JP2015065528A - Picture editing device, picture editing method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problems that encoded data cannot correctly be reproduced if a RASL picture exists in a connection section when the encoded data is cut in a scene unit with a RAP picture as a reference, and that the RASL picture which cannot be decoded is left in a bit stream after editing, thereby a file size unnecessarily increases.SOLUTION: An editing device edits encoded data obtained by encoding a moving picture including an access picture which allows random access. The editing device includes: division means for dividing the moving picture into a first picture group whose reproduction order is earlier than the access picture and a second picture group whose reproduction order is equal to or later than the access picture, when an instruction to perform reproduction starting from the middle of the moving picture is acquired; and generation means, when a predetermined picture encoded by referring to the first picture group is included in the second picture group divided by the division means, for generating a third picture group by excluding the predetermined picture from the second picture group.

Description

  The present invention relates to an image editing apparatus, an image editing method, and a program for editing an image encoded by a moving image compression encoding method.

  As an encoding method used for compression recording of moving images, H.264 is used. H.264 / MPEG-4 AVC (hereinafter referred to as H.264) is known (Non-Patent Document 1). Furthermore, in recent years, H.C. As a successor to H.264, an activity for international standardization of a more efficient coding scheme was started, and JCT-VC (Joint Collaborative Team on Video Coding) was established between ISO / IEC and ITU-T. In JCT-VC, H.C. The standardization of H.265 / High Efficiency Video Coding Coding (hereinafter referred to as HEVC) is being promoted (Non-patent Document 2).

  In general, a moving image that has been compression-encoded (hereinafter referred to as “encoding”) is stored as a bit stream in a storage device such as a DVD, HDD, memory card, etc. Often used for broadcasting applications. In this case, a random access function is required for performing processing such as reproduction from an arbitrary scene, editing, and clipping not only from the beginning of a moving image.

  H. In H.264, in order to realize such random access, a picture type called IDR (Instantaneous Decoding Refresh) picture is defined. For example, Patent Document 1 and Patent Document 2 disclose a technique of using an IDR picture to cut out and edit an arbitrary scene from a moving image.

  In the case of using an IDR picture, a picture having a later encoding order than the IDR picture (hereinafter referred to as an encoding order. The encoding order is the same as the decoding order) is an encoding order higher than that of the IDR picture. Is prohibited from referring to the previous picture. That is, an IDR picture is a picture that can decode a picture that has been encoded later than the IDR picture without referring to information of a picture encoded before the IDR picture. As described above, a picture subsequent to the IDR picture in the encoding order can be normally decoded after decoding the IDR picture by making the information of the picture encoded before the IDR picture inaccessible. . For this reason, by using an IDR picture, random accessibility can be improved and reproduction or editing can be performed from any picture.

  However, when an IDR picture is frequently used in a moving image, the encoding performance is higher than when a picture (for example, a B picture or a P picture) that can refer to a picture whose encoding order is earlier than that of a decoding target picture is used. There was a problem that (image quality, etc.) deteriorated. This is because when a picture whose encoding order is later than an IDR picture is decoded, the reference is limited as described above, so that a picture whose encoding order is earlier than that IDR picture cannot be referred to. To do.

  Also, in HEVC, in order to realize random access, H.264 is used. Similarly to H.264, an IDR picture is defined. Further, in HEVC, a CRA (Clean Random Access) picture is defined as a new picture type for realizing random access in order to improve a decrease in coding efficiency, which is a problem of an IDR picture.

  The CRA picture is a picture in which the order of display (reproduction) (hereinafter referred to as display order) is earlier than the CRA picture, and also refers to the information of the picture whose encoding order is earlier than the CRA picture. It is possible to decode pictures after the CRA picture. That is, when a CRA picture is used, there are no restrictions on pictures that can be referred to when decoding a picture whose coding order is later than the CRA picture. On the other hand, when an IDR picture is used as described above, there are restrictions on pictures that can be referred to when decoding a picture whose coding order is later than the IDR picture. For this reason, encoding efficiency is improved when a CRA picture is used than when an IDR picture is used.

  Hereinafter, pictures (access images) for realizing random access, such as the IDR picture and the CRA picture described above, are referred to as RAP (Random Access Point) pictures. A RAP picture is a picture obtained by independently encoding only the RAP picture regardless of the preceding and following pictures. H. In coding schemes such as H.264 and HEVC, the I picture is used as a RAP picture that is used during reproduction of the coded data, editing of the coded data, error recovery, and the like. In HEVC, BLA (Broken Link Access) is defined as a RAP picture in addition to an IDR picture and a CRA picture.

  FIGS. 8A to 8D show usage examples of IDR pictures and CRA pictures. 8 (a) and 8 (b) show a case where a P picture that performs unidirectional prediction exists for every three pictures and a B picture that performs bidirectional prediction exists between each P picture, starting with an IDR picture. An example is shown in the display order. FIG. 8C is a diagram in which the example of the display order shown in FIG. 8A is arranged in the encoding order. FIG. 8D is a diagram in which the example of the display order shown in FIG. 8B is arranged in the encoding order. Each number 0 to 12 in FIG. 8 represents the display order of each picture after decoding (hereinafter, the picture number 3 is referred to as picture 3. The same applies even if the number changes). In addition, each arrow in FIGS. 8A to 8D indicates a reference relationship in inter-frame prediction. For example, the P picture of picture 3 refers to the IDR picture of picture 0, and the B pictures of picture 1 and picture 2 refer to the IDR picture of picture 0 and the P picture of picture 3. Also, the picture 9 in FIGS. 8A to 8D is a RAP picture, the picture 9 in FIG. 8A is an IDR picture, and the picture 9 in FIG. 8B is a RAP picture. A CRA picture is used as a picture.

  In HEVC, a picture that has a coding order after the RAP picture and has a display order before the RAP picture is referred to as a leading picture. 8A to 8D, the B pictures of the picture 7 and the picture 8 are later in the encoding order than the RAP picture of the picture 9, and are in the display order earlier than the RAP picture. Therefore, the B pictures of the picture 7 and the picture 8 are leading pictures corresponding to the RAP picture of the picture 9.

  When an IDR picture is used as the RAP picture, the leading picture corresponding to the IDR picture is referred to as a RADL (Random Access Decoding Leading) picture. That is, the RADL picture is a picture that has a coding order after the IDR picture and has a display order before the IDR picture. For example, in FIG. 8A, picture 7 and picture 8 are RADL pictures. Pictures 7 and 8 are decodable pictures because they do not refer to pictures preceding the IDR picture (picture 9) in the coding order. In this way, the RADL picture can be decoded with reference to only the pictures subsequent to the IDR picture in the coding order.

  On the other hand, when a CRA picture is used as the RAP picture, the leading picture corresponding to the CRA picture is referred to as a RASL (Random Access Skipped Leading) picture. That is, the RASL picture is a picture that is later in coding order than the CRA picture and is earlier in display order than the CRA picture. For example, in FIG. 8B, picture 7 and picture 8 are RASL pictures. Since the pictures 7 and 8 refer to the picture 6 that is the previous picture in the coding order from the CRA picture (picture 9), when decoding is started from the CRA picture (picture 9), it is impossible to decode and it is necessary to skip the reading. It is a certain picture. Thus, a RASL picture cannot be decoded when referring to a picture preceding the CRA picture in the coding order.

JP 2007-67842 A JP 2011-23772 A

ITU-TH. H.264 (03/2010) Advanced video coding for generic audiovisual services JCT-VC Contribution JCTVC-K1003 Internet <http: // phenix. int-evry. fr / jct / doc_end_user / documents / 11_Shanghai / wg11 />

  As described above, when a CRA picture is used as a RAP picture in HEVC, a RASL picture that is a leading picture corresponding to the CRA picture refers to a previous picture in the coding order from the CRA picture. For this reason, decoding cannot be performed when decoding is started from the CRA picture. In other words, when coding data is edited and cut out from a moving image in units of scenes based on CRA pictures, if there is a RASL picture referenced across scenes, the RASL picture cannot be decoded and reproduced correctly. For this reason, there is a problem that RASL pictures that cannot be decoded remain in the edited bitstream, and an unnecessary file size increases.

  In order to solve the problems described above, the moving image editing apparatus according to the present invention divides the encoded data of the moving image immediately before a predetermined random accessible picture, and stores the encoded data of the random accessible picture. Assigned to each picture of the second divided data, the first divided data that ends immediately before, the dividing means for generating the second divided data starting from the encoded data of the randomly accessible picture, and the second divided data The attribute information is analyzed, and if the picture is encoded with reference to any picture included in the first divided data, it is determined that the picture is discarded, and otherwise, the picture is determined not to be discarded. And if there is a picture determined to be discarded by the determining means, discard the encoded data of the picture determined to be discarded, Combines the encoded data with each other pictures included in the second divided data is determined not to destroy the al, characterized in that it comprises generation means for generating a third divided data.

  According to the present invention, when a RASL picture is included in encoded data obtained by encoding a moving image, an unnecessary increase in file size can be suppressed without leaving a picture that cannot be decoded.

1 is a block diagram illustrating a configuration of an image editing apparatus according to a first embodiment. The flowchart which shows the determination flow in the determination part 101 of Embodiment 1 and Embodiment 2. FIG. The figure showing the example of a picture structure of the coding data of Embodiment 1. FIG. 3 is a block diagram illustrating a configuration of an image editing apparatus according to a second embodiment. The flowchart which shows the processing flow in the header change part 202 of Embodiment 2. FIG. The figure showing the example of a picture structure of the coding data of Embodiment 2. The figure showing the example of a picture structure of the coding data of Embodiment 2. The figure which shows the usage example of an IDR picture and a CRA picture

(Embodiment 1)
An image editing apparatus according to the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram illustrating a configuration of an image editing apparatus 10 according to the present embodiment. The data dividing unit 100 divides the encoded moving image data (hereinafter, encoded data) into first divided data (first image group) and second divided data (second image group). , Respectively. The determination unit 101 receives the second divided data output from the data dividing unit 100, and determines whether or not to discard the encoded data of each picture constituting the input second divided data. Further, the determination unit 101 outputs the determination result to the data generation unit 102. Based on the determination result output from the determination unit 101, the data generation unit 102 discards the encoded data determined to be discarded by the determination unit 101 among the second divided data output by the data division unit 100, Third divided data (third image group) is generated and output.

  Next, details of an operation for each processing unit of the image editing apparatus 10 shown in FIG. 1 to edit the encoded data will be described. In the present embodiment, it is assumed that the encoded data input to the data dividing unit 100 is encoded by the HEVC encoding method. Further, a RAP picture (hereinafter referred to as RAP1) as an access image that can be randomly accessed is a predetermined picture designated from the outside of the image editing apparatus 10. When the image editing apparatus 10 obtains an instruction from the outside of the image editing apparatus 10 to reproduce from the RAP 1 in the middle of the encoded data of the input moving image, the image editing apparatus 10 performs an editing process on the encoded data.

  When an acquisition unit (not shown) in the image editing apparatus 10 acquires an instruction to reproduce from the RAP1 from the outside of the image editing apparatus 10, the data dividing unit 100 displays the input encoded data immediately before RAP1. Dividing into first division data and second division data as division points. In other words, the first divided data is encoded data that precedes RAP1 in the encoding order. The second divided data is encoded data subsequent to RAP1 in the encoding order. RAP1 is included in the second divided data. That is, the first picture in the coding order in the second divided data is RAP1. Then, the data dividing unit 100 outputs the first divided data and the second divided data.

  Here, in the present embodiment, an example of the picture configuration of the encoded data input to the data dividing unit 100 will be described with reference to FIG. In FIG. 8D, when the picture 9 is the predetermined RAP1, the data dividing unit 100 recognizes the point between the picture 5 and the picture 9 (RAP1) as a dividing point. Then, the data division unit 100 outputs the encoded data before the picture 9 as the first divided data, and outputs the encoded data after the picture 9 as the second divided data. That is, in FIG. 8D, the first divided data is composed of pictures 0, 3, 1, 2, 6, 4, and 5, and the second divided data is pictures 9, 7, 8, It consists of 12, 10, and 11 pictures.

  The determination unit 101 analyzes attribute information given to each picture of the second divided data output by the data dividing unit 100, determines whether to discard the encoded data of each picture, and The determination result is output to the data generation unit 102. The determination unit 101 analyzes whether each picture of the second divided data is encoded with reference to any picture included in the first divided data divided by the data dividing unit 100. To do. Then, when the determination unit 101 analyzes that the determination target picture refers to any picture included in the first divided data, the determination unit 101 determines to discard the determination target picture. If the determination unit 101 analyzes that the determination target picture does not refer to any of the pictures included in the first divided data, the determination unit 101 determines not to discard the determination target picture.

  FIG. 2 is a diagram illustrating a determination flow of each picture in the determination unit 101. Hereinafter, the determination flow in the determination unit 101 will be described with reference to FIG.

  First, in step S <b> 200, the determination unit 101 captures attribute information given to the determination target picture from the second divided data output by the data division unit 100. Note that the determination unit 101 captures each picture in the encoding order from the input second divided data.

  Next, in step S201, the determination unit 101 analyzes the attribute information (picture type) of the determination target picture captured in step S200. If it is determined in step S201 that the determination target picture is a RASL (Random Access Skipped Leading) picture, the determination unit 101 proceeds to the process of step S202. If it is determined in step S201 that the determination target picture is not a RASL picture, the determination unit 101 proceeds to the process of step S203.

  In step S202, the determination unit 101 determines whether or not the determination target picture is a leading picture corresponding to the first RAP picture in the encoding order of the second divided data. If the picture to be determined is the leading picture corresponding to the first RAP, the process proceeds to step S204, and if not, the process proceeds to step S203.

  In step S203, the determination unit 101 determines not to discard the determination target picture. On the other hand, in step S204, the determination unit 101 determines to discard the determination target picture.

  Further, in step S205, the determination unit 101 determines whether the determination target picture is the last picture of the second divided data. If the determination target picture is the last picture, the determination process ends. If not, the process returns to step S200, and the attribute information of the next picture is captured. Thereafter, the same processing is performed, and the above processing is repeated until the determination of the last picture of the second divided data is completed.

  Here, an example of determination processing by the determination unit 101 in the present embodiment will be described with reference to FIG. The encoded data shown in FIG. 8D is data including a RASL picture. Hereinafter, an operation of the determination unit 101 when encoded data including a RASL picture as illustrated in FIG. 8D is input will be described.

  As described above, in the picture configuration shown in FIG. 8D, the second divided data is made up of pictures 9, 7, 8, 12, 10, and 11. Of these second divided data, picture 7 and picture 8 are leading pictures corresponding to picture 9 which is a CRA (Clean Random Access) picture. That is, picture 7 and picture 8 are RASL pictures. For this reason, when the pictures to be determined are the picture 7 and the picture 8 in step S201, the determination unit 101 determines YES. Furthermore, since these pictures 7 and 8 are the leading pictures corresponding to the first RAP picture (picture 9) in the encoding order of the second divided data, the determination unit 101 determines YES in step S202. . In step S204, the determination unit 101 determines that the picture 7 and the picture 8 are discarded pictures.

  Note that the picture determined to be discarded in step S204 indicates that any picture included in the first divided data is referenced. In addition, since all the pictures other than picture 7 and picture 8 in the second divided data are determined not to be RASL pictures (NO) in step S201 by the determination unit 101, it is determined not to discard these pictures in step S203. Is done. As a result, the determination unit 101 determines that the picture 7 and the picture 8 are discarded, and that the second divided data is a picture other than the picture 7 and the picture 8 that is not discarded, and outputs a determination result.

  The data generation unit 102 discards the encoded data of the picture determined to be discarded by the determination unit 101 among the second divided data output by the data dividing unit 100, and encodes the picture determined not to be discarded The data is combined to generate the third divided data. Then, the determination unit 101 outputs the generated third divided data.

  FIG. 3 is a diagram illustrating an example of the picture configuration of the second divided data output by the data dividing unit 100 and the encoded data output from the data generation unit 102 corresponding to the second divided data. It is. FIG. 3A shows the second divided data output by the data dividing unit 100, which is divided by the data dividing unit 100 based on the encoded data having the picture configuration shown in FIG. 8D. This corresponds to the data output as the second divided data. 3B illustrates an example of encoded data output from the data generation unit 102 when the encoded data of the second divided data illustrated in FIG. 3A is input to the data generation unit 102. Is shown.

  The data generation unit 102 discards the picture 7 and the picture 8 determined to be discarded by the determination unit 101 among the second divided data illustrated in FIG. Then, the data generation unit 102 connects the pictures positioned before and after the pictures 7 and 8 to generate and output third divided data. As a result, the third divided data is configured in the order of pictures 9, 12, 10, and 11, as shown in FIG.

  Note that it is necessary to provide a special mechanism on the decoder side in order to process the encoded data edited by the image editing apparatus in the present embodiment with the reproduction order properly maintained on the decoder side. For example, it is conceivable to provide the decoder with an interface for inputting a signal indicating whether or not editing as described above has been performed on the encoded data input to the decoder. On the decoder side, if the input encoded data indicates that it has been edited according to the signal, the number indicated by the POC of each picture has a missing number (in the above example, 7, 8). Can be achieved by configuring the display in ascending order.

  As described above, the operation of the image editing apparatus 10 has been described, including the case where the RASL picture exists in the encoded data input to the data dividing unit 100 as illustrated in FIG. Hereinafter, the operation of the image editing apparatus 10 will be described with reference to FIG. 8C for an example in which the RASL picture is not included in the encoded data input to the data dividing unit 100.

  In FIG. 8C, when the picture 9 is the predetermined RAP1, the data dividing unit 100 recognizes the division point between the picture 5 and the picture 9 (RAP1) as in FIG. 8D described above. To do. Then, the data division unit 100 outputs the encoded data before the picture 9 as the first divided data, and outputs the encoded data after the picture 9 as the second divided data. That is, in FIG. 8C, the first divided data is composed of pictures 0, 3, 1, 2, 6, 4, and 5, and the second divided data is pictures 9, 7, 8, It consists of 12, 10, and 11 pictures.

  Of these second divided data, picture 7 and picture 8 are leading pictures corresponding to picture 9 which is an IDR (Instantaneous Decoding Refresh) picture. That is, picture 7 and picture 8 are RADL pictures. For this reason, when the pictures to be determined are picture 7 and picture 8, the determination unit 101 determines in step S201 that the picture is not a RASL picture (NO). Also, the determination unit 101 determines that all the pictures other than the pictures 7 and 8 in the second divided data are not RASL pictures in step S201 (NO). As a result, the determination unit 101 determines that all the pictures of the second divided data including the pictures 7 and 8 are not discarded in step S203, and outputs a determination result.

  Based on the determination result output by the determination unit 101, the data generation unit 102 does not discard any picture of the second divided data output by the data division unit 100, and uses the second divided data as it is. Output as third divided data. Note that the first divided data output from the data dividing unit 100 and the third divided data output from the data generating unit 102 are discarded or combined with other encoded data as necessary. Can be used as appropriate.

  Further, in the present embodiment, the transmission unit (not shown) of the image editing apparatus 10 images the first divided data output from the data dividing unit 100 and the third divided data output from the data generating unit 102. The data is transmitted to the outside of the editing apparatus 10 via the network. The image editing apparatus 10 of the present invention is not limited to this, and the first divided data and the third divided data are recorded from the image editing apparatus 10 to a memory (not shown), and the memory to the decoding apparatus via a bus. May be configured to transmit. In this way, by transmitting the first divided data and the third divided data that do not include a picture (encoded data) that cannot be decoded (which cannot be decoded), the second divided data is transmitted as in the related art. Rather, the file size of the encoded data to be transmitted can be reduced. For this reason, the processing load of the transmission part which transmits the said encoding data, and the processing load of the receiver (not shown) which receives the said encoding data can be reduced.

  As described above, the image editing apparatus according to the present embodiment determines that reproduction is not possible when the input encoded data includes a RASL picture and the RASL picture is divided as a division point. The picture can be discarded. For this reason, it can be avoided that unnecessary pictures (encoded data) that cannot be decoded exist in the file, and an increase in unnecessary file size can be suppressed.

(Embodiment 2)
In the first embodiment, the image editing apparatus including the data dividing unit 100, the determining unit 101, and the data generating unit 102 has been described. In the present embodiment, an image editing apparatus that further includes a header changing unit 202 will be described.

  Hereinafter, the image editing apparatus according to the present embodiment will be described with reference to FIG. FIG. 4 is a block diagram illustrating the configuration of the image editing apparatus 10 according to the present embodiment. In the present embodiment, the data dividing unit 100 and the determination unit 101 shown in FIG.

  The header changing unit 202 inputs the second divided data output by the data dividing unit 100 and the determination result output by the determining unit 101. Then, the header changing unit 202 changes the header information in each picture of the second divided data based on the input second divided data and the determination result, and the second divided data in which the header information is changed is stored as data. The data is output to the generation unit 203.

  Based on the determination result output by the determination unit 101, the data generation unit 203 discards data as necessary from the second divided data output by the data division unit 100, and combines the pictures determined not to be discarded. Encoded data is generated. Further, the data generation unit 203 replaces the header information based on the output of the header change unit 202. Then, the data generation unit 203 generates third divided data using the encoded data generated by combining and the replaced header information, and outputs the third divided data to the subsequent stage.

  Next, details of an operation for each processing unit of the image editing apparatus 10 shown in FIG. 4 to edit the encoded data will be described. In the present embodiment, similarly to the first embodiment, the encoded data input to the data dividing unit 100 is described as being encoded by the HEVC encoding method.

  First, in the present embodiment, an example in which the encoded data input to the data dividing unit 100 has the picture configuration shown in FIG. 8D, that is, a case where a RASL picture exists in the input encoded data will be described. To do. In this case, as in the first embodiment, the data dividing unit 100 includes first divided data composed of 0, 3, 1, 2, 6, 4 and 5 pictures, and 9, 7, 8, 12 2nd division data comprised from each picture of 10 and 11 is output.

  The determination unit 101 analyzes attribute information given to each picture of the second divided data output by the data dividing unit 100, determines whether to discard the encoded data of each picture, and The determination result is output to the header changing unit 202 and the data generating unit 203. Note that the determination flow in the determination unit 101 and the operation of the determination unit 101 in the picture configuration example shown in FIG.

  When the picture type of RAP1 included in the second divided data output by the data dividing unit 100 is CRA, the header changing unit 202 changes the picture type to IDR. Note that, in a CRA picture, it is impossible to decode a picture included in the second divided data that refers to a picture whose coding order is earlier than that of the CRA picture. On the other hand, in an IDR picture, a picture whose coding order is earlier than that of the IDR picture is not a reference target, and therefore it is possible to perform decoding with reference to only a picture included in the second divided data. Therefore, when the RAP1 picture type included in the second divided data is CRA, the header changing unit 202 changes only the picture included in the second divided data by changing the picture type to IDR. It can be decoded with reference.

  Also, the header changing unit 202 (setting unit) resets information (POC: Picture Order Count) indicating the coding order of the RAP1. Then, the header changing unit 202 considers the picture determined to be discarded by the determining unit 101 based on the determination result output by the determining unit 101, and the POC of the picture following the picture determined to be discarded Renumbering accordingly. Further, the header changing unit 202 outputs the changed header information to the data generating unit 203.

  Here, the header change flow in the header change unit 202 is shown in FIG. Hereinafter, the header change flow in the header change unit 202 will be described with reference to FIG.

  First, in step S500, the header changing unit 202 determines whether the first picture of the second divided data output from the data dividing unit 100, that is, the picture type of RAP1 is CRA by analyzing the header information of the picture. To do. If the header changing unit 202 determines that the picture type of RAP1 is CRA (YES in step S500), the process proceeds to step S501. If the header changing unit 202 determines that the picture type of RAP1 is not CRA (NO in step S500), Processing ends.

  Next, in step S501, the header changing unit 202 changes the header information so that the picture type of the first picture (RAP1) is changed from CRA to IDR. In step S502, the header changing unit 202 resets POC, which is information indicating the playback order of the RAP1, to 0. Further, in step S503, the header changing unit 202, among the second divided data, is a picture other than the picture determined to be discarded by the RAP1 and the determining unit 101, and all the pictures up to immediately before the next IDR picture. Renumber the POCs.

  Returning to the description of each processing unit in FIG. The data generation unit 203 discards the encoded data of the picture determined to be discarded by the determination unit 101 among the second divided data output by the data dividing unit 100, and the remaining pictures determined not to be discarded. The combined encoded data is generated. Further, the data generation unit 203 replaces the header information included in the second divided data output from the data dividing unit 100 based on the header information output by the header changing unit 202. Then, the data generation unit 203 generates third divided data using the encoded data generated by combining and the replaced header information, and outputs the third divided data to the subsequent stage.

  FIG. 6 illustrates an example of the picture configuration of the second divided data output from the data dividing unit 100 and the encoded data output from the data generation unit 102 corresponding to the second divided data. It is a figure. FIG. 6A shows the second divided data output by the data dividing unit 100, which is divided by the data dividing unit 100 based on the encoded data having the picture configuration shown in FIG. 8D. This corresponds to the data output as the second divided data. The numbers shown at the bottom of each picture indicate the POC of each picture. In the example of FIG. 6, it is assumed that the picture type of the first picture (RAP1) is CRA, and the pictures determined to be discarded by the determination unit 101 are the pictures 7 and 8.

  In this case, the header changing unit 202 determines YES in step S500 of FIG. 5 because the picture type of the first picture is CRA. Next, in step S501, the header changing unit 202 changes the header information so that the picture type of the first picture is IDR. In step S502, the header changing unit 202 resets POC, which is information indicating the reproduction order of the first picture, to 0. In step S503, the header changing unit 202 renumbers the POCs of the picture 12, the picture 10, and the picture 11. Here, FIG. 6B shows a picture configuration after the change (renumbering). In this case, as shown in FIG. 6B, the POCs of the pictures 12, 10 and 11 are changed to 3, 1, and 2, respectively.

  The data generation unit 203 discards the pictures 7 and 8 determined to be discarded by the determination unit 101 among the second divided data illustrated in FIG. Then, the data generation unit 203 generates encoded data obtained by connecting the pictures located before and after the picture 7 and the picture 8. Then, the data generation unit 203 generates and outputs the third divided data using the changed header information received from the header changing unit 202 and using the combined header data and the encoded data generated by combining. . As a result, the third divided data is configured in the order of pictures 0, 3, 1, 2 as shown in FIG.

  As described above, the editing operation of the encoded data has been described for the example in which the RASL picture exists in the encoded data input to the data dividing unit 100. However, if the RASL picture does not exist in the input encoded data, more Simple operation.

  Hereinafter, an example in which the encoded data input to the data dividing unit 100 has the picture configuration illustrated in FIG. 8C, that is, the case where no RASL picture exists in the input encoded data will be described. In this case, the data dividing unit 100 includes first divided data composed of 0, 3, 1, 2, 6, 4 and 5 pictures, and 9, 7, 8, 12, 10 and 11 pictures. 2nd division data comprised from this is output.

  The determination unit 101 analyzes attribute information given to each picture of the second divided data output by the data division unit 100, determines whether to discard the encoded data of each picture, and determines The result is output to the subsequent stage. Here, the determination unit 101 does not discard all the pictures of the second divided data because the second divided data output by the data dividing unit 100 has the picture configuration shown in FIG. It is determined as a picture, and the determination result is output.

  Here, since the determination unit 101 determines that the header changing unit 202 does not discard all the pictures of the second divided data, the header changing unit 202 sets the POC of the first picture (RAP1) to 0 and sets the first picture and the subsequent pictures. The POC of the picture is changed accordingly.

  Here, the data generation unit 203 determines that the determination unit 101 does not discard all the pictures of the second divided data, so the second divided data output from the data division unit 100 and the header change unit 202 Third divided data is generated using the output header information.

  FIG. 7 shows an example of the picture configuration of the second divided data output by the data dividing unit 100 and the encoded data output from the data generation unit 102 corresponding to the second divided data. It is a figure. FIG. 7A shows the second divided data output by the data dividing unit 100, which is divided by the data dividing unit 100 based on the encoded data having the picture configuration shown in FIG. 8C. This corresponds to the data output as the second divided data. The numbers shown at the bottom of each picture indicate the POC of each picture, as in FIG. In the example of FIG. 7, it is assumed that the picture type of the first picture (RAP1) is CRA, and no picture determined to be discarded by the determination unit 101 exists.

  In this case, the header changing unit 202 determines YES in step S500 of FIG. 5 because the picture type of the first picture is CRA. Next, in step S501, the header changing unit 202 changes the header information so that the picture type of the first picture is IDR. In step S502, the header changing unit 202 resets POC, which is information indicating the reproduction order of the first picture, to 0. Next, in step S503, the header changing unit 202 renumbers the POCs of the picture 7, the picture 8, the picture 12, the picture 10, and the picture 11. Here, FIG. 7B shows a picture configuration after the change (renumbering). In this case, as shown in FIG. 7B, the POC of each picture 7, 8, 12, 10 and 11 is changed to -2, -1, 3, 1, 2 respectively.

  Since there is no picture determined to be discarded by the determination unit 101, the data generation unit 203 does not discard any of the second divided data illustrated in FIG. Then, the data generation unit 203 generates and outputs the third divided data by using the header information after replacement with the changed header information received from the header changing unit 202, and using the second divided data and the replaced header information. As a result, the third divided data is configured in the order of pictures-2, -1, 3, 1, 2 as shown in FIG.

  As in the first embodiment, in the present embodiment, the first divided data output from the data dividing unit 100 and the third divided data output from the data generating unit 102 are discarded as necessary. Or combined with other encoded data for appropriate use.

  Further, in the present embodiment, the transmission unit (not shown) of the image editing apparatus 10 images the first divided data output from the data dividing unit 100 and the third divided data output from the data generating unit 102. The data is transmitted to the outside of the editing apparatus 10 via the network. The image editing apparatus 10 of the present invention is not limited to this, and the first divided data and the third divided data are recorded from the image editing apparatus 10 to a memory (not shown), and the memory to the decoding apparatus via a bus. May be configured to transmit. In this way, by transmitting the first divided data and the third divided data that do not include a picture (encoded data) that cannot be decoded (which cannot be decoded), the second divided data is transmitted as in the related art. Rather, the file size of the encoded data to be transmitted can be reduced. For this reason, the processing load of the transmission part which transmits the said encoding data, and the processing load of the receiver (not shown) which receives the said encoding data can be reduced.

  As described above, the image editing apparatus according to the present embodiment determines that reproduction is not possible when the input encoded data includes a RASL picture and the RASL picture is divided as a division point. The picture can be discarded. For this reason, it can be avoided that unnecessary pictures (encoded data) that cannot be decoded exist in the file, and an increase in unnecessary file size can be suppressed.

  Furthermore, in the image editing apparatus according to the present embodiment, when a CRA picture exists near the cut-out point (first cut-out picture), the picture after the IDR picture is decoded by replacing the picture with the IDR picture. can do.

  Also, as described above, when a CRA picture exists near the cut-out point, the playback order on the decoder side can be kept appropriate by resetting the POC information. In the first embodiment described above, a special mechanism such as inputting that the data has been edited to the decoder side is necessary to ensure that the reproduction order is properly maintained on the decoder side. This mechanism is not necessary for decoding the generated encoded data.

(Other embodiments)
In each of the above-described embodiments, after the first divided data and the second divided data are divided by the data dividing unit 100, the second divided data is processed by each processing unit to obtain the third divided data. However, the present invention is not limited to this. That is, in the first embodiment, among the encoded data of the moving image input to the image editing apparatus 10, the data after RAP1 in the encoding order is a picture that cannot be reproduced by the processing of the determination unit 101 and the data generation unit 102. Any data can be used as long as it can generate data that does not include. Similarly, in the second embodiment, among the encoded data of the moving image input to the image editing apparatus 10, the data after RAP1 in the encoding order cannot be reproduced by the processing of each processing unit 101, 202, 203. Any data may be used as long as it generates data that does not include a picture that becomes. By performing such a process, the process of dividing the first divided data and the second divided data by the data dividing unit 100 can be omitted.

  In each of the embodiments described above, the encoded data input to the data dividing unit 100 has been described as being encoded by the HEVC encoding method, but the present invention is not limited to this. In other words, any encoding method that can use a CRA picture is acceptable.

  In each of the above-described embodiments, description has been made using CRA as a RAP picture for enabling random access. However, the present invention is not limited to this. That is, when a picture subsequent to the RAP picture is encoded in the encoding order, a picture that has no reference limitation (can be encoded with reference to the previous picture in the encoding order from the RAP picture) is used. It doesn't matter.

  The present invention can also be realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiments is supplied to a system or apparatus via a network or various storage media, and a computer (or CPU, MPU, etc.) of the system or apparatus reads the program. It is a process to be executed.

Claims (13)

An editing device for editing encoded data obtained by encoding a moving image including an access image that enables random access,
When an instruction to reproduce from the middle of the moving image is acquired, the moving image is later in the reproduction order than the first image group whose reproduction order is earlier than the access image and the access image including the access image. Dividing means for dividing the image into a second image group,
When the predetermined image encoded with reference to the first image group is included in the second image group divided by the dividing unit, the predetermined image is extracted from the second image group. An image editing apparatus comprising: generating means for generating a third image group excluding images.   The image editing apparatus according to claim 1, further comprising a changing unit that rewrites a reproduction order of an image group obtained by removing the predetermined image from the second image group.   3. The image editing apparatus according to claim 1, wherein the picture type of the access image is a Clean Random Access. 4.   And changing means for changing the picture type of the access image to Instantaneous Decoding Refresh when the picture type of the access image whose playback order is the first image in the second image group is Clean Random Access. The image editing apparatus according to claim 1, further comprising: an image editing apparatus according to claim 1.   The image editing apparatus according to claim 1, further comprising setting means for setting information indicating an encoding order of the third image group.   6. The image editing apparatus according to claim 5, wherein the setting unit resets information indicating a coding order of the access image whose picture type has been changed to Instantaneous Decoding Refresh by the changing unit. And determining means for determining whether or not the predetermined image encoded with reference to the first image group is included in the second image group,
The determination unit determines to discard the leading picture when the picture type of the leading picture corresponding to the access image in the second image group is Random Access Skipped Leading, and the picture type of the leading picture is The image editing apparatus according to any one of claims 1 to 6, wherein the leading picture is determined not to be discarded when it is not random access skipped leading.   8. The image editing apparatus according to claim 7, wherein, when the picture type of the leading picture is Random Access Skipped Leading, data obtained by encoding the leading picture is data that cannot be decoded.   8. The leading picture corresponding to the access image is an image whose encoding order is later than that of the access image and whose playback order is earlier than that of the access image. The image editing apparatus described.   The image editing apparatus according to claim 1, further comprising a transmission unit that transmits the third image group generated by the generation unit. An image editing device for editing encoded data obtained by encoding a moving image including an access image that enables random access,
When an instruction to reproduce from the middle of the moving image is acquired, the image group of the moving image, the image group having a reproduction order later than the access image including the access image, When a predetermined image that is encoded with reference to an image whose playback order is earlier than the access image is included, an image group obtained by removing the predetermined image from the moving image is generated. An image editing apparatus comprising a generating unit. An image editing method of an image editing apparatus for editing encoded data obtained by encoding a moving image including an access image that enables random access,
A dividing step of dividing the moving image into a first image group whose playback order is earlier than the access image and a second image group whose playback order is later than the access image including the access image;
When the predetermined image encoded with reference to the first image group is included in the second image group divided by the dividing unit, the predetermined image is extracted from the second image group. An image editing method comprising: generating a third image group excluding images.   A program that causes the computer to function as the image editing apparatus according to claim 1 by being read and executed by the computer.

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