JP2003209801A - Moving picture coding apparatus and moving picture recording / reproducing apparatus - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent an increase in the number of pictures processed until a screen is displayed at the time of random access reproduction, to increase the degree of freedom in connection editing, and to apply to a compression mode other than MPEG. Can be encoded. SOLUTION: Based on information detected by an image switching detecting means (screen switching detecting circuit 3) for detecting whether or not the moving image signal to be encoded is the same as the moving image signal of the immediately preceding or succeeding frame. The encoded data output from the moving image encoding means (the encoding control unit 5) for encoding the moving image signal to generate the encoded moving image data, and the difference 0 encoded data generating means (the difference 0 B and P
One of the encoded data output from the encoded picture data generator 4) is selected.

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 having a function of coding a moving picture signal including a continuous reproduction of the same picture, such as slow reproduction, and a moving picture using the same. The present invention relates to a recording / reproducing device.

[0002]

2. Description of the Related Art In recent years, a moving image signal is encoded by using a well-known moving image compression technique such as MPEG, and a magnetic recording tape, a hard disk, a DVD-RAM.
There have been developed a system for recording moving image coded data on a recording medium such as the above, and a system for performing decoding processing on moving image coded data recorded on a recording medium and reproducing it as a moving image signal.

In such a system, an apparatus having a function of reproducing moving image coded data recorded on a recording medium and transmitting it to another device has been developed. Needs to be transmitted on the transmitting device side after being converted into a moving image coded data format that can be handled by the receiving device side, and a trick is required when performing a trick play state such as search or slow.

For example, a signal recorded on a DVD in an MPEG program stream (hereinafter, referred to as MPEG_PS) format is converted into an MPEG transport stream (hereinafter, referred to as a signal).
Converted to MPEG_TS) format and converted to IEEE13
In a system for transmitting to a set top box (hereinafter, referred to as STB) via 94, in the case of normal reproduction, a technique called transcoding is used to convert MPEG_PS format to MPEG in the encoded state.
Converting to the _TS format is relatively easy. However, at the time of slow reproduction, it is difficult to convert to the MPEG_TS format which can be decoded by the STB decoder having no special mechanism.

Therefore, once the decoded moving image is MPEG_TS so as to be compatible with all reproduction modes.
Although it is an easy solution to add a moving picture coding apparatus capable of coding in a format, the moving picture coding apparatus of MPEG is equipped with a motion compensation predictive coding circuit that requires a large-scale circuit. Therefore, there is a problem that the cost is significantly increased. As an example of a method for solving such a problem, in a moving image re-encoding device that re-encodes a moving image signal obtained by decoding encoded data, a code included in moving image compressed data before decoding A moving image re-encoding device capable of realizing high-quality re-encoding by omitting a motion vector detection circuit required for motion compensation prediction by encoding using a coding parameter is disclosed in
No. 00-244929.

Here, the technique disclosed in Japanese Patent Laid-Open No. 2000-244929 will be specifically described with reference to FIGS. 8 to 10. FIG. 8 is a block diagram showing a configuration of a system including a moving image re-encoding device, FIG. 9 is a block diagram showing an example configuration of a video encoder in the moving image re-encoding device,
FIG. 10 is a schematic diagram showing an operation timing example of the moving image re-encoding device.

In FIG. 8, 110 is a data separation unit, 1
11 is an audio data buffer memory, 112 is a moving image data buffer memory, 113 is a sub-picture data buffer memory, 114 is a navigation data buffer memory, 1
15 is an audio decoder, 116 is a video decoder,
Reference numeral 117 is a sub-video decoder, 118 is a video overlay processing unit, 119 is an addition unit, 120 is a GUI image signal generation unit,
121 is an audio encoder, 122 is a video encoder, 123 is a frame memory, 124 is a re-encoding unit audio data buffer memory, 125 is a re-encoding unit moving image data buffer memory, 126 is a multiplexing unit, 127 is an IE.
EE1394 interface, 128 is a re-encoding unit,
Reference numeral 129 is an audio signal D / A converter, 130 is a video signal D / A converter, 131 is a data memory, and 150 is an optical disk device.

In FIG. 9, 170 is a motion compensator, 17
2 is a motion compensation mode and DCT type determination unit, 173
Is a rate control unit, 174 is a DCT processing unit, 175 is a quantization unit, 176 is an inverse quantization unit, 177 is an inverse DCT processing unit,
Reference numeral 178 is a variable length coding unit.

In FIG. 10, (a) is a decoding timing of moving image coded data, and (b) is a video decoder 11.
6, the decoding timing at the time of 1/3 times slow reproduction, (c) the moving image signal decoded as the 1/3 times slow reproduction, (d) the moving image re-encoding processing timing, (e) Is the re-decoded signal.

The operation of the system including the moving picture re-encoding device having the above configuration will be briefly described. The optical disc device 150 is, for example, of the DVD standard, and audio data, encoded moving image data, sub-picture data, navigation data, etc. are multiplexed and recorded.
The signal reproduced from the optical disk device 150 is input to the data separation unit 110 and separated into each data of audio data 151, moving image data 152, sub-picture data 153, and navigation data 154. The separated data 151, 152, 153, and 154 pass through the buffer memories 111, 112, 113, and 114, respectively, and the audio decoder 115 and the video decoder 11
6. Decoded by the sub-picture decoder 117.

For the moving picture signal 156 obtained by decoding the moving picture data by the video decoder 116, the sub-picture signal 157 obtained by decoding the sub-picture data by the sub-picture decoder 117, and the reproduction apparatus GUI. (Grap
A GUI image signal 159, which is uniquely generated by the user interface image signal generator 120 in response to the user's operation 160, and an image overlay processor (OSD) 1 via an adder 119.
Overlay (composite) processing is performed by 18.

The audio signal 155 obtained by decoding the audio data in the audio decoder 115 and the moving image signal 158 subjected to the overlay processing in the video overlay processing unit 118 are analogized by the D / A converters 129 and 130, respectively. The signals 161 and 162 are converted and output to the outside. Further, the audio signal 155 and the moving image signal 158 after the overlay processing are re-encoded by the audio encoder 121 and the video encoder 122, respectively. The audio data and the moving image data obtained by this re-encoding are buffer memories 124 and 12 respectively.
5, the signal is multiplexed into the transport stream by the multiplexing unit 126, and is further digitally output from the IEEE 1394 interface 127.

Also, from the video decoder 116, the moving image data 15 before decoding such as the motion vector, the coding mode, the quantization step, etc. for each macroblock is simultaneously performed with the decoding.
2 is extracted, and the encoding parameter 164 is temporarily stored in the data memory 131. In the video encoder 122, from the encoding parameter data temporarily stored in the data memory 131,
The coding parameters corresponding to the image frame and macroblock to be recoded are read out and input together with predetermined motion vector information 165 given from the outside.

FIG. 9 shows a configuration example of the video encoder 122 in the moving picture re-encoding device. In addition, in FIG.
The same components as those shown in FIG. 8 are designated by the same reference numerals. The video encoder 122 is based on a motion-compensated predictive orthogonal transform coding system represented by MPEG2 or the like, and as shown in FIG. 9, a motion compensation unit 170, a motion compensation mode (coding mode), and a DCT type determination unit 17
2, DCT processing unit 174, quantization unit 175, inverse quantization unit 176, inverse DCT processing unit 177, frame memory 12
3, a rate control unit 173, and a variable length coding unit 178.

The video encoder 122 is a standard M encoder.
A feature of the present invention is that there is no motion vector detection circuit required in a moving picture coding device such as a PEG2 encoder. A normal moving picture coding apparatus requires a huge amount of block matching calculation in order to detect a motion vector for each macroblock. Generally, the motion vector detection circuit occupies a very high ratio of hardware resources in the entire encoding device, but the video encoder 122 does not require such a motion vector detection unit having a large hardware scale. That is, in this moving image re-encoding device, motion compensation is performed by using both the motion vector information of the encoding parameter 164 extracted from the moving image data 152 before decoding and the predetermined motion vector information 165 given from the outside. I do.

Next, the motion compensation mode and DCT type determination unit 172 determines the motion vector of the encoding parameter 164 from the power or magnitude of the prediction error signal by each motion compensation and the power or magnitude of the image signal to be encoded. It is determined for each macroblock which of the information and the motion vector information 165 is to be used or whether the intra coding is to be performed. Next, for the macroblock for which the predictive coding based on the motion vector information of the coding parameter 164 extracted from the moving image data 152 before decoding is selected, the DCT type described later is extracted from the moving image data 152 before decoding. Match the DCT type
In other cases, optimum DCT type detection is performed.

The rate controller 173 includes a quantizer 175.
The quantization step is determined for each macroblock used in. That is, first, with respect to the macroblock for which the predictive coding based on the motion vector information of the coding parameter 164 extracted from the moving picture data before decoding 152 is selected, if there is no constraint of the output bit rate, the moving picture data 162 When the quantization step extracted from the above is used as it is and the output bit rate is restricted, the quantization step is determined with reference to the generated code amount 180 so that the desired bit rate is obtained. In addition, a macro block for which external predetermined motion vector information 165 is selected,
Alternatively, for a macroblock for which intra-encoding is selected, if the output bit rate is not restricted, a quantization step extracted from the moving image data 152 or a predetermined quantization step is used to output the output bit rate. In the case of being restricted by, the quantization step is determined with reference to the generated code amount 180 so as to obtain a desired bit rate.

In the moving picture re-encoding device configured as described above, the method of performing the slow reproduction processing on the encoded moving picture data input to the video decoder 116 to decode it, and the slow reproduction processing The re-encoding procedure for the performed decoded data will be described in detail. For convenience of explanation, the slow reproduction speed is set to 1/3.

The features of the MPEG encoding / decoding method will be briefly described below. The MPEG encoding is composed of motion compensation prediction, DCT processing, and quantization processing, and is classified into three types of I picture, P picture, and B picture depending on the prediction direction of the time axis, and one I picture and 0 picture. G consisting of the above P picture and B picture
It is performed based on the OP structure. An I picture is an intra-frame coded image, a P picture is an inter-frame predictive coded image predicted from a temporally preceding I picture or a P picture, and a B picture is a temporally subsequent and preceding I picture and P picture, or It is an inter-frame predictive coded image predicted from one of them. Therefore, an I picture that is a prediction source is required to decode a P picture, and an I picture and a P picture that are prediction sources are required to reproduce a B picture.

In FIG. 10, I, B and P indicate the type of each picture, and the numbers following it indicate the display order. For example, I2 picture is predicted from intra-frame coded picture and P5 picture is predicted from I2 picture. Inter-frame predictive coded image, B0 picture, B1 picture are inter-frame predictive coded image predicted from I2 picture, B3 picture, B4 picture are I2 picture and P5
It is an inter-frame predictive coded image predicted from a picture. Therefore, decoding a P5 picture requires an I2 picture, decoding a B0 picture and a B1 picture requires an I2 picture, and decoding a B3 picture and a B4 picture requires an I2 picture and a P6 picture.

When decoding is performed according to the above-described decoding method, the decoding timing of a general MPEG moving image is as shown in FIG. 10 (a). B0 picture, B
One picture cannot be referenced until I2 picture processing is performed, and B3 picture and B4 picture are I2 picture and P picture.
This is because it cannot be referenced until the processing of 5 pictures is performed. When performing slow reproduction at 1/3 times speed, the data of the same frame may be repeatedly displayed three times each.
As shown in 0 (b), even if the MPEG data is received at an interval of 3 frames, it cannot be displayed well by an apparatus equipped with an MPEG decoder having no special device.

Therefore, when the encoded moving image data is subjected to slow reproduction processing and decoding, it is combined at a timing of an integral multiple of the frame period (slow reproduction at 1/3 speed is realized. In the case of 3 times), slow reproduction is realized by repeatedly displaying the same display frame when decoding is not performed, and the decoded moving image signal is
It becomes as shown in FIG. In FIG. 10 (c), the part to which only the numbers are attached is the part where the data of the same frame as the I, P and B pictures to which the same numbers are attached are repeatedly displayed.

On the other hand, in the case of re-encoding the decoded moving image signal shown in FIG. 10 (c) for slow reproduction at 1/3 speed, the re-encoding output is the encoding procedure. In consideration of the structure of inter-frame prediction, re-encoding processing is performed at the timing shown in interval 10 (d). This is because the B0 picture and the B1 picture cannot be processed until the I2 picture is processed because recoding is performed using the coding parameter extracted when the coded data is decoded.

Here, the B0 picture frame and the B1 picture frame are re-encoded by repeating the same moving picture frame as a B picture, and the P2 'picture is re-encoding as a P picture by the same moving picture frame as the I2 picture. Since the reference image and the predicted image match at that time, by performing motion-compensated predictive coding of the zero vector, the prediction error signal is always zero, and coding with extremely high coding efficiency can be performed. It is said to be possible.

[0025]

However, in the method described in the above-mentioned conventional technique, the same picture frame as the I picture is recoded as a P'picture by using motion compensation predictive coding using a zero vector. When converting to P '
The picture difference is obtained as the difference between the moving picture signal of the I picture that has already been re-decoded and the P picture that is the moving picture signal (that is, the I picture before re-encoding).
Even if motion compensation predictive coding using zero vector is performed,
Since the processing by the DCT processing unit 174 and the quantization unit 175 shown in FIG. 9 is performed, an error may occur, and the difference is not always 0. Therefore, the re-decoded P'picture and the re-decoded I picture do not become the same image, and the re-decoded moving image signal becomes as shown in FIG. 10 (e).

Further, the decoding of the moving image data is performed at the timing of an integral multiple of the frame period (three times when the slow reproduction of 1/3 times speed is realized), and the same display frame is repeated when the decoding is not performed. Since it is displayed, the number of pictures that make up the GOP at the time of re-encoding increases by an integral multiple of the frame cycle (three times in the case of re-encoding for slow playback at 1/3 times speed). become.

In this case, there is no problem as long as the re-encoded moving image compressed data is output via IEEE 1394 and decoded and displayed on the receiving side, but the re-encoded moving image compressed data is randomly accessible media. However, the following problems occur when recording on. That is, when random access such as reproduction from the middle of GOP is performed on the re-encoded moving image compressed data, the decoding process of I and P pictures necessary for decoding of B and P pictures is performed. , P2 ′ picture, P5 ′ picture, and the problem becomes more prominent in reverse reproduction and reverse slow reproduction. In addition, when performing a joint editing operation in GOP units, the time required to configure one GOP becomes long, which causes a problem that the degree of freedom decreases.

Further, since the above-mentioned conventional re-encoding method is premised on the use of the encoded parameter extracted when the encoded data is decoded, the moving image code other than MPEG such as the DV system is used. There was a problem that it could not be applied in the case of digitized data.

As described above, in the above-mentioned conventional technique, it is possible to add the moving image re-encoding device at low cost, but there are various problems. On the other hand, commercially available MPEG data reproducing devices include devices that include a circuit for MPEG-encoding an analog input signal from the outside and recording the same. In such an apparatus, a moving image is only used for re-encoding. Since it is not necessary to add an image coding device, it is possible to provide a coding device in which a motion vector detection circuit necessary for motion compensation prediction is mounted.

The present invention has been proposed in view of the above circumstances, and is based on the premise of using an encoding device equipped with a motion vector detection circuit necessary for motion compensation prediction, and a code for processing consecutive identical image frames. In the means of
Until the screen is displayed during random access reproduction by encoding the moving image encoded data so as to maintain the same image display of the image and controlling the GOP configuration according to the switching of the image. A moving picture coding apparatus and a moving picture coding apparatus capable of preventing an increase in the number of processed pictures, increasing the degree of freedom at the time of splicing editing, and performing the same coding for a compression format other than MPEG are used. An object is to provide a moving image recording / reproducing device.

[0031]

A moving picture coding apparatus according to the present invention is a moving picture coding apparatus for coding a moving picture signal, wherein the moving picture signal to be coded is a moving picture of a frame immediately before or immediately after. An image switching detection means for detecting whether or not it is the same as an image signal, a moving picture coding means for coding a moving picture signal to generate moving picture coded data, and a B picture of difference 0. To select difference 0 coded data generation means for generating coded data, coded data output from the moving picture coding means, and coded data output from the difference 0 coded data generation means And the encoded data selecting means, based on the information detected by the image switching detecting means, the encoded data output from the moving image encoding means and the encoded data selecting means. Is characterized in that selects one of the coded data outputted from the frequency 0 encoded data generating means.

The moving picture coding apparatus according to the present invention is
When the moving picture signal to be coded by the coded data selection means is the same as the image of the immediately following frame, a backward prediction B picture code of difference 0 output from the difference 0 coded data generation means. When the encoded image data is selected and the moving image signal to be encoded is different from the image of the immediately following frame, the encoded data output from the moving image encoding means is selected.

The moving picture coding apparatus according to the present invention is
An upper limit of the number of pictures forming the GOP is set, and the number of pictures forming the GOP is variable below the set upper limit value according to the slow reproduction speed of the input moving image signal. .

The moving picture coding apparatus according to the present invention is
In a moving picture coding device for coding a moving picture signal, an image switching detecting means for detecting whether or not the moving picture signal to be coded is the same as the moving picture signal of the immediately preceding or following frame, Moving picture coding means for coding a moving picture signal to generate moving picture coded data; difference 0 coded data generation means for generating coded data of B and P pictures with a difference of 0; Coded data output from the moving image coding means and coded data selection means for selecting the coded data output from the difference 0 coded data generation means are provided, and the coded data selection means comprises: Coded data output from the moving image coding means and coded data output from the difference 0 coded data generation means based on the information detected by the image switching detection means. It is characterized in that selects either.

The moving picture coding apparatus according to the present invention is
Number of pictures constituting GOP and I picture or P
When a cycle in which a picture appears is set, and the coded data selection means has the same moving picture signal as the picture of the frame immediately before or immediately after and the picture is coded as a B picture or a P picture, the difference Of the backward prediction B picture encoded data of the difference 0, the forward prediction B picture encoded data of the difference 0, and the forward prediction P picture encoded data of the difference 0 output from the 0 encoded data generation means Is selected, and when the moving image signal to be encoded is different from the image of the immediately following frame, the encoded data output from the moving image encoding means is selected.

The moving picture coding apparatus according to the present invention is
The image switching detection unit compares the moving image signal accumulated in the buffer memory for encoding by the moving image encoding unit with the input moving image signal, thereby obtaining the moving image of the frame immediately before or immediately after. It is characterized by detecting whether or not it is the same as the signal.

The moving picture coding apparatus according to the present invention is
The image switching detection means refers to switching information of a moving image signal supplied from the outside to detect whether the input moving image signal is the same as the moving image signal of the immediately preceding or following frame. It is characterized by.

A moving picture recording / reproducing apparatus according to the present invention is a moving picture recording / reproducing apparatus for recording / reproducing coded data obtained by coding a moving picture signal, wherein the moving picture coding apparatus and the moving picture code are used. Recording medium for recording / reproducing encoded data and moving image decoding means for decoding encoded data, wherein the moving image is reproduced when slow reproduction or still reproduction of a signal recorded on the recording medium is performed. The image decoding means generates switching information as to whether or not the decoded moving image signal is the same as the moving image signal of the frame immediately before or immediately after, and the image switching detecting means in the moving image encoding device causes It is characterized by detecting whether or not it is the same as the moving image signal of the immediately preceding or following frame by referring to the switching information.

The moving picture recording / reproducing apparatus according to the present invention is a moving picture recording / reproducing apparatus for recording / reproducing coded data obtained by coding a moving picture signal, wherein the moving picture coding apparatus and the moving picture code are used. A recording medium for recording and reproducing encoded data, and a moving image decoding means for decoding moving image encoded data supplied from an external device, when the external device performs slow reproduction or still reproduction, Switching information indicating whether or not the moving image signal decoded by the moving image decoding means based on the screen switching information added to the moving image encoded data is the same as the moving image signal of the immediately preceding or following frame. It is generated and is checked by the image switching detection means in the moving image encoding device whether or not it is the same as the moving image signal of the immediately preceding or following frame by referring to the switching information. And it is characterized in that out.

With the above configuration, when processing an image in which the same moving image frame continues such as slow reproduction, backward prediction B picture encoded data with a difference of 0 or difference 0 with a difference of 0 is obtained. Realize the same image display even when moving image compressed data is decoded by selecting and using B-picture coded data of forward prediction or P-picture coded data of forward prediction with a difference of 0 can do. Furthermore, by controlling the GOP configuration according to the user's intention, it is possible to prevent an increase in the number of pictures to be processed until the screen is displayed at the time of random access reproduction, and it is possible to increase the degree of freedom during splicing editing. . The same encoding method can be applied to compression methods other than MPEG. In addition, GOP means Group Of Pictures.

[0041]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a moving picture coding apparatus according to the present invention will be described below with reference to the drawings.

<Video Coding Device> FIGS. 1 to 5 show a video coding device according to an embodiment of the present invention, and FIG. 1 is a block diagram showing a system configuration including the video coding device. FIG. 2 is a schematic diagram showing an example of moving image coding operation timing for 1/3 speed slow reproduction, and FIG. 3 is 1/5.
FIG. 4 is a schematic diagram showing an example of moving image encoding operation timing for double speed slow reproduction, and FIG. 4 is a schematic diagram showing an example of moving image encoding operation timing for a moving image signal including a portion where normal reproduction shifts to 1/3 times slow reproduction. , FIG. 5 shows 1 /
FIG. 7 is a schematic diagram showing an example of a moving image coding operation timing for a moving image signal including a portion where transition from triple speed slow reproduction to normal reproduction is performed.

In FIG. 1, 1 is a moving image signal input terminal,
Reference numeral 2 is a moving image signal storage buffer, 3 is a screen switching detection circuit, 4 is a B and P picture coded data generation unit with a difference of 0, 5 is a coding control unit, 6 is a DCT processing unit, 7 is a quantization unit, Reference numerals 8 and 9 are prediction memories “1” and “2” for storing reference images, 10 is an averaging circuit for interpolative interframe predictive coding of B pictures, and 11 is an inverse quantization unit. Reference numeral 12 is an inverse DCT processing unit, and 13 is a moving image data output terminal.

In FIGS. 2 to 5, (a) of each figure is an input moving image signal, (b) of each figure is encoded data in the encoding order when encoding is performed, each figure (C) is coded data in the display order at the time of decoding when the coding is performed. In addition, “0”, “1”,
A number such as “2” is a number that is updated every time the image is switched. That is, in (a) of each figure, the same number indicates the same image. Also, I0, P1, B2, etc. in (b) and (c) of each figure identify the type of picture at the time of encoding, that is, the identification of the I picture, P picture, B picture, and the corresponding input image. The numbers F and B at the end of B0F and B0B indicate the prediction direction of the B picture, that is, the forward direction (Forw).
ard) and the reverse direction (Backward).

A method of coding a moving picture signal input from the moving picture signal input terminal 1 in the moving picture coding apparatus configured as described above will be specifically described. First, the moving image signal input from the moving image signal input terminal 1 is input to the moving image signal storage buffer 2 and the screen switching detection circuit 3, and in the screen switching detection circuit 3, the input frame image is immediately preceding. It is detected whether it is the same as the frame image.

When the moving image signal shown in FIG. 2A is input, the first picture 0 is the second picture 0 and the second picture 0 is 2.
The 0th picture 0 is judged to be the same image as the 3rd picture 0, and the backward prediction B of the difference 0 between the two pictures is not encoded.
The picture is counted as needed. It is determined that the third picture 0 is not the same image as the next picture 1, and the encoding control unit 5 sets it as an I picture, and the DCT processing unit 6,
Encoded data I that has been encoded by the quantizer 7
0 is output to the moving image data output terminal 13, and the inverse quantization unit 11 and the inverse D output the encoded data I0.
The CT processing unit 12 performs the decoding process, and the prediction memory “1”
Store in 8.

After that, the B and P picture coded data generation unit 4 having the difference 0 reads out B0B, which is B picture coded data, twice as many times as previously counted and outputs it to the moving picture data output terminal 13. Subsequently, it is determined that the first picture 1 is the same image as the second picture 1 and the second picture 1 is the same image as the third picture 1.
It is counted that two backward prediction B pictures with a difference of 0 are required.

It is determined that the third picture 1 is not the same image as the next picture 2, and the third picture 1 is set as a P picture by the encoding control unit 5 and the decoded data of I0 stored in the prediction memory "1" 8 DCT for the difference after motion prediction compensation
The encoded data P1 subjected to the encoding processing in the processing unit 6 and the quantization unit 7 is output to the moving image data output terminal 13, and the inverse quantization unit 1 outputs the encoded data P1.
1. The inverse DCT processing unit 12 performs processing, and stores it in the prediction memory “2” 9. After that, the B and P picture coded data generation unit 4 having the difference of 0 reads B1B, which is the B picture coded data, twice as many times as previously counted and outputs it to the moving picture data output terminal 13.

The encoded data shown in FIG. 2 (b) can be output by repeating the processing of the picture 2 and subsequent pictures in the same procedure and encoding the data. Note that FIG.
The GOP structure of the encoded data shown in (b) is configured so as to circulate in 15 frames, as an example.
Picture 5 is encoded as an I picture.

When the general MPEG decoding apparatus performs the decoding process on the coded data shown in FIG. 2 (b) generated in this way, the display order is as shown in FIG. 2 (c). . In this case, all B pictures such as B0B, B1B, and B2B are encoded data of backward prediction with a difference of 0, and thus the same image can be displayed for three frame periods.

Next, a method of setting the GOP structure will be described. The first method is a method of determining the upper limit of the number of pictures forming a GOP, and the second method is a method of making the number of pictures forming a GOP and the positional relationship among I, P, and B pictures constant.

First, the first method will be described in detail. As an example, the upper limit of the number of pictures forming the GOP is set to 15, and the slow reproduction speed of the input moving image signal is 1/3 times speed, 1/4 times speed, 1/5 times speed, 1/6 times speed, 1/7 times. The device is capable of double speed. At this time, since the upper limit of the number of pictures is 15, a GOP structure with 15 pictures at 1/3 speed and 1/5 times speed, a GOP structure with 12 pictures at 1/4 speed and 1/6 times speed, 1 By adopting a GOP configuration with 14 pictures at / 7 × speed, the above-described coding can be easily applied. In this way, when the slow playback speed is known, the number of pictures forming a GOP is made variable according to the slow playback speed to be less than or equal to the set upper limit value, so that random access or GOP unit stitch editing can be performed. It can be an advantageous GOP configuration.

Next, the second method will be described in detail. As an example, the number of pictures forming a GOP is 15,
The cycle in which the I picture or P picture appears is 3, that is, the B picture inserted between them is 2, and the slow reproduction speed of the input moving image signal is 1/3 times speed.
The device is capable of 1/5 times speed. At 1/3 speed, if the coding method used in this embodiment is applied as it is, the number of pictures forming a GOP can be 15, and the cycle in which an I picture or a P picture appears can be coded as "3". it can. Next, the operation at 1/5 speed will be described with reference to FIG. At ⅕ speed, the cycle of the I picture or P picture and the switching of the screen are not synchronized, so that some ingenuity is required.

When the moving picture signal shown in FIG. 3A is input, the first picture 0 is the second picture 0 immediately after, and the second picture 0 is the third picture 0 immediately after.
Is judged to be the same image, and it is counted that two backward prediction B pictures with a difference of 0 are necessary without encoding. Three
The second picture 0 is the same image as the fourth picture 0, but in order to comply with the GOP structure, the coding control unit 5 forcibly sets it to the I picture, and the DCT processing unit 6 and the quantization unit 7 The encoded data I0 that has been subjected to the encoding process is output to the moving image data output terminal 13, and the inverse quantization unit 11 and the inverse DCT processing unit 1 are applied to the encoded data I0.
The decoding process is performed in 2, and the result is stored in the prediction memory “1” 8.

After that, B0B which is the backward prediction B picture coded data of the difference 0 is read out twice from the B and P picture coded data generation unit 4 of the difference 0, and the moving image data output terminal is read. Output to 13. Subsequently, the fourth picture 0 is the immediately preceding third picture 0.
Then, the fifth picture 0 is judged to be the same image as the immediately preceding fourth picture 0, and it is counted that two forward prediction B pictures with a difference of 0 are required without being coded.

In order to comply with the GOP structure, the next picture 1 is forcibly set to the P picture by the coding control unit 5 and moves with the decoded data of I0 stored in the prediction memory "1" 8. The coded data P1 that has been subjected to the coding processing in the DCT processing unit 6 and the quantization unit 7 with respect to the difference after the prediction compensation is output to the moving image data output terminal 13 and also to the coded data P1. , The inverse quantization unit 11 and the inverse DCT processing unit 12 perform processing, and store in the prediction memory “2” 9.

After that, B0F, which is the B-picture coded data of the difference 0, which is the forward-predicted B-picture coded data of the difference 0, is read twice for the previously counted number, and the moving image data output terminal is read. Output to 13. Subsequently, the second picture 1 is the immediately preceding first picture 1.
Then, the third picture 1 is determined to be the same image as the immediately preceding second picture 1, and it is counted that two forward prediction B pictures with a difference of 0 are required without being coded.

The fourth picture 1 is forcibly set to the P picture by the coding control unit 5 in order to comply with the GOP structure. However, since the fourth picture 1 is the same image as the first picture 1 coded immediately before as a P picture, predictive coding is not performed, and B and P with a difference of 0 are used.
The P-picture coded data P1 ′ having a difference of 0 is read from the picture-coded data generation unit 4 and output to the moving image data output terminal 13.

After that, B1F, which is B-picture coded data for forward prediction with a difference of 0, is read twice for the previously counted number, and is output to the moving image data output terminal 13. Subsequently, the fifth picture 1 is judged to be the same image as the immediately preceding fourth picture 1, and it is counted that one forward-direction B picture with a difference of 0 is required without being coded.

The first picture 2 is judged to be the same image as the immediately following second picture 2, and it is counted that one backward prediction B picture with a difference of 0 is required without being coded. The second picture 2 is forcibly set to the P picture by the coding control unit 5 in order to comply with the GOP structure,
Coded data P2 obtained by performing coding processing in the DCT processing unit 6 and the quantization unit 7 on the difference after motion prediction compensation with the decoded data of P1 stored in the prediction memory “2” 9
Is output to the moving image data output terminal 13,
Inverse quantizer 11, inverse DCT for encoded data P1
Processing is performed by the processing unit 12 and stored in the prediction memory “1” 8.

Thereafter, the B and P picture coded data generation unit 4 with a difference of 0 counts the forward predicted B picture coded data B1F once, and the backward predicted B picture code with a difference of 0 is once. B2B, which is the converted data, is read out once for the counted time, and the moving image data output terminal 1 is read.
Output to 3. Then, the third picture 2 is the previous 2
The 2nd picture 2 and the 4th picture 2 are judged to be the same image as the immediately preceding 3rd picture 2 and are not encoded.
It is counted that two forward-predicted B pictures with a difference of 0 are required.

The fifth picture 2 is forcibly set to the P picture by the coding control unit 5 in order to comply with the GOP structure. However, since the fifth picture 2 is the same image as the second picture 2 coded immediately before as a P picture, predictive coding is not performed, and B and P with a difference of 0 are used.
The forward-predicted P-picture encoded data P2 ′ with a difference of 0 is read from the picture-encoded data generation unit 4 and output to the moving image data output terminal 13. After that, B2F, which is B picture encoded data, is read twice for the time counted previously, and is output to the moving image data output terminal 13.

By encoding in the above procedure, FIG.
The encoded data shown in (b) can be generated. In addition, for the encoded data shown in FIG.
When the decoding process is performed by the PEG decoding device, the display order is as shown in FIG.
As shown in (c). In this case, B0B, B0F,
All B pictures such as B1F, B2B, and B2F have a difference of 0
Encoded data of forward prediction or backward prediction of
Since P1 'and P2' pictures are forward prediction encoded data with a difference of 0, the same image can be displayed for 5 frame periods.

In the present embodiment, the prediction direction is determined for the B picture included between the I or P pictures of the same image, but the prediction direction may be any if the decoding results are the same. For example, P1 picture and P1 '
The B pictures between the pictures are forward-predicted B1F pictures, but it is clear that the decoding results are the same even for backward-predicted B1B pictures.

As described above, I picture or P
Even if the picture cycle and the screen switching are not synchronized, if the input moving image signals are the same, the corresponding decoded images will be the same, and
It is possible to perform coding with the number of pictures making up a GOP and the positional relationship among I, P, and B pictures fixed.

Next, a method for encoding a moving image signal having a transition between normal reproduction and slow reproduction according to the second method of the GOP structure described above will be concretely described with reference to FIGS. 4 and 5. explain.

In FIG. 4, (a) is a moving image signal including a portion where normal reproduction shifts to ⅓ speed slow reproduction, and (b) is a code when encoding is performed by the second method of the GOP structure. Coded data in encoding order, (c) GOP
It is the encoded data in the display order when encoding is performed by the second method of the configuration. In addition, in FIG. 5, (a) is a moving image signal including a portion where 1/3 times slow reproduction is changed to normal reproduction, and (b) is encoding when encoding is performed by the second method of GOP configuration. Encoded data in order,
(C) is the coded data in the display order when coded by the second method of the GOP structure.

First, a moving picture coding method for a moving picture signal including a portion where normal reproduction shifts to ⅓ speed slow reproduction will be described. When the moving image signal shown in FIG. 4A is input, since the picture 0 is not the same as the picture 1 immediately after and the picture 1 is not the same picture 2 immediately after, the code is used in order to comply with the GOP structure. Control unit 5
Is forcibly set to B picture.

The picture 2 is forcibly set to the I picture by the encoding control unit 5 in order to comply with the GOP structure.
The encoded data I2 subjected to the encoding process in the DCT processing unit 6 and the quantization unit 7 is output to the moving image data output terminal 13, and the inverse quantization unit 11 and the inverse DCT are performed on the encoded data I2. The processing unit 12 performs a decoding process and stores it in the prediction memory “1” 8.

Thereafter, for the picture 0 and the picture 1 set in the B picture, the DCT processing unit compares the difference after the motion prediction compensation with the decoded data of I2 stored in the prediction memory “1” 8. 6. The encoded data B0 and B1 subjected to the encoding process in the quantizer 7 are output to the moving image data output terminal 13. Subsequently, since the picture 3 is not the same picture as the picture 4 immediately after it and the picture 4 is not the same picture as the picture 5 immediately after, the coding control unit 5 is forced to set it as a B picture in order to comply with the GOP structure.

The picture 5 is forcibly set to the P picture by the coding control unit 5 in order to comply with the GOP structure.
Coded data P5 obtained by performing coding processing in the DCT processing unit 6 and the quantization unit 7 on the difference after motion prediction compensation with the decoded data of I2 stored in the prediction memory “1” 8
Is output to the moving image data output terminal 13,
Inverse quantizer 11, inverse DCT for encoded data P5
The processing unit 12 performs a decoding process and stores it in the prediction memory “2” 9. After that, for the pictures 3 and 4 set as the B picture, the decoded data of I2 stored in the prediction memory “1” 8 and the decoded data of P5 stored in the prediction memory “2” 9 and their average The encoded data B3 and B4 that have been subjected to the encoding processing in the DCT processing unit 6 and the quantization unit 7 with respect to the difference after the motion prediction compensation of are output to the moving image data output terminal 13.

The first picture 6 is judged to be the same image as the second picture 6 immediately after, and the second picture 6 is judged to be the same image as the third picture 6 immediately after. It is counted that backward-predicted B-pictures are needed. The third picture 6 is forcibly set to the P picture by the encoding control unit 5 in order to comply with the GOP structure,
Coded data P6 obtained by performing coding processing in the DCT processing unit 6 and the quantization unit 7 on the difference after motion prediction compensation with the decoded data of P5 stored in the prediction memory “2” 9
Is output to the moving image data output terminal 13,
Inverse quantizer 11, inverse DCT for encoded data P6
The processing unit 12 performs a decoding process and stores it in the prediction memory “1” 8.

After that, the B and P picture coded data generation unit 4 with a difference of 0 reads B6B, which is the B picture coded data of the backward prediction with a difference of 0, twice for the time counted previously, and outputs the moving picture data output terminal. Output to 13. Then, the first picture 7 is the second picture 7 immediately after it.
Then, the second picture 7 is judged to be the same image as the immediately following third picture 7, and it is counted that two backward prediction B pictures with a difference of 0 are required without being coded.

The third picture 7 is forcibly set to the P picture by the coding control unit 5 in order to comply with the GOP structure, and the decoded data of P6 stored in the prediction memory "1" 8 is used. The encoded data P7 that has been subjected to the encoding process in the DCT processing unit 6 and the quantization unit 7 with respect to the difference after motion prediction compensation is output to the moving image data output terminal 13 and also to the encoded data P7. The inverse quantizer 11,
The inverse DCT processing unit 12 performs a decoding process and stores it in the prediction memory “2” 9. After that, the B and P picture coded data generation unit 4 with a difference of 0 reads B7B, which is the B picture coded data of backward prediction with a difference of 0, twice for the number counted previously and outputs it to the moving image data output terminal 13. To do.

By encoding in the above procedure, FIG.
The encoded data shown in (b) can be generated. In addition, for the encoded data shown in FIG.
When the decoding process is performed by the PEG decoding device, the display order is as shown in FIG.
As shown in (c).

Next, the moving picture coding means for the moving picture signal including the portion where the 1/3 speed slow reproduction is changed to the normal reproduction will be described. When the moving image signal shown in FIG. 5A is input, the first picture 0 is the immediately following second picture 0 and the second picture 0 is the immediately following 3
It is determined that it is the same image as the second picture 0, and it is counted that two backward prediction B pictures with a difference of 0 are necessary without encoding.

The third picture 0 is a code which is forcibly set to the I picture by the coding control unit 5 in order to comply with the GOP structure and which has been subjected to the coding process in the DCT processing unit 6 and the quantizing unit 7. The encoded data I0 is output to the moving image data output terminal 13, and the encoded data I0 is decoded by the inverse quantization unit 11 and the inverse DCT processing unit 12 to the prediction memory “1” 8. Store.

Thereafter, B0B, which is the B-picture coded data of the difference 0 and backward-predicted B-picture coded data of the difference 0, is read twice for the previously counted number, and the moving image data output terminal is read. Output to 13. Subsequently, the first picture 1 is the immediately following second picture 1.
Then, the second picture 1 is judged to be the same image as the immediately following third picture 1, and it is counted that two backward prediction B pictures with a difference of 0 are required without being coded.

The third picture 1, which is forcibly set to the P picture by the coding control unit 5 in order to comply with the GOP structure, and the decoded data of I0 stored in the prediction memory "1" 8 The encoded data P1 that has been subjected to the encoding processing in the DCT processing unit 6 and the quantization unit 7 with respect to the difference after the motion prediction compensation is output to the moving image data output terminal 13 and also to the encoded data P1. The inverse quantizer 11,
The inverse DCT processing unit 12 performs a decoding process and stores it in the prediction memory “2” 9.

Thereafter, B1B, which is the backward-predicted B-picture encoded data with a difference of 0, is read from the B- and P-picture encoded data generator 4 with a difference of 0 twice, and the moving image data output terminal is read. Output to 13. Next, the first picture 2 is the second picture 2 immediately after it.
Then, the second picture 2 is judged to be the same image as the immediately following third picture 2, and it is counted that two backward prediction B pictures with a difference of 0 are required without being coded.

In order to comply with the GOP structure, the third picture 2 is forcibly set to the P picture by the coding control unit 5 and is decoded with the P1 decoded data stored in the prediction memory “2” 9. The encoded data P2 that has been subjected to the encoding processing in the DCT processing unit 6 and the quantization unit 7 with respect to the difference after the motion prediction compensation is output to the moving image data output terminal 13 and also to the encoded data P2. The inverse quantizer 11,
The inverse DCT processing unit 12 performs a decoding process and stores it in the prediction memory “1” 8. After that, the B and P picture coded data generation unit 4 with a difference of 0 reads B2B, which is the B picture coded data of backward prediction with a difference of 0, twice for the previously counted number and outputs it to the moving image data output terminal 13. To do.

Picture 3 is not the same as picture 4 immediately after, and picture 4 is not the same as picture 5 immediately after, so GO
In order to comply with the P configuration, the encoding control unit 5 forces the B
Set to picture. The picture 5 is forcibly set to the P picture by the encoding control unit 5 in order to comply with the GOP structure, and the difference after the motion prediction compensation with the decoded data of P2 stored in the prediction memory “1” 8 On the other hand, the encoded data P5 subjected to the encoding process in the DCT processing unit 6 and the quantization unit 7 is output to the moving image data output terminal 13, and the inverse quantization unit for the encoded data P5. 1
1. The inverse DCT processing unit 12 performs a decoding process and stores it in the prediction memory “2” 9.

After that, for the pictures 3 and 4 set as the B picture, the decoded data stored in the prediction memory “1” 8 and the P stored in the prediction memory “2” 9
The coded data B3 and B4, which have been subjected to the coding processing in the DCT processing unit 6 and the quantization unit 7 with respect to the decoded data of 5 and the difference after the motion prediction compensation with respect to the average thereof, are the moving image data output terminals 13. Is output to. Next, since the picture 6 is not the same picture as the picture 7 immediately after, and the picture 7 is not the same picture as the picture 8 immediately after, in order to comply with the GOP configuration,
The encoding control unit 5 compulsorily sets the B picture.

The picture 8 is forcibly set to the P picture by the coding control unit 5 in order to comply with the GOP structure.
Coded data P8 obtained by performing coding processing in the DCT processing unit 6 and the quantization unit 7 on the difference after motion prediction compensation with the decoded data of P5 stored in the prediction memory “2” 9
Is output to the moving image data output terminal 13,
Inverse quantizer 11, inverse DCT for encoded data P8
The processing unit 12 performs a decoding process and stores it in the prediction memory “1” 8.

After that, for the pictures 6 and 7 set as the B picture, the decoded data of P8 stored in the prediction memory “1” 8 and the decoded data of P5 stored in the prediction memory “2” 9 and The coded data B6 and B7 that have been subjected to the coding processing in the DCT processing unit 6 and the quantization unit 7 with respect to the difference after the motion prediction compensation with respect to the average are output to the moving image data output terminal 13.

By encoding in the above procedure, FIG.
The encoded data shown in (b) can be generated. In addition, for the encoded data shown in FIG.
When the decoding process is performed by the PEG decoding device, the display order is as shown in FIG.
As shown in (c). In this way, even if the reproduction mode changes in the middle of the GOP structure, it can be applied to the moving picture coding apparatus according to the present embodiment.

<Motion picture recording / reproducing apparatus> Next, FIG. 6 and FIG.
A moving image recording / reproducing apparatus using the moving image encoding apparatus according to the present invention will be described with reference to FIG. 6 and 7 show a moving picture recording / reproducing apparatus using the moving picture coding apparatus according to the present invention. FIG. 6 is an example applied during slow reproduction of a disc recording / reproducing apparatus, and FIG. An example of the configuration in the case where an input signal is decoded, MPEG encoded again, and recorded and reproduced is shown.

In FIG. 6, 21 is a moving image signal input terminal, 22 is a moving image input signal selector, 23 is the MPEG encoding unit described in the above embodiment, 24 is an MPEG decoding unit, and 25 is recording on media. Reproduction signal processing unit, 26
Is an IEEE 1394 terminal for transmitting / receiving encoded data, 27 is a recording medium, 28 is a system controller that controls the entire recording / reproducing apparatus, and 29 is a moving image data output terminal. Further, in FIG. 7, since the same blocks as those in FIG. 6 are denoted by the same reference numerals, only the added blocks will be described. 30 decodes a DV compressed signal input via the IEEE 1394 terminal 26. The DV decoding unit 31 is a moving image output signal selector.

In the moving picture recording / reproducing apparatus configured as described above, a method of recording a moving picture signal input from the moving picture signal input terminal 21, a slow reproduction of coded data recorded on the recording medium 27, and a second reproduction A method of MPEG-encoding and outputting from the IEEE 1394 terminal 26, IEEE
A method of decoding the DV compressed signal input from the 1394 terminal 26, re-encoding it into MPEG, and recording it on the recording medium 27 will be specifically described. The DV compressed signal means "HD DIGITAL VCR CONFE
RENCE ", mainly for consumer digital VCR
It is a compressed signal used in.

First, a method of recording a moving image signal input from the moving image signal input terminal 21 will be described assuming that the recording medium 27 is a DVD. The moving image signal input from the moving image signal input terminal 21 is supplied to the MPEG encoding unit 23 via the moving image input signal selector 22. The MPEG encoding unit 23 encodes the input moving image signal in the MPEG_PS format, which is the recording format of DVD, and supplies it to the recording / reproducing signal processing unit 25. The recording / reproducing signal processing unit 25 performs error correction encoding for adding a parity for correcting an error that may occur at the time of reproduction or digital modulation processing to the encoded data, and records it on the recording medium 27. To do.

Next, a method of MPEG-encoding again and outputting from the IEEE 1394 terminal 26 in the case of slow reproduction of the encoded data recorded on the recording medium 27 in this way will be described. The signal reproduced from the recording medium 27 is digitally demodulated by the recording / reproduction signal processing unit 25, and if there is an error during reproduction, correction processing is performed to reconstruct the original encoded data. The encoded data reproduced in this way is supplied to the MPEG decoding unit 24 based on an instruction from the system controller 28, and MPEG decoding processing is performed to restore the moving image signal.

At the time of 1/3 speed slow reproduction, MPEG
The decoding unit 24 outputs the same moving image signal three times to output a moving image signal as shown in FIG. 2A, and notifies the system controller 28 of the screen switching timing. The moving picture signal is output from the moving picture data output terminal 29 to an external device, and is also transmitted via the moving picture input signal selector 22 to the MPEG encoding unit 23.
Is supplied to. The MPEG encoding unit 23 refers to the screen switching timing supplied from the system controller 28 to detect the screen switching, and uses the method described in the above embodiment to input the input moving image signal. Is MPEG-encoded to generate encoded data as shown in FIG.

Since the format of the MPEG stream that can be input / output through the IEEE 1394 terminal 26 is defined as the MPEG_TS format, it is converted into the MPEG_TS format and output from the IEEE 1394 terminal 26 here. In this way, the MPEG_TS format signal output from the IEEE 1394 terminal 26 is transferred to the IE (not shown).
By receiving and decoding by the receiving device provided with the EE1394 terminal 26, the moving image signal obtained by slow reproduction of the moving image recording / reproducing device according to the present embodiment can be reproduced on the receiving device side. In the present embodiment, MP
The data encoded by the EG encoding unit 23 is transferred to the IEEE 13
Although the example of outputting through the 94 terminal 26 is used, it may be recorded in another position of the recording medium 27 or another recording medium (not shown).

<Recording Method on Recording Medium> Next, IE
A method of decoding the DV compressed signal input from the EE1394 terminal 26, re-encoding it into MPEG, and recording it on the recording medium 27 will be described.

From a DV recording / reproducing apparatus (not shown), IEEE
The DV compressed signal input via the E1394 terminal 26 is supplied to the DV decoding unit 30. DV decoding unit 30
Then, the DV compressed signal is decoded to restore the moving image signal. Here, when the DV recording / reproducing apparatus performs slow reproduction at 1/3 times speed, the DV compressed signal uses only intra-frame encoding, unlike MPEG,
The same DV compressed signal is input every three frames. Furthermore, in the additional information called VAUX data transmitted at the same time, FC (Frame Change Fla) is added.
Since the current frame g) includes an identifier indicating whether or not the current frame is the same as the previous frame, the DV decoding unit 30 decodes the input DV compressed signal as it is and outputs it. A moving image signal as shown in (a) is output and the screen switching timing obtained by referring to the identifier FC is transmitted to the system controller 28.

The moving image signal is output from the moving image data output terminal 29 to an external device via the moving image output signal selector 31, and at the same time, the moving image input signal selector 22.
Is supplied to the MPEG encoding unit 23 via. MPE
The G encoding unit 23 refers to the screen switching timing supplied from the system controller 28 to detect the screen switching, and MPEG-encodes the moving image signal using the above-described method, and then, as shown in FIG. Generate encoded data as shown. The recording / reproducing signal processing unit 25 performs error correction encoding for adding a parity for correcting an error that may occur during reproduction to the encoded data, and
A digital modulation process is performed and the result is recorded in the recording medium 27.

In this way, even when the DV recording / reproducing apparatus is slow-reproducing, the IEEE1394 terminal 26
The input DV compressed signal is decoded via
It can be EG encoded and recorded on the recording medium 27. In the present embodiment, the example in which the data encoded by the MPEG encoding unit 23 is recorded in the recording medium 27 is used, but the data may be output via the IEEE 1394 terminal 26.

As described above, by applying the moving picture coding apparatus according to the present invention to the moving picture recording / reproducing apparatus, the MPEG coding is performed when the same picture is input during slow reproduction or still reproduction. Screen switching detection inside the moving picture coding device by performing the screen switching detection according to an instruction from the system controller with reference to the internal reproduction mode and the additional information supplied from the outside. The circuit can be omitted.

[0099]

The moving picture coding apparatus according to the present invention, when coding the same picture signal in slow reproduction or the like, codes the coded data of a B picture with a difference of 0 and the normal coded data. The coded data is generated by appropriately combining them. Therefore, when the encoded data is decoded, the images that were the same image before the encoding can be decoded as the completely same image.

The moving picture coding apparatus according to the present invention is
The number of pictures forming a GOP is made variable below a set upper limit, and coded data of P or B pictures with a difference of 0 and normal coded data are appropriately combined to generate coded data. Further, the moving picture coding apparatus according to the present invention sets the number of pictures forming a GOP and the cycle in which an I picture or a P picture appears, and selects an I picture, a P picture, or a B picture so as to match the setting. In addition, the number of pictures forming a GOP is made variable below a set upper limit value, and coded data of P or B pictures with a difference of 0 and normal coded data are appropriately combined to generate coded data. Therefore, when the encoded data is decoded, the images that are the same image before encoding can be decoded as the completely same image, and the GOP configuration is advantageous for random access and joint editing in GOP units. be able to.

Further, the moving picture coding apparatus according to the present invention is
By comparing the moving image signal accumulated in the buffer memory for encoding by the moving image encoding means with the input moving image signal, it is determined whether the moving image signal is the same as the moving image signal of the immediately preceding or following frame. To detect. Therefore, the above-described coding method can be applied to any input signal.

The moving picture coding apparatus according to the present invention is
By referring to the switching information of the moving image signal supplied from the outside, it is detected whether or not the input moving image signal is the same as the moving image signal of the immediately preceding or succeeding frame. Therefore, the processing in the image switching detecting means can be reduced.

The moving picture recording / reproducing apparatus according to the present invention refers to the moving picture signal switching information generated by the moving picture decoding means, and refers to the moving picture signal inputted to the moving picture coding apparatus in the frame immediately before or immediately after. It is detected whether it is the same as the moving image signal of. Further, the moving image recording / reproducing apparatus according to the present invention refers to the moving image signal switching information supplied from the external device, and the moving image signal input to the moving image encoding apparatus is the moving image of the frame immediately before or immediately after. It is detected whether it is the same as the signal. Therefore, the processing in the image switching detecting means can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing a system configuration including a moving picture coding device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing an example of moving image encoding operation timing for ⅓ double speed slow reproduction.

FIG. 3 is a schematic diagram showing an example of moving image encoding operation timing for ⅕ speed slow reproduction.

FIG. 4 is a schematic diagram showing an example of a moving image encoding operation timing for a moving image signal including a portion where normal reproduction is changed to 1/3 speed slow reproduction.

FIG. 5 is a schematic diagram showing an example of moving image coding operation timing for a moving image signal including a portion where 1/3 × slow speed reproduction is changed to normal reproduction.

FIG. 6 is a block diagram showing a configuration of a moving image recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of a moving image recording / reproducing apparatus which decodes a DV input signal, MPEG-encodes it again, and records / reproduces it.

FIG. 8 is a block diagram showing a configuration example of a system including a conventional moving picture re-encoding device.

FIG. 9 is a block diagram showing a configuration example of a video encoder in a conventional moving image reencoding device.

FIG. 10 is a schematic diagram showing the operation timing of a conventional moving image re-encoding device.

[Explanation of symbols]

1 Video signal input terminal 2 Moving image signal storage buffer 3 Screen switching detection circuit 4 B and P picture coded data generator with 0 difference 5 Encoding control unit 6 DCT processing unit 7 Quantizer 8 prediction memory "1" 9 Prediction memory “2” 10 averaging circuit 11 Inverse quantizer 12 Inverse DCT processing unit 13 Video data output terminal 21 Video signal input terminal 22 Video input signal selector 23 MPEG Encoding Unit 24 MPEG Decoding Unit 25 Recording / playback signal processing unit 26 IEEE 1394 terminal 27 recording media 28 System controller 29 Video signal output terminal 30 DV decoding unit 31 Video output signal selector 110 data separation unit 111 Voice data buffer memory 112 Moving image data buffer memory 113 Sub-picture data buffer memory 114 Navigation data buffer memory 115 audio decoder 116 video decoder 117 Sub-picture decoder 118 Video overlay processor 119 Adder 120 GUI image signal generator 121 audio encoder 122 video encoder 123 frame memory 124 re-encoding unit voice data buffer memory 125 re-encoding unit moving image data buffer memory 126 Multiplexer 127 IEEE 1394 interface 128 re-encoding unit 129 Audio signal D / A converter 130 Video signal D / A converter 131 data memory 150 optical disk device 151 voice data 152 moving image data 153 Sub video data 154 navigation data 155 audio signal 156 Video signal 157 Sub video signal 158 video signal 159 GUI image signal 160 User Operations 161, 162 analog signals 164 encoding parameters 165 motion vector information 170 Motion compensation unit 172 Motion Compensation Mode and DCT Type Determining Unit 173 Rate control unit 174 DCT processing unit 175 Quantizer 176 Dequantization unit 177 Inverse DCT processing unit 178 Variable length coding unit 180 generated code amount

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5C053 FA23 GA11 GB22 GB30 GB32                       GB37 HA22 HA23 KA04 KA08                       KA09                 5C059 MA00 MA05 MA14 MA23 MC11                       MC38 PP05 PP06 PP07 RB02                       SS16 TA17 TB03 TC03 TD12                       UA02 UA05 UA33 UA38

Claims (9)

[Claims] 1. A moving picture coding apparatus for coding a moving picture signal, wherein an image for detecting whether or not the moving picture signal to be coded is the same as the moving picture signal of the immediately preceding or following frame. Switching detection means, moving picture coding means for coding moving picture signals to generate moving picture coded data, and difference 0 coded data generation means for generating coded data of B picture with difference 0 And coded data selection means for selecting coded data output from the moving picture coding means and coded data output from the difference 0 coded data generation means. The means outputs the coded data output from the moving image coding means and the code output from the difference 0 coded data generation means based on the information detected by the image switching detection means. Video encoding apparatus characterized by selecting one of the data. 2. The coded data selecting means, when the moving image signal to be coded is the same as the image of the immediately following frame, the direction of the difference 0 opposite to the difference 0 output from the coded data generating means for the difference 0. It is characterized in that the predictive B picture encoded data is selected, and when the moving image signal to be encoded is different from the image of the immediately following frame, the encoded data output from the moving image encoding means is selected. The moving picture coding apparatus according to claim 1. 3. An upper limit of the number of pictures forming the GOP is set, and the number of pictures forming the GOP is variable below the set upper limit value according to the slow reproduction speed of the input moving image signal. The moving picture coding apparatus according to claim 2. 4. A moving picture coding apparatus for coding a moving picture signal, an image for detecting whether or not the moving picture signal to be coded is the same as the moving picture signal of the immediately preceding or following frame. Switching detection means, moving picture coding means for coding moving picture signals to generate moving picture coded data, and differential 0 coded data for generating coded data of B and P pictures with a difference of 0 The encoding means further comprises: generating means; and encoded data selecting means for selecting encoded data output from the moving image encoding means and encoded data output from the difference 0 encoded data generating means. The data selecting means outputs the encoded data output from the moving image encoding means and the difference 0 encoded data generating means based on the information detected by the image switch detecting means. Video encoding apparatus characterized by selecting one of that the coded data. 5. The number of pictures forming a GOP and the cycle in which an I picture or a P picture appears are set, and the coded data selection means determines that the moving picture signal to be coded is the same as the picture of the frame immediately before or immediately after. , B picture or P picture, the backward prediction B picture encoded data of the difference 0 output from the difference 0 encoded data generating means, the forward prediction B picture encoding of the difference 0. If either the data or the forward-predicted P-picture encoded data with a difference of 0 is selected and the moving image signal to be encoded is different from the image of the immediately following frame, it is output from the moving image encoding means. The moving picture coding apparatus according to claim 4, wherein coded data to be selected is selected. 6. The image switching detection means compares the moving image signal accumulated in the buffer memory for encoding by the moving image encoding means with the input moving image signal, so that immediately before or immediately after. 2. It is detected whether or not it is the same as the moving image signal of the frame.
Alternatively, the moving picture coding device according to the item 4. 7. The image switching detection unit refers to switching information of a moving image signal supplied from the outside, and determines whether the input moving image signal is the same as the moving image signal of the immediately preceding or following frame. The moving picture coding apparatus according to claim 1 or 4, which detects whether or not. 8. A moving image recording / reproducing apparatus for recording / reproducing encoded data obtained by encoding a moving image signal, wherein the moving image encoding apparatus according to claim 1 or 4 records / reproducing the moving image encoded data. A recording medium for reproducing the encoded data, and a moving picture decoding means for decoding the encoded data. When performing slow reproduction or still reproduction of the signal recorded on the recording medium, the moving picture decoding means Generating switching information as to whether or not the decoded moving image signal is the same as the moving image signal of the immediately preceding or subsequent frame, and referring to the switching information by the image switching detection means in the moving image encoding device. A moving image recording / reproducing apparatus, which detects whether or not it is the same as a moving image signal of a frame immediately before or immediately after. 9. A moving image recording / reproducing apparatus for recording / reproducing encoded data obtained by encoding a moving image signal, wherein the moving image encoding apparatus according to claim 1 or 4 records / reproducing the moving image encoded data. And a moving picture decoding means for decoding moving picture coded data supplied from an external device. When the external device performs slow reproduction or still reproduction, the moving picture decoding is performed. The means for generating switching information as to whether or not the moving image signal decoded based on the screen switching information added to the moving image encoded data is the same as the moving image signal of the frame immediately before or immediately after, An image switching detection means in the image coding apparatus detects whether or not it is the same as the moving image signal of the immediately preceding or following frame by referring to the switching information. A moving image recording / reproducing device.