JP2553813B2 - Video signal encoding device and video signal decoding / reproducing device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video signal coding apparatus used when a video signal is compression coded and recorded on a disk, and a video signal which is compression coded and recorded on a disk. The present invention relates to a video signal decoding / reproducing device.

[0002]

2. Description of the Related Art With the development of digital storage media, methods for compressing and recording long-time moving images on these recording media have been studied. International Organization for Standardization (ISO)
In this regard, the standardization activity of the moving picture coding system has been carried out in MPEG of the International Electrotechnical Commission (IEC), for example, "ISO / IEC DIS 11172".

The MPEG encoding algorithm uses predictive encoding based on motion-compensated interframe prediction. Inter-frame prediction is effective for compressing moving image information, but cannot always realize the random access function because it always uses the information of the previous frame. So GROUP OF PICTURES
An image unit composed of a plurality of image frames called (hereinafter referred to as GOP) is provided, and the first frame encoded in each GOP is always intraframe encoded.

As shown in FIG. 13A, each GOP has three types of coded frames, namely, an intra-frame coded frame (INTRA-CODED PICTURE, hereinafter referred to as I frame) and an inter-frame coded frame (PREDICTIVE-). CODED PICTURE,
Hereinafter referred to as P frame), frame interpolated coded frame (BIDIRECTIONALLY PREDICTIVE-CODED PICTURE, hereinafter B
It is called a frame). In FIG. 13, 1
An example in which a GOP is composed of 12 frames and P frames are inserted every two frames is shown.

By the way, since the I frame is intra-frame encoded, it can be reproduced without reference to other frames during decoding. Further, since the P frame is interframe-coded by referring to the I frame or P frame that is temporally preceding, it is necessary that the I frame or P frame that is temporally preceding is decoded at the time of decoding. is there. Further, since the B frame is encoded by using the I frame or P frame in both the temporally front and rear directions, the I frame or the P frame temporally before or after the time used for prediction is decoded at the time of decoding. If it is not decrypted, it cannot be decrypted.
Therefore, encoding is performed in the order shown in FIG.

[0006]

However, in the conventional configuration as described above, even if the GOP is reproduced in the reverse order from the recording medium in order to perform the backward reproduction, the decoding is performed at the time of decoding. There was a problem that some frames could not be created. That is, taking the case as shown in FIG. 13B as an example, the B frames with frame numbers 10 and 11 must be decoded using the P frame with frame number 9 and the I frame with frame number 12. However, since the data of the P frame with the frame number 9 is an image belonging to another GOP and has not been decoded yet, the B frame images of these frame numbers 10 and 11 cannot be decoded.

In view of the above point, the present invention has an object to provide a video signal decoding / reproducing apparatus and a video signal encoding apparatus capable of reverse reproduction.

[0008]

According to a first aspect of the present invention, there is provided a video signal decoding / reproducing apparatus in which a plurality of consecutive frames of a moving image signal are used as one image unit and compressed by predictive coding and recorded on a recording medium. The moving image data reproducing means capable of reproducing the reproduced moving image data for each image unit, the first decoding means for performing the intra-frame decoding of the reproduced signal, and the temporally forward frame of the reproduced signal. Second decoding means for performing inter-frame decoding using the prediction of R, and inter-frame decoding using the prediction of the reproduced signal from the temporally forward frame and the temporally backward frame. Is decrypted by the third decryption means for performing encryption and the first decryption means.
The decoded image and the second decoding means.
Decoded image that stores both or one of the decoded images
A storage means and a plurality of recovery images stored in the decoded image storage means.
The interpolated image is created using the two predetermined images of the encoded images.
Image decoding means for obtaining and third decoding at the time of reproduction in the reverse direction
How to output part or all of the image decoded by
Control to output the interpolated image by the image interpolation means
And a means for doing so.

In the video signal decoding / reproducing apparatus of the second invention, a plurality of consecutive frames of a moving image signal are used as one image unit, and the moving image is compressed by predictive coding and recorded on a recording medium. Using moving image data reproducing means capable of reproducing data for each image unit, first decoding means for performing intra-frame decoding of a reproduced signal, and prediction of a reproduced signal from a temporally forward frame. Second decoding means for performing inter-frame decoding by means of inter-frame decoding, and inter-frame decoding using the prediction of a reproduced signal from a temporally forward frame and a temporally backward frame. The decoding unit of No. 3 and the image unit immediately before the image unit to be reproduced and the image unit to be reproduced at the time of reproduction in the reverse direction are equal to or less than a time period during which an image of one image unit is output. To play with A configuration in which a Gosuru means.

Further, the video signal coding apparatus of the third invention comprises a first coding means for performing intra-frame coding by using a plurality of consecutive frames of a moving picture signal as one image unit, and temporally. Both the second coding means for performing interframe predictive coding by utilizing the correlation with the forward frame and the correlation with the temporally forward frame and the temporally backward frame. And third coding means for performing inter-frame predictive coding by utilizing the following, and fourth coding means for performing inter-frame predictive coding by utilizing the correlation with the frame in the temporally backward direction. An image of one frame in one image unit composed of a plurality of frames is encoded by the first encoding means, and every second frame from the frame is encoded by the second encoding means every n frames. And the n frame before the frame Over arm is the encoded in the fourth coding means is configured to include a means for switching the coding method to encode the other frames in the third coding means.

[0011]

According to the first aspect of the present invention, in the case of forward reproduction, decoding is performed by the first to third decoding means, and in reverse reproduction, the order of image units is reversed. I.e., the n-th image unit, the (n-1) -th image unit, the (n-2) -th image unit, and so on, and the third decoding means. Instead of outputting a part or all of the decoding by, the control is performed so as to output the interpolated image created from the image decoded by the first decoding means and the second decoding means.

According to the second aspect of the present invention, with the above-described structure, when the image in the image unit is decoded in the reverse direction, the image unit immediately before the image unit to be reproduced is reproduced. By controlling such image units to be reproduced in a time period equal to or less than the period for outputting the image units, it is possible to decode and reproduce the data of all the frames included in the image units to be reproduced.

According to a third aspect of the present invention, with the above-described configuration, the image of one frame in one image unit composed of a plurality of consecutive frames is encoded by the first encoding means, The second encoding means encodes every nth frame from the frame encoded by the second encoding means, and the nth frame before the frame encoded by the first encoding means is the fourth frame. Encoded by the encoding means of
The other frames are controlled to be coded by the third coding means. By doing this, all the images belonging to one image unit are decoded using only the images in that image unit, so that when decoding, each image unit can be decoded independently, Reverse reproduction can be easily performed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a video signal decoding / reproducing apparatus according to the first embodiment of the present invention.

In FIG. 1, 101 is a video disk,
102 is a spindle motor, 103 is a rotation controller for controlling the spindle motor 102, 104 is a pickup,
105 is a feed motor for moving the pickup 104, 106 is a feed control unit for controlling the feed motor 105, 107 is a focus / tracking control unit, 108
Is a signal processing unit, 109 is an image decoding processing unit, 110 is an output switching unit, 111 is a system controller, 112
Is an image interpolation processing unit, and 113 to 117 are image memories.

The operation of the video signal decoding / reproducing apparatus of this embodiment constructed as described above will be described below.
First, a video signal is recorded on the video disc 101 in a format as shown in FIG. 2, for example. In FIG. 2, reference numeral 201 is an address information signal, and reference numeral 202 is a video information signal for 1 GOP which is compression-coded and added with an error correction code and the like.

The rotation control unit 103 controls the spindle motor 102 to rotate the video disk 101 at a predetermined rotation speed. In response to a command from the system controller 111, the feed control unit 106 controls the feed motor 105 to move the pickup 104 to a position to be reproduced, and the focus tracking control unit 107 controls focus and tracking. From the system controller 111, for example, by designating the address of the address information signal 201 shown in FIG. 2, the position of the track or sector can be designated in GOP units. As described above, it is possible to access in units of GOP, but during normal reproduction, if the first jump to the beginning of the desired GOP is made, the data may be reproduced in order.

On the other hand, the reproduction signal output from the pickup 104 is subjected to processing such as amplification, waveform shaping, clock reproduction, data demodulation and error correction in the signal processing unit 108, and the image decoding processing unit 109 is subjected to a data string. Supplied as.

FIG. 3 shows the image decoding processing unit 1 during normal reproduction.
09 data stream and image memories 113-117
It shows an example of the contents of. In this example, 1 GO
It is assumed that P is composed of 12 frames and inter-coded frames (P frames) are inserted every two frames. The operation in the normal reproduction will be described below with reference to FIG.

First, when a coded data string of an intra-frame coded frame (I frame) is input as the first data string, intra-frame decoding is performed and the image memory 113
Write in. When an inter-frame coded frame (P frame) is input as the second data string, the I-frame image stored in the image memory 113 is output to the output switching unit 110, and the I-frame image is displayed. Interframe decoding is performed using the data, and the decoding result is written in the image memory 114.

When the data of the frame interpolation coded frame (B frame) is input as the third data string, the image of the I frame stored in the image memory 113 and the P frame stored in the image memory 114. And the inter-frame decoding is performed using the image and the decoding result is output to the output switching unit 110. Similarly, in the case of the fourth data string, inter-frame decoding is performed using the I-frame image stored in the image memory 113 and the P-frame image stored in the image memory 114 to perform decoding. The result is output to the output switching unit 110.

In the P frame input as the fifth data string, the P frame image stored in the image memory 114 is output to the output switching section 110, and the P frame image is used to perform interframe decoding. Then, the decryption result is written in the image memory 115. In the sixth and seventh B frames, interframe decoding is performed using the P frame image stored in the image memory 114 and the P frame image stored in the image memory 115, and the decoding result is obtained. Output to the output switching unit 110.

In the eighth P frame, the image memory 1
The P frame image stored in 15 is output to the output switching unit 110, interframe decoding is performed using the P frame image, and the decoding result is written to the image memory 116. Then, in the ninth and tenth B frames, interframe decoding is performed using the P frame in the image memory 115 and the P frame in the image memory 116, and the decoding result is output to the output switching unit 110. To do.

Similarly, for the data of the next GOP, the decoding results of the I frame and P frame are written in the image memories 113 to 116, read out after 3 frames and output to the output switching unit 110, and the B frame is output. The decoding result of is output to the output switching unit 110 as it is. Here, the output switching unit 110
In the case of normal reproduction, it is controlled so that the signal from the image decoding processing unit 109 is always output.

Next, the operation for performing reverse reproduction will be described with reference to FIG. First, the system controller 111 controls the feed control unit 106 so that the GOP units are reproduced in reverse order. The reproduced signal is shown in Fig. 4.
It is supplied to the image decoding processing unit 109 in such an order.
That is, when the nth GOP is played, the next (n-1) th GOP, then the (n-2) th GOP, and so on. , Play in the same order as normal.

First, the nth (third in FIG. 4) G
The first data string of OP is input and the image of the I frame is intra-frame decoded and written in the image memory 113. The decoding process is not performed for the data strings of the second to third B frames, and when the data string of the fourth P frame is input, the already decoded I frame of the image memory 113 is deleted. The data is decoded and written in the image memory 114. The data strings of the 5th and 6th, 8th and 9th, and 11th and 12th B frames are ignored, and the data strings of the 7th and 10th P frames are Image memories 114 and 115
It is decoded using the decoded P frame data stored in, and written in the image memories 115 and 116, respectively.

Next, when the first data string of the (n-1) th (second in FIG. 5) GOP is input, I
The frame data is decoded and written in the image memory 117, and the image stored in the image memory 116 is output. At this time, the output switching unit 110 is controlled to output the signal from the image decoding processing unit 109. In the next frame, the decoding process of the B frame is not performed, and the image interpolation processing unit 112 performs the interpolation process of the image memory 115 and the image memory 116 and supplies the interpolated image to the output switching unit 110. Then, the output switching unit 11
0 is controlled by the system controller 111 to output a signal from the image interpolation processing unit 112. Similarly, in the next frame, the decoding processing of the B frame is not performed, and the output of the image interpolation processing unit 112 is the output switching unit 1.
It is output via 10.

In the same manner, the signal shown in FIG. 4 is output. That is, the I frame and the P frame are once stored in the image memory and output, and for the B frame, the result of interpolating the image stored in the image memory is output instead of the decoding process.

Here, the operation of the image interpolation processing unit 112 will be described in a little more detail. For example, image memory 1
When the decoded image stored in 15 and the decoded image stored in the image memory 116 are interpolated, for example, the first field is read from the image memory 115 and the second field is read from the image memory 116. Read it. By doing so, it is possible to perform image interpolation processing with an extremely simple configuration. Further, the image stored in the image memory 115 and the image stored in the image memory 116 may be averaged for each pixel and output.

Here, the case where the image in the image memory 115 and the image in the image memory 116 are interpolated has been taken as an example, but the same applies even if any two of the image memories 113 to 117 are selected. Further, an interpolation method of taking a weighted average depending on the position of the output frame may be used. That is, for example, when the number of frames that output the result of the interpolation processing is two, a weight of 2 is given to the decoded image stored in the image memory, whichever is closer in time. , A weighted average is obtained by assigning a weight of 1 to a decoded image that is distant in time.

In this embodiment, control is performed so that an interpolated image is output by the image interpolating process instead of performing the B frame decoding process at the time of backward reproduction.
It is also possible to reproduce the frame. For example GOP
A case in which P is composed of 6 frames and P frames are inserted every two frames will be described with reference to FIG.

When the n-th (fifth in FIG. 5) GOP data string is reproduced, the decoded image of the I frame is written to the image memory 113, and the decoding process is not performed for the next two B frames. , The decoded image of the next P frame is written in the image memory 114. Next, when the data sequence of B frame is input, I stored in the image memory 113 is input.
Decoding processing is performed using the image of the frame and the image of the P frame stored in the image memory 114, and writing is performed in the image memory 115. The next B frame is similarly written in the image memory 116.

Subsequently, the (n-1) th (4th in FIG. 5)
When the data string of the (th) GOP is reproduced, the decoded image of the I frame is written to the image memory 117, and the decoded image of the P frame of the image memory 114 is output.
Output via 10. In the next two frames, the decoded image of the B frame stored in the image memory 116,
The decoded images of the B frame stored in the image memory 115 are sequentially output via the output switching unit 110. Then, the decoded image of the I frame stored in the image memory 113, the image memory 113, and the image memory 11
The interpolated image of No. 4 is output in this order. In this way, at the time of backward reproduction, it is possible to perform decoding processing for some B frames and output interpolated images for the remaining B frames instead of performing decoding processing.

Further, in the present embodiment, the number of image memories is set to 5 (for 5 frames), but the number of image memories is not limited to this. For example, GOP is composed of 6 frames and P frames are arranged every 2 frames. When there is no B frame playback when the image is inserted into the
Frame) is good. The reverse reproduction operation in this case will be briefly described with reference to FIG.

When the n-th (5th in FIG. 6) GOP is reproduced, the decoded image of the I-frame becomes the image memory 113.
Then, the decoded image of the P frame is stored in the image memory 114. Then, when the (n-1) th (4th in FIG. 6) GOP is reproduced, the decoded image of the I frame is written to the image memory 115, and the image of the P frame of the image memory 114 is output to the output switching unit 110. Output via. In the next two frames, the interpolated image of the image memory 113 and the image memory 114, which is created by the image interpolation processing unit 112, is output via the output switching unit 110. Similarly, the I frame and the P frame are written in the image memory and then read out, and the interpolated image is output instead of the B frame. ) Shows that it is good.

As described above, according to this embodiment, when performing backward reproduction, a part or all of the B frame is
Instead of performing the decoding process, the image already decoded and stored in the image memory is controlled to be interpolated and output, so that the backward reproduction function can be realized with a simple configuration.

FIG. 7 is a block diagram of a video signal decoding / reproducing apparatus according to the second embodiment of the present invention.
In FIG. 7, 701 is a video disk, 702 is a spindle motor, 703 is a rotation control unit, 704 is a pickup, 705 is a feed motor, 706 is a feed control unit, and 70.
7 is a focus / tracking control unit, 708 is a signal processing unit, 709 is an image decoding processing unit, 710 is a rearrangement processing unit, 711 is a system controller, 712 and 71.
3 is an image memory, and 714 is an output switching unit.

The operation of the video signal decoding / reproducing apparatus of the present embodiment having the above-mentioned structure will be described below.
First, the rotation control unit 703 controls the spindle motor 702.
Are controlled, and the video disc 701 rotates at a predetermined rotation speed. In response to a command from the system controller 711, the feed control unit 706 controls the feed motor 705 to move the pickup 704 to a position to be reproduced, and the focus / tracking control unit 707 controls focus and tracking. Also, pickup 7
The reproduced signal from 04 is subjected to processing such as amplification, waveform shaping, clock reproduction, data demodulation, error correction, etc. in the signal processing unit 708, and is supplied to the image decoding processing unit 709 as a data string.

FIG. 8 exemplifies a case where 1 GOP is composed of 12 frames and P frames are inserted every two frames, and a data string and image memories 712 and 713 input to the image decoding processing unit 709 during normal reproduction. It shows an example of the contents of. First, when the encoded data sequence of the I frame is input as the first data sequence, intraframe decoding is performed and the data is written in the image memory 712. When a P frame is input as the second data string, a decoded image of the I frame stored in the image memory 712 is output and interframe decoding is performed using the decoded image of the I frame. , The decoding result in the image memory 71
Write to 3.

When the B frame data is input as the third data string, the I frame decoded image stored in the image memory 712 and the P frame decoded image stored in the image memory 713 are displayed. Inter-frame decoding is performed using the data and the decoding result is output. Similarly, in the case of the fourth data string, inter-frame decoding is performed using the I-frame decoded image stored in the image memory 712 and the P-frame decoded image stored in the image memory 713. And outputs the decryption result.

In the P frame input as the fifth data string, the decoded image of the P frame stored in the image memory 713 is output, and inter-frame decoding is performed using the image of the P frame. , The decoding result is written in the image memory 712. In the sixth and seventh B frames, interframe decoding is performed using the P frame decoded image stored in the image memory 712 and the P frame decoded image stored in the image memory 713. , Outputs the decryption result.

In the eighth P frame, the image memory 71
The decoded image of the P frame stored in 2 is output, the inter-frame decoding is performed using the image of the P frame, and the decoding result is written in the image memory 713. Similarly, the I frame and the P frame are decoded and written in the image memories 712 and 713, and output 3 frames later, and the B frame is output simultaneously with the decoding. The output from the image decoding processing unit 710 is supplied to the rearrangement processing unit 710 and the output switching unit 714. The output switching unit 714 always outputs the signal from the image decoding processing unit 709 during normal reproduction. Controlled as. Therefore, during normal reproduction, the sorting processing unit 7
Since the output signal from 10 is not used, the operation of the rearrangement processing unit may be stopped.

Next, the operation when performing reverse reproduction will be described. First, the GOP immediately before the GOP to be reproduced by the system controller 711 to 2 GOP
The feed control unit 706 is controlled so as to reproduce in units.
That is, as shown in FIG. 9, first the (n-1) th GOP
And the nth GOP is played, and then the (n-2) th GO
Playback is performed by playing back the P and (n-1) th GOP. At this time, the feed motor 705 is controlled by the feed control unit 706 in order to reproduce the (n-1) th GOP and the nth GOP and then reproduce the next (n-2) th GOP. The time until the pickup 704 reproduces the head of the (n-2) th GOP is the pickup access period 901 in FIG. On the other hand, from the system controller 711 to the rotation control unit 703,
It is instructed to make the rotation speed of the spindle motor 702, for example, 2.5 times as high as that in the normal reproduction. This magnification is 2
A value is selected such that the sum of the reproduction time of the GOP data and the worst value of the pickup access time 901 is less than or equal to the reproduction time of the image of 1 GOP.

The signal reproduced in this way is shown in FIG.
It is supplied to the image decoding processing unit 709 in the order of 0. First, the reproduction of the (n-1) th and nth GOPs will be described with reference to FIG. 10 for the case of n = 4.

In the (n-1) th GOP, only I frame and P frame are decoded, and B frame is not decoded. Further, the (n-1) th GOP does not output the decoded image. As a result, as shown in FIG. 10, the decoding results of the I frame and the P frame are written in the image memories 712 and 713. In the subsequent nth GOP, all frames are decoded. That is, when the encoded data sequence of the I frame is input as the first data sequence, intraframe decoding is performed and the decoding result is displayed in the image memory 7.
Write to 12.

As the second and third data strings, B
When the encoded data of the frame is input, the image memory 7
Interframe decoding is performed using the I-frame decoded image stored in 12 and the P-frame decoded image stored in the image memory 713, and the decoding result is output. Fourth
When the P-frame encoded data is input as the th data string, the I-frame decoded image stored in the image memory 712 is output, and the I-frame decoded image is used to perform inter-frame decoding. And the decoding result is written in the image memory 713. When B frame data is input as the fifth and sixth data strings, the I frame decoded image stored in the image memory 712 and the P frame decoded image stored in the image memory 713 are displayed. Inter-frame decoding is performed using the data and the decoding result is output.

Similarly, the decoding result of the P frame is written in the image memory 712 or 713 and output after three frames, and the decoding result of the B frame is output as it is. In this way, the (n-1) th and nth GOPs are reproduced in the time of 1 GOP, and the decoded image of the nth GOP is output. Similarly, next, the (n-2) th and (n
-1) th GOP, and (n-3) th and (n-)
2) Playback is performed as the second GOP.

The output signal of the image decoding processing unit 709 is supplied to the rearrangement processing unit 710 and the output switching unit 714. During reverse reproduction, the output switching unit 714 always outputs the signal from the rearrangement processing unit 710. Is controlled and output. The rearrangement processing unit 710 performs processing for rearranging the input images so that the order is reversed on a frame-by-frame basis. Therefore, at the time of backward reproduction, the image output from the image decoding processing unit 709 is the rearrangement processing unit 71.
The order of the frames is rearranged in the reverse order by 0, and the frames are output through the output switching unit 714.

As described above, according to this embodiment, in order to reproduce the image of the n-th GOP at the time of backward reproduction (n-
1) Since it controls to play from the GOP,
All frames can be decoded, and high-quality reverse reproduction is possible.

FIG. 11 is a block diagram of a video signal coding apparatus according to the third embodiment of the present invention. In FIG. 11, 1101 is a rearrangement processing unit, 1102 is an intra-frame encoding processing unit that performs intra-frame encoding, and 11
03 is a forward predictive coding processing unit that performs inter-frame coding by referencing only the temporally previous frame;
A bidirectional predictive coding processing unit 1105 that performs coding using both temporally preceding and subsequent frames, and a backward predictive coding process that performs interframe coding by referring to only temporally subsequent frames. Section, 1106 is an output switching section, 11
Reference numeral 07 is an encoding control unit.

The operation of the video signal coding apparatus of the present embodiment having the above-described structure will be described by taking as an example the case where 1 GOP is composed of 12 frames and P frames are inserted every two frames. First, when the video signal 1108 is input, it is rearranged in the encoding order by the rearrangement processing unit 1101, and the order is as shown in FIG. Then, the image signal from the rearrangement processing unit 1101 is input to the encoding processing units 1102 to 1105, and the encoding control unit 11
The following is controlled by 07.

Next, in the first GOP, the encoding processing units 1102 to 1104 are used to perform the same encoding processing as the conventional one. That is, first, the 0th frame is intraframe-encoded by the intraframe encoding processing unit 1102, and the third frame is interframe-encoded using the 0th frame by the forward prediction encoding processing unit 1103. And the first frame and the second
For the frame, the bidirectional predictive coding processing unit 1104
Interframe coding is performed using the frame and the third frame. Similarly, the sixth frame and the ninth frame are encoded by the forward predictive coding processing unit 1103, and the fourth and fifth frames and the seventh and eighth frames are coded by the bidirectional predictive coding processing unit 1104.

From the next GOP, the first frame is intra-frame encoded by the intra-frame encoding processing unit 1102, but the next two frames (the tenth frame and the eleventh frame in the second GOP) are Backward prediction encoding processing unit 1
At 105, the I frame (second GOP
Then, the twelfth frame) is used to perform interframe coding. The subsequent P frame and B frame are processed in the same manner as the conventional one. That is, taking the second GOP as an example,
The frame, the 18th frame, and the 21st frame are subjected to interframe predictive coding by the forward predictive coding processing unit 1103, and the 13th, 14th frame, the 16th, 17th frame, and the 19th, 20th frame are bidirectional predictive coding. Processing unit 1104
Interframe predictive coding is performed.

The encoding control is performed by such an encoding control unit 1.
The result of the encoding performed by 107 is supplied to the output switching unit 1106. The output switching unit 1106 is also controlled by the encoding control unit 1107 so as to select the output from the encoding processing units 1102 to 1105 in accordance with the encoding order, and outputs the compressed encoded signal 1109.

In this embodiment, 1 GOP is 1
Although the description has been made by taking the case where two P frames are inserted every two frames as an example, the present invention is not limited to this, and the GOP size and the P frame insertion interval may be arbitrary.

As described above, according to this embodiment, since the inter-coded frame is coded so as not to refer to the image of another GOP, only the data in one GOP is included in it. Since it is possible to decode the frame, the backward reproduction can be realized very easily.

[0057]

As described above, according to the present invention,
When a plurality of frames of an image signal are compressed and recorded as one image unit and reproduced, it is possible to reproduce in the reverse direction, and the practical effect is great.

[Brief description of drawings]

FIG. 1 is a block diagram of a video signal decoding / reproducing apparatus according to a first embodiment of the present invention.

FIG. 2 is a format diagram showing an example of a format of a recording signal.

FIG. 3 is a diagram showing a state in which a decoding result at the time of normal reproduction in FIG. 1 is stored in an image memory.

FIG. 4 is a diagram showing a state in which a decoding result at the time of reverse reproduction is stored in an image memory.

FIG. 5 is a diagram showing a state where a decoding result at the time of reverse reproduction is stored in an image memory.

FIG. 6 is a diagram showing a state in which a decoding result at the time of reverse reproduction is stored in an image memory.

FIG. 7 is a block diagram of a video signal decoding / reproducing apparatus according to a second embodiment of the present invention.

8 is a diagram showing a state in which a decoding result at the time of normal reproduction in FIG. 7 is stored in an image memory.

FIG. 9 is a diagram showing the order of reproduced signals during reverse reproduction.

FIG. 10 is a diagram showing a state in which a decoding result at the time of reverse reproduction is stored in an image memory.

FIG. 11 is a block diagram of a video signal encoding device according to a third embodiment of the present invention.

12 is a diagram showing the operation of FIG.

FIG. 13 (a) is a GO in a conventional compression encoding system.
The figure which shows the frame structure of P. (b) is a figure which shows the encoding order in the conventional compression encoding system.

[Explanation of reference numerals] 101,701 Video disk 102,702 Spindle motor 103,703 Rotation control section 104,704 Pickup 105,705 Feed motor 106,706 Feed control section 107,707 Focus / tracking control section 108,708 Signal processing section 109,709 Image decoding processing unit 110,714,1106 Output switching unit 111,711 System controller 112 Image interpolation processing unit 113 to 117,712,713 Image memory 201 Address information signal 202 Video information signal 710,1101 Rearrangement processing unit 901 Pickup access time 902 Time to reproduce 1 GOP image 1102 Intraframe coding processing unit 1103 Forward prediction coding processing unit 1104 Bidirectional prediction coding processing unit 1105 Rear Predictive encoding unit 1107 encoding control unit

Claims (4)

(57) [Claims] 1. A video signal decoding / reproducing apparatus for reproducing a plurality of continuous frames of a moving image signal as one image unit and reproducing moving image data compressed by predictive coding and recorded on a recording medium. A moving image data reproducing means capable of reproducing the moving image data for each image unit, and a first decoding means for performing in-frame decoding of a reproduced signal reproduced by the moving image data reproducing means, Second decoding means for performing inter-frame decoding using prediction of the reproduction signal from a temporally forward frame; and prediction of the reproduction signal from a temporally forward frame and temporally backward The third decoding means for performing inter-frame decoding using prediction from the frame in the direction and the first decoding means.
The decoded image which has been decoded and the second decoding means.
Store both or one of the decoded images
The decrypted image storage means to be stored and the decrypted image storage means
A predetermined two of the plurality of stored decoded images are stored.
Image interpolating means that obtains an interpolated image using an image, and
At the time of reproduction, one of the images decoded by the third decoding means
Instead of outputting all or all, the image interpolating means
And a means for controlling so as to output an interpolated image . 2. The image interpolating means selects and outputs the first field of the first image stored in the decoded image storing means as the output image of the first field, and outputs it as the output image of the second field. 2. The video signal decoding / reproducing apparatus according to claim 1, further comprising means for selecting and outputting the second field of the second image stored in the decoded image storage means. 3. A video signal decoding / reproducing apparatus for reproducing a plurality of continuous frames of a moving image signal as one image unit and reproducing moving image data compressed by predictive coding and recorded on a recording medium. A moving image data reproducing means capable of reproducing the moving image data for each image unit, and a first decoding means for performing in-frame decoding of a reproduced signal reproduced by the moving image data reproducing means, Second decoding means for performing inter-frame decoding using prediction of the reproduction signal from a temporally forward frame; and prediction of the reproduction signal from a temporally forward frame and temporally backward Third decoding means for performing inter-frame decoding using prediction from a frame in the directional direction, and in the case of decoding the image of the image unit during reproduction in the reverse direction, of the image unit to be reproduced One before A video signal decoding / reproducing apparatus comprising: a unit for controlling the image unit and the image unit to be reproduced so as to be reproduced within a period of time equal to or less than a period for outputting the image of the image unit. . 4. A video signal coding apparatus for compressing a video signal by predictive coding, wherein a plurality of consecutive frames of a moving picture signal are used as one image unit, and a first code for performing intra-frame coding. Second coding means for performing interframe predictive coding by utilizing the correlation between the coding means and the temporally forward frame, and the correlation between the temporally forward frame and the temporal backward direction. Third coding means for performing interframe predictive coding by utilizing both the correlation with the frame and interframe predictive coding by utilizing the correlation with the frame in the temporally backward direction. An encoding means and an image of one frame in the image unit is encoded by the first encoding means,
The second encoding means encodes every n frames (n is a natural number) from the frame, and the n frames before the frame are encoded by the fourth encoding means, and other frames. And a means for controlling an encoding method so that the third encoding means encodes the video signal.