JP4405272B2 - Moving picture decoding method, moving picture decoding apparatus and program - Google Patents

Description

  The present invention relates to a moving image encoding method for encoding a moving image signal in units of pictures, a moving image decoding method for decoding the encoded moving image signal, and a program for implementing the same in software. About.

  In recent years, the multimedia era has come to handle voice, image, and other pixel values in an integrated manner, and conventional information media, that is, means for transmitting information such as newspapers, magazines, televisions, radios, telephones, etc., to people have become multimedia. It has come to be taken up as a target. In general, multimedia refers to not only characters but also figures, sounds, especially images, etc. that are associated with each other at the same time. It is an essential condition.

  However, when the amount of information possessed by each information medium is estimated as the amount of digital information, the amount of information per character in the case of characters is 1 to 2 bytes, whereas in the case of speech, 64 Kbits (phone quality) In addition, for a moving image, an information amount of 100 Mbits (current television reception quality) or more per second is required, and it is not realistic to handle the enormous amount of information in the digital format as it is with the information medium. For example, videophones have already been put into practical use by the Integrated Services Digital Network (ISDN) with a transmission speed of 64 Kbit / s to 1.5 Mbits / s, but the video from the TV camera is sent as it is via ISDN. It is impossible.

Therefore, what is needed is information compression technology. For example, in the case of videophones, videos of H.261 and H.263 standards recommended by the ITU-T (International Telecommunication Union Telecommunication Standardization Sector) Compression techniques are used. Further, according to the MPEG-1 standard information compression technology, it is possible to put image information together with audio information on a normal music CD (compact disc).
Here, MPEG (Moving Picture Experts Group) is an international standard of moving picture signal compression standardized by ISO / IEC (International Electrotechnical Commission International Electrotechnical Commission). It is a standard that compresses information of TV signals to about 1/100 up to 5 Mbps. In MPEG-1 standard, the target quality is medium quality that can be realized at a transmission speed of approximately 1.5 Mbps. Therefore, MPEG-2 standardized to meet the demand for higher image quality. Then, the TV broadcast quality is realized at 2 to 15 Mbps for the moving image signal. Furthermore, at present, the working group (ISO / IEC JTC1 / SC29 / WG11), which has been standardizing with MPEG-1 and MPEG-2, has achieved a compression ratio that exceeds MPEG-1 and MPEG-2, and further, on a per-object basis. MPEG-4, which enables encoding / decoding / operation and realizes new functions required in the multimedia era, has been standardized. In MPEG-4, it was originally aimed at standardizing a low bit rate encoding method, but now it has been extended to a more general purpose encoding including a high bit rate including interlaced images. Furthermore, at present, standardization activities of MPEG-4 AVC and ITU H.264 are in progress as a next-generation image encoding method with a higher compression rate jointly by ISO / IEC and ITU-T. As of August 2002, a next-generation image coding method called a committee draft (CD) has been issued (see, for example, Non-Patent Document 1).

  In general, in encoding of moving images, the amount of information is compressed by reducing redundancy in the time direction and the spatial direction. Therefore, in inter-picture predictive coding for the purpose of reducing temporal redundancy, motion is detected and a predicted image is created in units of blocks with reference to the forward or backward picture, and the resulting predicted image and the encoded image are encoded. Encoding is performed on the difference value from the target picture. Here, a picture is a term representing a single screen, which means a frame in a progressive image and a frame or field in an interlaced image. Here, an interlaced image is an image in which one frame is composed of two fields having different times. In interlaced image encoding and decoding processing, one frame may be processed as a frame, processed as two fields, or processed as a frame structure or a field structure for each block in the frame. it can.

  A picture that does not have a reference picture and performs intra prediction coding is called an I picture. A picture that performs inter-frame predictive coding with reference to only one picture is called a P picture. A picture that can be subjected to inter-picture prediction coding with reference to two pictures at the same time is called a B picture. The B picture can refer to two pictures as an arbitrary combination of display times from the front or the rear. A reference picture (reference picture) can be specified for each block, which is a basic unit of encoding and decoding, but the reference picture described earlier in the encoded bitstream is the first reference picture. The one described later is distinguished as the second reference picture. However, as a condition for encoding and decoding these pictures, the picture to be referenced needs to be already encoded and decoded.

  Motion compensation inter-picture prediction coding is used for coding a P picture or a B picture. The motion compensation inter-picture prediction encoding is an encoding method in which motion compensation is applied to inter-picture prediction encoding. Motion compensation is not simply predicting from the pixel value of the reference frame, but detecting the amount of motion of each part in the picture (hereinafter referred to as a motion vector) and performing prediction in consideration of the amount of motion. This improves the prediction accuracy and reduces the amount of data. For example, the amount of data is reduced by detecting the motion vector of the encoding target picture and encoding the prediction residual between the prediction value shifted by the motion vector and the encoding target picture. In the case of this method, since motion vector information is required at the time of decoding, the motion vector is also encoded and recorded or transmitted.

The motion vector is detected in units of macroblocks. Specifically, the macroblock on the encoding target picture side is fixed, the macroblock on the reference picture side is moved within the search range, and is most similar to the reference block. The motion vector is detected by finding the position of the reference block.
FIG. 19 is a block diagram showing a configuration of a conventional moving image encoding apparatus.

The moving image encoding apparatus includes a motion detection unit 103, a subtraction operation unit 104, an encoding unit 105, a motion compensation unit 106, a variable length encoding unit 107, a decoding unit 108, an addition operation unit 109, and memories 110 and 111. I have.
The moving image signal Vin is input to the subtraction operation unit 104 and the motion detection unit 103.
The motion detecting unit 103 uses the encoded decoded image data read from the memory 110 as a reference picture, detects a motion vector MV indicating a position predicted to be optimal in the search region in the picture, and performs motion compensation To the unit 106.

The motion compensation unit 106 generates a motion compensated image signal MCRef using the motion vector MV detected by the motion detection unit 103, and outputs the motion compensated image signal MCRef to the subtraction operation unit 104 and the addition operation unit 109.
The subtraction operation unit 104 calculates a difference between the input moving image signal Vin and the motion compensated image signal MCRef input from the motion compensation unit 106, and outputs the difference signal Dif to the encoding unit 105.
The encoding unit 105 performs encoding processing such as frequency conversion and quantization on the input differential signal Dif, generates an encoded signal, and outputs the encoded signal to the variable length encoding unit 107 and the decoding unit 108. The variable length encoding unit 107 performs variable length encoding or the like on the input encoded signal, and further adds a motion vector MV or the like input from the motion compensation unit 106 to generate an encoded stream Str. And output to the outside of the moving picture coding apparatus.

The decoding unit 108 performs decoding processing such as inverse quantization and inverse frequency conversion on the input encoded signal, and outputs the decoded difference signal RecDif to the addition operation unit 109.
The addition operation unit 109 adds the difference signal RecDif input from the decoding unit 108 and the image signal RecMCRef input from the motion compensation unit 106 to generate a local decoded image LocalRecon. The generated local decoded image LocalRecon is output to the memory 111.

  The local decoded image is an image that matches the result decoded by the moving image decoding apparatus, and is used as a reference image when the moving image signal Vin at the next time is encoded. Therefore, the local decoded image LocalRecon written in the memory 111 is copied to the memory 110 before the next moving image signal Vin is input, or the memory 110 and the memory 111 are exchanged.

  FIG. 20 is a diagram for explaining the concept of JVT display order information (Picture Order Count: POC) and frame number (Frame Number: FN). The display order information POC indicates the display order of pictures. However, it does not mean the actual display time. For example, the display order information POC of the picture IDR19 in the figure is “0”, and the POC of the next picture B20 is “1”, so that it is understood that the picture B20 should be displayed next to the picture IDR19, but how much I don't know if it should be displayed after elapse of time. The actual display time is obtained from data other than video associated with each picture, and is managed by an apparatus not involving a video decoder (moving picture decoding apparatus). The display order information POC is always reset to “0” in an IDR picture that is a special intra picture, and is given so as to increase by 1 in picture units in the display order. When it reaches a predetermined maximum value, it is reset to “0” again. In the example shown in the figure, the display order information POC returns to “0” in the picture IDR19 and the picture IDR29 which are IDR pictures, and the maximum value of the display order information POC is set to “4”. It shows a state where it returns to “0” by circulation.

  FN is a number assigned to the referenced picture. In the figure, (A) shows the state of the memory before decoding the picture B21, in which three reference pictures are stored. (B) in the figure shows a state after the picture B21 is decoded and stored in the memory. Here, the FN of the picture B21 has the same value as the picture P25 to be decoded next. However, when a plurality of consecutive pictures in the decoding order have the same FN, the last picture in the decoding order is the reference picture. This means that the other pictures are not reference pictures. In this example, since the picture B21 is not a reference picture, it is marked as “unused as a reference picture” when stored in the memory (the marked state is abbreviated as “unused”). When the reference picture is stored in the memory, it is marked as “used as a reference picture” (the marked state is abbreviated as used). In the figure, only “unused” is described. Whether or not it is a reference picture can also be seen from a field called nal_ref_idc in the encoded stream, but is not described here because it is not directly related to the description of the present invention. Similarly to the display order information POC, the frame number FN is always reset to “0” in the IDR picture. When the frame number FN reaches a predetermined maximum value, the frame number FN is reset to “0” again. In this example, the picture IDR19 and the picture IDR29 are reset to “0” and the picture B24 is returned to “0”.

  The operation of erasing a picture to secure a free area from the memory will be described with reference to FIGS. FIG. 21 is a diagram for explaining an erasing operation when there is an unused picture. It is assumed that a picture obtained by decoding pictures IDR19, P22, B20, and B21 is stored in the memory immediately before decoding picture P23, and picture B20 is a picture that is not referred to, so it is unused in advance (see (A) in the figure). Next, a picture is unused as necessary using a memory management control operation (MMCO) that performs memory management or a sliding window or the like that becomes unnecessary in order from the oldest. These operations are referred to as unused marking processing in this specification. Here, it is assumed that the picture P22 is unused (see (B) in the figure). Next, a picture is erased in order to secure an empty area. If there is an unused picture in this way, the picture with the earliest display order (POC) is erased among the unused pictures. Here, since the display order of the picture P22 is “3” and the display order of the picture B20 is “1”, the picture B20 is deleted (see (C) in the figure). The picture P23 is stored in this erased and empty area (see (D) in the figure).

Note that a picture has a frame and a field, and is described as a picture in this specification, but when stored in a memory, it may be stored in units of frames (odd and even fields at the same time). Further, when erasing to secure an empty area in the memory, it may be erased in units of frames.
The number indicated by stage in the figure indicates the transition stage of the memory, stage 1 is the stage before the unused mark processing in the processing of the picture, stage 2 is the stage after the unused mark processing, Stage 3 means the stage after the free space is secured, and stage 4 means the stage after the picture is stored.

  FIG. 22 is a diagram for explaining an erasing operation when there is no unused picture in the memory. As shown in the figure, pictures are decoded in the order of picture IDR19, P22, B20, B21, and P23. As shown in (A) in the figure, it is assumed that the pictures of IDR19, P22, B20, and B21 are stored in the memory before decoding the picture P23, and none of them are unused. As shown in (B) in the figure, it is assumed that none is used in the unused marking process. As described above, when there is no unused picture, the first decoded picture is erased from the pictures stored in the memory when an empty area is secured. As shown in (C) in the figure, IDR19 is erased because IDR19 is the first decoded picture among the pictures stored in the memory. Finally, as shown in (D) in the figure, the decoded picture P23 is stored in an empty area.

FIG. 23 is a block diagram showing a configuration of a conventional moving picture decoding apparatus.
The moving picture decoding apparatus includes a variable length decoding unit 402, an image decoding unit 202, an MMCO decoding unit 204, a memory 206, and a memory management unit 401.
The video encoded signal Str is input, the variable length decoding unit 402 performs variable length decoding, the encoded picture data comp_pic is decoded by the image decoding unit 202, and the decoded image signal Recon is stored in the memory 206. To store. When the picture is inter-coded, the image decoding unit 202 sends the motion information MV to the memory 206 at the time of decoding, creates a motion compensated reference image MCPic, and performs motion compensation. The memory management unit 401 outputs a memory management instruction mctrl, such as determining a picture storage area and securing a free area. The display order information POC is output from the variable length decoding unit 402 to the memory management unit 401 and held. Also, the MMCO command MMCO, which is one of the above-described unused marking processes, is input from the variable length decoding unit 402 to the MMCO decoding unit 204, decoded, and an unused instruction is input to the memory management unit 401. Also, a decoded image signal Vout displayed from the memory 206 is output.

  FIG. 24 is a flowchart of memory-related operations of the conventional video decoding device. This flow shows the operation in units of pictures in steps S1 to S2. Unused marking processing is performed, and each picture in the memory is marked as unused as necessary (step S13). Next, a free area securing process is performed to secure a free area in the memory (step S14). Next, the decoded image signal Vout is stored in the empty area (step S15).

  FIG. 25 is a flowchart of the operation of the free area securing process of the conventional video decoding device, and is a flowchart for explaining step S14 of FIG. 24 in detail. The process of securing the free space (step S14) checks whether there is a picture marked as “unused” in the memory 206 (step S141). If there is a picture, it is included in the picture marked as “unused” stored in the memory 206. In step S143, the oldest picture in the display order is deleted (step S143). If not, the first decoded picture is deleted from the pictures stored in the memory 206 (step S142).

  FIG. 27 is a conceptual diagram illustrating the operation of invalid picture processing. In JVT, a memory management operation is defined such that when some pictures in a sequence input to a video decoding device are lost, invalid pictures are inserted by the number of lost pictures. This operation is performed in the video decoding device when required_frame_num_update_behaviour_flag in the sequence parameter set is “1”. An invalid picture is a picture that is not marked with an actual restored image signal and is specially marked and should not be referred to as a reference picture. Assume that the state of the memory after decoding pictures I19, P20, P21, P22, and P23 as shown in the figure is the state shown in FIG. Next, when the picture B24 is decoded, a reference index used to identify the reference picture is assigned so that the value of the reference index ref_idx is reduced to a new unused picture in the decoding order. This allocation is an example, and the method differs depending on the picture type or the like, but the same dependency characteristic is that a reference-related index is allocated depending on the picture stored in the memory. In the example of this figure, the last unused picture P22 decoded is assigned ref_idx = 0, and the previously unused picture P21 decoded before that is assigned ref_idx = 1.

  Here, when the picture P21 and the picture P23 are lost in the middle of transmission or the like and are not input to the decoder, unless an invalid picture is inserted, when decoding the picture B24, as shown in FIG. A reference index ref_idx is assigned. Originally, the picture P22 and the picture P20 referred to by the picture B24 are respectively assigned as ref_idx = 0 and ref_idx = 2, but ref_idx = 0 is assigned to the picture P22 and ref_idx = 2 is assigned to the picture I19. There is a problem that the picture I19 is referred to by mistake. In order to avoid this, an invalid picture is inserted.

  FIG. 4C shows the state of the memory before decoding the picture B24 when an invalid picture is inserted. If a discontinuity in frame number FN is detected, invalid pictures are inserted for the number of discontinuous frames. In this example, when the picture P22 with FN = 3 is decoded, the picture P20 decoded immediately before is FN = 1, so that the place where it originally does not increase by 1 is increased by 2, so it can be seen that one was lost. . Therefore, one invalid picture is inserted before decoding the picture P22. As mentioned above, an invalid picture is a special picture that does not have an actual restored image signal, but is marked as used and is treated as a reference picture when assigning a reference picture, but it is not actually referenced. In addition, it is marked as “non-exist”.

  FIG. 28 is a block diagram showing a configuration of a conventional moving picture decoding apparatus. The difference from the conventional video encoding apparatus described in FIG. 23 is that the FN gap detection unit 211 is present and the operation of the memory management unit 412 is different. The FN gap detection unit 211 acquires the frame number FN from the variable length decoding unit 411, and when there is a gap, instructs the memory management unit 412 to insert as many invalid pictures as necessary. The memory management unit 412 stores invalid pictures in the memory 206 as many as the designated number.

  FIG. 29 is a flowchart of the invalid picture processing operation of the conventional video decoding apparatus. The difference from the memory-related operation of the conventional video decoding apparatus described with reference to FIG. 24 is that the gap of the frame number FN is checked (step S11) before the unused marking process (step S13). In step S12, invalid pictures corresponding to the number of gaps are stored in the memory 206 (step S12), and the process proceeds to the unused marking process (step S13). If there is no gap, the process proceeds to the unused marking process (step S13). . In step S12, invalid pictures are stored as many as the number of gaps, but each time an attempt is made to insert one, the same processing as that for storing a normal picture shown in FIG. 24 is performed.

  FIG. 31 is a conceptual diagram illustrating the structure of a conventional MPEG-2 stream. As shown in the figure, the MPEG2 stream has the following hierarchical structure. A stream is composed of a plurality of group of pictures. By using this as a basic unit of encoding processing, editing of a moving image and random access are possible. The group of pictures is composed of a plurality of pictures, and each picture includes an I picture, a P picture, or a B picture. The stream, GOP, and picture are further composed of a synchronization signal (sync) that indicates the division of each unit and a header that is data common to the unit. In MPEG-2, P pictures can be predictively encoded with reference to only one I picture or P picture whose display time is immediately before. The B picture can be predictively encoded with reference to one I picture or P picture whose display time is one immediately before and one immediately after. Further, the order of arrangement in the stream is also determined, and is arranged immediately after the I picture or P picture. Therefore, if decoding is started from an I picture at the time of random access, all pictures arranged after the I picture can be decoded and displayed. In addition, since up to two reference pictures can be stored in the memory, the degree of freedom of the reference structure has been limited.

  FIG. 32 is a conceptual diagram for explaining a conventional video coding method of JVT. In JVT, it is possible to refer to arbitrarily distant pictures as long as they do not cross IDR pictures which are special intra pictures. Therefore, for example, in order to increase the encoding efficiency, it is possible to rearrange the encoding order of a large number of pictures for encoding. In the figure, it is assumed that the correlation between images of pictures 19, 20, 21, 25, 26, and 27 is very strong, and the correlation between images of pictures 22, 23, 24, 28, 29, and 30 is very strong. In this case, pictures 19, 20, 21, 25, 26, and 27 are first inter-coded (GOP1), and pictures 22, 23, 24, 28, 29, and 30 are inter-coded (GOP2). It can be expected that the encoding efficiency is increased.

FIG. 33 is an operation flowchart of the conventional JVT moving image encoding method. In the JVT moving image encoding method, all uncoded pictures can be set as encoding candidates (step S55). Then, a picture is selected from the encoding candidates from some viewpoint and encoded (step S56). For example, when there are 10 uncoded pictures, all 10 pictures may be used as coding candidates, and the 10th picture may be selected and displayed in the display order. If there is an unencoded picture after encoding, the process returns to step S55. In step S56, it may wait for an unencoded picture to be input without encoding.
ISO / IEC 14496-10 Editor's Proposed Changes Relative to JVT-E146d37ncm, revision 4, 2002-12

Now, with such a conventional video decoding device and a conventional video decoding device, the encoded stream cannot be edited except for the location of the IDR picture which is a special intra picture as described above. It was. This problem will be described below.
FIG. 26 is a conceptual diagram illustrating a problem in which discontinuity of a sequence causes discontinuity of display order information POC and an undisplayed picture is deleted. A case where two parts Clip1 and Clip2 of a sequence are connected and decoded is shown. A place where the discontinuity of the sequence generated by editing or the like occurs is called an edit point. In this example, it is assumed that the maximum value of the display order information POC is set such that the display order information POC need not be considered. (A) in the figure shows the state of the memory after decoding Clip1, and pictures I19, P22, B20, and B21 are stored therein. Each display order information POC is “4”, “7”, “5”, “6”, respectively, as shown in the figure, and pictures I19, B20, B21 are marked as unused. Next, a state before decoding the first picture I85 of Clip2 and before decoding the second picture P86 is shown in FIG. Here, it is assumed that the picture I85 is stored at the position where the picture B20 was located. Next, unused marking processing is performed. In the case of Clip2, it is assumed that the picture I85 is marked as unused ((B) in the figure). Next, an empty area securing process is performed. As described above, since there is an unused picture, the picture having the first display order is deleted from the unused pictures, so the picture I85 is deleted. Here, assuming that the average delay from decoding to display is three, pictures B21, P22, and I85 have not been displayed yet. However, the picture I85 is erased from the memory even though it is not displayed yet.

  FIG. 30 is a conceptual diagram for explaining the problem that the discontinuity of the sequence causes the discontinuity of the frame number FN and the invalid picture erases the undisplayed picture. In this example, the discontinuous parts Clip1 and Clip2 of a sequence are connected and decoded. FIG. 9A shows the state of the memory after decoding the picture P25, and five pictures from the picture P21 to the picture P25 are stored. Next, when the first picture I60 of Clip2 is decoded, the state after the invalid picture is inserted is shown in FIG. Since the picture I60 is FN = 12, and the picture P25 decoded immediately before is FN = 5, it is determined that six pictures have been lost, and six invalid pictures are inserted. In this case, since all the pictures in the memory are erased, there is a problem that even if the pictures P23, P24, and P25 are not yet displayed in the state of FIG.

  FIG. 34 is a conceptual diagram for explaining a problem caused by the degree of freedom of JVT encoding at the time of editing or random access. FIG. 5B shows the original stream, which is the same as the stream shown in FIG. FIG. 2A shows a state in which only GOP2 is decoded without GOP1. In this case, since pictures 25, 26, and 27 cannot be obtained, a reproduction discontinuity occurs in which after reproduction from picture 22 to picture 24, picture 25 to picture 27 cannot be reproduced. This becomes a problem when GOP1 is deleted by editing, or when random access is made from GOP2. FIG. 4C shows a state where GOP2 is not decoded and GOP1 is decoded. In this case, since the pictures 22, 23, and 24 are not obtained, a discontinuity of reproduction occurs. This becomes a problem when GOP2 is deleted by editing.

The present invention has been made in view of the above circumstances, it aims to provide a special moving picture decoding method in place of the picture other than the IDR picture Ru can edit such an intra-picture And

To achieve the above object, a moving picture decoding method according to the present invention is a moving picture decoding method for decoding a coded stream in units of pictures, and indicates that the order of the pictures is discontinuous. An information extracting step of extracting flag information and a management step of managing an area for storing a decoded picture based on the flag information are characterized.

The flag information is information indicating that display order information of pictures is discontinuous. In the management step, the decoding stored in the area is performed based on the display order information and the flag information. It is also possible to determine a picture with the earliest display order among the completed pictures and use the determined picture as a deletion target picture.
As a result, it is possible to prevent the non-displayed picture from being erased due to the discontinuity of the display order information of the pictures.

  The moving picture decoding method further includes an invalid picture storing step of storing an invalid picture in the area when the picture coding order information is discontinuous, and the flag information includes the coding order information. Information indicating that the information is discontinuous. In the management step, it is determined whether to store an invalid picture in the area based on the flag information and the coding order information, and the invalid picture storage In the step, an invalid picture may be stored in the area based on a determination result in the management step.

As a result, it is possible to prevent the undisplayed picture from being erased due to the discontinuity of the coding order information of the picture.
Furthermore, the present invention is such not only can be realized as a moving picture decoding method, and realized characteristic steps such dynamic image decoding method comprises a moving image decoding apparatus Ru comprising a means Or can be realized as a program that causes a computer to execute these steps. Needless to say, such a program can be distributed via a recording medium such as a CD-ROM or a transmission medium such as the Internet.

As is clear from the above description, according to the moving picture decoding method according to the present invention, editing can be performed at a place of a picture other than an IDR picture which is a special intra picture.

Embodiments of the present invention will be described below with reference to the drawings.
(Embodiment 1)
FIG. 1 is a block diagram showing the configuration of the moving picture coding apparatus according to the present embodiment.
The moving image encoding apparatus includes a motion detection unit 103, a subtraction operation unit 104, an encoding unit 105, a motion compensation unit 106, a variable length encoding unit 113, a decoding unit 108, an addition operation unit 109, memories 110 and 111, and A flag information generation unit 112 is provided.

The difference from the conventional moving image coding apparatus (FIG. 19) is that a flag information generation unit 112 and a variable length coding unit 113 whose operation is different from that of the variable length coding unit 107 are provided.
When the display order information POC becomes discontinuous due to editing or the like, the flag information generation unit 112 generates a flag indicating that the display order information POC is discontinuous.
The variable length encoding unit 113 performs variable length encoding or the like on the input encoded signal, and further generates a flag generated by the flag information generation unit 112, a motion vector MV input from the motion compensation unit 106, and the like. The encoded stream Str is generated by adding the above information and output to the outside of the moving image encoding apparatus.

  FIG. 2 is a diagram for explaining the concept of the moving picture coding method and the moving picture decoding method of the present invention. This figure explains how to solve the case of FIG. First, it is detected by a flag added at the time of encoding that the display order information POC is discontinuous by editing or the like. This flag is referred to as flag A. The flag A is a flag indicating that the display order information POC is discontinuous due to editing or the like.

  As shown in the figure, this flag A is special information placed immediately before the Clip. In JVT, a unit for storing additional information of video decoding called supplemental enhancement information (hereinafter abbreviated as SEI) is defined and stored in this unit. It may be stored in User data registered SEI that can be defined by the user, or may be stored in Random access point SEI (hereinafter abbreviated as RAP SEI) that stores information for random access. RAP SEI has broken_link_flag indicating that the video decoded by editing etc. may be different from the original video, and the video decoded from the nth picture in the display order from the position where RAP SEI is When it is equivalent to or almost equivalent to a moving image, information such as recovery_frame_cnt indicating the n images is stored. In the present invention, when broken_link_flag of RAP SEI is “1”, it is detected that editing is being performed, and an edit point is set immediately before the first picture after RAP SEI. Alternatively, an edit point is set immediately before the picture indicated by recovery_frame_cnt. Alternatively, the first independently decodable picture (for example, Intra Picture) after RAP_SEI is set as the edit point. The edit point refers only to the picture boundary, and does not define the SEI boundary. In addition, the random access information of each picture may be stored in the file format storing the sequence, and information indicating that the picture is edited, and further information on the editing point May be stored. In that case, the detection of editing and the identification of the editing point may be performed in accordance with the file format information. These storage formats are called flag format A storage formats.

FIG. 3 is a block diagram showing a configuration of the moving picture decoding apparatus according to the present embodiment. The difference from the conventional video decoding device (FIG. 23) is that an edit detection unit 203 is added and a memory management unit 205 having an operation different from that of the memory management unit 401 is provided.
The edit detection unit 203 acquires a flag indicating that the display order information POC is discontinuous from the variable length decoding unit 201 or information for storing the edit point information, analyzes it, and controls it to the memory management unit 205. The signal mctrlc is output. When the control signal mctrlc indicating editing is input, the memory management unit 205 manages the picture before the editing point so that the display order is ahead of the picture after the editing point. That is, when the picture to be deleted is selected from the unused pictures, the display order of the picture before the editing point is assumed to be before the picture after the editing point.

  In order to manage the display order, the memory management unit 205 causes each picture to hold a Clip counter that is incremented by 1 each time an edit point is exceeded. As shown in (B) in the figure, pictures B20, P22 and B21 are recorded as Clip = 1, and picture I85 after the edit point is recorded as Clip = 2. In the unused marking process in this state, the previous picture B20 in the display order is deleted from the picture of the clip decoded first in the unused picture (pictures B20, P22, and B21 marked with Clip = 1). . This solves the problem of deleting an undisplayed picture (picture I85 in the conventional problem).

  FIG. 4 is an operation flowchart of the moving picture decoding method according to the present embodiment. The difference from the conventional video decoding method (FIG. 24) is that step S31 and step S32 are added, and step S14 is modified to step S14B. After the start of processing in units of pictures (step S1), it is checked whether or not editing has been performed (step S31). If no edit is detected, the unused marking process (step S13) is performed as in the conventional case, and the free area securing process (step S14B) is performed in consideration of the decoding order before and after the edit point. The processing at the edit point is to make it possible to distinguish before and after the edit point, and the memory management unit 205 increments the Clip counter by one every time the edit point is exceeded.

  FIG. 5 is an operation flowchart of the free space securing process of the moving picture decoding method according to the present embodiment. The difference from the conventional free area securing method (FIG. 24) is step S43B obtained by correcting step S43. If an unused picture is stored in the memory (step S41), the clip including the unused picture is searched for in priority of the previous clip in the decoding order, and the first picture in the display order among the unused pictures of the clip is searched. Is deleted. In other words, the unused picture in the Clip including the first unused picture in the decoding order, and the first picture in the display order is deleted from these pictures. Or, in other words, the first display order picture is deleted from the unused pictures included between the edit points immediately before and after the first unused picture in the decoding order.

As described above, since the display order information POC is discontinuous due to editing or the like is detected based on the flag added at the time of encoding, the picture to be deleted is determined. In the example shown in FIG. 26, the problem of deleting picture I85) can be solved.
In order to solve the discontinuity of editing by using the moving picture decoding method of the present invention (FIGS. 2, 3, 4, and 5), information indicating editing points is necessary. Therefore, it is desirable that information indicating that the edit point information is included be in a place where the information can be easily obtained by the decoding apparatus.

  In the present embodiment, a flag added at the time of encoding indicating that the display order information POC is discontinuous is added between pictures in which the display order information POC is discontinuous. It is not limited to this. For example, the flag information generation unit 112 generates a flag indicating that the display order information POC is discontinuous and information specifying a position (edit point) where the display order information POC is discontinuous. It doesn't matter. This information is stored in the sequence parameter set, or stored in User data registered SEI that can be defined by the user, and placed in a place where the sequence can be easily obtained, for example, at the beginning, or the sequence is recorded. Store in a medium or in a file format that manages the sequence. These storage formats are called flag format A2.

In this case, at the time of decoding, the edit detection unit 203 acquires the flag A2 from these locations, and if the edit point information can be obtained, the video decoding method of the present invention (FIGS. 2, 3, 4, and 4). FIG. 5) is performed.
(Embodiment 2)
The configuration of the moving picture coding apparatus according to the present embodiment is the same as the block diagram of the first embodiment shown in FIG.

In the present embodiment, when the frame number FN becomes discontinuous due to editing or the like, the flag information generation unit 112 generates a flag B indicating that the frame number FN is discontinuous.
Note that the flag B generated by the flag information generation unit 112 may be a flag that instructs not to insert an invalid picture. The format of flag B is equivalent to the format of flag A shown in the first embodiment.

FIG. 6 is a block diagram showing a configuration of the moving picture decoding apparatus according to the present embodiment. This figure is obtained by adding an edit detection unit 214 and changing the memory management unit 212 to the conventional moving picture decoding apparatus described with reference to FIG.
The edit detection unit 214 obtains a flag indicating that the frame number FN is discontinuous from the variable length decoding unit 201, and outputs a control signal ctrl_c to the memory management unit 212. Even when an invalid picture insertion request is input from the FN gap detection unit 211 by the control signal ctrl_c from the FN gap detection unit 211, the memory management unit 212 inserts an invalid picture when notified from the edit detection unit 214 that editing has been performed. Will not be performed.

  FIG. 7 is an operation flowchart of the moving picture decoding method of the present invention. The difference from the conventional video decoding method (FIG. 29) is that step S31 is added and step S14 is modified to step S14B. The other steps operate in the same manner as the steps having the same reference numerals in FIG. Further, step S31 and step S14B are the same as step S31 and step S14B of the decoding apparatus of the present invention described in the first embodiment, and thus description thereof is omitted.

As described above, the fact that the frame number FN is discontinuous due to editing or the like is detected by the flag added at the time of encoding, and the insertion of an invalid picture is determined. In the example shown in FIG. 30, the problem of deleting pictures P23, P24, P25) can be solved.
In the present embodiment, as in the first embodiment, a flag added at the time of encoding indicating that the frame number FN is discontinuous is indicated between the pictures having the frame number FN discontinuous. However, this is not a limitation. For example, as in the first embodiment, the flag information generation unit 112 identifies a flag indicating that the frame number FN is discontinuous and a position (edit point) where the frame number FN is discontinuous. Information may be generated. These pieces of information are stored in the same manner as in the first embodiment.

In this case, at the time of decoding, the edit detection unit 203 obtains the flag B2 from these locations as in the first embodiment, and if the edit point information can be obtained, the moving picture decoding method of the present invention (FIG. 6). 7).
FIG. 8 is a diagram showing the structure of data output by the moving picture encoding method of the present invention and the structure of data input by the moving picture decoding method of the present invention in the first and second embodiments. A sequence that is an encoded moving image signal includes RAP, MMCO, and PICTURE data, as shown in FIG. RAP is Random access point SEI, and broken_link_field in the RAP is the flag A in the first embodiment and the flag B in the second embodiment. PICTURE is a moving picture signal encoded in units of pictures, and may or may not have MMCO before PICTURE. MMCO is instruction information for Memory management control operation. Further, as shown in FIG. 5B, the flag A2 of the first embodiment is provided in the sequence, in a predetermined position of the file format associated with the sequence, or in a recording medium for recording the sequence. In addition, the flag B2 in the second embodiment is stored.

(Embodiment 3)
FIG. 9 is a block diagram showing the configuration of the video encoding apparatus according to the present embodiment.
The moving image encoding apparatus includes a rearrangement memory 101, an encoding scheduling unit 102, a motion detection unit 103, a subtraction operation unit 104, an encoding unit 105, a motion compensation unit 106, a variable length encoding unit 107, a decoding unit 108, An addition operation unit 109 and memories 110 and 111 are provided.

The rearrangement memory 101 stores moving images input in units of pictures in the order of display time. The encoding scheduling unit 102 rearranges the pictures stored in the rearrangement memory 101 in the order in which the pictures are encoded.
FIG. 10 is a diagram for explaining the concept of the moving picture coding method according to the present embodiment. The moving picture coding method according to the present embodiment, which solves the problem shown in FIG. 34, stores only consecutive pictures in a display order in a certain GOP, and the display order of an arbitrary picture in a certain GOP is as follows. In other words, encoding is performed so as to be before the display order of an arbitrary picture of the GOP to be decoded. By encoding in this way, there is no reproduction discontinuity in the case shown in FIG. 34 for both GOP1 and GOP2.

  FIG. 11 is an operation flowchart of the moving picture coding method according to the present embodiment. The operation will be described with reference to FIG. Of the uncoded pictures, the picture that is continuous from the front in the display order is set as a display basic unit (step S61). That is, the display basic unit is determined so that one or more pictures that do not become discontinuous in the display order are set as the display basic unit, and there is no uncoded picture that is displayed before the display basic unit. Next, it is checked whether or not there is an uncoded picture in the display basic unit (step S62). If there is (Yes in step S62), an uncoded picture in the display basic unit is set as a coding candidate. Encoding is selected from the encoding candidates (step S63). If there is an uncoded picture (step S64), if there is (Yes in step S64), the process proceeds to step S62. If not (No in step S64), the process ends. Note that the basic display unit includes at least the basic display unit from the picture with the earliest display order in the uncoded picture to the picture with the last display order in the encoded picture. Can be changed at any timing as long as it satisfies "

  FIG. 5B is also an operation flow diagram of the moving picture coding method according to the present embodiment. In this method, coding is performed from the unencoded picture from the previous picture in the display order. Up to the last picture in the display order among the encoded pictures is set as an essential encoding candidate (step S71), and including the essential encoding candidate, it is selected from the unencoded pictures and encoded (step) S72). Next, it is checked whether there is an uncoded picture other than the I picture (step S73). If there is (Yes in step S73), the process proceeds to step S71, and if not (No in step S73), the process ends. Note that the GOP candidates up to the next I picture are used here, but the present invention is not limited to this. For example, the end of the GOP may be determined by the description of the GOP in the file format.

Since the GOP is determined as described above, it is possible to prevent a discontinuity of reproduction from occurring in each of GOP1 and GOP2, for example, as shown in FIG.
Note that a flag indicating that encoding has been performed as described in the present embodiment may be added to the encoded stream.

(Embodiment 4)
FIG. 12 is a diagram for explaining the concept of the moving picture coding method according to the present embodiment. In the third embodiment, the editing problem and the random access problem are solved at the same time. However, the moving picture coding method in the present embodiment is a method for solving the random access problem. . Since the restrictions are looser than the method of the third embodiment, the encoding efficiency and the like can be improved.

  The GOP2 in FIG. 12 will be described as an example. In this moving image encoding method, 1) pictures (B26, B27, P28) whose display time is later than an intra picture (I25) of a certain GOP include the intra picture. Do not encode with GOP (GOP1) immediately before GOP (GOP2). By controlling in this way, it is possible to correctly display all the pictures after the first picture even when decoding is started from the first picture (I25) of GOP2, as indicated by Case A in the figure. .

  2) Furthermore, pictures (I19, B20, B21, B22, display time before the intra picture (I25) immediately before the GOP and display time after the GOP intra picture (I19) immediately before the GOP). B23, P24) is encoded in the GOP (GOP2) or the immediately preceding GOP (GOP1). By controlling in this way, even if decoding is started from the first picture (I19) of GOP1, all the pictures after the first picture (I19) of GOP1 can be correctly displayed.

  Or, in other words, 1) Taking GOP1 as an example, the picture to be displayed at the end of one GOP is selected and encoded such that it is displayed before the I picture (I25) of the next GOP (that is, Picture P24 and earlier must be selected). 2) Taking GOP2 as an example, the picture to be displayed first in a GOP is selected and encoded from the pictures displayed after the I picture (I19) of the immediately preceding GOP (that is, the pictures after picture B20 are selected) Must).

  Or, in other words, the display order of the picture displayed at the beginning of a GOP is later than the I picture of the previous GOP, and the display order of the picture displayed at the end of the GOP is higher than the I picture of the immediately following GOP. This is a moving image encoding method for encoding so that the display order is the front. Although described as an I picture here, the present invention is equally applicable to independently decodable pictures.

  FIG. 13 is an operation flowchart of the moving picture coding method according to the present embodiment. First, an unencoded picture is selected and encoded as an entry picture (step S81). An entry picture is a picture that can be decoded independently. Next, among the uncoded pictures, the picture whose display order is earlier than the last-encoded entry picture is set as an indispensable encoding candidate, and the display order is earlier than the entry picture to be encoded next. These unencoded pictures are set as encoding candidates that can be omitted (step S82). Next, if there is an unencoded picture in the mandatory encoding candidate (step S83), if it is found (Yes in step S83), it is selected from the essential encoding candidate and the optional encoding candidate. And encoding (step S85). Next, it is checked whether there is an uncoded picture (step S86). If there is, the process proceeds to step S83, and if not, the process is terminated. In step S83, if there is no unencoded picture among the essential encoding candidates (No in step S83), it is determined in step S84 whether the next entry picture is to be encoded (step S84). If the entry picture is to be encoded (Yes in step S84), the process proceeds to step S81. If not (No in step S84), the process proceeds to step S85.

As described above, the pictures that are displayed later than the first intra picture in a GOP are encoded so that they are included in the GOP after this GOP, so even if a certain GOP or later is decoded, playback discontinuity occurs. Playback can be done without
Note that a flag indicating that encoding has been performed as described in the present embodiment may be added to the encoded stream.

(Embodiment 5)
Furthermore, by recording a program for realizing the configuration of the moving picture encoding method or the moving picture decoding method shown in each of the above embodiments on a storage medium such as a flexible disk, The processing shown in the form can be easily performed in an independent computer system.

FIG. 14 is an explanatory diagram in the case of implementing by a computer system using a flexible disk storing the moving picture coding method or the moving picture decoding method of each of the above embodiments.
FIG. 14B shows the appearance, cross-sectional structure, and flexible disk as seen from the front of the flexible disk, and FIG. 14A shows an example of the physical format of the flexible disk that is the recording medium body. The flexible disk FD is built in the case F, and on the surface of the disk, a plurality of tracks Tr are formed concentrically from the outer periphery toward the inner periphery, and each track is divided into 16 sectors Se in the angular direction. ing. Therefore, in the flexible disk storing the program, a moving picture encoding method and a moving picture decoding method as the program are recorded in an area allocated on the flexible disk FD.

  FIG. 14C shows a configuration for recording and reproducing the program on the flexible disk FD. When the program is recorded on the flexible disk FD, the moving picture encoding method or the moving picture decoding method as the program is written from the computer system Cs via the flexible disk drive. When the above-described moving picture encoding method and moving picture decoding method are constructed in a computer system by a program in a flexible disk, the program is read from the flexible disk by a flexible disk drive and transferred to the computer system.

In the above description, a flexible disk is used as the recording medium, but the same can be done using an optical disk. Further, the recording medium is not limited to this, and any recording medium such as an IC card or a ROM cassette capable of recording a program can be similarly implemented.
Furthermore, application examples of the moving picture coding method and the moving picture decoding method shown in the above embodiment and a system using the same will be described.

FIG. 15 is a block diagram showing an overall configuration of a content supply system ex100 that implements a content distribution service. The communication service providing area is divided into desired sizes, and base stations ex107 to ex110, which are fixed radio stations, are installed in each cell.
The content supply system ex100 includes, for example, a computer ex111, a PDA (personal digital assistant) ex112, a camera ex113, a mobile phone ex114, a camera via the Internet ex101, the Internet service provider ex102, the telephone network ex104, and the base stations ex107 to ex110. Each device such as the attached mobile phone ex115 is connected.

However, the content supply system ex100 is not limited to the combination as shown in FIG. 15, and any combination may be connected. Further, each device may be directly connected to the telephone network ex104 without going through the base stations ex107 to ex110 which are fixed wireless stations.
The camera ex113 is a device capable of shooting a moving image such as a digital video camera. The mobile phone is a PDC (Personal Digital Communications) system, a CDMA (Code Division Multiple Access) system, a W-CDMA (Wideband-Code Division Multiple Access) system, or a GSM (Global System for Mobile Communications) system mobile phone, Alternatively, PHS (Personal Handyphone System) or the like may be used.

  In addition, the streaming server ex103 is connected from the camera ex113 through the base station ex109 and the telephone network ex104, and live distribution or the like based on the encoded data transmitted by the user using the camera ex113 becomes possible. The encoded processing of the captured data may be performed by the camera ex113 or may be performed by a server or the like that performs data transmission processing. Further, the moving image data shot by the camera ex116 may be transmitted to the streaming server ex103 via the computer ex111. The camera ex116 is a device that can shoot still images and moving images, such as a digital camera. In this case, the encoding of the moving image data may be performed by the camera ex116 or the computer ex111. The encoding process is performed in the LSI ex117 included in the computer ex111 and the camera ex116. Note that moving image encoding / decoding software may be incorporated in any storage medium (CD-ROM, flexible disk, hard disk, or the like) that is a recording medium readable by the computer ex111 or the like. Furthermore, you may transmit moving image data with the mobile telephone ex115 with a camera. The moving image data at this time is data encoded by the LSI included in the mobile phone ex115.

  In this content supply system ex100, the content (for example, video shot of music live) captured by the user with the camera ex113, camera ex116, etc. is encoded and transmitted to the streaming server ex103 as in the above embodiment. On the other hand, the streaming server ex103 distributes the content data to the requested client. Examples of the client include a computer ex111, a PDA ex112, a camera ex113, a mobile phone ex114, and the like that can decode the encoded data. In this way, the content supply system ex100 can receive and reproduce the encoded data at the client, and also realize personal broadcasting by receiving, decoding, and reproducing in real time at the client. It is a system that becomes possible.

For the encoding and decoding of each device constituting this system, the moving image encoding device or the moving image decoding device described in the above embodiments may be used.
A mobile phone will be described as an example.
FIG. 16 is a diagram illustrating the mobile phone ex115 that uses the moving picture coding method and the moving picture decoding method described in the above embodiment. The cellular phone ex115 includes an antenna ex201 for transmitting and receiving radio waves to and from the base station ex110, a camera such as a CCD camera, a camera unit ex203 capable of taking a still image, a video shot by the camera unit ex203, and an antenna ex201. A display unit ex202 such as a liquid crystal display that displays data obtained by decoding received video and the like, a main body unit composed of a group of operation keys ex204, an audio output unit ex208 such as a speaker for audio output, and audio input To store encoded data or decoded data such as a voice input unit ex205 such as a microphone, captured video or still image data, received mail data, video data or still image data, etc. Recording medium ex207, and slot portion ex20 for enabling recording medium ex207 to be attached to mobile phone ex115 The has. The recording medium ex207 stores a flash memory element which is a kind of EEPROM (Electrically Erasable and Programmable Read Only Memory) which is a nonvolatile memory that can be electrically rewritten and erased in a plastic case such as an SD card.

  Further, the cellular phone ex115 will be described with reference to FIG. The cellular phone ex115 controls the power supply circuit ex310, the operation input control unit ex304, and the image coding for the main control unit ex311 which is configured to control the respective units of the main body unit including the display unit ex202 and the operation key ex204. Unit ex312, camera interface unit ex303, LCD (Liquid Crystal Display) control unit ex302, image decoding unit ex309, demultiplexing unit ex308, recording / reproducing unit ex307, modulation / demodulation circuit unit ex306, and audio processing unit ex305 via a synchronization bus ex313 Are connected to each other.

When the end call and power key are turned on by a user operation, the power supply circuit ex310 activates the camera-equipped digital mobile phone ex115 by supplying power from the battery pack to each unit. .
The mobile phone ex115 converts the voice signal collected by the voice input unit ex205 in the voice call mode into digital voice data by the voice processing unit ex305 based on the control of the main control unit ex311 including a CPU, a ROM, a RAM, and the like. The modulation / demodulation circuit unit ex306 performs spread spectrum processing, and the transmission / reception circuit unit ex301 performs digital analog conversion processing and frequency conversion processing, and then transmits the result via the antenna ex201. In addition, the cellular phone ex115 amplifies the received data received by the antenna ex201 in the voice call mode, performs frequency conversion processing and analog-digital conversion processing, performs spectrum despreading processing by the modulation / demodulation circuit unit ex306, and analog audio by the voice processing unit ex305. After the data is converted, it is output via the audio output unit ex208.

  Further, when an e-mail is transmitted in the data communication mode, text data of the e-mail input by operating the operation key ex204 of the main body is sent to the main control unit ex311 via the operation input control unit ex304. The main control unit ex311 performs spread spectrum processing on the text data in the modulation / demodulation circuit unit ex306, performs digital analog conversion processing and frequency conversion processing in the transmission / reception circuit unit ex301, and then transmits the text data to the base station ex110 via the antenna ex201.

  When transmitting image data in the data communication mode, the image data captured by the camera unit ex203 is supplied to the image encoding unit ex312 via the camera interface unit ex303. When image data is not transmitted, the image data captured by the camera unit ex203 can be directly displayed on the display unit ex202 via the camera interface unit ex303 and the LCD control unit ex302.

  The image encoding unit ex312 is configured to include the moving image encoding device described in the present invention, and the image data supplied from the camera unit ex203 is a code used in the moving image encoding device described in the above embodiment. The encoded image data is converted into encoded image data by compression encoding using the encoding method, and is sent to the demultiplexing unit ex308. At the same time, the cellular phone ex115 sends the sound collected by the audio input unit ex205 during imaging by the camera unit ex203 to the demultiplexing unit ex308 as digital audio data via the audio processing unit ex305.

  The demultiplexing unit ex308 multiplexes the encoded image data supplied from the image encoding unit ex312 and the audio data supplied from the audio processing unit ex305 by a predetermined method, and the multiplexed data obtained as a result is a modulation / demodulation circuit unit A spectrum spread process is performed at ex306, a digital-analog conversion process and a frequency conversion process are performed at the transmission / reception circuit unit ex301, and then transmitted through the antenna ex201.

When data of a moving image file linked to a homepage or the like is received in the data communication mode, the received data received from the base station ex110 via the antenna ex201 is subjected to spectrum despreading processing by the modulation / demodulation circuit unit ex306, and the resulting multiplexing is obtained. Is sent to the demultiplexing unit ex308.
In addition, in order to decode multiplexed data received via the antenna ex201, the demultiplexing unit ex308 separates the multiplexed data into a bit stream of image data and a bit stream of audio data, and synchronizes them. The encoded image data is supplied to the image decoding unit ex309 via the bus ex313, and the audio data is supplied to the audio processing unit ex305.

  Next, the image decoding unit ex309 is configured to include the moving image decoding apparatus described in the present invention, and a bit stream of image data is decoded by a decoding method corresponding to the encoding method described in the above embodiment. Reproduction moving image data is generated by decoding, and this is supplied to the display unit ex202 via the LCD control unit ex302, thereby displaying, for example, moving image data included in the moving image file linked to the homepage. . At the same time, the audio processing unit ex305 converts the audio data into analog audio data, and then supplies the analog audio data to the audio output unit ex208. Thus, for example, the audio data included in the moving image file linked to the home page is reproduced. The

  Note that the present invention is not limited to the above system, and recently, satellite and terrestrial digital broadcasting has become a hot topic, and as shown in FIG. Any of the video decoding devices can be incorporated. Specifically, in the broadcasting station ex409, a bit stream of video information is transmitted to a communication or broadcasting satellite ex410 via radio waves. Receiving this, the broadcasting satellite ex410 transmits a radio wave for broadcasting, and receives the radio wave with a home antenna ex406 having a satellite broadcasting receiving facility, such as a television (receiver) ex401 or a set top box (STB) ex407. The device decodes the bitstream and reproduces it. In addition, the moving picture decoding apparatus described in the above embodiment can also be implemented in a playback apparatus ex403 that reads and decodes a bitstream recorded on a storage medium ex402 such as a CD or DVD as a recording medium. . In this case, the reproduced video signal is displayed on the monitor ex404. A configuration is also possible in which a moving picture decoding apparatus is mounted in a set-top box ex407 connected to a cable ex405 for cable television or an antenna ex406 for satellite / terrestrial broadcasting, and this is reproduced on a monitor ex408 on the television. At this time, the moving picture decoding apparatus may be incorporated in the television instead of the set top box. It is also possible to receive a signal from the satellite ex410 or the base station ex107 by the car ex412 having the antenna ex411 and reproduce a moving image on a display device such as the car navigation ex413 that the car ex412 has.

  Furthermore, the image signal can be encoded by the moving image encoding apparatus shown in the above embodiment and recorded on a recording medium. As a specific example, there is a recorder ex420 such as a DVD recorder that records an image signal on a DVD disk ex421 or a disk recorder that records on a hard disk. Further, it can be recorded on the SD card ex422. If the recorder ex420 includes the moving picture decoding apparatus shown in the above embodiment, the image signal recorded on the DVD disc ex421 or the SD card ex422 can be reproduced and displayed on the monitor ex408.

For example, the configuration of the car navigation ex413 may be a configuration excluding the camera unit ex203, the camera interface unit ex303, and the image encoding unit ex312 in the configuration illustrated in FIG. 17, and the same applies to the computer ex111 and the television (receiver). ) Ex401 can also be considered.
In addition to the transmission / reception type terminal having both the encoder and the decoder, the terminal such as the mobile phone ex114 has three mounting formats: a transmitting terminal having only an encoder and a receiving terminal having only a decoder. Can be considered.

As described above, the moving picture encoding method or the moving picture decoding method described in the above embodiment can be used in any of the above-described devices and systems, and as a result, the above-described embodiment has been described. An effect can be obtained.
In addition, the present invention is not limited to the above-described embodiment, and various changes and modifications can be made without departing from the scope of the present invention.

  As described above, the moving image encoding method and the moving image decoding method according to the present invention encode an encoded stream by encoding each picture constituting a moving image using, for example, a mobile phone, a DVD device, and a personal computer. This is useful as a method for generating or decoding a generated encoded stream.

1 is a block diagram (Embodiment 1) showing a configuration of a moving picture encoding apparatus of the present invention. FIG. It is a figure (Embodiment 1) explaining the concept of the moving image decoding method of this invention. It is a block diagram (Embodiment 1) which shows the structure of the moving image decoding apparatus of this invention. FIG. 5 is an operation flowchart (Embodiment 1) of the moving picture decoding method of the present invention. FIG. 11 is an operation flowchart of the free space securing process of the video decoding method of the present invention (Embodiment 1). It is a block diagram (Embodiment 2) which shows the structure of the moving image decoding apparatus of this invention. FIG. 10 is an operation flowchart of the moving picture decoding method of the present invention (Embodiment 2). It is a figure which shows the structure of the data which the moving image encoding method of this invention outputs, and the structure of the data which the moving image decoding method of this invention inputs. It is a block diagram (Embodiment 3) which shows the structure of the moving image encoder of this invention. It is a figure (Embodiment 3) explaining the concept of the moving image encoding method of this invention. FIG. 10 is an operation flow diagram (Embodiment 3) of the moving picture encoding method of the present invention. It is a figure (Embodiment 4) explaining the concept of the moving image encoding method of this invention. FIG. 10 is an operation flowchart of the moving picture encoding method of the present invention (Embodiment 4). It is explanatory drawing about the recording medium for storing the program for implement | achieving the moving image encoding method and moving image decoding method of each embodiment by a computer system, (a) Of flexible disk which is a recording medium main body An explanatory diagram showing an example of a physical format, (b) an external view from the front of the flexible disk, a sectional structure, and an explanatory diagram showing the flexible disk, and (c) a configuration for recording and reproducing the program on the flexible disk FD It is explanatory drawing which showed. It is a block diagram which shows the whole structure of the content supply system which implement | achieves a content delivery service. It is a figure which shows an example of a mobile telephone. It is a block diagram which shows the internal structure of a mobile telephone. It is a block diagram which shows the whole structure of the system for digital broadcasting. It is a block diagram which shows the structure of the conventional moving image encoder. It is a figure explaining the concept of a display order (POC) and a referenced picture number. FIG. 10 is a diagram illustrating an operation of deleting a picture in order to secure a free area in a memory when there is a picture marked as unused. When there is no picture marked as unused, it is a figure explaining the operation | movement which erases a picture in order to ensure a vacant area in memory. It is a block diagram which shows the structure of the conventional moving image decoding apparatus. It is a flowchart of the operation | movement regarding the memory of the conventional moving image decoding apparatus. It is a flowchart of the operation | movement of the empty area ensuring process of the conventional moving image decoding apparatus. It is a conceptual diagram explaining the problem that the discontinuity of a sequence causes the discontinuity of display order information POC, and erase | eliminates an undisplayed picture. It is a conceptual diagram explaining operation | movement of an invalid picture. It is a block diagram which shows the structure of the conventional moving image decoding apparatus. It is a flowchart of operation | movement of the invalid picture of the conventional moving image decoding apparatus. It is a conceptual diagram explaining the problem that the discontinuity of the sequence causes the discontinuity of the frame number FN and the invalid picture erases the undisplayed picture. It is a conceptual diagram explaining the structure of the conventional MPEG-2 stream. It is a conceptual diagram explaining the moving image encoding method of the conventional JVT. It is an operation | movement flowchart of the moving image encoding method of the conventional JVT. It is a conceptual diagram explaining the problem which the freedom degree of encoding of JVT causes at the time of edit and random access.

Explanation of symbols

101 Reordering Memory 102 Encoding Scheduling Unit 103 Motion Detection Unit 104 Subtraction Operation Unit 105 Encoding Unit 106 Motion Compensation Unit 107 Variable Length Coding Unit 108 Decoding Unit 109 Addition Operation Unit 110, 111 Memory 112 Flag Information Generation Unit 113 Variable Long encoding unit 201, 213, 402, 411 Variable length decoding unit 202 Image decoding unit 203, 214 Edit detection unit 204 MMCO decoding unit 205, 212, 401, 412 Memory management unit 206 Memory 211 FN gap detection unit

Claims (5)

A video decoding method for decoding an encoded stream in units of pictures,
An information extraction step of extracting flag information indicating that the order of the pictures is discontinuous;
Look including a management step of managing the area for storing the decoded picture based on the flag information,
The flag information is information indicating that display order information of pictures is discontinuous,
In the management step, based on the display order information and the flag information, a picture having the earliest display order among decoded pictures stored in the area is determined, and the determined picture is to be deleted A moving picture decoding method characterized by being a picture . In the management step, clip information to be updated when the flag information is extracted is given to a decoded picture stored in the area, and the area is determined based on the display order information and the clip information. most previous picture to determine a, determined moving picture decoding method according to claim 1, characterized in that the deletion target picture picture display order among the decoded pictures stored. The moving picture decoding method further includes:
An invalid picture storage step of storing an invalid picture in the area when the coding order information of a picture is discontinuous,
The flag information is information indicating that the coding order information is discontinuous,
In the management step, it is determined whether to store an invalid picture in the area based on the flag information and the coding order information,
Wherein in the invalid picture storage step, the moving picture decoding method according to claim 1, wherein the storing invalid picture on the region on the basis of a determination result in the management step. A video decoding device that decodes an encoded stream in units of pictures,
Information extracting means for extracting flag information indicating that the order of the pictures is discontinuous;
Management means for managing an area for storing decoded pictures based on the flag information ,
The flag information is information indicating that display order information of pictures is discontinuous,
The management means determines the picture with the earliest display order among the decoded pictures stored in the area based on the display order information and the flag information, and deletes the determined picture to be deleted A moving picture decoding apparatus characterized by being a picture . A program for decoding an encoded stream in units of pictures,
A program for causing a computer to execute the steps according to claim 1 .

Images