processing method depending on the video reproduction mode on the receiving terminal)
A bit stream of 3 or more) is generated, and the bit stream corresponding to the specified reproduction mode is distributed to the reception terminal in response to a request from the reception terminal that specifies the reproduction mode. Video distribution system. 5. A camera terminal for delivering video information via a network, the camera outputting a video signal of a photographed object, and a first bitstream for encoding the video signal to generate a first bitstream. Encoder, a second encoder that encodes the video signal to generate a second bitstream of a video having a higher image quality than the first bitstream, and records and reproduces the second bitstream. And a recording medium for storing the first and second bit streams as video information to be distributed. 6. A camera terminal for delivering video information via a network, wherein the camera outputs a video signal of a photographed subject, and the video signal is time-divided into a first encoding process and a second encoding process. A first bitstream, a processor that generates a second bitstream of video of higher image quality than the first bitstream, and a recording medium that records and reproduces the second bitstream. A camera terminal using the first and second bit streams as video information to be distributed. 7. A camera terminal for delivering video information via a network, comprising: a camera for outputting a video signal of a photographed subject; and a video portion within an extraction range set for each frame from the video signal. A signal processing unit that extracts and extends the extracted video portion to one frame, a first encoder that encodes an output video signal of the signal processing unit to generate the first bit stream, and the camera A second encoder that encodes the video signal output from the second bitstream and generates a second bitstream of a video having a higher image quality than the first bitstream, and recording and reproducing the second bitstream. And a recording medium for storing the first and second bit streams as video information to be distributed. 8. A camera terminal for delivering video information via a network, the camera outputting a video signal of a photographed subject, and a first bitstream encoding the video signal to generate a first bitstream. Based on the video signal output from the camera, and a second encoder that encodes the video signal to generate a second bitstream of a video of higher image quality than the first bitstream. An image / voice recognition circuit that performs at least one of image recognition and voice recognition based on a voice signal output from a microphone provided in the camera, and the second based on a recognition result of the image / voice recognition circuit. And a recording medium for recording and reproducing the bit stream of the first bit stream and the second bit stream as video information to be distributed. The camera terminal that. 9. A camera terminal for delivering video information via a network, wherein the camera outputs a video signal of a photographed subject, and the video signal is encoded by different processing methods, and bits of different image quality are obtained. N to create a stream
Video information for distributing the n bitstreams, provided with n (where n is an integer of 3 or more) encoders and a recording medium for recording and reproducing the bitstreams other than the bitstream having the lowest image quality. A camera terminal characterized by the following. 10. The switch according to claim 5, further comprising a changeover switch for selecting and distributing any one of the generated bitstreams, and switching the switch in response to a request from a distribution destination. A camera terminal characterized in that a switch is switched and controlled. 11. A receiving terminal for receiving a bit stream of video distributed via a network, comprising: a decoder for decoding the received bit stream into a video signal; and a video supplied with the decoded video signal. And a system controller for requesting a retransmission of a video displayed on the display as a high quality video to a video distribution source.