JP3976045B2 - Authoring system and method - Google Patents

Description

The present invention relates to an authoring system and method suitable for application to an authoring system for data such as digital video and audio for producing a medium such as a digital video disc.

  Random access of disc players is called “track”, which has been familiar since CD-DA (Compact Disk-Digital Audio), which is more commonly applied in the case of true random access. There is access in units, or access in units called “chapter” on a laser disc. In a CD, a track usually corresponds to one piece of music, and a “chapter” in a laser disc corresponds to each scene. Further, in recent VIDEO CD (video CD), the concept of the track is further developed, and the entire stream is divided into playback unit parts called PLAY ITEM (play item), which is called PLAY LIST (play list). There is also a new random access mechanism called PLAYBACK CONTROL that reproduces in the order of PLAY ITEM described in the list (in an order different from the recording order on the disk).

For example, access by truck is generally realized by the following mechanism.
1. At the time of encoding (sometimes called authoring or mastering), the start point of each track is designated by a time code. For example, it is assumed that the track number increases sequentially from the first.
2. When encoding, remember where the video or audio data corresponding to the time code specified by a certain track number was recorded on the disc by the absolute address method used in the disc format. . {In the case of CD, the absolute time code is planned to be used, and in the case of DVD (Digital Video Disk), the use of a sector address is scheduled. }
3. When the track number / disk address pair information is completed for all track starting points, it is used as the TOC (Table Of Contents) in the vicinity of the first physical location on the disk (usually the disk Place it on the innermost circumference.
4). If the player reads this TOC and stores it in the memory, etc., when the user designates a track, the absolute address on the disc is immediately identified, so the pickup is directly advanced to that address for playback. You can read the first data of the track that should be.

  The DVD player will also inherit these functions and be equipped with a random access function based on track (or chapter) numbers and a random access function based on PLAYBACK CONTROL. The object in the following description is a random access function for the points specified in this way. For the sake of simplicity, these functions will be referred to as a “cue function” and a specific location on a disk that is randomly accessed will be referred to as a “cue point”.

  Random access is performed from the middle of the recorded stream by performing random access when playing a disc on which a video signal of MPEG2 (Moving Picture Engineering Group-2) restricted by GOP (Group Of Pictures) is recorded. Even in this case, unlike normal signals, playback of normal video cannot be started from an arbitrary picture. Due to the nature of MPEG image compression, it is always necessary to read an intra picture (I picture) called a reference picture first, which leads to a head search in GOP units.

  On the other hand, in normal MPEG2 encoding, it is known that it is efficient that 1 GOP is composed of 12 to 15 pictures (frames). Therefore, if encoding is performed only with the rule of 1 GOP = 12 to 15 pictures, the above-described points that can be cued during reproduction can be obtained only every 12 to 15 pictures. However, it is obvious that points that are candidates for cueing such as breaks in scenes of videos and movie works may appear every 12 to 15 frames, and appear at any place.

  If the cue point is to be determined most easily, there is a method of selecting the GOP cut at the nearest location and setting it as the cue point instead of selecting a cut with meaning in the work. (The current VIDEO CD is this method.) However, if the complexity of compression encoding is not considered, the rule of GOP usually composed of every 12 to 15 pictures is broken, for example, near the cue point. It is possible to bring the cue point to the end of the GOP.

  However, this alone does not solve the problem. Just by setting the cue point as a GOP break, there is no guarantee that playback will start from the picture intended by the work after random access. This is due to the way the pictures are arranged in the GOP.

  The above will be described in detail with reference to FIG. FIG. 8 shows a general MPEG image sequence. FIG. 8 shows a cut out part of a continuous long image, and the type of image that is compressed and encoded into the original image and the order in which the original image is arranged. A typical example is used. 8A shows the original image, FIG. 8B shows the encoder output, FIG. 8C shows the decoder input, and FIG. 8D shows the reproduced image.

[GOP is not completely independent]
In the legend in FIG. 8, an I picture is an image that can be reproduced independently, and a P picture is an image using prediction from an I or P picture ahead (in the past). A B picture is an image that uses both prediction from an I or P picture that is ahead (past) than itself and prediction from an I or P picture that is behind (future). Note that the numbers “xx” attached to I, B, and P indicate the order of the screens in the original image, and the smaller numbers indicate the past and the larger numbers indicate the future. A solid line arrow indicates a relationship of which image is predicted from which image.

  As shown in FIG. 8A, the original image 1 input to the encoder is sequentially compressed and encoded in the order of “... BBPBBIBBPBBPBBIBB. As indicated by solid arrows, forward prediction from forward or backward, for example, forward prediction from I2 picture is used for 3 images of B3 picture, B4 picture and P5 picture, and at the same time, for B3 picture and B4 picture, Backward prediction from P5 pictures is also used.

  As shown in the encoder output shown in FIG. 8B, the image data subjected to the compression encoding is rearranged for convenience in decoding. For example, the I2 picture on the original picture is placed at the position shown in FIG. 8B, but the B3 picture and the B4 picture are respectively shifted to the back and placed at the positions behind the P5 picture. By doing so, as shown in the decoder input of FIG. 8C, the I2 picture and the P5 picture necessary for reproducing the B3 picture and the B4 picture can be decoded first. Note that, in the encoder output shown in FIG. 8B, a portion from the I picture to the front of the next I picture is called a GOP.

  Attention should be paid here to the reproduction of the B0 picture and the B1 picture shown in the reproduction image of FIG. 8D. From the point of view of GOP, these B0 and B1 pictures are included in the same GOP N as I2, but for reproduction, the GOP is moved to the previous GOP as shown by the solid arrow in FIG. 8C. This is a point that requires prediction from the included P1 picture. With this, it is said that “GOP is not completely independent”.

  Furthermore, an important point is that the top image in the normal GOP is a B0 picture when viewed in the order of the original images.

[Problems in cue playback]
Next, a problem that occurs because the GOP is not completely independent will be described with reference to FIG. FIG. 9 is an explanatory diagram showing a problem when the head of a certain GOP N is used as a cue point. FIG. 9A shows a decoder input, and FIG. 9B shows a reproduced image. Now, it is assumed that there is a series of GOPs that are continuously compression-encoded and input to the decoder. Now, it is assumed that the player performs a cueing operation on such a GOP row. It is assumed that the cue point at which the pickup of the player at this time is located is the I2 picture that is the head when viewed from the GOPN decoder input.

  At this time, in order to reproduce the B0 picture and the B1 picture, not only the backward prediction from the I2 picture but also the forward prediction from the P1 picture is required, but the data before the cue point is not read out. Therefore, the prediction from the P1 picture indicated by the dashed arrow in FIG. 9A cannot be used. In other words, there is no problem when continuous sequential playback is performed, but when the head is found at a certain place, “prediction from the last P picture of the previous GOP” cannot be used. Therefore, as a result, in the reproduced image shown in FIG. 9B, some of the first B pictures (in this case, B0 and B1) in GOP N cannot be reproduced, and the reproduction can be started. Becomes from the I2 picture.

  Originally, at the time of encoding, the first picture of GOP N is a B0 picture. In this example, even if the specified GOP data can be picked up, the cue point is consequently two frames behind. It will shift to.

  As described above, there are some problems in cue playback. The following can be considered as a solution to this problem.

[Solution 1 seems to be correct at first glance]
* Offset the cue point from the beginning of the GOP.
For example, the picture that you want to cue at the beginning of the track is not the beginning of GOP N, but rather it is shifted from the beginning to specify the I picture as the cue point and match the playback start point. It seems that it is not, but that does not solve the following problem.

1. The problem that it is not uniquely determined how much to shift from the top of the GOP.
According to the rules of MPEG2, there is no restriction on the number of B pictures (I pictures, or the interval between I pictures and P pictures, or the number of M if MPEG terms are used). In view of image quality and code efficiency, the number of B pictures can be arbitrarily selected. Therefore, it cannot be said that it is impossible to encode how much the cue point should be shifted from the head of the GOP.
Originally I wanted to specify the cue point at a specific position on the work, so I tried to shift the GOP delimiter, but if I did not actually build the GOP after encoding, I could not find the cue point In other words, it falls into the “chicken and egg” relationship.

2. The problem that the cue point cannot be confirmed with the time code. Furthermore, there is a problem with the time code. In MPEG2, a time code cannot be held for each picture. As an option, a GOP header can be arranged at the head of the GOP, and a time code can be put on this GOP header. “Strike” is to record time code data on a recording medium corresponding to the GOP head. Even in the expected DVD format, the shape is different, but it is also possible to enter a time code for each GOP. What should the timecode value be in this case?
When normal sequential playback is considered, if the time code value is uniquely determined regardless of the GOP structure (how many pictures are used), the GOP is considered very naturally. The time code corresponding to the picture to be reproduced and displayed first among the included pictures should be obtained. In the example of FIG. 9, if the B0 picture is the first image to be reproduced in GOP N if it is sequentially reproduced from the beginning of the data string, the time code to be attached to GOP N Is a value of time “t = 0” of the B0 picture.
In that case, when the cueable point becomes the intra picture I2 which is not the top when viewed in the display order in GOP N, the time code corresponding to it is a value of “t = 2”, but the value itself is GOP. Data associated with N does not exist in the data stream. Originally, the cue point specified by the time code (in this example, “t = 2” of the I2 picture), but if the time code does not finally exist in the stream as data, It becomes difficult to confirm from the data itself whether or not is correctly encoded. Furthermore, the cue point is expressed as a pair of a time code and a recording address on the disc where the cue point is recorded, and the search is performed even when viewed from a conventional “cue point search system” in which it is registered in the TOC. Even if the information located at the address of the data on the side is read out, the time code that should accompany it cannot be confirmed directly.
In addition, the fact that a point that is always advanced by a fixed value frame from the time code attached to the GOP is used as a cue point results in a problem 1.

  Here, the problems described above are summarized. The method of setting the cue point of a track or the like as the first intra picture existing in the GOP is a special case in which the value of “M” is fixed to 3 (for example, the problem of the TOC is “deviation”). In general, the value of “M” is arbitrary, so even if you specify the cue point at the time of encoding, the image that is actually cued It is difficult to determine uniquely.

[Solution 2 seems to be correct at first glance]
* Method for Applying CLOSED GOP FIG. 10 is an explanatory diagram showing the concept of “CLOSED GOP” in MPEG2. 10A shows an original image, FIG. 10B shows an encoder output, FIG. 10C shows a decoder input, and FIG. 10D shows a reproduced image.

  CLOSED GOP does not use “prediction from the last I or P picture of the previous GOP”, but encodes the first several B pictures in the GOP in the original screen order. The idea is to ensure the independence of the GOP by coding so as to predict only from the immediately following I picture (Only Backward Prediction). In view of the encoder output in FIG. 10B, such a GOP N is called a CLOSED GOP. As shown in FIG. 10C, if the player's cue point is a CLOSED GOP, the decoder input does not require forward prediction from the previous GOP as indicated by the dashed arrow in the figure. In the reproduced image shown in FIG. 10D, some B pictures immediately after the I2 picture (in this example, B0 and B1 shown in FIG. 10D) use only backward prediction from the I2 picture, In theory, reproduction is possible.

  This is a good solution at first glance, but it is not a complete solution. In MPEG2, CLOSED GOP is said to be reproducible from the B0 picture at the head when viewed in the display order at the time of reproduction, but it is not said that it must be reproduced.

  In the example of FIG. 10, a normal player must first read an I2 picture and decode it immediately after cueing. This I2 picture becomes a reference, and the next decoding is possible. At this time, the following matters.

  Do not display the decoded I2 picture immediately, wait for decoding of the B0 picture, and then display from the first picture (B0 picture) in the order of display in this GOP, or immediately display the I2 picture It is completely arbitrary whether the previous B1 picture is skipped in time and continued to the next B3 picture. (Actually, at the playback start point of the cue point, since the decoding buffer is empty, it seems that there are many players that first play the I picture. The reason is that the control becomes simple. (In order to avoid the appearance that the access speed appears to be slow because the playback image cannot be displayed during the time for decoding at least some of the B pictures.)

  Therefore, even if the cue point of a track or the like is a CLOSED GOP at the time of encoding, it is not always reproduced from the first picture in the display order in the GOP at the time of reproduction. However, such a reproduction method is not violated by rules defined by MPEG.

  Under such circumstances, at present, there is no encoding method for reliably specifying the cue point, and from which picture cue reproduction is performed is freely performed by each player.

The present invention has been made in consideration of such points, and proposes an authoring system and method capable of performing stable reading at the time of reproduction by enabling the display image of the cue point to be uniquely determined. It is something to try.

One of the main inventions is an authoring system that encodes a video signal to generate encoded data, and corresponds to the cue point when a cue point for reproducing the video signal is designated. Reference prediction associated with encoding between a delimiter determining unit for determining a delimiter of the new GOP and the new GOP determined by the delimiter determining unit so that the picture becomes the head of the new GOP in the display order. The GOP composing means for determining the picture type of the picture in the new GOP and configuring the new GOP, and the video signal in which the new GOP is composed by the GOP composing means The generated bit amount calculating means for calculating the generated bit amount accompanying encoding, and the generated bit amount calculating means A quantization level control means for adjusting the quantization levels based on the serial number of bits generated in accordance with the adjusted quantization level by the quantization level control means, for encoding the video signal in which the new GOP is constituted Thus, an authoring system having encoding means for generating the encoded data.

According to the above invention, when reproducing the recording medium on which the encoded data generated by encoding the video signal is recorded, the information on the cue point is reproduced at high speed and correctly .

According to the present invention described above, when playing back a recording medium on which encoded data generated by encoding a video signal is recorded, it is possible to uniquely determine a cue point, and to provide a stable cue function. There is an effect that can be done .

Embodiments of the present invention will be described below in detail with reference to the drawings.
[Outline of this embodiment]
For example, in a medium in which digital video and audio data are recorded on a disk-shaped recording medium such as a phase change type optical disk, a magneto-optical disk, and a read-only optical disk such as a DVD, it is performed on a CD. There is a random access function for starting playback from a specific place designated by the user, like the PLAYBACK CONTROL (PBC) function of VIDEO CD, or cuing by track jump. In this embodiment, for example, in compression encoding of an MPEG2 video signal recorded on a DVD, a function of starting playback from a specific place represented by track jump, PLAYBACKCONTROL, etc. (hereinafter referred to as cue playback) is provided. When encoding for a player,
1. A GOP (GROUPOF PICTURE) delimiter is always inserted at the cue point of a break of a track (or PLAY ITEM, which is one playback unit of PLAYBACK CONTROL).
2. In addition, the “sequence with cut” is applied to a GOP corresponding to a cue point such as a break of a track (or PLAY ITEM, which is one playback unit of PLAYBACKCONTROL), and predictions are made forward or backward with respect to each other in pictures before and after that point. Do not need coding. This ensures that the image at the cue point is always an intra picture, so that the picture at the cue point is always uniquely determined regardless of the playback device. Cue playback can be provided.

  Here, “separation” can be a unit between logical units, that is, a boundary between logical sectors, logical tracks, logical blocks, or a physical sector. Examples of logical unit boundaries include boundaries between units intended by the producer, such as tracks on a CD and chapters on a video disc. In addition, as a boundary between physical units, there is a boundary between access units of an optical pickup, such as a physical sector on an optical disk, which is the structure of a recording medium itself.

  In other words, in this embodiment, by applying “a sequence with a cut” and performing encoding so that the display image of the cue point can be uniquely determined in any player, a stable cue function can be achieved. It guarantees the provision. Hereinafter, this embodiment will be described in detail.

  First, a compression encoding method as a base of this embodiment will be described with reference to FIG. 1A shows the normal sequence, FIG. 1B shows the cut sequence, FIG. 1C shows the encoder output, FIG. 1D shows the decoder input, and FIG. 1E shows the reproduced image. Has been.

  As shown in FIG. 1A, in a normal sequence, for example, a P0 picture is followed by a B0 picture, a B1 picture, and an I2 picture. However, in this embodiment, a special sequence is used separately. In the special sequence, as shown in FIG. 1B, the P1 picture is followed by the I0 picture, and from there, the B1 picture and the B2 picture are continued in the same manner as the normal sequence. In this embodiment, such a sequence is called a “cut sequence” or a “cut sequence”.

  Thus, normally, as shown in FIG. 1A, the sequence of “... BBPBBIBBP...” Is “... BBPIBBPBB. Just as in the cut indicated by the solid line arrow in FIG. 1B, it appears that the B picture is missing. By placing this cut, as is apparent from FIG. 1B, there is no original prediction between GOPN-1 and GOP N before and after the cut, so GOP N-1 and GOP N are completely Independent.

* Make the cue point a sequence with a cut. Now, let's look at the case where the beginning of a GOP composed of a sequence with a cut is a cue point such as the beginning of a track. As seen from the decoder input shown in FIG. 1D, the head of the GOP with the cut is the I0 picture (the first image to be displayed in the GOP is an intra picture). However, it is clear that both images are the first images when viewed in the order of the reproduced images shown in FIG. 1E.

This is one of the points in this embodiment. If you want to specify a specific location as the cue point during playback, such as a track or PLAYBACKCONTROL function, The GOP delimiter is determined so that the image corresponding to the cue point becomes the head of the GOP in the display order.
2. The GOP is composed of a cut sequence.
In the image data compression-encoded according to this rule, when reproduction is started from the cue point indicated by the solid line arrow in FIG. 1D, there is a relationship of “first decoded image = first displayed image”. Therefore, any playback device must be played back from the I0 picture. Therefore, the cue point can be uniquely determined. Furthermore, since the time code associated with the cue point image can be applied as it is as the time code associated with the GOP, it can be determined whether the cue point can be encoded at the correct position by looking at the encoded time code. Therefore, it can be easily determined.

  In other words, the cue point is represented by a pair of the time code and the recording address on the disc where the cue point is recorded, and the search is performed even when viewed from the conventional “cue point search system” in which it is registered in the TOC. If the information located at the address of the data on the side is read, the time code to be attached to it can be directly confirmed.

[Overview of configuration and operation]
FIG. 2 shows a configuration example of an authoring system as one embodiment. First, a master tape (video tape cassette used as a master) 1 to be compression-encoded is reproduced by a digital VTR 2. The flexible disk 6 on which data with each cue point designated by a time code written to the master tape 1 is set in a cue point reading unit 7. The read cue point information can be further finely adjusted, added or deleted by the cue point correcting device 8. Information on the time code of the cue point for the master tape 1 determined by the above means is sent to the cut determination circuit 9. A time code is recorded in advance on the master tape 1 reproduced by the digital VTR 2, and the time code data from the digital VTR 2 is supplied to the cut determination circuit 9 and the image type control unit 5, respectively.

  Here, as shown in FIG. 3A, EDL data EDLd (edit list) composed of cut number data and time code data corresponding to the cut number data is recorded on the flexible disk 6. .

  The cut determination circuit 9 compares the input time code information of the cue point with the time code data from the VTR 2 and what compression sequence (how to arrange the I picture, P picture, and B picture) is assembled. It is determined whether it is okay, and a correspondence between each frame number data of the input time code and the picture sequence is prepared. For example, in a sequence in the vicinity where there is no cue point, the normal "... BBPBBIBBP ..." is used, and in the vicinity of the cue point, a "sequence with a cut", that is, "... BBPIBBPBB ..." In other words, the order in which picture types are encoded is determined in advance.

  When the reproduction of the master tape 1 is started, the cut determination circuit 9 takes an image corresponding to the time code as to which picture the image corresponding to the time code is matched with the input time code data and the sequence obtained in advance. Whether the image should be compressed by type is sent to the image type control unit 5 as encoded sequence instruction data. On the other hand, the video signal reproduced by the digital VTR 2 is sent to the image delay device 3. The delay amount is set by the operation unit 4, and the same information is supplied to the image type control unit 5 (the delay amount will be described later). The delayed video signal is supplied to the image type controller 5.

  The image type control unit 5 sends two-dimensional image information of an image generated according to each picture type and a time code delayed in accordance with the processing time to a DCT (Discrete Coordinate Transform) 14. The DCT 10 converts image information from two-dimensional pixels into frequency component information, and outputs image frequency component information divided into each band. The image type control unit 5 also outputs time code data delayed in accordance with the processing delay time at the same time in order to save what amount of information the image of which time has. The time code data is supplied to the quantizer 11. The output of the quantizer 11 is inversely converted into two-dimensional pixel information including a quantization error through the inverse quantizer 12 and the inverse DCT 13 and fed back to the image type control unit 5. Thereby, the image type control part 5 can perform the process which produces | generates the difference signal for B thru | or P picture, what is called a prediction process. The image type controller 5 also performs motion prediction and compensation, but feedback information including quantization error is important information for adapting these processes.

  The quantizer 11 quantizes the frequency band information of the image at a provisional quantization level such that the quantization is performed evenly for each band without particular weighting. The quantized bits are output together with time code data delayed by a time corresponding to the time required for quantization. As a result, a change in the amount of image information for each time can be obtained. Hereinafter, the data indicating the change in the amount of image information for each time is referred to as “difficulty data”.

  Now, to the quantization level control circuit 15, for example, manual data is supplied, and for example, information indicating a temporal change in the amount of image information is given. The quantization level control circuit 15 determines what kind of weighting control is necessary from the input time code data and information indicating the time change of the image information amount, and quantizes the quantization level weighting control signal. To the vessel 11. Usually, when there is no problem in image quality, the quantization level correcting device 16 does not work.

  The quantizer 11 performs quantization for each band in accordance with the quantization level weighting control signal, thereby reducing the amount of information. The quantized bits are supplied to the entropy encoder 17 together with time code data delayed by a time corresponding to the time required for quantization. The entropy encoder 17 further performs entropy encoding, which is a lossless compression method, in order to compress the bit amount. Then, the fixed-length bit string up to the previous stage is converted into a variable-length bit string. From the entropy encoder 17, the final image code converted into the variable length code and the time information indicating the time at which the image is to be displayed are supplied to the output rate determination device 18.

  Based on the time information, the output rate determination device 18 obtains header information such as PES (Packetized Elementary Stream) or PACK, packetizes the input image code, and supplies this to the stream output device 19 as the final code output. To do. On the other hand, the output rate determination device 18 is given a normal encoding instruction from the encoder control unit 23 when starting the encoding. The output rate determination device 18 normally encodes the image code and the time information, which are the information from which the final code is output, into the storage device 22 in order to enable editing for improving the image quality later. It is saved together with the marking information that depends on the result of.

  The final code output is also sent to the monitor decoder 21. The operator can monitor the image quality using this monitor. If there is a problem with the image quality, it is necessary to record in the quantization level correction device 16 time information indicating the time at which the image corresponding to that portion should be displayed. When the normal encoding is completed, the “cut” corresponding to the place having the image quality problem is stored in the time information recorded in the quantization level correcting device 16 and in the cut determination circuit 9. It can be easily obtained from the relationship between the time code data and the cut.

  Here, the “cut” corresponding to the part where the image quality is a problem is reproduced again from the encoder control unit 23, and the weight of the quantization level is adjusted in the quantization level correction device 16 while monitoring the monitor decoder 21. A quantization level that does not cause a problem in image quality is obtained. The obtained quantization level weighting control value needs to be given to the quantization level control circuit 15 together with the time code data corresponding to the “cut”. Of course, when there are a plurality of portions having image quality problems, it is necessary to repeat the above processing.

  In the quantization level control circuit 15, the total amount of generated bits is originally known from the difference data. Accordingly, it is possible to recognize a new total generated bit amount as a result of the quantization level being corrected by the quantization level correction device 16. If the total generated bit amount exceeds the total capacity of the media in advance, specify a “cut” that is unlikely to cause a problem even if the bit amount is reduced. Then, while reproducing the portion in the same manner as described above, the quantization level is adjusted by the quantization level correction device 16 so that the information amount is suppressed.

  When the quantization level of the necessary part is adjusted again in this way, the digital VTR 2 is sequentially reproduced from the encoder control unit 23 so as to encode only the “cut” to be processed. Encoding proceeds in the same way as normal encoding. At this time, the encoder control unit 23 gives the designation of re-encoding to the output rate determination device 18 and the storage device 22 in order to indicate that the encoding result is due to re-encoding. As a result, the image code and time information having improved image quality are recorded in the storage device 22 together with the re-encoding marking information.

  When all re-encoding is completed, the storage device 22 stores all of the image code and time information by normal or re-encoding. Based on the image code and time information, the output rate determination device 18 sequentially packetizes the program from the beginning and supplies it to the stream output device 19 as the final code output. The stream output device 19 outputs the final code output via the output terminal 20.

  Next, an encoding sequence determined by the authoring system will be described with reference to FIG.

  In MPEG, the number of pictures in a GOP is called N, and the period of I or P picture (number of pictures from I picture to the next P picture) is called M. In MPEG, there are no restrictions on N and M, but for the sake of explanation, the normal sequence is N = 9 and M = 3. In FIG. 4, an I picture surrounded by a square indicates that it is the head of a cut sequence, and a circled I picture indicates the head of another general GOP. Note that FIG. 4 only shows the order of the encoding sequence of the picture in the original image (in the figure, the subscripts I, B, and P represent the “number” picture in the original picture). Note that this is not the picture order at the encoder output with the concept of GOP. In the encoder output, as described above, the order of the B pictures is switched, and when viewed in GOP units, the I picture is the first.

  In the case of N = 9, there are a total of nine types of cut sequences from cut sequence 0 to cut sequence 8, as shown in FIGS. However, in any case, the main feature is that the picture type immediately before the I picture (indicated by a square box) in the cut sequence is always a P picture.

[Each sequence (the wavy line in FIG. 4 will be described later)]
In the cut sequence 0, as shown in FIG. 4B, the position of the I picture is shifted two sheets ahead of the normal sequence, and the “number 0” picture becomes the I picture. However, since the immediately preceding picture is a P picture, the GOP starts from the I0 picture and N = 10 up to P9 for convenience of sequence. After that, the normal sequence continues.
In the cut sequence 1, as shown in FIG. 4C, the position of the I picture is shifted by one sheet compared to the normal sequence, and the “No. 1” picture becomes the I picture, and the “No. The picture is normally a B picture, but is a P picture. The GOP starts from the I1 picture, and N = 10 up to P10 for convenience of sequence. After that, the normal sequence continues. Since the immediately preceding GOP includes up to the P0 picture, N = 10 only in that case.

In the cut sequence 2, as shown in FIG. 4D, the position of the I picture is the same position as the normal sequence, and the “No. 2” picture becomes the I picture, but the immediately preceding “No. 0” and “No. 1” The two pictures are usually B pictures, but both pictures are P pictures. The GOP starts from the I2 picture, and N = 10 up to P11 for convenience of sequence. After that, the normal sequence continues. Since the immediately preceding GOP includes up to P0 and P1 pictures, N = 11 only in that case.
In the cut sequence 3, as shown in FIG. 4E, the position of the I picture is shifted backward by one as compared with the normal sequence, and the “No. 3” picture is the I picture. However, the normal sequence is extended to the “No. 2” picture. The GOP starts from the I3 picture, and N = 10 up to P12 for convenience of sequence. After that, the normal sequence continues. Note that the immediately preceding GOP includes up to B0, B1, and P2 pictures, so that N = 12.

In the cut sequence 4, as shown in FIG. 4F, the position of the I picture is shifted backward by two compared to the normal sequence, and the “4th” picture is the I picture. However, the normal sequence is extended to the “No. 2” picture, and the “No. 3” picture immediately before the I4 picture is a P picture. GOP starts from an I4 picture, and N = 10 up to P13 for convenience of sequence. After that, the normal sequence continues. Note that since the immediately preceding GOP includes up to B0, B1, P2, and P3 pictures, N = 13 only in that case.
In the cut sequence 5, as shown in FIG. 4G, the position of the I picture is shifted backward by three compared to the normal sequence, and the “No. 5” picture is the I picture. However, the normal sequence is extended up to the “No. 2” picture, and “No. 3” is the B picture and the “No. 4” picture is the P picture among the two pictures immediately before the I5 picture. GOP starts from an I5 picture, and N = 10 up to P14 for convenience of sequence. After that, the normal sequence continues. Since the immediately preceding GOP includes up to B0, B1, P2, B3, and P4 pictures, N = 13 only in that case.

As shown in FIG. 4H, the cut sequence 6 is a different rule because the previous GOP length becomes too long if the position of the I picture is shifted backward as in the past. Placed, followed by a sequence with a new cut. The normal sequence starting from the B0 picture is terminated at N = 6 up to the P5 picture, and the subsequent “No. 6” picture is the I picture of the sequence with the cut. GOP starts from an I6 picture, and N = 10 up to P15 due to the sequence. After that, the normal sequence continues.
As shown in FIG. 4I, the cut sequence 7 is a different rule because the length of the previous GOP becomes too long if the position of the I picture is simply shifted backward, just like the cut sequence 6. The normal sequence is placed, followed by a sequence with a new cut. The normal sequence starting from the B0 picture is continued until the P5 picture, and the P picture is continued to “6th” thereafter, where the GOP is aborted at N = 7. The “No. 7” picture immediately after that is the I picture of the cut sequence. The GOP starts from the I7 picture, and N = 10 up to P16 for convenience of sequence. After that, the normal sequence continues.

  As shown in FIG. 4J, the cut sequence 8 is a different rule because the length of the previous GOP becomes too long if the position of the I picture is simply shifted backward, just like the cut sequence 7. The normal sequence is placed, followed by a sequence with a new cut. The normal sequence starting from the B0 picture is continued until the P5 picture, and the subsequent “No. 6” is set as the B picture, and the “No. 7” is followed by the P picture. Here, the GOP is terminated at N = 8. Immediately after that, the “No. 8” picture is the I picture of the cut sequence. GOP starts from an I8 picture, and N = 10 up to P17 for convenience of sequence. After that, the normal sequence continues.

  The above-described normal sequence data Sd and a total of 10 patterns of sequence data Sd from the cut sequence 0 to 8 are stored in the internal ROM 9a of the cut determination circuit 9 shown in FIG. Then, the cut determination circuit 9 loads normal sequence data Sd from the internal ROM 9a to the internal RAM 9b at the start of processing, and thereafter cues in the constituent image of the GOP next to the GOP being processed. Determine if there is a dot.

  If the cut determination circuit 9 determines that there is no cue point in the next GOP, the cut sequence circuit 9 loads the normal sequence data Sd from the internal ROM 9a to the internal RAM 9b, and the sequence data Sd is loaded into the sequence list data SLd. Used in the next GOP processing. If the cut determination circuit 9 determines that there is a cue point in the next GOP, it detects the number of the cue point from the last component image of the GOP being processed. If the value is “1”, the sequence 0 data is read from the internal ROM 9a, the sequence 2 data is read from the internal ROM 9a. The sequence data Sd is loaded into the internal RAM 9b as sequence list data SLd and used in the next GOP processing.

  FIG. 3B shows an example of the sequence list data SLd. As shown in FIG. 3B, the sequence list data SLd is obtained by registering time code data and picture type data for numbers as addresses. The sequence data Sd corresponds to the picture type data in the sequence list data SLd. Since the smallest value of the time code data is a frame, it goes without saying that the time code data can be obtained continuously by simply incrementing the digit of this frame.

  That is, the cut determination circuit 9 generates time code data for 2 GOP, for example, and registers the generated time code data for 2 GOP in the sequence list data SLd. First, normal sequence data Sd is read from the internal ROM 9a and registered in the sequence list data SLd in correspondence with the time code data. Thereafter, the cut determination circuit 9 includes time code data having the same value as the time code data of the cue point registered in the EDL data EDLd in the time code data corresponding to the next GOP. Detect whether or not. If not included, the cut determination circuit 9 registers the normal sequence data Sd read from the internal ROM 9a in association with the time code data corresponding to the next GOP. If it is included, the cut determination circuit 9 counts the number of images from the last image of the GOP being processed to the image at the cue point of the next GOP on the sequence list data SLd, and according to the value As described above, the data from the sequence 0 to 8 is selected, the selected sequence data Sd is loaded from the internal ROM 9a to the internal RAM 9b, and the load data is used in the processing for the GOP. Here, “use load data” means that the cut determination circuit 9 sends an image from the digital VTR 2 to the image type control unit 5 in the picture type registered in the sequence list data SLd for the time code data of the image. This means that processing is instructed with the picture type indicated by the data.

  Here, FIG. 2 will be described again. In the cut determination circuit 9, based on the information input to the cue point reading unit 7 and the information added and changed by the cue point correction device 8, which time code frame is the cue point, that is, where to cut It has been determined whether to put. Therefore, in the vicinity of the cut, it can be easily determined which of the above-described cut sequences should be selected.

  The cut determination circuit 9 simply and repeatedly gives the encoding sequence instruction data to the image type control unit 5 in the order of the normal sequence when there is no normal cut, and in the vicinity of the cut, the cut sequences 0 to 8 are provided. The pattern data that matches one of the above is given.

  Now, the delay amount of the image delay device 3 will be described. Unless otherwise specified, the image type control unit 5 always places two B pictures when an I or P picture is instructed, and always places an I or P picture after two B pictures. (Ie, the period M of the I or P picture is 3). However, if a sequence is specified in advance, it is encoded as it is.

  That is, when it is desired to perform encoding other than this basic normal sequence, it is only necessary to know in advance that it is different from the normal sequence. Therefore, the image type control unit 5 determines the time code data and the encoding instruction without delay. I need data. Now, although it is a necessary delay amount, let us return to FIG. 4 and pay attention to the “dashed line” portion. This wavy line is a simple rule of a normal sequence, that is, “If an I or P picture is instructed, two B pictures will always follow, and if two B pictures continue, an I or P picture will always be placed next”. The part where a rule is not applied is shown.

  As can be seen from FIG. 4, it can be seen that the effect of placing this cut is 3 frames at the maximum when the period M of the I or P picture is 3, so that the amount of delay for the image delay device 3 is reduced. It can be seen that the set value may be 3 frames. The set delay amount information is also input to the image type control unit 5 at the same time. Therefore, as a result, the image type control unit 5 uses a delay video signal with a known delay amount, time code data without delay, and encode sequence instruction data in a sequence different from normal (in the case where M = 3 is not satisfied). When encoding must be performed, it is possible to know from which frame the specific encoding should be performed from the previous frame.

[Description of main operations in the authoring system shown in FIG. 2]
Next, main operations in the authoring system shown in FIG. 2 will be described with reference to FIGS.

In step S1, the cue point reading unit 7 shown in FIG. 2 reads the EDL data EDLd recorded on the flexible disk 6. The EDL data EDLd read by the cue point reading unit 7 is supplied to the cut determination circuit 9 and held in the RAM of the cut determination circuit 9.
In step S2, the cut determination circuit 9 shown in FIG. 2 reads the time code data registered for the first cut number data from the EDL data EDLd held in the RAM, and the sequence for the subsequent N frames. List data SLd is generated. For example, time code data for 2 GOPs is generated and held in the internal RAM 9b, and normal sequence data Sd, that is, picture type data is read from the internal ROM 9a, and the picture type data is read from the head stored in the internal RAM 9b. Registration is made corresponding to the time code data for GOP. It should be noted that the registration of picture type data for the time code data registered in the sequence list data SLd for the next GOP is performed after processing the last image of the first GOP, as described above. This is performed after the sequence data Sd is selected according to the presence or absence.

In step S3, the cut determination circuit 9 shown in FIG. 2 starts encoding.
In step S4, the cut determination circuit 9 shown in FIG. 2 reads the time code data from the digital VTR2.
In step S5, the cut determination circuit 9 shown in FIG. 2 compares the read time code data value with the time code data value registered in the sequence list data SLd held in the internal RAM 9b.
In step S6, the cut determination circuit 9 shown in FIG. 2 determines whether or not the value of the read time code data is equal to the value of the time code data corresponding to the end of the current GOP, and “YES”. If there is, the process proceeds to step S7, and if “NO”, the process proceeds to step S9.

In step S7, the cut determination circuit 9 shown in FIG. 2 reads the last time code data and picture type data of the GOP being processed from the sequence list data SLd held in the internal RAM 9b, and uses this as an encoding sequence. The instruction data is supplied to the image type control unit 5 shown in FIG. The image type control unit 5 uses the time code data supplied as the encoding sequence instruction data and the picture type data to convert the picture signal of the frame at the temporal position indicated by the time code data having the same value as the time code data to the picture Encode with the picture type indicated by the type data.
In step S8, the cut determination circuit 9 shown in FIG. 2 sequentially increments the value from the read time code data value to, for example, 9 frames, and each value is registered in the EDL held in the internal RAM 9b. It is detected whether or not it matches the value of the time code data. At this time, when the cut determination circuit 9 detects a match, the cut determination circuit 9 includes data indicating that the next GOP includes a cue point and data indicating how many frames match from the read time code. If they do not match, data indicating that is stored in the internal RAM 9b.
In step S9, the cut determination circuit 9 shown in FIG. 2 reads the current time code data and picture type data from the sequence list data SLd held in the internal RAM 9b, and uses these data as encoded sequence instruction data. Is supplied to the image type controller 5 shown in FIG. Here, the “current time code data” is time code data of the current processing target image on the sequence list data SLd.

In step S10, the cut determination circuit 9 shown in FIG. 2 determines whether or not the encoding is completed. If “YES”, the process ends. If “NO”, the process proceeds to step S11. Here, whether or not encoding is completed is determined by whether or not all the time code data at the cue point registered in the EDL has been processed.
In step S11, the cut determination circuit 9 shown in FIG. 2 is based on data held in the internal RAM 9b, that is, data indicating that the next GOP includes a cue point, or data indicating that they do not match. Then, it is determined whether or not the next GOP includes a cue point. If “YES”, the process proceeds to step S12, and if “NO”, the process proceeds to step S13.

In step S12, the cut determination circuit 9 shown in FIG. 2 matches the frame number data up to the cue point included in the next GOP held in the internal RAM 9b, that is, the frame number from the read time code. It is detected from the current data how many sheets are counted from the current point.
In step S13, the cut determination circuit 9 shown in FIG. 2 reads normal sequence data Sd from the internal ROM 9a for the next GOP, and registers the sequence data Sd in the sequence list data SLd of the internal RAM 9b.

In step S15, the cut determination circuit 9 determines whether or not the sheet is “1”. If “YES”, the process proceeds to step S16 and the sequence data Sd of the cut sequence 0 stored in the internal ROM 9a. The process proceeds to step S17, where the sequence data Sd of the cut sequence 0 is read, the data is loaded into the internal RAM 9b, and the process proceeds to step S4 again.
In step S18, the cut determination circuit 9 determines whether or not it is the “second” sheet. If “YES”, the process proceeds to step S19, and the sequence data Sd of the cut sequence 1 stored in the internal ROM 9a. The process proceeds to step S17, where the sequence data Sd of the cut sequence 1 is read, the data is loaded into the internal RAM 9b, and the process proceeds to step S4 again.

In step S20, the cut determination circuit 9 determines whether or not it is the “third” sheet. If “YES”, the process proceeds to step S21 and the sequence data Sd of the cut sequence 2 stored in the internal ROM 9a. The process proceeds to step S17, the sequence data Sd of the cut sequence 2 is read, the data is loaded into the internal RAM 9b, and the process proceeds to step S4 again.
In step S22, the cut determination circuit 9 determines whether or not it is the “fourth” sheet. If “YES”, the process proceeds to step S23, and the sequence data Sd of the cut sequence 3 stored in the internal ROM 9a. Is selected, the process proceeds to step S17, the sequence data Sd of the cut sequence 3 is read, the data is loaded into the internal RAM 9b, and the process proceeds to step S4 again.

In step S24, the cut determination circuit 9 determines whether or not it is the “5th” sheet. If “YES”, the process proceeds to step S25, and the sequence data Sd of the cut sequence 4 stored in the internal ROM 9a. Then, the process proceeds to step S17, the sequence data Sd of the cut sequence 4 is read, the data is loaded into the internal RAM 9b, and the process proceeds to step S4 again.
In step S26, the cut determination circuit 9 determines whether or not it is the “6th” sheet. If “YES”, the process proceeds to step S27, and the sequence data Sd of the cut sequence 5 stored in the internal ROM 9a. The process proceeds to step S17, where the sequence data Sd of the cut sequence 5 is read, the data is loaded into the internal RAM 9b, and the process proceeds to step S4 again.

In step S28, the cut determination circuit 9 determines whether or not it is the “7th” sheet. If “YES”, the process proceeds to step S29 and the sequence data Sd of the cut sequence 6 stored in the internal ROM 9a. The process proceeds to step S17, the sequence data Sd of the cut sequence 6 is read, the data is loaded into the internal RAM 9b, and the process proceeds to step S4 again.
In step S30, the cut determination circuit 9 determines whether or not it is the “8th” sheet. If “YES”, the process proceeds to step S31 and the sequence data Sd of the cut sequence 7 stored in the internal ROM 9a. The process proceeds to step S17, the sequence data Sd of the cut sequence 7 is read, the data is loaded into the internal RAM 9b, and the process proceeds to step S4 again.
In step S32, the cut determination circuit 9 determines whether or not the sheet is “9”. If “YES”, the process proceeds to step S33 to store the sequence data Sd of the cut sequence 8 stored in the internal ROM 9a. The process proceeds to step S17, the sequence data Sd of the cut sequence 7 is read, the data is loaded into the internal RAM 9b, and the process proceeds to step S4 again.

[Effects Derived from Modifications and Embodiments]
This method is applicable to all recording MPEG video (or similar video compression). (Every MPEG video recording / playback device, whether MMCD or SD, will be irrelevant to the recording medium.)
The specific cue point in the time code frame specified in advance (regardless of the reason for specifying it as the cue point) is surely unique in terms of the way the encoded image data is arranged. It can be accessed and played as a point.
The fact that it can be uniquely determined means that even if the cue point is recorded as a pair of the time code of the image and the absolute address on the recorded medium, like the TOC in the CD, the information in the TOC is actually It is guaranteed that there will be no contradiction with the image to be played back.
Therefore, not only the access by the traditional track mechanism but also a more complicated random access mechanism such as PLAYBACKCONTROL, the heading point is handled as a pair of the time code of the image and the absolute address on the recorded medium. The same applies to rules. In the future, it can also be applied to cases where it is necessary to cue interactively, such as video for games.
FIG. 2 shows a so-called two-pass or more system in which encoding is performed N times until optimum encoding can be performed, but the same applies to a so-called one-pass system. In the case of a one-pass system, the quantization level control circuit 15, the quantization level correction device 16, the output rate determination device 18, the storage device 22, and the monitor decoder 21 are unnecessary. This is because the quantization level is fixed in the case of a one-pass system. The output of the entropy encoder 17 is input to the stream output device 19.

It is explanatory drawing of the compression encoding used for description of embodiment. FIG. 1A is an explanatory diagram showing a normal sequence. FIG. 1B is an explanatory diagram showing a cut sequence. [FIG. 1C] It is explanatory drawing which shows an encoder output. [FIG. 1D] It is explanatory drawing which shows a decoder input. FIG. 1E is an explanatory diagram showing a reproduced image. It is a block diagram of the authoring system which shows embodiment. It is explanatory drawing which shows an example of the edit list data and sequence list data shown in FIG. FIG. 3A is an explanatory diagram showing an example of edit list data. FIG. 3B is an explanatory diagram showing an example of sequence list data. It is explanatory drawing which shows an example of a cut sequence. FIG. 4A is an explanatory diagram showing an example of a normal sequence. FIG. 4B is an explanatory diagram showing an example of a cut sequence 0. FIG. 4C is an explanatory diagram showing an example of a cut sequence 1. FIG. 4D is an explanatory diagram showing an example of a cut sequence 2. FIG. 4E is an explanatory diagram showing an example of a cut sequence 3. FIG. 4F is an explanatory diagram showing an example of the cut sequence 4. FIG. 4G is an explanatory diagram showing an example of the cut sequence 5. FIG. 4H is an explanatory diagram showing an example of the cut sequence 6. FIG. 4I is an explanatory diagram showing an example of the cut sequence 7. FIG. 4J is an explanatory diagram showing an example of the cut sequence 8. 3 is a flowchart for explaining main operations of the authoring system shown in FIG. 2. 3 is a flowchart for explaining main operations of the authoring system shown in FIG. 2. 3 is a flowchart for explaining main operations of the authoring system shown in FIG. 2. It is explanatory drawing for demonstrating that GOP with which description of a prior art is provided is not completely independent. It is explanatory drawing for demonstrating the problem in the cue reproduction | regeneration used for description of the prior art. It is explanatory drawing for demonstrating the method of applying CLOSED GOP.

Explanation of symbols

1 Master tape (video tape cassette)
2 Digital VTR
DESCRIPTION OF SYMBOLS 3 Image delay apparatus 4 Operation part 5 Image type control part 6 Flexible disk 7 Cue point reading part 8 Cue point correction apparatus 9 Cut determination circuit 9a ROM
Sd Sequence data 9b RAM
EDLd EDL data SLd Sequence list data 10 DCT
11 Quantizer 12 Inverse Quantizer 13 Inverse DCT
DESCRIPTION OF SYMBOLS 15 Quantization level control circuit 16 Quantization level correction apparatus 17 Entropy encoder 18 Output rate determination apparatus 19 Stream output apparatus 20 Output terminal 21 Monitor decoder 22 Storage apparatus 23 Encoder control part

Claims (16)

In an authoring system that generates encoded data by encoding a video signal,
When a cue point at the time of reproducing the video signal is designated, a delimiter determination that determines a delimiter of the new GOP so that the picture corresponding to the cue point becomes the head of the new GOP in the display order Means,
The picture type of the picture in the new GOP is determined so that reference prediction accompanying encoding is not required between the new GOPs determined by the delimiter determining means,
GOP composing means constituting the new GOP;
Generated bit amount calculating means for calculating a generated bit amount accompanying encoding by encoding the video signal in which the new GOP is configured by the GOP configuring unit ;
Quantization level control means for adjusting a quantization level based on the generated bit quantity calculated by the generated bit quantity calculation means;
Encoding means for generating the encoded data by encoding the video signal in which the new GOP is configured according to the quantization level adjusted by the quantization level control means ;
Authoring system with. 2. The authoring system according to claim 1, wherein the quantization level control unit adjusts a quantization level of a designated cut in the video signal in which the new GOP is configured . Encoding control means for controlling the encoding means to encode only the cut
The authoring system according to claim 2 , further comprising: The GOP composing means composes the cut sequence so that the picture corresponding to the cue point is an I picture, and the last picture in the display order in the GOP immediately before the delimiter is a P picture. The authoring system according to claim 1, comprising a new GOP . 2. The authoring system according to claim 1, wherein the delimiter determining unit determines a break between reproduction units in a logical format of a recording medium or reproduction units in a physical format of a recording medium as a delimiter of the GOP. The authoring system according to claim 1, further comprising recording means for recording the encoded data generated by the encoding means on a recording medium. The authoring system according to claim 1, further comprising output means for outputting the encoded data generated by the encoding means. In an authoring method for generating encoded data by encoding a video signal,
When a cue point at the time of reproducing the video signal is designated, a delimiter determination that determines a delimiter of the new GOP so that the picture corresponding to the cue point becomes the head of the new GOP in the display order Process,
To not require reference prediction associated with coding between the new GOP determined by the delimiter determining step determines a picture type of picture in the new in GOP,
A GOP configuration process for configuring the new GOP;
A generated bit amount calculating step of calculating a generated bit amount accompanying encoding by encoding the video signal in which the new GOP is configured by the GOP configuring step ;
A quantization level control step of adjusting a quantization level based on the generated bit amount calculated by the generated bit amount calculation step;
An encoding step of generating the encoded data by encoding the video signal in which the new GOP is configured according to the quantization level adjusted by the quantization level control step ;
Authoring method including. In an authoring system that generates encoded data by encoding a video signal,
When a cut is designated at a predetermined position of the video signal, delimiter determining means for determining a delimiter of the new GOP so that a picture corresponding to the cut becomes the head of the new GOP in the display order;
The picture type of the picture in the new GOP is determined so that reference prediction accompanying encoding is not required between the new GOPs determined by the delimiter determining means,
GOP composing means constituting the new GOP;
Generated bit amount calculating means for calculating a generated bit amount accompanying encoding by encoding the video signal in which the new GOP is configured by the GOP configuring unit ;
Quantization level control means for adjusting a quantization level based on the generated bit quantity calculated by the generated bit quantity calculation means;
Encoding means for generating the encoded data by encoding the video signal in which the new GOP is configured according to the quantization level adjusted by the quantization level control means ;
Authoring system with. The authoring system according to claim 9, wherein the quantization level control means adjusts a quantization level of a designated cut in the video signal in which the new GOP is configured . Encoding control means for controlling the encoding means to encode only the cut
The authoring system according to claim 10 , further comprising: The GOP composing means composes the cut sequence so that the picture corresponding to the cut becomes an I picture, and the new picture so that the last picture viewed in the display order in the GOP immediately before the delimiter becomes a P picture. The authoring system according to claim 9 constituting a GOP . The authoring system according to claim 9, wherein the delimiter determining means determines a break between reproduction units in a logical format of a recording medium or reproduction units in a physical format of a recording medium as a delimiter of the GOP. The authoring system according to claim 9, further comprising recording means for recording the encoded data generated by the encoding means on a recording medium. The authoring system according to claim 9, further comprising output means for outputting the encoded data generated by the encoding means. In an authoring method for generating encoded data by encoding a video signal,
When a cut is designated at a predetermined position of the video signal, a delimiter determining step for determining a delimiter of the new GOP so that a picture corresponding to the cut becomes a head of the new GOP in the display order;
To not require reference prediction associated with coding between the new GOP determined by the delimiter determining step determines a picture type of picture in the new in GOP,
A GOP configuration process for configuring the new GOP;
A generated bit amount calculating step of calculating a generated bit amount accompanying encoding by encoding the video signal in which the new GOP is configured by the GOP configuring step ;
A quantization level control step of adjusting a quantization level based on the generated bit amount calculated by the generated bit amount calculation step;
An encoding step of generating the encoded data by encoding the video signal in which the new GOP is configured according to the quantization level adjusted by the quantization level control step ;
Authoring method including.

Images