JP2002016921A - Moving picture encoding device and decoding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a moving picture encoding device and a decoding device capable of encoding and decoding a moving picture of high quality respectively. SOLUTION: Background memories 103 to 105 in which image are inputted and which store background images, an adder 111 which calculates a difference between the background image and the inputted images, a moving picture encoding circuit 113 which encodes the difference in a moving picture code, a still picture encoding circuit which encodes the stored background image in a still picture code, and a multiplexer 115 which multiplexes the moving picture code line and the still picture code line into a multiplex code line, are provided, by which moving picture encoding can be carried out without deteriorating a background image in resolution.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving picture coding apparatus and a moving picture decoding apparatus used in the field of digital video communication such as a video telephone system, a video conference system, and a remote monitoring apparatus.

[0002]

2. Description of the Related Art With the recent development of digital communication technology, digital communication services are required to have higher service quality and lower costs for providing them.

As an example, a digital video communication service using a terrestrial communication path will be described as an example. A popular digital video communication service using an ISDN network is well known. Generally, in the case of an ISDN network, 128 kbp
s, and the digital video communication service terminal transmits the video after compressing the video to 128 kbps. The most common video compression method used in the ISDN network is the international standardization method H.264. 320. H.
A system using the 320 is implemented, for example, as a videophone, and can realize a bidirectional digital video communication service while keeping terminal and line costs low.

FIG. 4 shows a conventional example of a moving picture coding apparatus and a moving picture decoding apparatus using an ISDN network.

[0005] As shown in FIG.
NTSC / CIF conversion circuit 301, moving picture coding circuit 30
2. A multiplexing unit 303, and the moving picture decoding apparatus includes a demultiplexing unit 304, a moving picture decoding circuit 305, a CIF / N
It is configured by a TSC conversion circuit 306.

Next, the operation of the above conventional example will be described for each of the moving picture coding apparatus and the moving picture decoding apparatus.

[0007] The input video input to the moving picture coding apparatus is sent to an NTSC / CIF conversion circuit 301.
The NTSC / CIF conversion circuit 301 compresses image information by performing image thinning. That is, in the case of a normal NTSC signal, the number of pixels per frame is seven.
Although it is 04 × 480 pixels, it is compressed to 352 × 288 pixels by thinning it out to a CIF signal. NTSC / CI
The input video compressed in the F-conversion circuit 301 is then sent to the moving picture coding circuit 302. Here, for example, ITU-T Recommendation H. 261 is performed to further compress the CIF signal in the time and space directions.

[0008] The video code string compressed and generated by the moving picture coding circuit 302 is sent to a multiplexing unit 303, multiplexed with other control signals and the like, and sent out as a transmission code string to a transmission path. When the transmission path is ISDN, the input video is compressed to about 1/1500 of the original input video through these processes, and can be transmitted through an ISDN line which is a low-rate communication path such as 64 kbps or 128 kbps. Become.

Next, a moving picture coding apparatus will be described. The transmission code string transmitted via the transmission path is transmitted to the separation unit 3
04. The separation unit 304 separates the compressed video code string and sends it to the video decoding circuit 305. In the video decoding circuit 305, for example, ITU-T Recommendation H.264 2
The moving image decoding process shown in FIG. 61 is performed, and the video code string compressed in the time direction and the space direction is converted into a CIF.
Decode to a signal. CIF signal is CIF / NTSC
In the conversion circuit 306, the original NTSC signal is restored.

As described above, the above-mentioned conventional moving picture coding apparatus and moving picture decoding apparatus realize a digital video communication service via a transmission path.

[0011]

However, in the above-mentioned conventional moving picture coding apparatus, the whole input picture is treated as a moving picture and transmitted. Therefore, in order to perform moving image encoding suitable for a low-rate communication channel, for example, NTSC / CIF conversion is performed on the entire input image to reduce the resolution, and further, the CIF signal is subjected to moving image encoding. As a result, the resolution must be reduced even for a portion such as a background that does not need to be treated as a moving image, resulting in deterioration of the overall image quality including moving image encoding.

The present invention has been made to solve such a problem, and an object of the present invention is to provide a moving picture coding apparatus capable of performing moving picture coding without reducing the resolution of a background picture.

[0013]

A moving picture encoding apparatus according to the present invention calculates a difference between the background image and the input image, a background storage means for storing a background image, an input means for inputting a video image, and the like. Difference calculating means, moving picture coding means for moving picture coding the difference, still picture coding means for still picture coding the stored background image, moving picture coded moving picture code string and the still picture Multiplexing means for multiplexing the encoded still image code sequence as a multiplexed code sequence.

With this configuration, the background image that does not change over time is encoded as a still image, the image portion that changes over time is encoded as a moving image, and the difference from the background image is calculated to reduce the amount of code. By performing the multiplexing of the still image information and the moving image information, it is possible to realize both the encoding having a high spatial resolution and the encoding of a moving image as a moving image. Further, the still image information and the moving image information can be transmitted at the same time, and the transmission of the still image information only needs to be performed once, and there is no need to repeat the transmission periodically.

Further, in the moving picture coding apparatus according to the present invention, the background storage means stores a plurality of background images, and calculates a difference between the input video and the plurality of background images for each background image. Means, a minimum value selecting means for selecting the minimum difference with the smallest difference and generating this selection information, and a background image selecting means for selecting the stored background image based on the selection information, Difference calculating means for calculating a difference between the selected background image and the input image, the still image coding means for coding the selected background image as a still image, and the multiplexing means for forming a multiplexed code string. The configuration is characterized in that the selection information is multiplexed.

With this configuration, a background image having the smallest difference from the input image can be selected from a plurality of background images, and the difference from the background image can be encoded as moving image information, thereby reducing the code amount. By multiplexing the selection information of the background image with the moving image information, it is possible to easily decode the multiplexed code sequence, to eliminate the need for re-encoding the background image, and to effectively use the multiplexed code sequence. it can.

Further, the moving picture coding apparatus of the present invention generates update information for controlling the update of the background image stored in the background storage means, and controls the update of the background image based on the update information. The image processing apparatus further includes a background image update control unit, wherein the multiplexing unit multiplexes the still image code string and the update information according to the update information.

According to this configuration, when an appropriate background image is not stored for the input video, the background image is stored in the background storage means as a new background image, and the background image is encoded as still image information and the update information. By multiplexing
It can be transmitted as new background information, and can perform encoding processing corresponding to the input video.

The moving picture coding apparatus according to the present invention further comprises a designation information input means for inputting background image designation information selected by the minimum value selection means and background image update request information updated by the background image update control means. It is a configuration characterized by comprising:

With this configuration, a background image to be used as a background image and an update request for a stored background image can be input, and the designated background image can be encoded. Image to be updated, or a new background image can be updated.

Furthermore, in the moving picture coding apparatus according to the present invention, the multiplexing means may include a still picture transmission code quantity for transmitting still picture information, among all multiplex code quantities that can be transmitted per unit time; The present invention is characterized in that a moving image transmission code amount for transmitting moving image information is multiplexed at an arbitrary ratio based on still image information and moving image information.

With this configuration, the multiplexing ratio of the still image information and the moving image information can be adjusted according to the content. For example, when transmitting a background image over a long period of time, by reducing the ratio of still image information per unit time, it is possible to increase the ratio of moving image information, and to transmit high-quality moving image information. Can be. Conversely, when the moving image information can be compressed to a small size, the ratio of the still image information can be increased, and the still image information can be transmitted in a short time.

Also, in the moving picture coding apparatus according to the present invention, the multiplexing means may include a still picture transmission code quantity for transmitting still picture information among all the multiplexed code quantities that can be transmitted per unit time; The configuration is characterized in that a moving image transmission code amount for transmitting moving image information is multiplexed at an arbitrary ratio, and a ratio information code sequence indicating the ratio is multiplexed into a multiplexed code sequence.

With this configuration, by decoding the ratio information code string, it is possible to easily decode the still picture information and the moving picture information.

The moving picture decoding apparatus according to the present invention comprises: a separating means for separating, from a multiplexed code string, a moving picture code string in which moving picture information is encoded and a still picture code string in which still picture information is encoded;
Moving picture decoding means for decoding the moving picture code string into moving picture information, still picture decoding means for decoding the still picture code string into still picture information, and the still picture decoded still picture information And storage means for storing the moving picture information obtained by decoding the moving picture information to the stored still picture information.

With this configuration, it is possible to decode a background image and moving image information encoded as difference information between the background image, and decode an image encoded at a high spatial resolution and a moving image with motion. can do.

In the moving picture decoding apparatus according to the present invention, the separating means separates selection information for selecting a specific background image from a plurality of background images from the multiplexed code string, and the background storage means stores the plurality of background images. A background image selecting unit that stores an image and selects the stored background image based on the selection information, wherein the adding unit adds the moving image information obtained by decoding the moving image to the selected background image. It is a configuration characterized by the following.

With this configuration, a specific background image is selected from a plurality of background images according to the selection information, and moving image information is added to the background image. Therefore, the plurality of background images are stored, and the background image is stored by the input video. Switching can be performed, transmission / reception of the background image can be minimized, and the multiplexed code string can be used effectively.

In the moving picture decoding apparatus according to the present invention, the separating means separates update information for controlling the updating of the background image from the multiplexed code string, and updates the background image stored in the background storage means. A configuration is provided that includes a background image update control unit that updates based on information.

With this configuration, when an image completely different from the stored background image is decoded, the still image information is newly decoded by the update information, so that the image is not tied to the stored background image. A decoding process corresponding to the input video can be performed.

Furthermore, in the moving picture decoding apparatus according to the present invention, the separating means may further include a still picture transmission code quantity for transmitting still picture information, The video transmission code amount for transmitting information is characterized by separating video information and still image information from a multiplexed code string multiplexed at an arbitrary ratio based on still image information and video information. The configuration is as follows.

With this configuration, it is possible to separate and decode even a multiplexed code string multiplexed at an arbitrary ratio based on the still picture information and the moving picture information. It is also possible to decode a multiplexed code string emphasizing.

Also, in the moving picture decoding apparatus according to the present invention, the separating means may further include a still picture transmission code quantity for transmitting still picture information, The ratio information code sequence is separated from the multiplexed code sequence in which the moving image transmission code amount for transmitting information and the ratio information code sequence indicating the ratio are multiplexed, and a moving image is generated based on the ratio information code sequence. This configuration is characterized in that information and still image information are separated.

According to this configuration, moving image information and still image information can be easily separated by the ratio information code string.

The moving picture coding apparatus according to the present invention comprises: a background storage means for storing a plurality of background images; an input means for inputting a video; a time information generating means for generating time information; Background image selecting means for selecting the background image and generating this selection information, difference calculating means for calculating a difference between the selected background image and the input image,
Moving image encoding means for encoding the difference in a moving image, still image encoding means for still image encoding the selected background image, the moving image encoded moving image code string and the still image encoded still image Multiplexing means for multiplexing the image code string and the selection information as a multiplexed code string.

With this configuration, a plurality of background images can be prepared for each time, and the background image can be switched for each time, updating of the background image can be minimized, and the moving picture coding efficiency can be reduced. Can be enhanced.

Further, the moving picture coding apparatus according to the present invention comprises: a background storage means for storing a plurality of background images; an input means for inputting a video; a spatial information generating means for generating spatial information; Background image selecting means for selecting the background image based on the selected background image and generating the selection information, difference calculating means for calculating a difference between the selected background image and the input video, and a moving picture code for coding the difference as a moving picture Means,
A still image encoding unit that encodes the selected background image as a still image, a moving image code sequence encoded with the moving image, the still image encoded still image code sequence, and the selection information as a multiplexed code sequence. Multiplexing means for multiplexing.

With this configuration, a plurality of background images can be prepared for each space, and the background image can be switched for each space. Even if the input image is switched due to a change in the direction of the camera, the background image is updated. Can be minimized, and the moving picture coding efficiency can be improved.

Further, the moving picture coding apparatus according to the present invention comprises: a background storage means for storing a plurality of background images; an average value calculating means for calculating an average value image of the plurality of background images; Difference calculating means for calculating a difference from the background image, difference coding means for coding the difference, average value image coding means for coding an average value image of the background image, and the encoded Multiplexing means for multiplexing the differential code sequence and the coded average image code sequence as a multiplexed code sequence.

According to this configuration, an average value of a plurality of background images is obtained, and a difference from this average value is obtained for encoding.
Encoding efficiency can be improved, for example, when many approximate images are transmitted.

[0041]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a moving picture coding apparatus according to the present invention.

As shown in FIG. 1, the main moving picture coding apparatus 1
00 is an adder 111, an NTSC / CIF conversion circuit 11
2, moving picture coding circuit 113, still picture coding circuit 114,
A multiplexing unit 115 and an encoding-side background processing unit 150 are provided.
1. Background memory update control circuit 102, first background memory 1
03, the second background memory 104, the N-th background memory 105,
Background memory selection circuit 106, first prediction error calculation circuit 10
7, a second prediction error calculation circuit 108, an Nth prediction error calculation circuit 109, and a minimum value selection unit 110.

Next, the operation of the main moving picture coding apparatus 100 will be described. In the main moving picture coding apparatus 100, a plurality of background memories 103,
A background image having the smallest difference between the input image and the background image stored in the background memory, encoding the difference between the input image and the background image as a moving image, and multiplexing the background image with the background image. To be able to do so, the input video is sent to the adder 111 and the background processor 150.

In the background processing section 150, the input image is processed by the background generation circuit 101, the first prediction error calculation circuit 10
7, input to the second prediction error calculation circuit 108 and the N-th prediction error calculation circuit 109.

The input image input to the background generation circuit 101 is generated as a background image, the background memory update request information is output to the background memory update control circuit 102, and the first background memory 103 and the second background memory 104 , To the N-th background memory 105. Background memory 103 ~
The 105 has a plurality of background memories as described above, so that a plurality of background images can be stored. The background memories 103 to 105 are the background memory update control circuit 1
02 and, if necessary, the background memory 103 to
A predetermined background memory 105 is selected, and the content is updated.

The first prediction error calculation circuit 107, the second prediction error calculation circuit 108, and the N-th prediction error calculation circuit 109 determine which background memory the input image is close to and store the input image. And background memories 103 to 10
The calculation of the prediction error with respect to the background image stored in No. 5 is performed. The calculated prediction error is calculated by the prediction error calculation circuit 10.
7 to 109 are output to the minimum value selection unit 110. In the minimum value selection unit 110, the prediction error calculation circuit 107
１０９109 are compared, a minimum value is obtained, and selection information determined to have the smallest prediction error is output.

To update the contents stored in the background memories 103 to 105, the selection information is updated by the background memory update control circuit 10.
2 to control the content update.

The selection information output from the minimum value selection unit 110 is input to the background memory selection circuit 106, and the background memory selection circuit 106 selects and selects the background memory information output from the background memories 103 to 105. The selected background memory information is output to the adder 111. Also,
The background memory 103 is controlled by the background memory update control circuit 102.
When any one of .about.105 is updated, the updated updated background memory information is output to the still image encoding circuit 114.

The still image encoding circuit 114 encodes the updated background memory information as still image information, and transmits only the updated background memory information as a still image.

The adder 111 calculates the difference between the input video and the selected background memory information determined to have the smallest prediction error from the input video. In order to transmit this difference information as a moving image, the difference is calculated by the NTSC / CIF conversion circuit 1.
12 and converted to a CIF signal by the NTSC / CIF conversion circuit 112, and the converted CIF signal is
The moving picture coding circuit 113 performs moving picture coding.

In the multiplexing section 115, the moving picture coding circuit 11
3 is multiplexed with the moving image information encoded in step 3, the update information in the background memory, the still image information encoded by the still image encoding circuit 114, and the selection information, and outputs the result to the transmission path as a transmission code string.

FIG. 2 shows an embodiment of the moving picture decoding apparatus according to the present invention.

As shown in FIG. 2, the main video decoding device 2
00 denotes a separating unit 201, a moving image decoding circuit 202, a CIF
/ NTSC conversion circuit 203, an adder 210, and a decoding-side background processing unit 250.
Are a still image decoding circuit 204, a background memory update control circuit 205, a first background memory 206, and a second background memory 20
7. Nth background memory 208, background memory selection circuit 209
have.

Next, the operation of the main moving picture decoding apparatus 200 will be described. The main moving picture decoding apparatus 200 includes a plurality of background memories 206, 207, and 208 so that an output video can be generated by adding a background picture selected by the selection information and a transmitted moving picture. Therefore, the transmission code string is sent to the separation unit 201, the moving image information output from the separation unit 201 is sent to the moving image decoding circuit 202, and the other code strings are sent to the decoding side background processing unit 250.

In the decoding side background processing section 250,
The still image information separated by the separation unit 201 is input to the still image decoding circuit 204, where the still image is decoded as background information, and the first background memory 206, the second background memory 207,
The data is output to the N-th background memory 208. The update information separated by the separation unit 201 is input to the background memory update control circuit 205, and when the background memory needs to be updated, the desired background memory of the background memories 206 to 208 is updated according to the update information. The selection information separated by the separation unit 201 is input to the background memory selection circuit 209, and the background memory selection circuit 209 selects a background image based on the selection information from the background images output from the background memories 206 to 208, respectively. Output to adder 210.

The moving picture information is decoded into a CIF image by the moving picture decoding circuit 202, and the CIF / NTSC conversion circuit 2
03, and the CIF image is returned to the NTSC signal by the CIF / NTSC conversion circuit 203.
Is output to The converted NTSC signal is added to the selected background image in an adder 210,
It is reproduced as an SC output video.

With the above configuration and processing, a portion that does not need to be treated as a moving image, such as a background, can be transmitted as a still image without changing the resolution, and only the difference from this background can be encoded as a moving image. In particular, in the transmission of a moving image using a low-rate communication channel, it is possible to achieve both high spatial resolution and moving image quality per second.

Further, in the present embodiment, the transmission code amount of the still image information is smaller than the transmission code amount of the moving image information per unit time among all the transmission code amounts that can be transmitted per unit time. May be. This means that if you try to transmit still image information while maintaining high image quality, the amount of transmitted code will increase, but the information to be transmitted as still image information is information with a small amount of change with respect to the time axis, so it is transmitted per unit time. This is because the transmission code amount to be set can be set smaller than the transmission code amount of the moving image information.

FIG. 3 shows an embodiment of the transmission code amount between the moving picture information and the still picture information. For example, when transmitting the updated background memory information as Ns-bit still image information, this is divided into time T and transmitted. The transmission code amount of the still image information among the Nt bits of the entire transmission code string per unit time is expressed as Ns / T. The transmission code string of the moving image information per unit time is Nm = Nt-Ns / T,
When Nt >> Ns / T, that is, when Nt is Ns / T
If Nm is large enough, Nm can obtain a sufficient speed for transmitting moving image information.

Also, the total transmission code string Nt per unit time
Is represented by a transmission code string Nm of moving image information and a transmission code string Ns / T of still image information. However, Nm and Ns / T may or may not be constant. Absent. Nm
For example, when a transmission code amount of moving image information is small, a large amount of transmission code amount of still image information is transmitted, and a still image is transmitted. The information may be transmitted quickly, and when the minimum transmission code of the still image information is small,
Control may be performed to transmit a large amount of transmission code of moving image information.

The ratio between Nm and Ns / T may be multiplexed in a multiplexing unit as a ratio information code string. The transmission code sequence transmitted from the video encoding device having a multiplexing unit capable of multiplexing the ratio information code sequence is sent to the video decoding device, and the separation unit of the video decoding device is Based on this ratio information code string, Nm and Ns / T are configured to be separated.

When the moving picture coding apparatus and the moving picture decoding apparatus according to the present invention are connected to a fixed camera and used for remote monitoring of a fixed point, the image to be picked up is always spatially constant. It is. Therefore, the number of updates of the background memory is small, and the merit obtained by the present invention can be maximized.

Further, for example, images picked up by a fixed camera are distinguished by time. That is, the daytime is bright,
Night is a dark picture. According to the present invention, by providing a plurality of background memories for these images that change with time, these background memories can be controlled separately for each time. For example, the background at 7:00 am is stored in the first background memory, the background at 3:00 pm is stored in the second background memory, and so on.
Thus, by newly providing a background memory selection means for each time that performs control so as to select the background memory at each predetermined time, the updating of the background memory can be minimized, and the moving picture coding efficiency can be reduced. Can be further enhanced.

Further, by providing a plurality of background memories, a space-based background memory selecting means for controlling these background memories for each space is newly provided.
When combined with a camera that has functions such as pan / tilt / zoom, the difference between the input video and the background memory can be reduced by controlling so that the background memory is allocated to each direction of the camera. As a result, the value of the difference to be transmitted as a moving image can be reduced, and the moving image encoding efficiency can be further improved.

In the background generation circuit, general background generation means can be used. For example, a means for calculating an average value of pixel values at the same position spatially in the time direction is provided, and the average value is used as a background value. The moving picture coding apparatus can be generated and applied to the moving picture coding apparatus.

These time-based background memory selecting means, space-based background memory selecting means, and background generating means may be used in combination.

[0068]

As described above, according to the present invention, a background image that does not change over time is encoded as a still image, an image portion that changes over time is encoded as a moving image, and the difference between the background image and the background image is encoded. , The multiplexing of the still image information and the moving image information realizes both the encoding having a high spatial resolution and the encoding of a moving image as a moving image. It is possible to provide a moving picture coding apparatus having an excellent effect that the moving picture coding can be performed.

Further, the present invention can decode a background image and moving image information encoded as difference information between the background image and the moving image with high spatial resolution. It is possible to provide a moving picture decoding apparatus having an excellent effect that it is possible to decode a moving picture.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a moving picture coding apparatus according to the present invention.

FIG. 2 is a block diagram showing one embodiment of a moving picture decoding apparatus according to the present invention.

FIG. 3 is a diagram illustrating a transmission code string of moving image information and still image information according to one embodiment.

FIG. 4 is a diagram illustrating an example of a conventional video encoding device and a conventional video decoding device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 moving image encoding device 101 background generation circuit 102 background memory update control circuit 103 first background memory 104 second background memory 105 Nth background memory 106 background memory selection circuit 107 first prediction error calculation circuit 108 second prediction error calculation circuit 109 Nth prediction error calculation circuit 110 minimum value selection unit 111 adder 112 NTSC / CIF conversion circuit 113 moving image coding circuit 114 still image coding circuit 115 multiplexing unit 150 coding side background processing unit 200 moving image decoding device 201 Separation unit 202 Video decoding circuit 203 CIF / NTSC conversion circuit 204 Still image decoding circuit 205 Background memory update control circuit 206 First background memory 207 Second background memory 208 Nth background memory 209 Background memory selection circuit 210 Adder 250 Decoding Background processing unit 30 Reference Signs List 1 NTSC / CIF conversion circuit 302 Video encoding circuit 303 Multiplexing unit 304 Demultiplexing unit 305 Video decoding circuit 306 CIF / NTSC conversion circuit Nt Total transmission code amount per unit time Nm Transmission code amount of video information per unit time Ns Transmission code amount of still image information T Time required to transmit still image information

Claims (14)

[Claims] 1. A background storage unit for storing a background image, an input unit for inputting a video, a difference calculation unit for calculating a difference between the background image and the input image, and a moving image code for coding the difference in a moving image A still image encoding unit that encodes the stored background image as a still image, and a multiplexed code sequence that multiplexes the moving image encoded moving image code sequence and the still image encoded still image code sequence. And a multiplexing unit for performing multiplexing. 2. The moving image encoding apparatus according to claim 1, wherein the background storage unit stores a plurality of background images, and calculates a difference between the input video and the plurality of background images for each background image. Error calculating means, a minimum value selecting means for selecting a minimum difference that minimizes the difference, and a minimum value selecting means for generating the selection information; and a background image selecting means for selecting the stored background image based on the selection information. Wherein the difference calculation means calculates a difference between the selected background image and the input image, and the still image encoding means encodes the selected background image as a still image; Means for multiplexing the selection information into a multiplexed code sequence. 3. The moving picture coding apparatus according to claim 1, wherein update information for controlling updating of the background image stored in said background storage means is generated, and said background image is updated based on said update information. A moving image encoding apparatus, comprising: background image update control means for controlling update; wherein the multiplexing means multiplexes the still image code string and the update information according to the update information. 4. The moving picture coding apparatus according to claim 3, wherein said background image specifying information selected by said minimum value selecting means and background image update request information to be updated by said background image updating control means are input. A moving image encoding apparatus comprising: 5. The moving picture coding apparatus according to claim 1, wherein said multiplexing means outputs the still picture information among all multiplexed code amounts that can be transmitted per unit time. And the moving image transmission code amount for transmitting moving image information,
A moving picture coding apparatus characterized in that the moving picture is multiplexed at an arbitrary ratio based on still picture information and moving picture information. 6. The moving picture coding apparatus according to claim 1, wherein the multiplexing means outputs the still picture information among all multiplexed code amounts that can be transmitted per unit time. And the moving image transmission code amount for transmitting moving image information,
A moving picture coding apparatus characterized by multiplexing at an arbitrary ratio and multiplexing a ratio information code sequence indicating the ratio into a multiplexed code sequence. 7. Demultiplexing means for separating a moving image code string in which moving image information is encoded from a multiplexed code string and a still image code string in which still image information is encoded, and converting the moving image code string into moving image information into moving image information. Moving image decoding means for decoding; still image decoding means for still image decoding the still image code string into still image information; background storage means for storing the still image decoded still image information; A moving image decoding apparatus comprising: adding means for adding the moving image information obtained by decoding the moving image to the stored still image information. 8. The moving picture decoding apparatus according to claim 7, wherein said separating means separates selection information for selecting a specific background image from a plurality of background images from a multiplexed code string, and said background storage means A background image selecting unit that stores the plurality of background images, and selects the stored background image based on the selection information, wherein the adding unit performs the moving image decoding on the selected background image. A moving image decoding apparatus characterized by adding moving image information. 9. The moving picture decoding apparatus according to claim 7, wherein the separating unit separates update information for controlling updating of a background image from a multiplexed code string, and stores the update information in the background storage unit. A moving image encoding apparatus comprising: a background image update control unit that updates a background image based on the update information. 10. The moving picture decoding apparatus according to claim 7, wherein the separating unit converts the still picture information among all multiplexed code amounts that can be transmitted per unit time. The still image transmission code amount to be transmitted, and the moving image transmission code amount for transmitting the moving image information, the moving image information and the moving image information are multiplexed at an arbitrary ratio based on the still image information and the moving image information. A moving picture decoding apparatus, which separates still picture information from moving picture information. 11. The moving picture decoding apparatus according to claim 7, wherein the separating unit converts the still picture information among all multiplexed code amounts that can be transmitted per unit time. The ratio information code sequence is separated from the multiplexed code sequence in which the still image transmission code amount to be transmitted, the moving image transmission code amount for transmitting the moving image information, and the ratio information code sequence indicating the ratio are multiplexed. A moving image decoding apparatus for separating moving image information and still image information based on the ratio information code string. 12. A background storage means for storing a plurality of background images; an input means for inputting a video; a time information generating means for generating time information; and selecting the background image based on the time information; A background image selecting unit that generates the selection information; a difference calculating unit that calculates a difference between the selected background image and the input image; a moving image encoding unit that encodes the difference as a moving image; A still image encoding unit that encodes a background image as a still image, and multiplexes the moving image encoded moving image code sequence, the still image encoded still image code sequence, and the selection information as a multiplexed code sequence. A moving picture coding apparatus comprising multiplexing means. 13. A background storing means for storing a plurality of background images; an input means for inputting a video; a spatial information generating means for generating spatial information; and selecting the background image based on the spatial information; A background image selecting unit that generates the selection information; a difference calculating unit that calculates a difference between the selected background image and the input video; a moving image encoding unit that encodes the difference as a moving image; A still image encoding unit that encodes a background image as a still image; a multiplex that multiplexes the moving image encoded moving image code sequence, the still image encoded still image code sequence, and the selection information as a multiplexed code sequence. A moving picture coding apparatus comprising: a coding means. 14. A background storing means for storing a plurality of background images; an average value calculating means for calculating an average value image of the plurality of background images; and a difference for calculating a difference between the average value image and the background image. Calculating means, difference encoding means for encoding the difference, average value image encoding means for encoding the average value image of the background image, the encoded difference code sequence and the encoded average Multiplexing means for multiplexing a value image code string as a multiplexed code string.