JP2008066852A - Information processor and information processing method, recording medium, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To securely record an insert-edited stream even if the remaining recording capacity of a recording medium is small. <P>SOLUTION: The number of clusters calculating unit calculates the numbers of clusters to be allocated to a stream C2 and a stream D2 in a re-encoding section from the number of clusters from a position α2 to a position δ2 of a stream A2 and the number of clusters from a position β2 to a position γ2 of a stream B2 inserted into the stream A2. A code amount calculating unit calculates a target code amount of re-encoding so that the streams C2 and D2 can be recorded in the respectively allocated number of clusters. An encoding control unit controls re-encoding of the stream C2 and stream D2 so that the code amount reaches the calculated code amount. The present invention is applicable to an editing device which edits an image. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an information processing apparatus and method, a recording medium, and a program, and more particularly to an information processing apparatus and method, a recording medium, and a program that are suitable for performing insert editing on compressed video data recorded on a recording medium.

  In an image compression method represented by MPEG (Moving Picture Coding Experts Group / Moving Picture Experts Group) or the like, high compression efficiency is realized by compressing and encoding a video signal using inter-frame prediction.

  For example, in MPEG, a compression coding method using bidirectional inter-frame prediction composed of an I picture, a P picture, and a B picture is called Long GOP (Group of Picture) compression.

  Here, an I picture is an intra-frame (Intra) coded image, which is a picture that is coded independently of other screens, and can be decoded only with this information. . A P picture is an inter-frame (inter) forward predictive encoded image, and is a forward predictive encoded picture represented by a difference from a temporally previous (forward) frame. A B picture is a bi-directional predictive encoded image, and is used between motion compensation frames using temporally forward (forward), backward (reverse), or forward / backward (bidirectional) pictures. It is a picture encoded by prediction.

  Conventionally, a method of cut editing a stream compressed (encoded) by the Long GOP method has been proposed. In such cut editing, as shown in FIG. 1, a stream A1 and a stream B1 are connected at an editing point. (See, for example, Patent Document 1).

  In the figure, Pa1 and Pb1 indicate edit points in the stream A1 and the stream B1, respectively. In the figure, the vertical line indicates a GOP break in each stream.

  In the example of FIG. 1, the part from the start position α1 of the GOP including the editing point Pa1 of the stream A1 to the editing point Pa1, and the editing point Pb1 of the stream B1 to the end position β1 of the GOP including the editing point Pb1. The parts are decoded and connected to form a stream C1. The stream C1 obtained by the connection is set as a re-encoding section, and the occupancy of the VBV (Video Buffering Verifier) buffer at the start position of the re-encoding section starts to change from the occupancy position at the position α1 of the stream A1. The re-encoding section is re-encoded so that the occupancy at the end position of the re-encoding section ends at the position of the occupancy at the position β1 of the stream B1.

  Then, the re-encoded stream C1 has a start position and an end position connected to a part before the position α1 of the stream A1 and a part after the position β1 of the stream B1, respectively, to form a stream D1. That is, the stream D1 including the code up to the section a1 and the section b1 of the stream A1, the code of the section d1 of the stream C1, and the code after the section c1 of the stream B1 is a stream obtained as a result of editing.

  By the way, the above-described cut editing technique is used to replace a predetermined section in a stream (hereinafter also referred to as background data) recorded on a recording medium with another stream (hereinafter referred to as overwrite data). Insert editing is known in which overwrite data is inserted into a predetermined section of data.

  In the insert editing, as shown in FIG. 2, a predetermined section of the stream B2, which is the overwrite data, is inserted into the stream A2, which is the background data, and the vicinity of the IN point and the OUT point where the stream B2 is inserted. The neighborhood is re-encoded as in cut editing. In the figure, vertical lines indicate the GOP breaks in each stream.

  In the example of FIG. 2, the section from the position IN3 to the position OUT3 of the stream B2 is inserted into the section from the position IN2 to the position OUT2 in the stream A2. At this time, the part from the start position α2 to the position IN2 of the GOP including the position IN2 and the part from the position IN3 of the stream B2 to the end position β2 of the GOP including the position IN3 are decoded and connected, and the stream C2 It is said.

  Similarly, the portion from the start position γ2 to the position OUT3 of the GOP including the position OUT3 of the stream B2 and the portion from the position OUT2 of the stream A2 to the end position δ2 of the GOP including the position OUT2 are decoded and connected. , Stream D2.

  Further, the stream C2 and the stream D2 are re-encoded, and the stream A2 and the stream B2 and the re-encoded stream C2 and the stream D2 are connected to be a stream E2.

  That is, the code of the section a2 up to the position α2 of the stream A2, the code of the section j2 of the stream C2, the section of the stream B2 from the position β2 to the position γ2, that is, the codes of the section g2, the section h2, and the section i2, and the stream D2 A stream E2 including the code of the section k2 and the code of the section f2 after the position δ2 of the stream A2 is a stream obtained as a result of the insert editing.

  In the following description, the position IN2 or the position IN3 is also referred to as an IN point, and the position OUT2 or the position OUT3 is also referred to as an OUT point.

  Insert editing that replaces a predetermined section of a stream recorded on such a recording medium with another stream is the same as when insert editing is performed on a moving image signal recorded on a VTR (Video Tape Recorder). The effect is obtained. In other words, even when the recording medium on which the background data is recorded does not have a recording capacity for recording other data, the other data is overwritten in the section to be edited of the background data, so that the data is recorded on the recording medium. The background data being edited can be edited.

  In many recording media, cluster management is performed when data is recorded on the recording medium. That is, in many recording media, a cluster of a specific size, which is a recording unit of the recording medium, is prepared for each recording medium or for each OS (Operating System) that controls the operation of a device that records data on the recording medium. The data to be recorded is divided into the cluster size and recorded on the recording medium. Here, the size of the cluster is, for example, a predetermined size of 1 Byte or more.

  For example, when a variable length encoded moving image file is recorded on a recording medium, each frame of the moving image file is divided into clusters and recorded for each frame. Therefore, only one frame of data is stored and recorded in one cluster.

JP 2006-67095 A

  However, since the code length of one frame of a moving image, that is, the size of each frame is not necessarily an integral multiple of the size of the cluster, a cluster gap is included in a cluster in which a moving image file on a recording medium is recorded. There is a cluster with

  Therefore, even if the data amount of the entire stream is equal to each other, if the frame design is different, the size of each frame is different, so the number of clusters having a cluster gap when recording these streams is also different, The number of clusters required for recording each stream on the recording medium, that is, the recording capacity is also different.

  For example, as shown in FIG. 3, when the stream P and the stream Q are recorded on the recording medium, the number of clusters required for recording the stream is different even if the code amount of the streams is the same.

  FIG. 3 shows each frame constituting stream P and stream Q, that is, the code amount of each picture and the number of clusters required for recording each picture, the code amount of stream P and stream Q, and the recording of those streams. The number of clusters required for each is shown. Note that the stream P and the stream Q have a picture rate of 30 Hz, a bit rate of 50 Mbps, the number of pictures in the GOP is 15, and an M value indicating an interval between I pictures or P pictures is 3, which is based on CBR (Constant Bit Rate). This is an encoded stream, and the size of one cluster in FIG. 3 is 2000 bytes.

  In the example of FIG. 3, the code amount of the leading picture I2 of the stream P is 10000000 bytes and the number of clusters is 5000. On the other hand, since the code amount of the leading picture I2 of the stream Q is 9999986 Bytes and the number of clusters is 5000, the code amount of the picture I2 of the stream Q is smaller than the code amount of the picture I2 of the stream P. However, the number of clusters required for recording is the same as the picture I2 of the stream P.

  In addition, for each of the pictures after the picture B0, that is, the pictures B0 to B13, the code amount of each picture is smaller by 1 byte than the stream Q, and the number of classes is also decreased by one.

  Further, each of the stream P and the stream Q has the same code amount of 25000000 bytes, but the number of clusters necessary for recording the stream P is 12,500, whereas the stream Q is recorded. The required number of clusters is 12,514, which is 14 more than in the stream P.

  Thus, even if the streams obtained by variable length coding are streams having the same data amount, the recording capacities required for recording on the recording medium are different. Therefore, when the insert editing described with reference to FIG. 2 is performed and overwrite data is overwritten in a predetermined section of the background data, the data amount of the background data section and the overwrite data is the same. However, since the size on the recording medium, that is, the number of clusters necessary for recording is generally different, the number of clusters necessary for recording the overwrite data is larger than the number of clusters in the section where the overwrite data is inserted in the base data. In some cases, it becomes impossible to insert overwrite data into the background data.

  That is, in FIG. 2, when each of stream A2 to stream D2 is a stream obtained by encoding by CBR, the occupancy of the VBV buffer is continuous and there is no period in which the bit rate is 0. The total code amount from the position α2 to the position δ2, that is, the total code amount from the section b2 to the section e2, and the total code amount from the section j2 to the section k2 in the stream E2 are the same. However, since the number of clusters required for recording is not necessarily the same, there is a possibility that the portion from the section j2 to the section k2 of the stream E2 cannot be overwritten on the portion from the position α2 to the position δ2 of the stream A2 on the recording medium. is there.

  Conventionally, when the number of clusters required for recording overwrite data is larger than the number of clusters in the portion where overwrite data is inserted in the background data and the background data cannot be rewritten to the overwrite data, the overwrite data is recorded on the recording medium. It was recorded in an area different from the area where the background data was recorded.

  Therefore, since the number of clusters required for recording the overwrite data is larger than the number of clusters of the background data, the background data cannot be rewritten to the overwrite data, and the overwrite data is not recorded on the recording medium on which the background data is recorded. If the recording capacity necessary for recording does not remain, the base data cannot be edited.

  In addition, a recording area for recording overwrite data in advance on the recording medium can be secured to some extent. However, the size of the recording area varies depending on the number of edits and the size of the overwrite data. It was difficult to ensure a large recording area.

  Furthermore, as a result of the insert editing, if the predetermined section of the background data on the recording medium cannot be rewritten to the overwrite data, and the overwrite data is recorded in an area different from the area where the background data is recorded, Since the overwrite data connected to a predetermined section of the background data is recorded at a position physically discontinuous from the position where the background data to be reproduced immediately before the overwrite data is recorded, When the part is reproduced, it is necessary to jump from the position where the background data to be reproduced immediately before the overwrite data is recorded to the position where the overwrite data is recorded and reproduce it.

  In such a case, depending on the conditions specific to the recording medium and the device that reproduces the data, a long time is required for the physical jump of the recording position, or a buffer for temporarily storing the data is required. Therefore, if a certain amount of delay caused by jumping or buffering is not allowed, a time limit is necessary for the reproduction section of the overwrite data inserted into the base data. In other words, it is necessary to reduce the reproduction time of the overwrite data, that is, the data amount so that the base data can be rewritten to the overwrite data.

  The present invention has been made in view of such a situation, and it is possible to reliably record an insert edited stream on a recording medium even when the recording capacity that can be recorded on the recording medium is small. To do.

  An information processing apparatus according to an aspect of the present invention sets a target code amount and re-encodes a second encoded stream in a predetermined section of the first encoded stream recorded on a recording medium. An information processing apparatus that performs a process from a first position before an IN point that is a start position of the predetermined section to a second position after an OUT point that is an end position of the predetermined section From the first cluster number required for recording the first encoded stream and the third position in the vicinity of the start position of the second encoded stream, the end position of the second encoded stream is determined. Video obtained by decoding the first encoded stream from the first position to the IN point using the second number of clusters required for recording up to the fourth position in the vicinity Of the signal and the second encoded stream A first video signal connected to a video signal obtained by decoding the second encoded stream from a start position to the third position, and the second code from the fourth position. Video signal obtained by decoding the second encoded stream up to the end position of the encoded stream and video obtained by decoding the first encoded stream from the OUT point to the second position A cluster number calculating means for calculating a third cluster number that can be used for recording the second video signal connected to the signal, and re-encoding the first video signal and the second video signal. , Using the re-encoding means for generating the first re-encoded stream and the second re-encoded stream, and the third cluster number calculated by the cluster number calculating means. A code amount calculating means for calculating a target code amount for re-encoding the signal and the second video signal, and a generated code amount obtained by re-encoding the first video signal and the second video signal. Re-encoding control means for controlling re-encoding by the re-encoding means so as to achieve the target code amount.

  The information processing apparatus includes the first re-encoded stream generated by the re-encoding unit, the second encoded stream from the third position to the fourth position, and the second re-encoded stream. Recording means for connecting the encoded streams and recording the first encoded stream from the first position to the second position on the recording medium at a position where the first encoded stream is recorded can be further provided. .

  The cluster number calculation means uses the third cluster number to use the fourth cluster number that can be used for recording the first video signal and the second video signal that is used for recording. A fifth number of clusters that can be obtained, and the code amount calculating means obtains a number obtained by subtracting a number that is one less than the number of pictures of the first video signal from the number of fourth clusters. The target code amount of the first video signal is calculated on the basis of the number of clusters of 6, and a number that is less by 1 than the number of pictures of the second video signal is subtracted from the fifth cluster number. The target code amount of the second video signal can be calculated based on the obtained seventh cluster number.

  The first encoded stream, the second encoded stream, the first re-encoded stream, and the second re-encoded stream may conform to the MPEG standard.

  The code amount calculation means calculates the occupancy of the VBV buffer at the first position and the occupancy of the VBV buffer at the third position from a value obtained by multiplying the sixth cluster number by the cluster size. A value obtained by subtracting the difference is calculated as the target code amount of the first video signal, and the fourth position is calculated from a value obtained by multiplying the seventh cluster number by the cluster size. The value obtained by subtracting the difference between the occupancy of the VBV buffer at the second position and the occupancy of the VBV buffer at the second position can be calculated as the target code amount of the second video signal.

  The code amount calculation means further calculates a bit rate when the first video signal is re-encoded using the target code amount of the first video signal, and the second video signal The bit rate when the second video signal is re-encoded can be calculated using the target code amount.

  The information processing apparatus obtains a first remaining cluster number that is a difference between the fourth cluster number and the number of clusters required for recording the first re-encoded stream, and the first remaining cluster number The number of clusters is allocated to each GOP constituting the first re-encoded stream, dummy data corresponding to the number of clusters allocated to each GOP is inserted at the end of those GOPs, and the fifth cluster number And a second remaining cluster number that is a difference between the number of clusters required for recording the second re-encoded stream, and the second remaining cluster number is determined as the second re-encoded stream. Further, it is possible to further provide insertion means for allocating dummy data corresponding to the number of clusters allocated to each GOP at the end of those GOPs.

  An information processing method or program according to one aspect of the present invention sets a target code amount when recording a second encoded stream in a predetermined section of a first encoded stream recorded on a recording medium. For executing information processing for performing re-encoding, from a first position before an IN point that is a start position of the predetermined section, from an OUT point that is an end position of the predetermined section From the first number of clusters required for recording the first encoded stream up to the second position after the second and the third position in the vicinity of the start position of the second encoded stream, the second The first encoded stream from the first position to the IN point using the second number of clusters required for recording up to the fourth position in the vicinity of the end position of the encoded stream of Video signal obtained by decoding And the first video signal obtained by decoding the second encoded stream from the start position of the second encoded stream to the third position, and the first video signal, 4 and the video signal obtained by decoding the second encoded stream from the position 4 to the end position of the second encoded stream, and the first encoding from the OUT point to the second position. A third cluster number that can be used for recording the second video signal connected to the video signal obtained by decoding the stream is calculated, and using the calculated third cluster number, A target code amount when re-encoding the first video signal and the second video signal is calculated, and a generated code amount obtained by re-encoding the first video signal and the second video signal is Goal mark Control the re-encoding of the first video signal and the second video signal to re-encode the first video signal and the second video signal so that the first re-encoding Generating an encoded stream and a second re-encoded stream.

  In one aspect of the present invention, information for performing re-encoding by setting a target code amount when recording the second encoded stream in a predetermined section of the first encoded stream recorded on the recording medium. In the processing, the first code from the first position before the IN point that is the start position of the predetermined section to the second position after the OUT point that is the end position of the predetermined section From the first number of clusters required for recording the encoded stream and the third position near the start position of the second encoded stream, the fourth position near the end position of the second encoded stream And the second number of clusters required for recording until the first encoded stream from the first position to the IN point is decoded and the second cluster number is used. Starting position of the encoded stream A first video signal connected to a video signal obtained by decoding the second encoded stream from the third position to the third position, and the second encoded stream from the fourth position. And a video signal obtained by decoding the second encoded stream up to the end position, and a video signal obtained by decoding the first encoded stream from the OUT point to the second position; Is calculated, and the third number of clusters that can be used for recording the second video signal connected to the second video signal is calculated, and the calculated third cluster number is used to calculate the first video signal and the second video signal. A target code amount for re-encoding the video signal is calculated, and the generated code amount obtained by re-encoding the first video signal and the second video signal becomes the target code amount. 1 movie Re-encoding of the signal and the second video signal is controlled, the first video signal and the second video signal are re-encoded, and the first re-encoded stream and the second re-encoded stream are Generated.

  According to one aspect of the present invention, an insert edited stream can be recorded on a recording medium. In particular, according to one aspect of the present invention, it is possible to reliably record an insert edited stream on a recording medium.

  Embodiments of the present invention will be described below. Correspondences between the constituent elements of the present invention and the embodiments described in the specification or the drawings are exemplified as follows. This description is intended to confirm that the embodiments supporting the present invention are described in the specification or the drawings. Therefore, even if there is an embodiment which is described in the specification or the drawings but is not described here as an embodiment corresponding to the constituent elements of the present invention, that is not the case. It does not mean that the form does not correspond to the constituent requirements. Conversely, even if an embodiment is described here as corresponding to a configuration requirement, that means that the embodiment does not correspond to a configuration requirement other than the configuration requirement. It's not something to do.

  An information processing apparatus according to an aspect of the present invention sets a target code amount and re-encodes a second encoded stream in a predetermined section of the first encoded stream recorded on a recording medium. An information processing apparatus that performs a process from a first position before an IN point that is a start position of the predetermined section to a second position after an OUT point that is an end position of the predetermined section From the first cluster number required for recording the first encoded stream and the third position in the vicinity of the start position of the second encoded stream, the end position of the second encoded stream is determined. Video obtained by decoding the first encoded stream from the first position to the IN point using the second number of clusters required for recording up to the fourth position in the vicinity Of the signal and the second encoded stream A first video signal connected to a video signal obtained by decoding the second encoded stream from a start position to the third position, and the second code from the fourth position. Video signal obtained by decoding the second encoded stream up to the end position of the encoded stream and video obtained by decoding the first encoded stream from the OUT point to the second position A cluster number calculating means for calculating a third cluster number that can be used for recording the second video signal connected to the signal (for example, the cluster calculating unit 141 in FIG. 6), the first video signal, Re-encoding means for re-encoding the second video signal to generate a first re-encoded stream and a second re-encoded stream (for example, the encoder 59 in FIG. 4), and the class Code amount calculation means for calculating a target code amount for re-encoding the first video signal and the second video signal using the third cluster number calculated by the number calculation means (for example, FIG. 6 code amount calculation unit 142) and re-encoding by the re-encoding means so that a generated code amount obtained by re-encoding the first video signal and the second video signal becomes the target code amount. Re-encoding control means (for example, the encoding control unit 128 in FIG. 6).

  The information processing apparatus includes the first re-encoded stream generated by the re-encoding unit, the second encoded stream from the third position to the fourth position, and the second re-encoded stream. Recording means (for example, in FIG. 4) that connects the encoded streams and records the first encoded stream from the first position to the second position on the recording medium at the position where the first encoded stream is recorded. A drive 47) can further be provided.

  The cluster number calculation means uses the third cluster number to use the fourth cluster number that can be used for recording the first video signal and the second video signal that is used for recording. The number of possible fifth clusters is further obtained (for example, the process of step S16 in FIG. 12), and the code amount calculation means determines that the number of fourth clusters is larger than the number of pictures in the first video signal. The target code amount of the first video signal is calculated based on a sixth cluster number obtained by subtracting a number smaller by 1 and the picture of the second video signal is calculated from the fifth cluster number. The target code amount of the second video signal can be calculated based on the seventh cluster number obtained by subtracting the number smaller by 1 than the number (for example, the process of step S52 in FIG. 15). .

  The code amount calculation means calculates the occupancy of the VBV buffer at the first position and the occupancy of the VBV buffer at the third position from a value obtained by multiplying the sixth cluster number by the cluster size. A value obtained by subtracting the difference is calculated as the target code amount of the first video signal, and the fourth position is calculated from a value obtained by multiplying the seventh cluster number by the cluster size. The value obtained by subtracting the difference between the occupancy of the VBV buffer at the second position and the occupancy of the VBV buffer at the second position is calculated as the target code amount of the second video signal (for example, step S52 in FIG. 15). Processing).

  The code amount calculation means further calculates a bit rate when the first video signal is re-encoded using the target code amount of the first video signal, and the second video signal The bit rate when the second video signal is re-encoded can be calculated using the target code amount (for example, the process of step S53 in FIG. 15).

  The information processing apparatus obtains a first remaining cluster number that is a difference between the fourth cluster number and the number of clusters required for recording the first re-encoded stream, and the first remaining cluster number The number of clusters is allocated to each GOP constituting the first re-encoded stream, dummy data corresponding to the number of clusters allocated to each GOP is inserted at the end of those GOPs, and the fifth cluster number And a second remaining cluster number that is a difference between the number of clusters required for recording the second re-encoded stream, and the second remaining cluster number is determined as the second re-encoded stream. And inserting means (for example, dummy data insertion unit 129 in FIG. 6) for inserting dummy data for the number of clusters allocated to each GOP at the end of those GOPs. it can.

  An information processing method or program according to one aspect of the present invention sets a target code amount when recording a second encoded stream in a predetermined section of a first encoded stream recorded on a recording medium. For executing information processing for performing re-encoding, from a first position before an IN point that is a start position of the predetermined section, to an OUT point that is an end position of the predetermined section From the first number of clusters required for recording the first encoded stream up to the second position after the second and the third position in the vicinity of the start position of the second encoded stream, the second The first encoded stream from the first position to the IN point using the second number of clusters required for recording up to the fourth position in the vicinity of the end position of the encoded stream of Decoded video A video signal obtained by decoding the second encoded stream from the start position of the second encoded stream to the third position, and the video signal obtained by decoding the second encoded stream, and The video signal obtained by decoding the second encoded stream from the fourth position to the end position of the second encoded stream, and the first code from the OUT point to the second position The third number of clusters that can be used for recording the second video signal connected to the video signal obtained by decoding the video stream is calculated (for example, step S15 in FIG. 12), and the calculated Using the third number of clusters, a target code amount for re-encoding the first video signal and the second video signal is calculated (for example, step S52 in FIG. 15), and the first video signal is calculated. And Re-encoding of the first video signal and the second video signal is controlled such that a generated code amount obtained by re-encoding the second video signal becomes the target code amount, Re-encoding the video signal and the second video signal to generate a first re-encoded stream and a second re-encoded stream (eg, step S54 and step S57 in FIG. 15).

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

  FIG. 4 is a block diagram showing a hardware configuration of the editing apparatus 31 to which the present invention is applied.

  A CPU (Central Processing Unit) 41 is connected to the North Bridge 42, and controls processing such as reading of data recorded on an HDD (Hard disk Drive) 46 or a recording medium 48, and editing executed by the CPU 52, for example. Generate and output control signals and commands for controlling processing. The north bridge 42 is connected to a PCI bus (Peripheral Component Interconnect / Interface) 44 and receives supply of data recorded in the HDD 46 or the recording medium 48 via the south bridge 45 based on the control of the CPU 41, for example. Then, the data is supplied to the memory 50, the decoder 54, or the decoder 55 via the PCI bus 44 and the PCI bridge 49. The north bridge 42 is also connected to the memory 43, and exchanges data necessary for the processing of the CPU 41.

  The memory 43 stores data necessary for processing executed by the CPU 41. The south bridge 45 controls writing and reading of data in the HDD 46. In the HDD 46, compressed video data (hereinafter, referred to as base data), which is a target of compression-encoded insert editing recorded on the recording medium 48, is inserted at a predetermined position. (Also referred to as overwrite data as appropriate) is recorded.

  In addition, a drive 47 is connected to the south bridge 45, and the drive 47 reads background data from the recording medium 48, and records background data and overwrite data supplied from the south bridge 45 on the recording medium 48. To do. The recording medium 48 is made of, for example, a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory, and records background data to be subjected to insert editing.

  The PCI bridge 49 controls the writing and reading of data in the memory 50, the supply of compressed video data to the decoder 54, the decoder 55, or the stream splicer 57, and the data on the PCI bus 44 and the control bus 51. Control the transfer of. The memory 50 stores, under the control of the PCI bridge 49, compressed video data that is read from the HDD 46 or the recording medium 48 and that is subjected to insert editing, and compressed video data that has been edited and supplied from the stream splicer 57. .

  The CPU 52 is connected to the PCI bridge 49, the decoder 54 to the decoder 56, the stream splicer 57, in accordance with control signals and commands supplied from the CPU 41 via the north bridge 42, the PCI bus 44, the PCI bridge 49, and the control bus 51. Processes executed by the effect / switch 58, the encoder 59, and the switch 60 are controlled. The memory 53 stores data necessary for the processing of the CPU 52.

  Based on the control of the CPU 52, the decoders 54 to 56 decode the supplied compressed video data and output an uncompressed video signal (baseband image data). The decoders 54 to 56 may be provided as independent devices that are not included in the editing device 31. For example, when the decoder 56 is provided as an independent device, the decoder 56 can receive, decode, and output compressed video data that has been edited and generated by processing to be described later. .

  Based on the control of the CPU 52, the stream splicer 57 supplies the supplied compressed video data to the decoder 56, or supplies the compressed video data to the memory 50 via the PCI bridge 49 for storage. The stream splicer 57 can also receive the data obtained in the encoding process from the encoder 59, supply the data to the memory 50 via the PCI bridge 49, and store the data.

  The effect / switch 58 switches the output of the uncompressed video signal supplied from the decoder 54 or the decoder 55 based on the control of the CPU 52. That is, the effect / switch 58 combines the supplied non-compressed video signal with a predetermined frame, applies an effect to a predetermined range as necessary, and supplies it to the encoder 59. The encoder 59 encodes the supplied uncompressed video signal based on the control of the CPU 52. That is, the encoder 59 encodes an uncompressed video signal to generate a re-encoded stream that is a re-encoded stream.

  Based on the control of the CPU 52, the switch 60 receives either the baseband image signal output from the effect / switch 58 or the baseband image signal supplied from the stream splicer 57 and decoded by the decoder 56. For example, to a display device.

  Next, the operation of the editing device 31 will be described.

  Background data (encoded stream) compressed by the Long GOP Open GOP method is recorded on the recording medium 48, and overwrite data (encoded stream) to be inserted into the background data is recorded on the HDD 46. . That is, the stream A2 shown in FIG. 2 is recorded as background data on the recording medium 48, and the stream B2 shown in FIG. The CPU 41 receives a user's operation input from an operation input unit (not shown), and receives two streams to be edited and information on the editing points.

  In the following description, the position IN2 or the position IN3 where the stream A2 and the stream B2 are connected is also referred to as an IN point. The position OUT2 or the position OUT3 where the stream A2 and the stream B2 are connected is also referred to as an OUT point.

  Based on the GOP structure of the stream A2 and the stream B2, which are compressed video data that has been compression-encoded (encoded), and the information indicating the editing point, that is, the IN point and the OUT point, the CPU 41, among the stream A2 and the stream B2, A range for re-encoding (hereinafter referred to as a re-encoding section) is determined. Then, the CPU 41 executes processing for connecting the re-encoding sections of the stream A2 and the stream B2 at the editing point to form one stream while maintaining the continuity of the VBV occupation amount of the VBV Buffer Model.

  That is, the CPU 41 is supplied with the stream necessary for executing the re-encoding process of the re-encoding section, that is, the portion from the position α2 to the position IN2 of the stream A2, to the decoder 54, and from the position IN3 to the position β2 of the stream B2. The part is supplied to the decoder 55, and is connected by the effect / switch 58 at the edit point, that is, the IN point, and the control signal is generated so that the effect is applied if necessary, and the north bridge 42, PCI bus 44, PCI The data is sent to the CPU 52 via the bridge 49 and the control bus 51.

  Similarly, the CPU 41 supplies the part from the position γ2 to the position OUT3 of the stream B2 to the decoder 55, and supplies the part from the position OUT2 to the position δ2 of the stream A2 to the decoder 54. That is, a control signal is generated so as to be connected at the OUT point and an effect is applied as necessary, and is transmitted to the CPU 52 via the north bridge 42, the PCI bus 44, the PCI bridge 49, and the control bus 51.

  In this way, the stream C2 and the stream D2 as the uncompressed video signals obtained by connecting the stream A2 and the stream B2 at the IN point and the OUT point, respectively, are obtained by the encoder 59 based on the control of the CPU 52. Re-encoding is performed to obtain compressed video data (re-encoded stream).

  When the re-encoding operation is completed, the CPU 52 stores the stream C2 and the stream D2 as the re-encoded compressed video data (re-encoded stream) from the encoder 59 through the stream splicer 57 and the PCI bridge 49. Each unit is controlled to be supplied to 50. Further, the CPU 41 determines that the stream C2 stored in the memory 50, the portion from the position β2 to the position γ2 of the stream B2 recorded in the HDD 46, and the stream D2 stored in the memory 50 are streamed in the recording medium 48. Each part is controlled so that the part from position α2 to position δ2 of A2 is overwritten on the recorded position.

  Next, FIG. 5 is a block diagram illustrating a functional configuration example of the editing device 31 in FIG. In FIG. 5, parts corresponding to those in FIG. 4 are denoted by the same reference numerals, and description thereof is omitted as appropriate.

  The editing device 31 includes a control unit 91, an acquisition unit 92, a drive 47, a decoder 54, a decoder 55, and an encoder 59.

  The control unit 91 includes a CPU 41 and a CPU 52 and controls each unit of the editing device 31. The acquisition unit 92 acquires compressed video data from the HDD 46 or the recording medium 48 via the drive 47 based on the control of the control unit 91 and supplies the compressed video data to the decoder 54 or the decoder 55. The HDD 46 in which the compressed video data is recorded may be included in the acquisition unit 92, or the acquisition unit 92 acquires the compressed video data as overwrite data from another device connected to the editing device 31. You may do it.

  The decoder 54 and the decoder 55 decode the compressed video data supplied from the acquisition unit 92 and supply the uncompressed video signal obtained as a result to the encoder 59. Note that the editing device 31 shown in FIG. 5 includes two decoders 54 and 55 as decoders for decoding the compressed video data, but the editing device 31 may have only one decoder. 3 or more.

  The encoder 59 encodes the connected video signal decoded by the decoder 54 and the decoder 55, and supplies the compressed video data obtained by the encoding to the drive 47 via the acquisition unit 92.

  Further, the control unit 91 is configured as shown in FIG. 6 in more detail.

  That is, the control unit 91 includes a CPU 41 and a CPU 52. The CPU 41 includes an operation input acquisition unit 121, a re-encode section determination unit 122, a parameter transmission unit 123, and a stream transmission control unit 124. The CPU 52 includes a stream acquisition control unit 125, a decoding control unit 126, and a parameter acquisition unit. 127, an encoding control unit 128, and a dummy data insertion unit 129.

  The operation input acquisition unit 121 receives an operation input by the user, acquires information according to a user operation such as information on a stream to be inserted and edited and edit points, and the acquired information is re-encoded section determination unit 122 or stream This is supplied to the sending control unit 124.

  The re-encode section determination unit 122 determines the re-encode section based on the information about the stream to be edited and the edit point from the operation input acquisition unit 121. The re-encoding section determination unit 122 supplies information indicating the determined re-encoding section to the parameter transmission unit 123 and the stream transmission control unit 124.

  The parameter transmission unit 123 supplies various parameters necessary for re-encoding the stream to the parameter acquisition unit 127 based on the information indicating the re-encoding interval from the re-encoding interval determining unit 122. The parameter transmission unit 123 includes a cluster number calculation unit 141. The cluster number calculation unit 141 is used when recording the portion from the position α2 to the position β2 near the IN point and the portion from the position γ2 to the position δ2 near the OUT point, which are re-encoding sections, on the recording medium 48. The number of clusters that can be calculated is calculated.

  Based on the information from the operation input acquisition unit 121 and the information indicating the re-encode section from the re-encode section determination unit 122, the stream transmission control unit 124 transmits the stream to be edited by editing to the decoder 54 or the decoder 55. Thus, the acquisition unit 92 is controlled. In addition, the stream transmission control unit 124 responds to a user operation such as editing or recording of a stream based on the information from the operation input acquisition unit 121 and the information indicating the re-encoding section from the re-encoding section determining unit 122. A control signal for performing processing is supplied to the stream acquisition control unit 125.

  The stream acquisition control unit 125 controls acquisition of a stream to be insert edited based on a control signal from the stream transmission control unit 124. In addition, the stream acquisition control unit 125 instructs the decoding control unit 126 to perform decoding control or instructs the encoding control unit 128 to perform encoding control based on the control signal from the stream transmission control unit 124. In addition, the stream acquisition control unit 125 inserts dummy data, which will be described later, into each of the stream C2 and the stream D2 temporarily stored in the memory 50 as the acquisition unit 92 based on the result of encoding in the re-encoding section. As described above, the dummy data insertion unit 129 is instructed to insert dummy data.

  Here, the dummy data is data that is added to the code that is actually generated by re-encoding so that the stream C2 and the stream D2 satisfy the number of assigned clusters, and the stream C2 or stream D2 is stream data. Data that is D2 data but is not actually used for reproduction.

  The decoding control unit 126 controls the decoding of the stream according to the instruction from the stream acquisition control unit 125. The parameter acquisition unit 127 acquires various parameters necessary for re-encoding the stream from the parameter transmission unit 123 and supplies the acquired parameters to the encoding control unit 128.

  The encoding control unit 128 controls the re-encoding of the edited stream based on the parameter from the parameter acquisition unit 127 according to the instruction of the stream acquisition control unit 125. The encoding control unit 128 includes a code amount calculation unit 142. The code amount calculation unit 142 is used for the part from the position α2 to the position β2 and the part from the position γ2 to the position δ2 that are included in the parameters from the parameter acquisition unit 127 and are the re-encoding section. Based on the number of clusters that can be generated, the amount of generated code that is the target of each of the portion from position α2 to position β2 and the portion from position γ2 to position δ2 is calculated.

  In response to an instruction from the stream acquisition control unit 125, the dummy data insertion unit 129 inserts dummy data into each of the stream C2 and the stream D2 temporarily stored in the acquisition unit 92.

  By the way, in order for the editing apparatus 31 to overwrite the portion from the position j2 to the section k2 of the stream E2 in FIG. 2 with the portion from the position α2 to the position δ2 of the stream A2, from the section j2 to the section k2 of the stream E2. The number of clusters necessary for recording the part of the recording medium 48 needs to be equal to or less than the number of clusters in which the part from position α2 to position δ2 in the stream A2 on the recording medium 48 is recorded.

  Here, as shown in FIG. 7, the number of clusters required to record the compressed video data for one frame of the stream to be re-encoded, that is, one picture, differs depending on the code amount of the frame. In the figure, the horizontal axis indicates the code amount of one frame, and the vertical axis indicates the number of clusters necessary for recording the compressed video data of that frame.

  In FIG. 7, the number of clusters necessary for recording compressed video data increases by 1 as the data amount of compressed video data, that is, the code amount of a frame increases by a certain amount. Therefore, the maximum code amount that can be recorded in the recording area of the predetermined number of clusters on the recording medium 48 increases linearly in proportion to the number of clusters.

  For example, when the code amount of a frame is greater than 0 and less than or equal to a predetermined amount, the number of clusters is 1, and when the code amount is greater than F1 and less than or equal to F2, the number of clusters necessary for recording is Five. The code amount from F1 to F2, that is, the code amount obtained by the code amount F2-F1 is the maximum data amount that can be recorded in one cluster, that is, the size of the cluster.

  The editing apparatus 31 records the code amount of the part from the section j2 to the section k2 of the stream E2 in FIG. 2 with the number of clusters equal to or less than the number of clusters in which the part from the position α2 to the position δ2 in the stream A2 is recorded. So that the stream C2 and the stream D2 are re-encoded.

  For example, when the occupancy of the VBV buffer from the position α2 to the position δ2 transitions as shown in FIG. 8 and each picture is stored and recorded in a cluster, the editing device 31 uses the number of clusters and the stream E2 The stream C2 and the stream D2 are re-encoded so that the part from the section j2 to the section k2 can be recorded.

  In FIG. 8, the horizontal axis indicates time, and the vertical axis indicates the occupancy of the VBV buffer, that is, the occupation amount. A broken line Z1 indicates a change in the occupancy of the VBV buffer. In the figure, one rectangle indicates one cluster.

  The slope of the broken line Z1 indicates the bit rate at which the stream is transmitted, that is, the code amount per unit time at which the stream is taken into the buffer in the decoding side apparatus. Further, in the figure, the amount of decrease in occupancy in the portion where the line Z1 sharply decreases in the vertical direction is the code of each frame, that is, each picture taken out from the buffer in the frame playback period for playback of each frame. In the example of FIG. 8, ten frames are extracted.

  Therefore, on the recording medium 48, these frames are stored and recorded in clusters indicated by rectangles in FIG. 8, and the total number of clusters is 52. Here, each of the clusters indicated by the arrows W1 to W8 has a cluster gap. That is, in each of the clusters indicated by the arrows W1 to W8, there is an area where the compressed video data of the frame is not recorded.

  The editing device 31 can store and record the code amount from the section j2 to the section k2 of the stream E2 in 52 clusters that can be used for recording the portion of the section. Stream C2 and stream D2 are re-encoded so that continuity is maintained and the VBV buffer does not fail, that is, neither overflow nor underflow.

  For example, stream A2 is a stream encoded by CBR, and stream C2 is re-encoded by CBR at the same bit rate as stream A2 so that the continuity of the VBV buffer is maintained and the VBV buffer does not fail In this case, it is assumed that the occupancy of the VBV buffer has changed as shown in FIG.

  In FIG. 9, the horizontal axis indicates time, and the vertical axis indicates the occupancy of the VBV buffer. A broken line indicates a change in the occupancy of the VBV buffer. Further, OC1 indicates the occupancy at the position α2 of the stream A2, and OC2 indicates the occupancy at the position β2 of the stream B2.

  In FIG. 9, since the occupancy at the start position of the stream C2 is OC1 and the occupancy at the end position of the stream C2 is OC2, as shown by the broken line, the continuity of the occupancy with the stream A2 and the stream B2 is It is kept. Further, the occupancy indicated by the broken line does not overflow or underflow.

  However, since the bit rate of the stream C2 is the same as the bit rate of the stream A2, the code amount of the stream C2 in this case is the same as the code amount of the position corresponding to the position β2 from the position α2 of the stream A2, There is a possibility that the stream C2 cannot be recorded with the number of clusters in which the stream A2 is recorded. In this case, it is assumed that the bit rate of the stream B2 is the same as the bit rate of the stream A2.

  Therefore, as shown in FIG. 10, the editing apparatus 31 sets the difference Δ between the occupancy OC1 at the start position of the stream C2 and the occupancy OC2 at the end position, and the number of clusters that can be used for recording the stream C2 and the stream D2. Based on this, the target code amount of the stream C2 at the time of re-encoding is changed.

  In FIG. 10, the broken line indicated by the dotted line corresponds to the broken line in FIG. 9, and the broken line indicated by the solid line in FIG. 10 represents the temporal change in the occupancy of the stream C2 whose code amount has been changed. Show.

  In FIG. 10, the code amount of the compressed video data of each frame in the solid line is smaller than the code amount in the dotted line before the change. Further, since the code amount of the stream C2 is changed, the bit rate is changed accordingly, and the inclination of the occupancy indicated by the solid line is gentler than the inclination of the occupancy before the change indicated by the dotted line. That is, in FIG. 10, the bit rate of the occupancy indicated by the solid line is lower than the bit rate of the occupancy of the broken line before the change indicated by the dotted line.

  Similarly, the editing apparatus 31 also performs re-encoding of the stream D2 so that the code amount of the stream D2 decreases. As described above, when the re-encoding of the stream C2 and the stream D2 is performed so that the code amounts of the stream C2 and the stream D2 are reduced as necessary, the portion from the section j2 to the section k2 is changed from the position α2 of the stream A2. Recording can be performed by overwriting the portion at position δ2. Further, since the code amounts of the stream C2 and the stream D2 are also reduced, underflow does not occur and the VBV buffer does not fail.

  In addition, when there is a sufficient number of clusters for recording the stream C2 and the stream D2, and it is not necessary to reduce the code amount of the stream C2 and the stream D2, the target code of the stream C2 and the stream D2 at the time of re-encoding The amount may be a code amount as it is or may be increased.

  Further, it is assumed that the stream C2 re-encoded so that the code amount is reduced in this way is encoded by VBR (Variable Bit Rate) instead of CBR, and the bit rate when the code amount is not changed, that is, The occupancy of the VBV buffer when the stream C2 is taken into the buffer of the decoding side device at the same bit rate as the stream A2 transitions as shown in FIG.

  In FIG. 11, the broken line indicated by the dotted line corresponds to the broken line indicated by the dotted line in FIG. 10, and the broken line indicated by the solid line in FIG. 11 indicates the occupancy time of the stream C2 in which the code amount is changed. Changes.

  In FIG. 11, the end position of the occupancy indicated by the solid line is larger than the occupancy OC2, and the occupancy of the stream C2 indicated by the solid line is not continuous with the occupancy of the subsequent stream B2. . However, in this case, since the stream C2 is reproduced as encoded by VBR, when the occupancy is maximized, that is, when the compressed video data of the stream C2 can no longer be stored in the VBV buffer, Since the import of the compressed video data into the VBV buffer is temporarily stopped, the VBV buffer does not overflow.

  The solid broken line indicates the change in the occupancy of the stream C2 re-encoded so that the code amount is reduced, and the code amount is reduced as compared with the dotted line. Therefore, since the dotted broken line does not underflow, the underflow does not occur even in the occupancy indicated by the solid broken line.

  In this way, by changing the code amounts of the re-encoded stream C2 and stream D2, the continuity of occupancy is maintained without breaking the VBV buffer, and from the position α2 to the position δ2 of the stream A2, which is the background data Can be overwritten with the stream C2, which is the overwrite data, the part from the position β2 to the position γ2 of the stream B2, and the stream D2.

  Next, the processing of the CPU 41 will be described with reference to the flowchart of FIG. This process is started when the user operates an operation input unit (not shown) to instruct insert editing using the compressed video data recorded on the recording medium 48 as background data.

  In step S11, the operation input acquisition unit 121 performs a GOP structure of stream A2, which is compression-coded base data, and stream B2, which is overwrite data, and editing in accordance with a user operation from an operation input unit (not shown). The information indicating the points, that is, the IN point and the OUT point is input, and the input information is supplied to the re-encoding section determining unit 122.

  In step S12, the re-encode section determination unit 122 determines the re-encode section based on the GOP structures of the stream A2 and the stream B2 supplied from the operation input acquisition unit 121 and the information indicating the edit point. When the re-encoding section determination unit 122 determines the re-encoding section, the re-encoding section determination unit 122 supplies information indicating the re-encoding section to the parameter transmission unit 123 and the stream transmission control unit 124.

  For example, the re-encoding section determination unit 122 calculates a section including a portion from the position α2 to the position IN2 near the IN point in the stream A2 and a portion from the position IN3 to the position β2 near the stream B2 near the IN point. As a re-encoding section, a section including a portion from the position γ2 to the position OUT3 in the vicinity of the OUT point in the stream B2 and a portion from the position OUT2 to the position δ2 in the vicinity of the stream A2 is set as a re-encoding section in the vicinity of the OUT point. .

  Note that the re-encoding interval near the IN point and the re-encoding interval near the OUT point shown in FIG. 2, that is, the stream C2 and the stream D2, are each 1 GOP, but are divided into a plurality of GOPs. Also good. In addition, the start position and end position of the GOP including the IN point or OUT point are the start position and end position of the re-encoding section, respectively, but before or after a predetermined number of GOPs including the IN point or OUT point. The start position or end position of the GOP may be the start position or end position of the re-encoding section.

  Furthermore, the end position of the re-encoding interval near the IN point and the re-encoding interval near the OUT point may not be a GOP break, for example, up to the picture immediately before the first I picture in the GOP, that is, the I picture A re-encoding section may be set up to the B picture arranged immediately before the.

  In step S13, the cluster number calculation unit 141 obtains the cluster number X from the start position of the re-encode section including the IN point in the background data to the end position of the re-encode section including the OUT point.

  For example, the cluster number calculation unit 141 refers to the stream A2 as background data recorded on the recording medium 48 as necessary, and based on the information indicating the re-encoding interval from the re-encoding interval determining unit 122, 13, in the stream A2 as background data, a section from the re-encoding section start position α2 including the IN point to the re-encoding section end position δ2 including the OUT point, that is, the section b2 to the section e2 The number of clusters X in the interval up to is obtained. In other words, the cluster number calculation unit 141 calculates the number of clusters in the area where the overwrite data is inserted, including the section of the stream A2 to be re-encoded on the recording medium 48.

  In step S14, the cluster number calculation unit 141 calculates the number of clusters Y from the end position of the re-encode section including the IN point in the overwrite data to the start position of the re-encode section including the OUT point.

  For example, the cluster number calculation unit 141 refers to the stream B2 as the overwrite data recorded in the HDD 46 as necessary, and based on the information indicating the re-encoding interval from the re-encoding interval determining unit 122, the cluster number calculation unit 141 in FIG. As shown, in the stream B2 as the overwriting data, from the end position β2 of the re-encoding section including the IN point to the start position γ2 of the re-encoding section including the OUT point, that is, from the section g2 to the section i2 The number of clusters Y in the section is obtained.

  Here, the size of the cluster when obtaining the number of clusters Y, that is, the cluster size, is the cluster size set for the stream A2 as the base data recorded on the recording medium 48.

  In step S15, the cluster number calculation unit 141 obtains the number of clusters that can be used for the re-encoding section including the IN point and the re-encoding section including the OUT point.

  For example, as shown in FIG. 14, since the number of clusters X from position α2 to position δ2 of stream A2 and the number of clusters Y from position β2 to position γ2 of stream B2 are already determined, re-encoding including the IN point is performed. The number of clusters that can be used in the section j2 that is the section and the section k2 that is the re-encoding section including the OUT point is the number obtained by subtracting the cluster number Y from the cluster number X, that is, XY. Therefore, the cluster number calculation unit 141 calculates the number of usable clusters for the re-encoding section including the IN point and the re-encoding section including the OUT point by calculating XY.

  In step S16, the cluster number calculation unit 141 assigns the number of usable clusters to each of the re-encoding section including the IN point and the re-encoding section including the OUT point.

  For example, the cluster number calculation unit 141 assigns the cluster number XY obtained in the process of step S15 to the re-encode section including the IN point by dividing the number of clusters by the ratio of the number of frames included in each re-encode section. The number of clusters CLI and the number of clusters CLO assigned to the re-encoding section including the OUT point are calculated and assigned.

  For example, when the number of clusters XY is 50 and the number of frames included in each re-encoding section is 15, the number of frames in the re-encoding section including the IN point and the frame of the re-encoding section including the OUT point Since the number is the same, the cluster number calculation unit 141 equally divides the cluster number 50 and sets the cluster number CLI and the cluster number CLO to 25 each.

  Further, the number of clusters assigned to each of the re-encoding section including the IN point and the re-encoding section including the OUT point may be obtained by a two-pass method or the like. In this case, for example, the stream of the re-encoding section including the IN point and the re-encoding section including the OUT point is encoded once in the encoder 59, and the number of clusters necessary for recording the codes generated as a result of the encoding. Based on this ratio, the cluster number calculation unit 141 apportions the cluster number XY to obtain the cluster number CLI and the cluster number CLO.

  In step S17, the parameter sending unit 123 refers to the background data recorded on the recording medium 48 and the overwrite data recorded on the HDD 46, or acquires a signal from an operation input unit (not shown). The parameters necessary for executing the re-encoding process of the re-encoding section are acquired.

  Here, the parameters necessary for executing the re-encoding process in the re-encoding section include information indicating the position, such as the number of GOPs up to the GOP including the IN point in the stream A2, and the IN point in the stream A2. Information indicating the position IN2 of the IN point in the GOP, the number of GOPs up to the next GOP of the GOP including the OUT point in the stream A2, etc., and the position OUT2 of the OUT point in the GOP including the OUT point in the stream A2 Information indicating the position, such as the number of GOPs up to the next GOP of the GOP including the IN point in the stream B2, information indicating the position IN3 of the IN point in the GOP including the IN point in the stream B2, and the OUT point in the stream B2 The information indicating the position, such as the number of GOPs up to the GOP that includes, and the OUT point position OUT3 in the GOP that includes the OUT point in the stream B2 Information, the first VBV value of the frame of the beginning of the VBV value and the next GOP of the re-encoding section (i.e., VBV target value in the re-encoding section), and the like information indicating whether or types of effects of effect.

  In addition, other parameters necessary for executing the re-encoding process are the size of the cluster, the number of clusters CLI allocated to the re-encoding section including the IN point, and the re-encoding section including the OUT point. The number of clusters, CLO, etc. are also included. Further, the parameter transmission unit 123 supplies the stream transmission control unit 124 with information indicating the presence or absence of the acquired effect or the effect type.

  In step S18, the stream transmission control unit 124, based on the information indicating the re-encoding period from the re-encoding period determining unit 122, the decoder 54 and the decoder 55 of the stream necessary for executing the re-encoding process of the re-encoding period. Controls sending to

  Specifically, the stream transmission control unit 124, from the position α2 to the position IN2 of the stream A2 as the base data recorded on the recording medium 48, that is, the stream necessary for executing the re-encoding process of the re-encoding section. And the portion from the position OUT2 to the position δ2 of the stream A2 (including a frame necessary for decoding the portion after the position OUT2 before the position OUT2) is supplied to the decoder 54, and the HDD 46 A portion from position IN3 to position β2 of stream B2 as overwrite data recorded in (including a frame necessary for decoding a portion after position IN3 before position IN3), and a stream A portion of B2 from position γ2 to position OUT3 is supplied to the decoder 55. Sea urchin and controls each unit.

  Based on the control of the stream transmission control unit 124, the drive 47 reads the part from the position α2 to the position IN2 and the part from the position OUT2 to the position δ2 of the stream A2 from the recording medium 48, the south bridge 45, the north bridge 42, the PCI bus 44, and the PCI bridge 49 are supplied to the decoder 54.

  Further, the south bridge 45 acquires the part from the position IN3 to the position β2 and the part from the position γ2 to the position OUT3 of the stream B2 from the HDD 46 based on the control of the stream transmission control unit 124, and the north bridge 42, The data is supplied to the decoder 55 via the PCI bus 44 and the PCI bridge 49.

  Further, the stream transmission control unit 124 decodes the portion from the position α2 to the position IN2 of the stream A2 and the portion from the position IN3 to the position β2 of the stream B2 in the decoder 54 and the decoder 55, respectively. Are connected at the IN point, effects are applied as necessary, and control signals for controlling each part are generated so as to be re-encoded by the encoder 59, and the north bridge 42, PCI bus 44, PCI bridge 49 are generated. And to the CPU 52 via the control bus 51.

  Similarly, the stream transmission control unit 124 decodes the portion from the position OUT2 to the position δ2 of the stream A2 and the portion from the position γ2 to the position OUT3 of the stream B2 in the decoder 54 and the decoder 55, respectively. 58 is connected at the OUT point, effects are applied as necessary, and control signals for controlling each part are generated so as to be re-encoded in the encoder 59, the north bridge 42, the PCI bus 44, the PCI bridge 49 and the CPU 52 via the control bus 51.

  In step S <b> 19, the parameter sending unit 123 sends parameters necessary for executing re-encoding processing in the re-encoding section to the CPU 52 via the north bridge 42, the PCI bus 44, the PCI bridge 49, and the control bus 51. To do.

  In this way, when the re-encoded portions of the stream A2 and the stream B2 are supplied to the encoder 59 and re-encoded, the stream C2 and the stream D2 obtained by the re-encoding are sent from the encoder 59 to the stream splicer 57. And supplied to the memory 50 via the PCI bridge 49.

  Further, the dummy data insertion unit 129 of the CPU 52 inserts dummy data into the stream C <b> 2 that is temporarily stored in the memory 50. That is, the dummy data insertion unit 129 sets the stream so that the code amount of the stream C2 becomes the maximum code amount that can be recorded in the re-encoding section including the IN point, that is, the number of clusters CLI allocated to the stream C2. Insert dummy data into C2. Further, the dummy data insertion unit 129 similarly inserts dummy data into the stream D2 temporarily stored in the memory 50.

  Thus, when dummy data is inserted into the stream C2 and the stream D2, the number of clusters necessary for recording each of the stream C2 and the stream D2 into which the dummy data is inserted is the number of clusters assigned to each stream. CLI and cluster number CLO.

  When the stream C2 and the stream D2 are stored in the memory 50, the stream acquisition control unit 125 of the CPU 52 generates a signal indicating that the re-encoding is completed, and the signal is transmitted to the control bus 51, the PCI bridge 49, the PCI bus 44, The data is supplied to the stream transmission control unit 124 of the CPU 41 via the north bridge 42.

  When a signal indicating that re-encoding has been completed is supplied from the stream acquisition control unit 125 to the stream transmission control unit 124, in step S20, the stream transmission control unit 124 selects a stream that is compressed video data obtained by re-encoding. Controls transfer of C2 and stream D2 to memory 43.

  That is, the stream transmission control unit 124 causes the PCI bridge 49 to acquire the stream C2 and the stream D2 stored in the memory 50, and supply the stream 43 to the memory 43 via the PCI bus 44 and the north bridge 42.

  In step S <b> 21, the stream transmission control unit 124 controls transfer of the stream B <b> 2 as overwrite data that does not include the re-encode section to the memory 43. In other words, the stream transmission control unit 124 determines the portion from the section g2 to the section i2 that is not included in the re-encoding section among the sections from the position IN3 to the position OUT3 of the stream B2 inserted as the overwrite data in the stream A2. 45 is acquired from the HDD 46 and supplied to the memory 43 via the north bridge 42.

  In step S22, the stream transmission control unit 124 inserts the stream inserted into the stream A2 stored in the memory 43, that is, the stream C2, the portion from the section g2 to the section i2 of the stream B2, and the recording medium 48 of the stream D2. The recording is controlled, and the process ends.

  More specifically, the stream transmission control unit 124 connects the stream C2 stored in the memory 43 to the north bridge 42 and the portion from the section g2 to the section i2 of the stream B2, and further, the stream B2 The stream from the section g2 to the section i2 is connected to the stream D2. Then, the stream transmission control unit 124 causes the north bridge 42 to acquire the connected stream C2, the portion from the section g2 to the section i2 of the stream B2, and the stream D2, which are stored in the memory 43, and the south It is supplied to the drive 47 through the bridge 45. Also, the drive 47 controls the stream C2 supplied from the north bridge 42, the portion from the section g2 to the section i2 of the stream B2, and the stream D2 under the control of the stream transmission control unit 124, and the stream A2 in the recording medium 48. The portion from position α2 to position δ2 is overwritten.

  Thereby, the part from the position α2 to the position δ2 of the stream A2 recorded on the recording medium 48 is rewritten into a stream consisting of the stream C2, the part from the section g2 to the section i2 of the stream B2, and the stream D2. The stream E2 is set, and the insert editing ends.

  Here, each of the stream C2 and the stream D2 is re-encoded so as to have the assigned cluster number CLI and the cluster number CLO, and dummy data is inserted as necessary. The number of clusters necessary for recording the stream from section g2 to section i2 and stream D2 is the same as the number of clusters from position α2 to position δ2 of stream A2, and the number of clusters is different. This prevents the recorded stream from being recorded.

  In this way, the CPU 41 obtains the number of clusters that can be used for the re-encoding section, and instructs the CPU 52 to re-encode the re-encoding section so that the stream of the re-encoding section can be recorded with the obtained number of clusters. To do. Then, the CPU 41 controls the recording so that the re-encoded stream and the portion not including the re-encoding section of the stream B2 as the overwrite data are inserted into the background data in the recording medium 48.

  In this way, the number of clusters that can be used in the re-encoding section is obtained, and the re-encoding section is re-encoded so that the stream of the re-encoding section can be recorded with the obtained number of clusters. Overwrite data can be surely recorded in a portion to be replaced with data. Therefore, even when the remaining recording capacity that can be recorded on the recording medium 48 is small, insert editing can be performed.

  In this way, when a control signal for controlling the re-encoding of the stream is sent from the CPU 41 to the CPU 52, the CPU 52 starts a process for controlling the re-encoding of the stream in accordance with the control signal.

  Hereinafter, the processing of the CPU 52 will be described with reference to the flowchart of FIG.

  In step S51, the parameter acquisition unit 127 acquires parameters necessary for executing the re-encoding processing of the re-encoding section, which is transmitted by the parameter transmission unit 123 of the CPU 41 in step S19 of FIG. This is supplied to the encoding control unit 128.

  In step S <b> 52, the code amount calculation unit 142 of the encoding control unit 128 calculates a code amount that can be used for the re-encoding section based on the parameter from the parameter acquisition unit 127.

  For example, the code amount calculation unit 142 includes the number of pictures Ni in the re-encoding section including the IN point and the number of clusters assigned to the re-encoding section CLI included in the parameters necessary for executing the re-encoding process. , The size CS of the cluster, and the VBV value at the beginning of the re-encoding interval including the IN point and the VBV value of the first frame of the next GOP, the code that can be used for the re-encoding interval including the IN point Calculate the amount.

  When the size CS of the cluster, that is, the cluster size CS is NiByte or more and the re-encoding section including the IN point is 1 GOP, when Ni pictures are variable-length encoded, the result is obtained as a result. Of the clusters necessary for recording the code, the range of the number of clusters having a cluster gap (hereinafter referred to as half-end clusters as appropriate) is 0 to Ni.

  That is, when a half-end cluster occurs in the recording of any picture, the number of half-end clusters at the time of recording the re-encoded stream C2 is the maximum, and the number is Ni. If no half-end cluster occurs in the recording of any picture, the number of half-end clusters at the time of recording the re-encoded stream C2 is minimized, and the number is zero.

  Here, when the number of half-end clusters is minimized, that is, when the code amount of the stream C2 is an integer multiple of the cluster size CS, the code amount of each picture is changed without changing the entire code amount of the stream C2. The code amount of (Ni-1) pictures is changed so that, for example, 1 byte of data is recorded in each half-end cluster so that half-end clusters are generated when (Ni-1) pictures are recorded. When the code amount is increased, the code amount of the remaining one picture is decreased by the increase in the code amount of (Ni-1) pictures.

  Therefore, when the code amount of the stream C2 is an integral multiple of the cluster size CS and the code amount of each picture is changed so that the overall code amount does not change, The difference in the number of clusters necessary for recording the stream C2 from the time when the number of half-end clusters is minimum, that is, the number of clusters necessary for recording the stream C2 when there are no half-end clusters is Xm It can be represented by (1).

  (Cluster number difference) = (Xm + (Ni-1))-Xm (1)

  Here, since the right side of Expression (1) cancels Xm and -Xm and becomes (Ni-1), when the code amount of the stream C2 is an integral multiple of the cluster size CS, the total code amount thereof The difference between the maximum number and the minimum number of clusters required for recording the stream C2 when the code amount of each picture is changed is (Ni-1).

  Similarly, when the number of half-end clusters at the time of recording of the stream C2 is the maximum, that is, when half-end clusters occur in the recording of each picture, the code amount of each picture is changed without changing the entire code amount of the stream C2. When the code amount of (Ni-1) pictures is reduced so that a half-end cluster does not occur when recording (Ni-1) pictures, the code amount of the remaining one picture is It increases by a decrease in the code amount of (Ni-1) pictures. In such a case, the number of clusters required for recording the remaining one picture in which a half-end cluster is generated increases by (Ni-1) when the number of clusters increases the most, and 1 when the number of clusters does not increase the most. The number does not increase.

  Here, when the number of clusters increases the most, it is a case where a half-end cluster in which (CS-1) Byte data is recorded exists in all pictures. When it does not increase the most, only 1 Byte exists in all pictures. This is a case where there is a half-end cluster in which no data is recorded.

  Therefore, a half-end cluster is generated in the recording of each picture of the stream C2, and when the code amount of each picture is changed so that the entire code amount does not change, the number of half-end clusters is minimized. The difference in the number of clusters necessary for recording the stream C2 from the maximum is the number of clusters necessary for recording the stream C2 when the number of odd-numbered clusters is the maximum, that is, before the picture code amount is changed. Can be expressed by the following equation (2).

  (Cluster number difference) = Xm− (Xm− (Ni−1)) (2)

  Here, since the right side of Equation (2) becomes (Ni-1) by canceling Xm and -Xm, when a half-end cluster occurs in recording of each picture, the entire code amount does not change. When the code amount of each picture is changed, the difference between the maximum number and the minimum number of clusters necessary for recording the stream C2 is (Ni-1).

  Therefore, when the stream code in the re-encoding section with Ni pictures is cluster-managed for each picture and recorded on the recording medium 48, the code quantity of each picture is arbitrarily changed so that the stream code quantity does not change. In this case, the maximum difference between the maximum number and the minimum number of clusters necessary for stream recording is (Ni-1).

  Therefore, in the re-encoding of the stream C2, the code amount that can be recorded in the number of clusters obtained by subtracting the cluster number difference (Ni-1) from the cluster number CLI assigned to the stream C2 is the target code amount of the stream C2. By doing so, it is possible to prevent the number of clusters from becoming insufficient when recording the re-encoded stream C2. In other words, if (Ni-1) clusters are left in advance as a cluster for adjusting the shortage of the number of clusters caused by the cluster gap in the recording of the stream C2, the number of clusters at the time of recording the stream C2 There is no shortage, and the stream C2 can always be recorded in the cluster with the number of clusters CLI.

  Also, when the stream C2 is re-encoded, the stream C2 must be re-encoded so that the occupancy of the VBV buffer is continuous. For example, when the stream C2 is encoded at the same bit rate as that of the stream A2, the occupancy at the start of encoding the stream C2 and the occupancy at the end of the stream C2 are the same. When the difference between the occupancy OCE of the first frame of the next GOP of the stream C2 and the occupancy OCS of the start of the stream C2, that is, the value of OCE-OCS is Δ, the occupancy continuity during the re-encoding of the stream C2 Therefore, the code amount of the stream C2 needs to be reduced by Δ so that the occupancy at the end of the re-encoding period is larger than the occupancy OCS by the occupancy difference Δ.

  For example, in order to make the transition of the occupancy of the stream C2 become the locus shown by the solid line in FIG. 10, the code amount of the stream C2 is decreased by the value of OC2-OC1, that is, the difference occupancy Δ, that is, It is necessary to encode with the bit rate lowered by the amount of decrease in the code amount.

  Therefore, the generated code amount G targeted at the time of re-encoding of the stream C2 can be obtained by Expression (3) using the cluster number CLI assigned to the stream C2 and the occupancy difference Δ.

  G = CS (CLI− (Ni−1)) − Δ (3)

  The code amount calculation unit 142 calculates the amount of code that can be used for the stream C2, which is the re-encoding section, by calculating Expression (3) using parameters necessary for executing the re-encoding process.

  Although the case where the stream C2 is configured by 1 GOP has been described above, the same applies to the case where the stream C2 is configured by a plurality of GOPs. For example, if stream C2 is composed of n GOPs and the number of pictures constituting stream C2 is Ni, stream C2 is encoded by CBR so that the occupancy continuity of the VBV buffer is maintained. Even in this case, if (Ni-1) clusters are left as clusters for adjusting the shortage of the number of clusters caused by the cluster gap, the number of clusters will not be short when the stream C2 is recorded.

  Here, assuming that the number of pictures constituting each of the n GOPs is N1 to Nn, the number of pictures Ni constituting the stream C2 can be expressed by Expression (4).

  Ni = ΣNk (4)

  In equation (4), ΣNk represents that the sum is obtained by changing k of Nk from 1 to n. Even when the stream C2 is composed of n GOPs, the number of clusters obtained by subtracting N1 + N2 +... + Nn-1 (= Ni-1) clusters from the number of clusters CLI assigned to the stream C2. The code amount is allocated to each GOP of the stream C2 so that the re-encoded stream C2 can be recorded.

  In addition, when the cluster size CS is smaller than NiByte, the cluster gap in each half-end cluster is smaller than when the cluster size CS is NiByte or larger. The number of clusters required is less than (Ni-1). Therefore, even when the cluster size CS is smaller than NiByte, if (Ni-1) clusters are left as the clusters for adjusting the shortage of the number of clusters caused by the cluster gap in the recording of the stream C2. In addition, it is possible to prevent the number of clusters from becoming insufficient when recording the stream C2.

  Note that the number of clusters remaining in advance for adjusting the shortage of the number of clusters caused by the cluster gap may be larger than (Ni-1).

  In this way, the code amount calculation unit 142 calculates a code amount that can be used for the stream C2 in the re-encoding section. Similarly, the code amount calculation unit 142 also calculates a code amount that can be used for the stream D2 in the re-encoding section.

  When the code amount that can be used for the re-encoding section is calculated, in step S53, the code amount calculation unit 142 calculates a bit rate for encoding the re-encoding section.

  For example, when obtaining a target code amount of a predetermined GOP to be encoded in the TM (Test Model) 5 method, assuming that the number of pictures constituting the GOP is M, the target code amount G is given by (5).

  G = M × (bit rate) / (picture rate) (5)

  Here, the picture rate in Equation (5) is the number of pictures per second in the encoding section, that is, the GOP. For example, when calculating the bit rate of the stream C2, the code amount calculation unit 142 sets the number of pictures M in Equation (5) to the number of pictures Ni of the stream C2 and the code amount G to a value obtained from Equation (3). Then, a bit rate satisfying Expression (5) is obtained, and the obtained bit rate is set as a bit rate when the stream C2 is re-encoded. Note that the picture rate may be included in parameters necessary for executing the re-encoding process, or may be calculated by the code amount calculation unit 142.

  When the code amount calculation unit 142 obtains the bit rate of the stream C2, it similarly obtains the bit rate of the stream D2.

  In step S54, the encoding control unit 128 controls the decoding and encoding of the re-encoding section including the IN point, and the connection of the IN point. That is, the stream acquisition control unit 125 transmits the stream A2 from the position α2 to the position IN2 based on the control signal sent from the CPU 41 via the north bridge 42, the PCI bus 44, the PCI bridge 49, and the control bus 51. A portion of the compressed video data is decoded by the decoder 54, a portion of the compressed video data from position IN3 to position β2 of the stream B2 is decoded by the decoder 55, and each video signal obtained by the decoding is decoded by the effect / switch 58. The operation of the effect / switch 58 is controlled so as to be encoded by the encoder 59 after being connected at the IN point and an effect is applied as necessary. The decoder 54 and the decoder 55 are also controlled with respect to the decoding control unit 126. Decoding control And the encoding control unit 128 is instructed to control the encoding of the video signal in the encoder 59.

  Also, the decoding control unit 126 controls the decoding of the compressed video data in the decoder 54 and the decoder 55 in accordance with an instruction from the stream acquisition control unit 125, and the encoding control unit 128 includes the code amount calculation unit 142 for the stream C2. The encoding of the video signal in the encoder 59 is controlled so as to be encoded at the bit rate obtained by the above.

  Further, at this time, the encoding control unit 128 inserts a sequence header at the head of each GOP constituting the stream C2 in accordance with the setting of the apparatus for reproducing the insert edited stream, and adds the stream C2 to the sequence header. The encoder 59 is controlled so that the value of VBV Delay at the time of encoding or the value 0xFFFF of VBV Delay for reproducing the stream C2 as VBR is inserted.

  For example, when the value of VBV Delay when stream C2 is encoded in the sequence header is inserted, the value of VBV Delay is also inserted in advance in the sequence header of stream A2 as background data and stream B2 as overwrite data. In the device that reproduces the stream E2 that has been subjected to the insert editing, the stream E2 is assumed to be a stream encoded by CBR, and the bit rate is obtained from the value of the VBV Delay inserted in the sequence header. As indicated by the solid line in FIG. 10, the stream is taken into the buffer at the determined bit rate.

  Each section of the stream E2 is a stream encoded by CBR. However, since the bit rate of each section is different, the stream E2 is a stream encoded by VBR when considered as the entire stream E2.

  In addition, when 0xFFFF is inserted as the value of VBV Delay, in the device that reproduces the stream E2 that has been subjected to insert editing, the stream E2 is assumed to be a stream encoded by VBR and is inserted into the sequence header. The maximum value of the read bit rate is read out, and the stream is taken into the buffer at the read bit rate, as indicated by the solid line in FIG.

  When the end position of the re-encoding section is not a GOP break but a B picture arranged immediately before the first I picture in the display order in the GOP, the encoding control unit 128 determines the last position of the stream C2. Encoding is performed at the bit rate obtained by the code amount calculation unit 142 until the GOP end position, and encoding is performed at the same bit rate as the stream A2 until the subsequent B picture, that is, the end position of the re-encoding section. The encoder 59 is controlled.

  When each of the stream acquisition control unit 125, the decoding control unit 126, and the encoding control unit 128 controls the respective units, the part from the position α2 to the position IN2 of the stream A2 supplied to the decoder 54 and the decoder 55, and the stream B2 The portions from the position IN3 to the position β2 are decoded by the decoder 54 and the decoder 55, respectively, and supplied to the effect / switch 58. Then, the stream A2 and the stream B2 to be re-encoded are connected to the IN point, that is, the position IN2 and the position IN3 by the effect / switch 58 to become the stream C2, and are supplied to the encoder 59. Further, the stream C2 supplied to the encoder 59 is re-encoded by the encoder 59, supplied to the memory 50 via the stream splicer 57 and the PCI bridge 49, and stored.

  In step S55, the dummy data insertion unit 129 selects, for each GOP included in the re-encoding section including the IN point, the remaining cluster among the clusters of the CLI number allocated to the re-encoding section. To distribute.

  For example, it is assumed that the number of clusters necessary for recording the actually generated code as a result of re-encoding the stream C2, which is a stream in the re-encoding section, is CL1. In such a case, only the number of clusters obtained by subtracting the cluster number CL1 from the cluster number CLI assigned to the stream C2 remains.

  Therefore, the dummy data insertion unit 129 allocates the remaining cluster to each GOP constituting the re-encoding section so that it can be used as a cluster for recording overwrite data when insert editing is performed next time. To do.

  For example, as shown in FIG. 16A, when the re-encoding section is 1 GOP, all remaining clusters are allocated to the GOP. In FIG. 16, the vertical lines in the drawing indicate the breaks of clusters in which the pictures constituting the stream are recorded. In addition, the pictures are decoded sequentially from the left picture in the figure.

  In FIG. 16A, the stream C2 is composed of one GOP, and the remaining clusters are allocated to the GOP. The clusters allocated to the GOP are arranged at the position indicated by the arrow H1, that is, the last position of the GOP, and dummy data is recorded in these clusters. Even when the stream C2 includes a plurality of GOPs, the remaining clusters may be arranged at the last position in the last GOP constituting the stream C2.

  Further, when the stream C2 is composed of a plurality of GOPs and there is a storage capacity sufficient to store the re-encoded stream C2 in the memory 50, the remaining cluster when the stream C2 is re-encoded is the stream C2. May be prorated according to the ratio of the number of pictures in each GOP.

  For example, as shown in FIG. 16B, when the stream C2 is composed of two GOPA1 and GOPB1, the remaining clusters are prorated according to the ratio of the number of GOPA1 pictures and the number of GOPB1 pictures. Placed at the end.

  In the example of FIG. 16B, GOPA1 is composed of 10 pictures, and GOPB1 is composed of 15 pictures. In this case, 24 (= 10 + 15-1) clusters at the time of re-encoding of the stream C2 are clusters for adjusting the shortage of the number of clusters caused by the cluster gap. As a result of actually re-encoding the stream C2, 19 clusters are used for recording the stream C2 out of 24 clusters for adjusting the shortage of the number of clusters, and finally allocated to the stream C2. It is assumed that 5 clusters remain for the obtained number of clusters CLI.

  At this time, the remaining five clusters are prorated according to the ratio of the number of pictures of GOPA1 and GOPB1, that is, a ratio of 10 to 15, and two clusters are allocated to GOPA1 and three clusters are allocated to GOPB1. The The two clusters allocated to GOPA1 are arranged at a position after GOPA1 indicated by an arrow H2, and dummy data is recorded in these clusters. Similarly, three clusters allocated to GOPB1 are arranged at a position after GOPB1 indicated by an arrow H3, and dummy data is recorded in these clusters.

  When the number of clusters allocated to each GOP is not an integer as a result of apportionment based on the ratio of the number of pictures, that is, when the number of decimals becomes a decimal number, clusters are allocated one by one in descending order of the number after the decimal point.

  For example, if the number of remaining clusters is 4, when the four clusters are divided by the ratio of the number of pictures, the number of clusters allocated to GOPA1 is 1.6 (= 4 × 10 / (10 + 15)). The number of clusters allocated to GOPB1 is 2.4 (= 4 × 15 / (10 + 15)). In this case, for example, among the number of clusters of GOPA1 and GOPB1, the number after the decimal point is larger than the number of clusters of GOPA1, so the number less than the decimal of the number of clusters allocated to GOPA1 is rounded up to 2, A number less than the decimal of the number of clusters allocated to GOPB1 is rounded down to 2 to allocate 2 clusters each.

  In this way, dummy data is recorded in the cluster arranged at the end of GOPA1 and GOPB1, and is used when insert editing is performed for the GOP after the next time. That is, when GOPA1 data is recorded on the recording medium 48, the dummy data recorded at the position indicated by the arrow H2 is not used for reproduction of the stream C2, but the cluster remaining at the position indicated by the arrow H2 Therefore, when another stream is overwritten in the GOPA1 part by insert editing, the code amount of the stream to be overwritten can be increased by the dummy data cluster arranged last.

  For example, if the number of remaining clusters is 5, and all 5 clusters are allocated to GOPB1, when overwriting data is recorded in the portion where GOPB1 is recorded in the next insert editing, Overwrite data larger than the allocated five clusters can be recorded, but conversely, when overwriting data is recorded in the part where GOPA1 is recorded, the remaining five clusters in the current insert editing are recorded. Cannot be used effectively.

  Therefore, by distributing the remaining clusters to the GOPA1 and GOPB1 that make up the re-encoding section, the remaining clusters can be used effectively regardless of which GOP is subject to insert editing from the next time. .

  When the stream C2 is composed of a plurality of GOPs and the cluster cannot be apportioned and distributed to each GOP constituting the stream C2, for example, as shown in FIG. It may be arranged at the end of GOPB1, that is, at the position indicated by the arrow H4.

  Furthermore, if the stream C2 is composed of a plurality of GOPs and the memory 50 does not have enough storage capacity to store the re-encoded stream C2, the re-encoded stream C2 cannot be stored in the memory 50 any more. When this happens, the portion of the stream C2 already stored in the memory 50 is recorded on the recording medium 48.

  In such a case, when there is a part of the stream C2 that has not been re-encoded and the number of remaining pictures of the part that has not been re-encoded is Nr, the number of clusters for the part of the stream C2 that is to be re-encoded Since the number of clusters necessary for adjusting the shortage of (Nr-1) is at most, the cluster for adjusting the shortage of the number of clusters at the time of recording the stream C2 obtained at the start of re-encoding. Assuming that the number is K1, (K1- (Nr-1)) (= (K1-1) -Nr) clusters remain without being used for recording the stream C2. , Each G included in the portion of the stream C2 stored in the memory 50 and recorded in the portion of the stream C2 recorded on the recording medium 48. You may make it distribute equally with OP by the ratio of the number of pictures of each GOP.

  When the end position of the re-encoding section is not the end position of the GOP, for example, from the start position of the re-encoding section to a predetermined GOP and further to the first I picture in the display order in the next GOP of the GOP. When one or a plurality of B pictures are used as a re-encoding section, these B pictures are included in the immediately preceding GOP, and the remaining clusters are also considered in the number of those B pictures, Prorated by the ratio of the number of pictures.

  Returning to the flowchart of FIG. 15, when the remaining clusters are allocated, the process proceeds to step S56. In step S56, the dummy data insertion unit 129 adds dummy data to the stream of the re-encoding section including the IN point, which is stored in the memory 50, according to the number of clusters allocated to each GOP in the process of step S55. insert.

  For example, when the stream C2 shown in FIG. 16B is stored in the memory 50 and two clusters are allocated to each of GOPA1 and GOPB1, the dummy data insertion unit 129 has the last part of GOPA1 indicated by the arrow H2, In addition, dummy data for two clusters, that is, dummy data having a size of 2CS (where CS is the cluster size) is inserted into the last portion of GOPB1 indicated by the arrow H3 and stored in the memory 50. As a result, the size of the stream C2 composed of GOPA1 and GOPB1 is just the size of data that can be recorded in the cluster number CLI allocated to the stream C2.

  In step S57, the encoding control unit 128 controls the decoding and encoding of the re-encoding section including the OUT point and the connection of the OUT point. That is, the stream acquisition control unit 125 transmits the stream B2 from the position γ2 to the position OUT3 based on the control signal sent from the CPU 41 via the north bridge 42, the PCI bus 44, the PCI bridge 49, and the control bus 51. A portion of the compressed video data is decoded by the decoder 55, a portion of the compressed video data from position OUT2 to position δ2 of the stream A2 is decoded by the decoder 54, and the effect / switch 58 converts each video signal obtained by the decoding. The operation of the effect / switch 58 is controlled so as to be encoded by the encoder 59 after being connected at the OUT point and subjected to an effect as necessary, and the decoder 54 and the decoder 55 are controlled with respect to the decoding control unit 126. Instructs decoding control in Then, it instructs the encoding control unit 128 to control the encoding of the video signal in the encoder 59.

  Further, the decoding control unit 126 controls the decoding of the compressed video data in the decoder 54 and the decoder 55 in accordance with the instruction from the stream acquisition control unit 125, and the encoding control unit 128 includes the code amount calculation unit 142 for the stream D2. The encoding of the video signal in the encoder 59 is controlled so as to be encoded at the bit rate obtained by the above.

  Further, at this time, the encoding control unit 128 inserts a sequence header at the head of each GOP constituting the stream D2 in accordance with the setting of the apparatus for reproducing the insert edited stream, and the stream D2 is added to the sequence header. The encoder 59 is controlled so that the value of VBV Delay at the time of encoding or the value 0xFFFF of VBV Delay for reproducing the stream D2 as VBR is inserted.

  When each of the stream acquisition control unit 125, the decoding control unit 126, and the encoding control unit 128 controls the respective units, the stream A2 and the stream B2 supplied to the decoder 54 and the decoder 55 are decoded by the decoder 54 and the decoder 55, respectively. And supplied to the effect / switch 58. Then, the stream A2 and the stream B2 to be re-encoded are connected to the OUT point, that is, the position OUT2 and the position OUT3 by the effect / switch 58 to become the stream D2, and supplied to the encoder 59. Further, the stream D2 supplied to the encoder 59 is re-encoded by the encoder 59, supplied to the memory 50 via the stream splicer 57 and the PCI bridge 49, and stored.

  In step S58, the dummy data insertion unit 129, for each GOP included in the re-encoding section including the OUT point, among the CLO clusters assigned to the re-encoding section, the remaining clusters. To distribute.

  In step S59, the dummy data insertion unit 129 adds dummy data to the stream of the re-encoding section including the OUT point, which is stored in the memory 50, according to the number of clusters allocated to each GOP in the process of step S58. Insert, and the process ends. When the re-encoding of the re-encoding section is completed, the stream acquisition control unit 125 generates a signal indicating that the re-encoding is completed, and the stream acquisition control unit 125 passes the control bus 51, the PCI bridge 49, the PCI bus 44, and the north bridge 42. Supply to CPU41.

  In this way, the editing apparatus 31 calculates the target code amount of the stream in the re-encoding section so that the re-encoded stream can be recorded with the number of clusters allocated to the re-encoding section, and the code Re-encode the stream to target the amount.

  In this way, the target code amount of the stream in the re-encoding section is calculated so that the re-encoded stream can be recorded with the number of clusters allocated to the re-encoding section, and the stream is set with the target code amount as the target. By re-encoding, the overwrite data can be surely recorded in the portion of the base data that is replaced with the overwrite data. Therefore, even when the remaining recording capacity that can be recorded on the recording medium 48 is small, insert editing can be performed.

  In addition, when the stream obtained by editing is recorded in an area where the background data of the recording medium 48 is not recorded, new data is recorded on the recording medium 48 while the insert editing is performed several times. Re-encoding section so that overwritten data can be recorded reliably in the part that is replaced with the overwritten data in the base data, but the data to be inserted after editing cannot be recorded. By determining the code amount of the stream, insert editing can be performed any number of times.

  As described above, the number of clusters that can be used in the re-encoding section is obtained, and the target code amount of the stream in the re-encoding section is calculated so that the re-encoded stream can be recorded with the number of clusters. Since the stream is re-encoded so that the calculated code amount is obtained, the overwrite data can be surely recorded in the overwritten portion of the background data.

  The background data recorded on the recording medium 48 may be data encoded by CBR or may be data encoded by VBR, but the background data is data encoded by VBR. In this case, since the code amount may be locally smaller than that in the case of encoding by CBR, it is preferable that the data is encoded by CBR.

  In the above description, the case where MPEG is used as an image compression method has been described as an example. However, the present invention is applicable even when processing is performed using another image compression method involving frame correlation. Needless to say. For example, AVC (Advanced Video Coding) / H. In the case of H.264, the present invention is applicable.

  Further, in the above description, the CPU 41 and the CPU 52 have been described as transmitting and receiving control signals, sharing them, and performing control. However, for example, the same processing is performed using one CPU. Also good.

  The series of processes described above can be executed by hardware or can be executed by software. When a series of processing is executed by software, a program constituting the software may execute various functions by installing a computer incorporated in dedicated hardware or various programs. For example, it is installed from a program recording medium in a general-purpose personal computer or the like.

  FIG. 17 is a block diagram illustrating an example of the configuration of a personal computer that executes the above-described series of processing using a program. The CPU 311 of the personal computer 301 executes various processes according to a program recorded in a ROM (Read Only Memory) 312 or a recording unit 318. A RAM (Random Access Memory) 313 appropriately stores programs executed by the CPU 311 and data. The CPU 311, ROM 312, and RAM 313 are connected to each other via a bus 314.

  An input / output interface 315 is also connected to the CPU 311 via the bus 314. The input / output interface 315 is connected to an input unit 316 including a keyboard, a mouse, and a microphone, and an output unit 317 including a display and a speaker. The CPU 311 executes various processes in response to commands input from the input unit 316. Then, the CPU 311 outputs the processing result to the output unit 317.

  The recording unit 318 connected to the input / output interface 315 includes, for example, a hard disk, and records programs executed by the CPU 311 and various data. The communication unit 319 communicates with an external device via a network such as the Internet or a local area network.

  A program may be acquired via the communication unit 319 and recorded in the recording unit 318.

  The drive 320 connected to the input / output interface 315 drives a removable medium 331 such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory, and drives the program or data recorded therein. Get etc. The acquired program and data are transferred to the recording unit 318 and recorded as necessary.

  As shown in FIG. 17, a program recording medium for storing a program that is installed in a computer and can be executed by the computer is a magnetic disk (including a flexible disk), an optical disk (CD-ROM (Compact Disc-Read Only Memory), DVD (including Digital Versatile Disc), magneto-optical disk), or removable media 331 which is a package medium made of semiconductor memory, or ROM 312 in which a program is temporarily or permanently stored, The recording unit 318 is configured by a hard disk or the like. The program is stored in the program recording medium using a wired or wireless communication medium such as a local area network, the Internet, or digital satellite broadcasting via a communication unit 319 that is an interface such as a router or a modem as necessary. Done.

  In the present specification, the step of describing the program stored in the program recording medium is not limited to the processing performed in time series in the described order, but is not necessarily performed in time series. Or the process performed separately is also included.

  The embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

It is a figure for demonstrating cut edit. It is a figure for demonstrating insert edit. It is a figure explaining cluster management at the time of recording of a stream. It is a block diagram which shows the hardware constitutions of the editing apparatus to which this invention is applied. It is a block diagram which shows the structural example of the function of an editing apparatus. It is a block diagram which shows the more detailed structural example of a control part. It is a figure explaining the number of clusters with respect to the code amount of a flame | frame. It is a figure explaining the transition of the VBV buffer of background data. It is a figure explaining the transition of the VBV buffer at the time of re-encoding. It is a figure explaining the transition of the VBV buffer at the time of re-encoding. It is a figure explaining the transition of the VBV buffer at the time of re-encoding. It is a flowchart explaining the process of CPU. It is a figure explaining the number of clusters which can be used for a re-encoding area. It is a figure explaining a re-encoding area. It is a figure explaining the process of CPU. It is a figure explaining distribution of the remaining clusters. And FIG. 16 is a block diagram illustrating a configuration example of a personal computer.

Explanation of symbols

  31 editing device, 41 CPU, 46 HDD, 47 drive, 48 recording medium, 52 CPU, 54 to 56 decoder, 58 effect / switch, 59 encoder, 91 control unit, 92 acquisition unit, 121 operation input acquisition unit, 122 re-encoding Section determination unit, 123 parameter transmission unit, 124 stream transmission control unit, 125 stream acquisition control unit, 126 decoding control unit, 127 parameter acquisition unit, 128 encoding control unit, 129 dummy data insertion unit, 141 cluster number calculation unit, 142 Code amount calculation unit

Claims (10)

In an information processing apparatus that performs re-encoding by setting a target code amount when recording a second encoded stream in a predetermined section of the first encoded stream recorded on a recording medium,
The first encoded stream from the first position before the IN point that is the start position of the predetermined section to the second position after the OUT point that is the end position of the predetermined section. Recording from the first number of clusters required for recording and the third position near the start position of the second encoded stream to the fourth position near the end position of the second encoded stream And the second number of clusters required for
The video signal obtained by decoding the first encoded stream from the first position to the IN point, and the second signal from the start position of the second encoded stream to the third position. A first video signal connected to a video signal obtained by decoding the encoded stream, and the second encoded stream from the fourth position to the end position of the second encoded stream. For recording a second video signal obtained by decoding the video signal obtained by decoding the video signal obtained by decoding the first encoded stream from the OUT point to the second position. Cluster number calculating means for calculating a third number of clusters that can be used;
Re-encoding means for re-encoding the first video signal and the second video signal to generate a first re-encoded stream and a second re-encoded stream;
Code amount calculation means for calculating a target code amount when re-encoding the first video signal and the second video signal using the third cluster number calculated by the cluster number calculation means;
Re-encoding control means for controlling re-encoding by the re-encoding means so that a generated code amount obtained by re-encoding the first video signal and the second video signal becomes the target code amount. Information processing device. The first re-encoded stream generated by the re-encoding means, the second encoded stream from the third position to the fourth position, and the second re-encoded stream are respectively connected The information processing apparatus according to claim 1, further comprising a recording unit configured to record at a position where the first encoded stream from the first position to the second position is recorded on the recording medium. . The cluster number calculating means can be used for recording the fourth video signal that can be used for recording the first video signal and the second video signal by using the third cluster number. Further determining the fifth cluster number,
The code amount calculation means includes:
The target code amount of the first video signal is calculated based on a sixth cluster number obtained by subtracting one less than the number of pictures of the first video signal from the fourth cluster number. Calculate
The target code amount of the second video signal is calculated based on a seventh cluster number obtained by subtracting one less than the number of pictures of the second video signal from the fifth cluster number. The information processing apparatus according to claim 1. The information processing according to claim 3, wherein the first encoded stream, the second encoded stream, the first re-encoded stream, and the second re-encoded stream conform to an MPEG standard. apparatus. The code amount calculation means includes:
The difference between the VBV (Video Buffering Verifier) buffer occupancy at the first position and the VBV buffer occupancy at the third position is subtracted from a value obtained by multiplying the sixth cluster number by the cluster size. The value obtained as a result is calculated as the target code amount of the first video signal,
Obtained by subtracting the difference between the VBV buffer occupancy at the fourth position and the VBV buffer occupancy at the second position from the value obtained by multiplying the seventh cluster number by the cluster size. The information processing apparatus according to claim 4, wherein the calculated value is calculated as the target code amount of the second video signal. The code amount calculating means further calculates a bit rate when the first video signal is re-encoded using the target code amount of the first video signal, and The information processing apparatus according to claim 5, wherein a bit rate at which the second video signal is re-encoded is calculated using the target code amount. A first remaining cluster number that is a difference between the fourth cluster number and the number of clusters required for recording the first re-encoded stream is obtained, and the first remaining cluster number is calculated as the first remaining cluster number. Distributed to each GOP (Group of Picture) constituting one re-encoded stream, and inserts dummy data for the number of clusters allocated to each GOP at the end of those GOPs,
A second remaining cluster number, which is a difference between the fifth cluster number and the number of clusters required for recording the second re-encoded stream, is obtained, and the second remaining cluster number is calculated as the second remaining cluster number. The information processing according to claim 3, further comprising: an inserting unit that allocates the dummy data corresponding to the number of clusters allocated to each GOP at the end of those GOPs allocated to each GOP constituting the two re-encoded streams. apparatus. In the information processing method of the information processing apparatus for performing re-encoding by setting a target code amount when recording the second encoded stream in a predetermined section of the first encoded stream recorded on the recording medium,
The first encoded stream from the first position before the IN point that is the start position of the predetermined section to the second position after the OUT point that is the end position of the predetermined section. Recording from the first number of clusters required for recording and the third position near the start position of the second encoded stream to the fourth position near the end position of the second encoded stream And the second number of clusters required for
The video signal obtained by decoding the first encoded stream from the first position to the IN point, and the second signal from the start position of the second encoded stream to the third position. A first video signal connected to a video signal obtained by decoding the encoded stream, and the second encoded stream from the fourth position to the end position of the second encoded stream. For recording a second video signal obtained by decoding the video signal obtained by decoding the video signal obtained by decoding the first encoded stream from the OUT point to the second position. Calculate the number of third clusters that can be used,
Using the calculated third cluster number, a target code amount for re-encoding the first video signal and the second video signal is calculated,
Re-encoding of the first video signal and the second video signal is performed so that a generated code amount obtained by re-encoding the first video signal and the second video signal becomes the target code amount. Control
An information processing method including a step of re-encoding the first video signal and the second video signal to generate a first re-encoded stream and a second re-encoded stream. For causing a computer to execute information processing for setting a target code amount and performing re-encoding when recording a second encoded stream in a predetermined section of the first encoded stream recorded on a recording medium A program,
The first encoded stream from the first position before the IN point that is the start position of the predetermined section to the second position after the OUT point that is the end position of the predetermined section. Recording from the first number of clusters required for recording and the third position near the start position of the second encoded stream to the fourth position near the end position of the second encoded stream And the second number of clusters required for
The video signal obtained by decoding the first encoded stream from the first position to the IN point, and the second signal from the start position of the second encoded stream to the third position. A first video signal connected to a video signal obtained by decoding the encoded stream, and the second encoded stream from the fourth position to the end position of the second encoded stream. For recording a second video signal obtained by decoding the video signal obtained by decoding the video signal obtained by decoding the first encoded stream from the OUT point to the second position. Calculate the number of third clusters that can be used,
Using the calculated third cluster number, a target code amount for re-encoding the first video signal and the second video signal is calculated,
Re-encoding of the first video signal and the second video signal is performed so that a generated code amount obtained by re-encoding the first video signal and the second video signal becomes the target code amount. Control
A program including the step of re-encoding the first video signal and the second video signal to generate a first re-encoded stream and a second re-encoded stream. For causing a computer to execute information processing for setting a target code amount and performing re-encoding when recording a second encoded stream in a predetermined section of the first encoded stream recorded on a recording medium A program,
The first encoded stream from the first position before the IN point that is the start position of the predetermined section to the second position after the OUT point that is the end position of the predetermined section. Recording from the first number of clusters required for recording and the third position near the start position of the second encoded stream to the fourth position near the end position of the second encoded stream And the second number of clusters required for
The video signal obtained by decoding the first encoded stream from the first position to the IN point, and the second signal from the start position of the second encoded stream to the third position. A first video signal connected to a video signal obtained by decoding the encoded stream, and the second encoded stream from the fourth position to the end position of the second encoded stream. For recording a second video signal obtained by decoding the video signal obtained by decoding the video signal obtained by decoding the first encoded stream from the OUT point to the second position. Calculate the number of third clusters that can be used,
Using the calculated third cluster number, a target code amount for re-encoding the first video signal and the second video signal is calculated,
Re-encoding of the first video signal and the second video signal is performed so that a generated code amount obtained by re-encoding the first video signal and the second video signal becomes the target code amount. Control
A recording medium on which a program including a step of re-encoding the first video signal and the second video signal to generate a first re-encoded stream and a second re-encoded stream is recorded.

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