JP2007528568A - Information recording medium on which multi-angle data is recorded, its recording method and reproducing apparatus - Google Patents

Abstract

Provided are an information recording medium on which multi-angle data is recorded, a recording method thereof, and a reproducing apparatus. In an information recording medium on which multi-angle data including at least one angle data is recorded, each angle data is composed of an interleaved block including at least one packet of a predetermined size, and other angle data and an interleaved block. The information recording medium is interleaved with each other, and the interleaved block has an integral multiple of an aligned unit composed of an integer number of packets. Since a plurality of angle turning points recorded on the information recording medium are calculated, the jump distance required by the data during playback does not exceed the maximum jump distance of the playback device. As a result, multi-angle data can be configured efficiently so as to ensure seamless reproduction and reduce the number of jumps during reproduction.

Description

  The present invention relates to multi-angle data used at the time of encoding and decoding moving image data. In particular, the present invention relates to an information recording medium storing multi-angle data, a method for recording and / or reproducing multi-angle data, and multi-angle data. The present invention relates to an apparatus for recording and / or reproducing.

  Multi-angle data refers to data obtained by shooting and encoding a scene at various angles. When attempting to change to a screen shot at another angle during the playback of content containing such multi-angle data, the angle change command is transmitted to the playback device, and the playback device receives the command and receives another command. Play angle data. For this purpose, each angle data is recorded in an interleaving method that is divided into a certain size and is recorded alternately with other angle data.

  Therefore, to read the interleaved block for one angle while reading the interleaved recorded multi-angle data, or to switch to another angle, jump each time you read the interleaved block. I have to. However, if the interleaved block is large, the distance that must be jumped when changing the angle is long and seamless playback is not possible. Therefore, the size of the interleaved block must be determined appropriately.

  And even in one interleaved block, jump points that can jump to interleaved blocks of other angles are placed, but in this case as well, multi-angle data can be efficiently configured only by setting the number of jump points appropriately it can.

  The problems to be solved by the present invention include an information recording medium on which multi-angle data is recorded so that multi-angle data is seamlessly reproduced, a method for recording and / or reproducing multi-angle data, and multi-angle data. An object of the present invention is to provide an apparatus for recording and / or reproducing.

  Another problem to be solved by the present invention is to provide a method for determining the number of angle turning points at which playback positions can be jumped within one interleaved block.

  According to the present invention, in the information recording medium on which multi-angle data including at least one angle data is recorded, each angle data is configured by an interleaved block including at least one packet having a predetermined size. The one angle data is interleaved with at least one other angle data in an interleaved block unit, and the interleaved block is an integer of an aligned unit composed of an integer number of the packets. This is achieved by an information recording medium characterized by having a double size.

  The interleaved block has at least one angle turning point that is a point at which jumping can be continued during reproduction of one angle data, and the angle turning point included in the one interleaved block. Is determined by an integral multiple of the aligned unit.

  In addition, the above-described problem is a method for recording multi-angle data composed of interleaved blocks having at least one angle turning point capable of jumping to a reproduction position by an interleaving method. A step of calculating a distance; a step of correcting the calculated distance value according to a length at which a packet constituting the interleaved block is reproduced at a predetermined time; and a reproduction of a longest jump distance occurring at a jump of a reproduction position Calculating the maximum number of angle turning points in one interleaved unit within the maximum jump distance given to the device, and by calculating the distance between the angle turning points and the number of angle turning points Configure interleaved blocks to Also achieved by a recording method of the multi-angle data, characterized in that it comprises a step of recording.

  On the other hand, according to another field of the present invention, the above problem is at least in an apparatus for reproducing multi-angle data stored in an interleaved block having at least one angle turning point at which a reproduction position can be jumped. A reading unit that reads multi-angle data including one angle data; and a buffer that stores the read data. Each angle data is composed of an interleaved block including at least one packet having a predetermined size. The interleaved block is interleaved with other angle data in units of interleaved blocks, and the interleaved block has a size that is an integral multiple of an aligned unit composed of an integer number of the packets. Also achieved with playback equipment It is.

  According to the present invention, multi-angle data can be efficiently configured so as to ensure seamless reproduction and reduce the number of jumps during reproduction.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  1A to 1C are diagrams illustrating that multi-angle data is interleaved. The multi-angle data is composed of a first angle data file 110 shown in FIG. 1A and a second angle data file 120 shown in FIG. 1B. The file includes audio / video (AV) data for each angle. As shown in FIG. 1C, the first angle data file 110 and the second angle data file 120 are alternately arranged in a continuous area of the recording medium to respond more quickly when the user tries to change the angle view. (130). That is, each angle data file 110, 120 is divided into a certain size and interleaved and recorded. Thereby, when the angle view is changed, the pickup device does not need to move much in order to read the changed angle data, and seamless reproduction is guaranteed.

  Thus, a predetermined unit of angle data included in interleaved data recorded on a recording medium is called an extent. The extent is an interleaved unit in DVD-video. That is, the extent refers to data continuously recorded on the file system. Therefore, the playback device needs to jump between extents in order to read the correct data for playback.

  FIG. 2 is a diagram showing that the interleaved data of FIGS. 1A to 1C is recorded on the recording medium 200.

  An AV stream means a bit stream composed of a plurality of source packets. The source packet is composed of 192 bytes including a 188-byte MPEG-2 TS (transport stream) packet with a 4-byte header. In general, the information recording medium stores data in units of sectors. The sector is a basic unit of file recording, and is composed of 2048 bytes in the DVD. Therefore, one sector is composed of a plurality of source packets.

  FIG. 3 is a simplified block diagram of a playback apparatus for seamless playback. As shown in FIG. 3, the data recorded on the recording medium is read by the reading unit 310 and transmitted to the read buffer 330 via the demodulation unit 320. The read buffer 330 is used to buffer the bit stream transmitted to the decoder in order to ensure seamless playback of moving images even during the time when the pickup device 305 of the reading unit 310 jumps. The source depacketizer 340 converts a bit stream including a plurality of source packets into MPEG-2 TS packets and outputs MPEG-2 TS packets.

  The parameters related to buffering are defined as follows.

(A) R _UD : Data rate of data transmitted from the reading unit 310 to the read buffer 330 via the demodulation unit 320.

(B) R _TS : Maximum value of TS_recording_rate which is the encoding rate of MPEG-2 TS (output speed of data output to the decoder).

(C) R _MAX : Maximum bit rate of the source packet stream. The MPEG-2 TS packet is composed of 188 bytes, and a 4-byte header is added thereto to generate a source packet stream. Therefore, R _MAX is (192/188) × R _TS .

When data from the read buffer 330 is output to the decoder at a rate of TS_recoding_rate, stored data _{B OCCUPIED} stored in the read buffer 330 to satisfy the following equation _(1), the data in the read buffer 330 to the _{T JUMP} time Even if it is not performed, an underflow of the read buffer 330 does not occur.

図４は、ピックアップ装置３０５がジャンプする間に、リードバッファ３３０に保存されたデータの量を示すグラフである。図４において、Ｔ_ＪＵＭＰは、ジャンプ時間（アクセス時間Ｔ_{ＡＣＣＥＳＳ}及び二つのＥＣＣ（Ｅｒｒｏｒ Ｃｏｒｒｅｃｔｉｎｇ Ｃｏｄｅ）ブロックを読み取る時間Ｔ_{ＯＶＥＲＨＥＡＤ}）である。すなわち、Ｔ_ＪＵＭＰ＝Ｔ_{ＡＣＣＥＳＳ}＋Ｔ_{ＯＶＥＲＨＥＡＤ}であり、Ｔ_{ＯＶＥＲＨＥＡＤ}［ｍｓ］≦（２×Ｅｃｃ［ｂｙｔｅ］／Ｒ_ＵＤ）［ｂｐｓ］である。

FIG. 4 is a graph showing the amount of data stored in the read buffer 330 while the pickup device 305 jumps. In FIG. 4, T _JUMP is the jump time (access time T _ACCESS and time T _OVERHEAD for reading two ECC (Error Correcting Code) blocks). That is, T _JUMP = T _ACCESS + T _OVERHEAD and T _OVERHEAD [ms] ≦ (2 × Ecc [bytes] / R _UD ) [bps].

When the data recorded on the information recording medium is read, the read buffer is gradually filled, and when the read buffer 230 is filled as defined above before the pickup device jumps to a new position, the read buffer underflow is read. There is no flow. Therefore, in order to prevent underflow of the read buffer, the length S _{READ of} data read into the read buffer before the jump must satisfy the following equation (2).

図５は、マルチアングルのためにインターリービングされているクリップファイルの構造を示す図である。

FIG. 5 is a diagram illustrating a structure of a clip file interleaved for multi-angle.

As described above, each angle data is interleaved with other angle data in order to perform a seamless angle change by shortening the jump time and the response time for the angle change. Accordingly, not only at the time of changing the angle, but also at the time of general reproduction, the jump is searched and the corresponding angle data is searched and reproduced. An interleaved block can be said to be one extent in a clip file. One extent can include a plurality of angle turning points that can jump to other angle data. As a result, the length S _{EXTENT of the} extent and the distance S _{ANGLE_POINTS} between the two angle turning points must satisfy the following equation (3).

図５のマルチアングルのためのクリップファイルは、次のような制約条件を有している。第１に、クリップファイルは、一つのレイヤ上に位置せねばならない。第２に、それぞれのマルチアングルストリームのエクステントは、アングルポイントで始まり、アラインドユニットにより整列されている。もし、最後のアラインドユニットが入力されたトランスポートストリームで完全に充填されなければ、残りの空間はＮＵＬＬパケットで充填される。第３に、Ｓ_{ＡＮＧＬＥ＿ＰＯＩＮＴＳ}は、ソースパケットの長さ（１９２バイト）の整数倍である。第４に、エクステントの長さＳ_{ＥＸＴＥＮＴ}、Ｓ_{ＥＸＴＥＮＴ}でのアングル転換点の数、アングル転換時間は、前述したバッファ条件を満足せねばならず、幾つかの場合に、バッファと関連したパラメータ値の例を挙げれば、後述する表１及び表２に示したようである。

The clip file for multi-angle in FIG. 5 has the following constraint conditions. First, the clip file must be located on one layer. Second, each multi-angle stream extent starts at an angle point and is aligned by an aligned unit. If the last aligned unit is not completely filled with the incoming transport stream, the remaining space is filled with NULL packets. Third, S _{ANGLE_POINTS} is an integer multiple of the length of the source packet (192 bytes). Fourth, the length of the extent S _EXTENT , the number of angle turning points in S _EXTENT and the angle turning time must satisfy the buffer conditions described above, and in some cases, the parameter value associated with the buffer. For example, it is as shown in Table 1 and Table 2 described later.

On the other hand, S _{ANGLE_POINTS} is shorter than S _EXTENT , and the largest value of T _ACCESS at the time of angle change _jumps from the current angle turning point in the current angle data unit to the farthest angle turning point in the next angle data unit. It will be the jump time. The angle data unit represents a plurality of data blocks corresponding to the same time, and each block corresponds to each angle data. As shown in FIG. 5, angle 1-1, angle 2-1 and angle 3-1 are regarded as the current angle data unit, and angle 1-2, angle 2-2 and angle 3-2 are the next angle data. Considered a unit. The largest value of _TACCESS is converted to angle 3 before reproducing the data of angle 1-1 and passing through the third angle turning point 510 of the angle 1-1 data and before passing through the last angle turning point 520. If the command is received, it is necessary to jump to the first angle turning point 530 of the angle 3-1 data, and in this case, T _ACCESS is the largest value.

If there are a plurality of angle turning points in one extent, S _{READ in} FIG. 4 becomes S _{ANGLE_POINTS} . Therefore, equation (2) can be expressed as:

さて、与えられた接近時間、最大のジャンプ距離及びＴＳ＿ｒｅｃｏｒｄｉｎｇ＿ｒａｔｅを有する一つのエクステント内に、幾つかのアングル転換点を有するかを計算する方法について説明する。与えられたパラメータを有し、各Ｓ_{ＡＮＧＬＥ＿ＰＯＩＮＴＳ}及びＳ_{ＥＸＴＥＮＴ}を求めるための最初の方法は、次の通りである。

Now, a method for calculating how many angle turning points are included in one extent having a given approach time, maximum jump distance, and TS_recording_rate will be described. The first method for determining each S _{ANGLE_POINTS} and S _EXTENT with given parameters is as follows.

FIG. 6 is a flowchart of a method for calculating S _{ANGLE_POINTS} and S _EXTENT .

_{SANGLE_POINTS} is calculated using Equation (3) with the given T _ACCESS and TS_recording_rate (S610). Then, the data length A when the data of the given TS_recording_rate is reproduced during 500 ms and the data length B when reproduced during 1000 ms are calculated (S620). This is because, in MPEG-2, the GOP (Group of Picture) interval is about 500 ms to 1000 ms, so it is meaningless to set the angle turning point in a time shorter than 500 ms. Then, the obtained S _{ANGLE_POINTS} is compared with the A value and the B value, and if S _{ANGLE_POINTS} ≦ A, S _{ANGLE_POINTS} = A, and if A <S _{ANGLE_POINTS} ≦ B, S _{ANGLE_POINTS} = B is determined (S630). .

A maximum M (the number of angle points in one interleaved unit) that satisfies “the longest jump distance <the maximum jump distance in a given T _ACCESS ” is searched (S640). The maximum jump distance provided by the playback device is already given, and the longest jump distance is 2 × (number of angles−1) × M × _{SANGLE_POINTS,} and M is calculated using this. To do. Thus, S _EXTENT = INT [(M × S _{ANGLE_POINTS} + 6144−192) / 6144] × 3, and has M angle points.

  Considering a jump between two angle turning points, the angle unit (data between two angle points within one angle data) itself is preferably aligned by a sector.

Tables 1 and 2 show examples of S _EXTENT and S _{ANGLE_POINTS} calculated in this way. Table 1 shows S _EXTENT and S _{ANGLE_POINTS} when there are 3 angles, and Table 2 shows when there are 9 angles.

一般的に、ファイルのエクステントはセクタにより整列される。本発明において、ソースパケットは１９２バイトであるため、２０４８バイトであるセクタ単位で整列されない。したがって、三つの連続されたセクタを合わせてアクセスユニットで定義する。三つのセクタは、整数倍のソースパケットを備える最小限のセクタ数である。すなわち、一つのセクタが２０４８バイトである場合、３２個のソースパケットの長さは、三つのセクタ、すなわち一つのアクセスユニットの長さと同一である。

Generally, file extents are aligned by sector. In the present invention, since the source packet is 192 bytes, it is not arranged in units of sectors of 2048 bytes. Therefore, three consecutive sectors are combined and defined in the access unit. Three sectors are the minimum number of sectors with an integer number of source packets. That is, when one sector is 2048 bytes, the length of 32 source packets is the same as the length of three sectors, ie, one access unit.

  On the other hand, the above-described multi-angle data recording method can be created by a computer program. Codes and code segments constituting the program can be easily inferred by computer programmers in the field. The program is stored in a computer-readable information recording medium, and is read and executed by the computer, thereby realizing a multi-angle data recording method. The information recording medium includes a magnetic recording medium, an optical recording medium, and a carrier wave medium.

It is a figure which shows a 1st angle data file. It is a figure which shows a 2nd angle data file. It is a figure which shows the case where 1st angle data and 2nd angle data are interleaved and preserve | saved. It is a figure which shows that the said interleaved data is recorded on the recording medium. It is a partial block diagram of the reproducing | regenerating apparatus for seamless reproduction | regeneration. 6 is a graph showing the amount of data stored in the read buffer while the pickup device jumps. It is a figure which shows the structure of the clip file interleaved for multi angles. ₅ is a flowchart of a method for calculating S _{ANGLE_POINTS} and S _EXTENT .

Claims (18)

In an information recording medium on which multi-angle data including at least one angle data is recorded,
The angle data unit is composed of a plurality of blocks, and each block includes at least one packet of a predetermined size and corresponds to each angle data.
The blocks are interleaved with each other;
The information recording medium, wherein the interleaved block has a size that is an integral multiple of an aligned unit composed of an integer number of the packets.   The interleaved block has at least one angle turning point that is a point at which the playback apparatus can jump and continue playback during playback of the multi-angle data, and is included in the one interleaved block. 2. The information recording medium according to claim 1, wherein the number of angle turning points is determined by an integral multiple of the aligned units in each interleaved block.   The information recording medium according to claim 1, wherein the packet of the predetermined size is configured by 192 bytes and includes a header and an MPEG-2 transport stream. In a method for recording multi-angle data composed of interleaved blocks having at least one angle turning point at which a playback device can jump to a playback position during data playback,
Calculating a distance between the angle turning points;
Correcting the calculated distance value according to a length by which packets constituting the interleaved block are reproduced at a predetermined time;
The longest jump distance that the multi-angle data can acquire during data playback is shorter than or equal to the maximum jump distance of the playback device, and the maximum number of angle turning points in one interleaved block is set. A calculating step;
A method of recording multi-angle data, comprising: forming an interleaved block and recording multi-angle data according to the calculated distance between angle change points and the number of angle change points. Calculating the distance between the angle turning points;
5. The multi-angle data recording method according to claim 4, further comprising a step of calculating a distance between the angle change points based on an access time of the reproducing apparatus and a recording bit rate of the data stream. The step of correcting the calculated distance value according to the length at which packets constituting the interleaved block are reproduced at a predetermined time,
Calculating a data length at which the data stream is reproduced at a first designated time and a data length reproduced at a second designated time longer than the first designated time;
When the distance between the angle change points is shorter than the data length reproduced at the first designated time, the distance between the angle change points is corrected to the data length reproduced at the first designated time. When,
When the distance between the angle turning points is longer than the data length reproduced at the first designated time and shorter than the data length reproduced at the second designated time, the distance between the angle turning points is 6. The multi-angle data recording method according to claim 5, further comprising a step of correcting the data length to be reproduced at the second designated time. Calculating the maximum number of angle turning points in the one interleaved unit,
Calculating 2 × (number of angles−1) × M × S _{ANGLE_POINTS} as the longest jump distance;
5. The method of recording multi-angle data according to claim 4, further comprising the step of calculating a maximum number M of angle turning points using the longest jump distance. According to the calculated distance between the angle turning points and the number of angle turning points, the step of configuring the interleaved block and recording the multi-angle data includes:
Calculating a size of an interleaved block using the calculated distance between the angle turning points and the number of angle turning points;
Adjusting the size of the interleaved block to be an integer multiple of an aligned unit composed of an integer number of packets of a predetermined size;
The multi-angle data recording method according to claim 6, further comprising a step of recording the multi-angle data in the interleaved block.   9. The multi-angle data recording method according to claim 8, wherein the packet having a predetermined size is composed of 192 bytes and includes a header and an MPEG-2 transport stream. In a multi-angle data playback device capable of playing back angle data selected from multi-angle data during data playback,
A reading unit for reading multi-angle data;
A buffer for storing the read multi-angle data,
The multi-angle data is composed of a plurality of blocks, and each block includes at least one packet of a predetermined size,
The blocks are interleaved with each other;
The playback apparatus according to claim 1, wherein the interleaved block has a size that is an integral multiple of an aligned unit composed of an integer number of the packets.   The interleaved block has at least one angle turning point that is a point at which jumping can be continued during reproduction of one angle data, and the angle turning point included in the one interleaved block. The reproduction apparatus according to claim 10, wherein the number of is determined by an integral multiple of the aligned unit. In a method for saving data to play a screen from a plurality of different angles,
Obtaining data corresponding to the screen from the plurality of angles;
Storing the data in a recording medium in an interleaved block,
The data of each block is selectively selected from data for reproducing the screen from each angle, and data stored in one of the plurality of blocks by the playback device to data stored in another block. It has data for multiple angle turning points that determine the points to instruct to jump,
Each angle turning point is aligned with the start point of each sector of the recording medium,
The storage method according to claim 1, wherein the data of each block includes a plurality of data packets having the same amount as an integral multiple of a recording capacity of one sector of the recording medium.   13. The storage method according to claim 12, further comprising a step of determining a data length of each block based on the number of the plurality of angles and an expected value of the maximum jump time of the playback device.   13. The method of claim 12, further comprising: calculating a maximum number of the angle change points based on an estimated value of a maximum jump time of the playback device, a data length of each block, and the number of the plurality of angles. The storage method described in 1. In an information recording medium in which data for reproducing one screen from a plurality of angles is provided with angle data of a plurality of units,
Each angle data unit includes a plurality of blocks, each block includes a plurality of source packets, and corresponds to one angle and the same time frame among the plurality of angles,
The blocks are interleaved with each other;
The interleaved block comprises an integer number of sectors of the recording medium,
The length of the integer number of sectors is the same as the length of the integer number of source packets provided in each block;
The angle recording unit is an information recording medium, wherein the angle data units are interleaved with each other. In the method of playing multi-angle data,
Reading multi-angle data composed of a plurality of blocks from one of a recording medium and a data stream;
Buffering the read multi-angle data;
Depacketizing the packet of buffered data according to a selected angle and converting the buffered data into a packet stream that can be seamlessly reproduced, and
Each block includes at least one packet having a predetermined size, the blocks are interleaved with each other, and the interleaved block is an integral multiple of an aligned unit composed of an integer number of the packets. A reproduction method characterized by comprising: Each interleaved block includes the same number of angle turning points as an integer multiple of the integer number of aligned units;
The method includes the step of continuing to play back the selected angle data while jumping from the angle turning point of the block having the selected angle data to the angle turning point of the block having the other angle data selected. The reproduction method according to claim 16, further comprising:   The buffering step may be configured such that the data rate of the read angle data, the rate of converting the buffered data into the reproducible packet data stream, and the recording medium and the data stream from the multi 17. The reproducing method according to claim 16, further comprising the step of buffering a corresponding amount of data based on a maximum delay time for obtaining angle data.

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