JP2002313065A - Player - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a player capable of precisely carrying out searching reproduction without mistakes with time designation concerning the reproduction of block data subjected to editing for designating a section skip from a recording medium. SOLUTION: In the case of providing a skipping period to an information recording medium having at least one time recording position collation table consisting of at least one piece of collation data and time correction data of each fixed time interval in a recording area different from the recording area of the block data, the read time recording position collation table is divided corresponding to a designated skip period, collation data indicating the block data of the designated skip period is deleted, second time correction data is calculated corresponding to the skip period, a new time recording position collation table is prepared by combining collation data after the deleted collation data and written back in the recording medium with the time recording position collation table hourly preceding the deleted data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a reproducing apparatus, and more particularly to a reproducing apparatus for reproducing edited block data from a recording medium.

[0002]

2. Description of the Related Art Recent advances in information processing technology have
2. Description of the Related Art It has been widely practiced to compress digital audiovisual information and record it on an information recording medium. Especially for video information, the amount of information is enormous, and advanced compression techniques are used in order to effectively use the limited amount of information recorded on the information recording medium. A typical example of this advanced compression technique is not only data compression using correlation within a frame that is a unit of video, but also compression using correlation between a plurality of temporally adjacent frames. Today, it is widely used for recording and transmitting video information.

[0003] When editing the result of data compression, if frame correlation is used, deletion in frame units becomes impossible. This is because the reference source frame cannot be decoded if there is no reference destination frame to be correlated. Therefore, in many cases, a plurality of frames are divided into blocks in preparation for subsequent editing, and encoding is performed so that blocks can be handled independently without performing frame correlation processing between blocks. It is well known that the block data coded in block units have different data capacities depending on the complexity of the video in the block and the degree of correlation between frames.

Now, these block data are recorded on the information recording medium, but the block data is arranged from the head of the sector so as to occupy an integer number of sectors, and the reproduction operation is taken into consideration in reproducing. There is a need. Therefore, a measure is taken by performing encoding including embedded data at the end of block data by a known method.
Thus, the block data is recorded in the information area A shown in FIG.

In order to efficiently compress video information, the video information is often divided into blocks each having a different number of frames. That is, it is necessary to consider that the display periods of the respective blocks shown in FIG. 7 are different from each other on a frame period basis. Furthermore, since the compression rates per block are different from each other, the capacities of the block data are different from each other as shown in FIG.

[0006] The above situation is described by linear pulse code modulation (PC
M) and the like, it is very difficult to perform search playback in which time is specified and playback is started from a block data sequence, as compared with a case where the relationship between time lapse and the total amount of encoded data is proportional. It is expected that there is.

In order to solve this problem, conventionally, a time recording position comparison table is separately recorded, and search reproduction is performed using this comparison table. , Apparatus and medium reproducing apparatus ”). In this medium recording method, video information, which is predetermined main information, is converted into an MPEG (Motion Picture), which is an international standard for moving images.
A method of generating a plurality of GOPs (Groups of Pictures), which are compression units, by encoding using a ving Picture Experts Group) method and recording the generated plurality of GOPs on a recording medium. Generates a start address of data for each time unit when divided and
It is recorded on a recording medium together with P.

In other words, according to this medium recording method, the time recording position comparison table is composed of a sequence of reproduction start addresses for each predetermined time unit, and coded data is divided into blocks in a compression unit called GOP. G as playback start address
Information indicating the start position of the OP is recorded. FIG. 7 conceptually shows this state.

[0009]

However, in the above-mentioned conventional method, search and reproduction are performed in a situation where the block data string is not updated, for example, in a situation where the block data string is recorded on a read-only medium. However, a problem may occur when the block data sequence is updated. When a block data string is recorded on a rewritable recording medium, its contents can be edited. As an example, as shown in FIG. 8, a reproduction skip instruction in units of block data can be considered. Generally, information specifying a reproduction section and its reproduction order is recorded on a recording medium as reproduction control data, so that it is not always necessary to delete the skipped block data.

When the block indicated by D in FIG. 8 is skipped, the reproduction period s of the block indicated by D becomes zero during reproduction. Also, since the reproduction start address 3 indicates the section to be skipped, it must be deleted from the time recording position comparison table. The period s is the period u
Therefore, all reproduction start addresses after the reproduction start address 4 must be updated to indicate a correct position. For this purpose, it is necessary to recalculate the address information based on the relationship between the block capacity after the block D and the reproduction period, and the editing process may be extremely complicated.

The present invention has been made in view of the above points,
It is an object of the present invention to provide a reproducing apparatus capable of accurately performing search reproduction by time specification without error for reproduction of block data that has been edited to specify section skipping from a recording medium.

[0012]

In order to achieve the above object, a reproducing apparatus of the present invention divides a temporally continuous information signal into blocks of a predetermined time unit and makes the code amount of each block variable. A first recording area in which a plurality of block data after data compression by the encoded data are recorded in time series;
The time correction data and 1 for each fixed time interval u for reproducing the predetermined block data from the first recording area.
A time record position comparison table consisting of one or more control data,
Rewriting having a second recording area in which m pieces of m (m is a natural number) continuous playback sections set by editing the block data recorded in the first recording area are recorded. A possible information recording medium, wherein the n-th (n is a natural number) reference data in each time recording position comparison table is the first block data of one continuous playback section to which each time recording position comparison table corresponds. From the first one of the continuous playback sections being played back at a point in time when (n × u) time (u is the fixed time interval) has elapsed after the playback is started.
, And a set of block data position information based on the start of the recording area and time difference information of the difference between the reproduction start time of the block data indicated by the block data position information and the (n × u) time. The time correction data in the time recording position comparison table is a block to be reproduced when the n-th reference data has been edited and the (n × u) -c time has elapsed from the start of reproduction of the corresponding one continuous reproduction section. In the case where the information indicates data, from the rewritable information recording medium, which is data for correcting the time c, according to the set continuous playback section of the block data recorded in the first recording area. Playback
A playback device that performs playback based on a playback start position that is time-specified from the outside, wherein the read-out is performed based on the time correction data and the time difference information included in the time recording position comparison table read from the second recording area. It is determined at which point in time the respective reference data of the time recording position comparison table is from the beginning of the set continuous playback section corresponding to the read time recording position comparison table, and the data is reproduced from the outside. A reproduction unit for specifying a reproduction start position in the first recording area corresponding to a time specified as a start position, and reproducing the block data from the specified reproduction start position. .

[0013]

Next, embodiments of the present invention will be described with reference to the drawings. First, an embodiment of the information recording medium used in the present invention will be described. FIG. 1 shows the data arrangement of one form of the information recording medium and the data format of the time recording position comparison data. This information recording medium is a rewritable information recording medium divided into sectors of a fixed data amount, which divides time-continuous information into blocks, changes the code amount of each block, and uses an integer number of sectors. As shown by 11 to 11 in FIG. 1, k block data (k is a natural number corresponding to the length of information to be recorded) and block data in the information area A in time series are shown as 11 to 11 in FIG. Has been recorded. The above-mentioned information is, for example, video information and audio information multiplexed by compression encoding in the MPEG system. For example, the block data is configured in GOP units, but the details are not the gist of the present invention. Description is omitted.

In the information area B of the information recording medium different from the information area A, the time recording position reference data 12 is recorded. This time recording position comparison data 12 is
As will be described later, when there are m continuous playback sections in the information area A by editing, the time recording position comparison data 12
Are recorded in the information area B (m = 3 as an example in FIG. 1, and m = 3 in the initial recording before the editing is performed).
1).

The time recording position reference data 12
1 includes time correction data 12a and z (z is a natural number) reference data 12b, as shown in FIG. The time correction data 12a is data for correcting the time c when the n-th control data becomes information at the time when (n × u) -c time has elapsed from the start of reproduction after the editing described later is performed. is there.

Each of the reference data 12b is data for each fixed time interval u, and includes block data position information 13 and time difference information 14. The block data position information 13 of the n-th reference data of each time recording position reference data 12 starts reproduction from the first block data of one continuous reproduction section in the information area A corresponding to the time recording position reference data 12. At the time point when (n × u) time has elapsed. The time difference information 14 includes the reproduction start time of the block data indicated by the block data position information 13 and the above (n × u)
Indicates the time difference from the time. When information is first recorded on the information recording medium (in an initial state before rewriting by editing is performed), a series of block data 11 to 11
Are continuously reproduced, and search reproduction at a designated time is possible using the time recording position reference data 12.

FIG. 2 shows an example of the relationship between block data and reference data during initial recording, which are recorded on the information recording medium. In the figure, the fixed time interval u is "60" (the unit is seconds, but it may be a frame), five control data 1-5 are recorded in the information area B, and the control data 1-5 As the block data position information shown, a relative sector address from the head of the information area A is used, and the block data position information shown by the reference data 1 to 5 is, as shown in FIG. Block data start addresses “120”, “26”
0 "," 360 "," 460 ", and" 620 ".

As a result, in the time recording position comparison data 12 recorded in the information area B at the time of the initial recording, the value of the time correction data 12a is "0" as shown in FIG.
The block data position information 13 is a value of the above-described relative address, and the time difference information 14 is a value shown in FIG. 3 based on FIG. For example, the block data position information 12 of the reference data 4 indicating the block position of the data block shown in FIG.
460 ", and the reproduction start time is earlier by" 20 "than the sum (integrated value) of the fixed time intervals indicated by the reference data 4, as shown in FIG. 2, so that the time difference information 14 is shown in FIG. Thus, it is "20".

The time recording position reference data 12 includes the reference data 12 b, the block position information 13, and the time difference information 1.
4 are associated with each other as a set, and are also referred to as time recording position comparison tables in this specification.

Next, an embodiment of the editing apparatus will be described. FIG. 4 shows a block diagram of one embodiment of the editing apparatus.
As shown in the drawing, the editing apparatus includes an information reading unit 22 that reads (reproduces) a time recording position comparison table from a rewritable recording medium 21 that is the information recording medium described above.
An information memory 23 for temporarily storing the time recording position comparison table read by the information reading unit 22, a skip period instruction unit 24 for specifying a skip period, and reading the time recording position comparison table stored in the information memory 23. A control unit 25 that performs various processes corresponding to the skip period instructed on the time recording position comparison table and writes the information back to the information memory 23, and writes the information written back to the information memory 23 to the rewritable recording medium 21. An information writing unit 26 for writing;
It comprises an information decoding unit 27 and an information display unit 28.

Here, the control unit 25 applies a division process, a comparison data deletion process, a time correction data calculation process, a division process and a division process corresponding to the designated skip period to the time recording position comparison table read from the information memory 23. A plurality of comparison tables are formed by combining the partially deleted comparison data and the time correction data, and processing for writing back to the information memory 23 is executed. Further, the information decoding unit 27 includes the information reading unit 22.
Decrypts the read block data. The information display unit 28 displays the video information decoded by the information decoding unit 27.

Next, a description will be given of the processing relating to the time recording position comparison table by the editing apparatus of FIG. 4 when the skip period instruction section 24 instructs to skip the block data indicated by D in FIG. The information is read from the rewritable recording medium 21 by the information reading unit 22 in FIG.
As shown in FIG. 5A, the time recording position comparison table transferred to the information memory 23 is the same as the time recording position comparison table of the rewritable recording medium 21 at the time of the initial recording shown in FIG.

Next, the skip instruction from the skip period instruction section 24 indicates that the block data indicated by D in FIG. 2 is to be skipped.
5 is performed between the block data indicated by the reference data 3 and the block data indicated by the reference data 3, the control unit 25 sets the skip start timing as a division point between the reference data 2 and the reference data 3 as shown in FIG. To divide.

Subsequently, the control unit 25 deletes the control data 3 indicating the block data (of FIG. 2) to be skipped as shown in FIG. 5 (c). Subsequently, the control unit 25
Calculates time correction data for the period after the skip. This is obtained by integrating the reproduction periods from the block data after skipping to immediately before the block data indicated by the reference data 4 (in FIG. 2), and becomes time correction data = fixed time interval− (integrated value + time difference information of control data 4). It is calculated based on the formula.

In the example of FIG. 2, the control data 4 after the skip
There is one block data indicated by S immediately before the block data indicated by, and "20" which is a reproduction period of the block data S is obtained. The time difference information “20” of the reference data 4 is added to this value, and the value after the addition is subtracted from the fixed time interval u (= 60) to calculate “20” as the time correction data.

Next, the control unit 25 compares the time correction data calculated in this way with the deleted control data which is a control data group corresponding to a continuous reproduction section temporally after the skip period. A second time recording position comparison table is added to the control data 4 and the control data 5, as shown in FIG. 5D. This second time recording position comparison table is written back to the information memory 23 together with the first time recording position comparison table which is a set of the comparison data 1, the comparison data 2 and their time correction data. The time recording position comparison table shown in FIG. 5D written back to the information memory 23 is read by the information writing unit 26 and written into the information area B of the rewritable recording medium 21.

As a result, the details of the recording time recording position comparison table of the rewritable recording medium 21 after writing are shown in FIG. A second time recording position comparison table 32 for data 4 and 5 is provided. That is, one comparison table is prepared for the continuous playback section. After confirming the normal writing back, the time record position comparison table of FIG. 3 before editing may be deleted.

As a result, at the time of reproducing the rewritable recording medium 21, the search operation can be accurately performed in consideration of the fact that the reference data is the information at the time earlier by the time correction data. That is, in the example of FIG. 2, the continuous reproduction section after the skip period starts from the block data S, and the reference data 4 which is the first reference data from the continuous reproduction start position is the original data from the continuous reproduction start position. It is understood that the information is not “60”, but information “40” earlier by “20” of the time correction data in the second time recording position comparison table 32 shown in FIG. The search operation can be performed accurately. Also, in the above formula, the only item that actually needs to be calculated is the integrated value, and this integrated value may be directly used as the time correction data.

[0029]

As described above, according to the present invention,
Even during playback after editing that specifies section skipping, it is possible to use the corrected time data and time difference information to accurately know at which point in time each control data is viewed from the beginning of the continuous playback section, There is no mistake in search playback in.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a data arrangement and a time recording position comparison data format of an embodiment of an information recording medium reproduced by a reproducing apparatus of the present invention.

FIG. 2 is a diagram showing a relationship between a data block at the time of initial recording on an information recording medium reproduced by a reproducing apparatus of the present invention, a designated skip period, and reference data.

FIG. 3 is a diagram illustrating an example of a time recording position comparison table;

FIG. 4 is a block diagram of one embodiment of an editing device.

5 is an explanatory diagram of processing of a time recording position comparison table by the editing device in FIG. 4;

FIG. 6 is an explanatory diagram of a time recording position comparison table after editing by the editing device of FIG. 4;

FIG. 7 is a diagram showing an arrangement of block data and a reproduction period.

FIG. 8 is an explanatory diagram of skip reproduction of block data.

[Explanation of symbols]

11 1 to 11 k Block data 12 Time recording position reference data 12a Time correction data 12b Reference data 13 Block data position information 14 Time difference information 21 Rewritable recording medium 22 Information reading unit (Reading unit) 23 Information memory (Memory unit) 24 Skip period instruction Unit (skip period instructing unit) 25 control unit (dividing unit, deleting unit, calculating unit, writing back unit) 26 information writing unit (writing unit) 27 information decoding unit 28 information display unit

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 5/91 H04N 5/92 H 5/92 G11B 27/02 B (72) Inventor Takayuki Sugawara Yokohama, Kanagawa 3-12 Moriyacho, Kanagawa-ku, Japan F-term (reference) in Victor Company of Japan, Ltd. DC26

Claims (1)

[Claims] An information signal which is continuous in time is divided into blocks of a predetermined time unit, and a plurality of block data after data compression by encoding with a variable code amount for each block are recorded in time series. A time recording position comparison table including a first recording area and time correction data for reproducing the block data from the first recording area and one or more pieces of reference data for each fixed time interval u. And a second recording area in which m pieces are recorded corresponding to m (m is a natural number) continuous playback sections set by editing the block data recorded in the first recording area. A rewritable information recording medium, wherein the n-th (n is a natural number) reference data in each of the time recording position comparison tables is one continuous reproduction section corresponding to each of the time recording position comparison tables. , Indicating the block data in the corresponding one continuous playback section being played back at the point of time when (n × u) time (u is the fixed time interval) has elapsed after the start of playback from the first block data of 1 is a set of block data position information based on the beginning of the recording area, and time difference information of a difference between the reproduction start time of the block data indicated by the block data position information and the (n × u) time. The time correction data in each time recording position comparison table is reproduced when the n-th reference data has passed (n × u) -c time from the start of reproduction of the corresponding one continuous reproduction section by editing. When the information indicates block data, the block recorded on the first recording area from a rewritable information recording medium that is data for correcting the time c is used. A playback device that plays back the set data in accordance with the set continuous playback section based on an externally designated playback start position, wherein the playback device has the time recording position comparison table read from the second recording area. Based on the time correction data and the time difference information, each reference data included in the read time recording position comparison table is viewed from the top of the set continuous playback section corresponding to the read time recording position comparison table. It is determined at what point in time the data is, and a reproduction start position in the first recording area corresponding to a time designated as a reproduction start position from the outside is specified. A reproducing apparatus comprising reproducing means for reproducing data.