JPH07143437A - Video signal reproduction device - Google Patents

Abstract

PURPOSE:To attain the special reproduction such as slow reproduction or high speed reproduction by correcting data acceptable by a decoder even when missing or duplication of data take place. CONSTITUTION:A coded data separator 3 detects and separates auxiliary data such as various headers from stored coded data. First coded data are stored in a buffer memory 4, and 2nd coded data (for auxiliary data) are stored in a buffer memory 5. A coded position information detector 6 reads coded position information representing which part of coded data of each macro block in 1st coded data is coded from a header at a corresponding position in 2nd coded data. A coding position information comparator 7 compares coded position information set in each macro block to check duplicated data. A duplicate data elimination device 8 eliminates duplicated data from the 1st and 2nd coded data based on duplicate information of the coding position information comparator 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video signal reproducing apparatus for reproducing coded data obtained by high efficiency coding a video signal.

[0002]

2. Description of the Related Art In recent years, ISO / IEC SC29 / WG
The so-called MPEG (Moving Picture E) being studied in
xpert Group) has attracted attention, and as a device for recording / reproducing the encoded data encoded by this encoding method, the encoded data is stored in a predetermined order in the order in which it is sent from the encoder. It is common to packetize and record each bit number, concatenate the read packets at the time of reproduction to restore the original data, and send it to the decoder.

FIG. 4 shows the structure of a conventional reproducing apparatus. In the figure, 1 is an error correction encoder, 2 is a buffer memory, and 9 is a data rearranger. The operation of the playback device is shown below.

The encoded data input from the recording medium is
The error correction code is removed by the error correction encoder 1 and stored in the buffer memory 2 for a predetermined m frames. The encoded data is rearranged by the data rearranger 9 in the order received by the decoder and is output. The output encoded data is decoded and reproduced as an image signal by a decoder connected to the outside.

[0005]

However, the conventional configuration has a drawback that special reproduction cannot be sufficiently performed. In other words, if the structure is such that data loss occurs during high-speed playback and data duplication occurs during slow playback, and the decoder has a structure that does not allow data loss or duplication, the images during slow and high-speed playback are restored. It is impossible to do. Also, data duplication may occur not only during slow playback, but also due to the data placement method on the track, such as double writing of data and special placement of data that extracts important parts, and the head locus during playback. There is. On the other hand,
The decoder meets the standard for normal playback and enables decoding playback, but the behavior when special data reproduction or data loss or duplication occurs depends on each decoder, and in the worst case no image is displayed. It can happen.

In view of the above point, the present invention provides a video signal reproducing apparatus capable of performing special reproduction such as slow reproduction and high-speed reproduction by correcting the data to be accepted by the decoder even when the above-mentioned data omission or duplication occurs. The purpose is to get.

[0007]

According to a first aspect of the present invention, a storage means for storing coded data acquired from a recording medium within a predetermined time and a coded video signal for each part of the coded data. And a coding position information detecting means for obtaining coding position information which is information indicating a screen number and a position occupied on the screen, and coding position information of each part of the coded data as the remaining part of the coded data. The encoded position information comparing means for comparing with the encoded position information of, and the result of the comparison,
The remaining part is classified into a first data part having coded data occupying the same position on the screen, and a second data part having no coded data occupying the same position on the screen in the remaining part. The duplication part classification means, the data deletion means for deleting a part of the coded data so that duplications occupying the same position on the screen in the data belonging to the first data part are eliminated, and the data deletion means And a data rearranging means for rearranging the encoded data after the deletion of the data in the order received by the decoding unit.

According to a second aspect of the present invention, a storage means for storing the encoded data acquired from the recording medium within a predetermined time, a screen number on the encoded video signal, and a screen for each part of the encoded data. Coded position information detection means for obtaining coded position information which is information indicating a position occupied above, and among each position on the screen, included in any of the positions occupied on the screen in all parts of the coded data. An unprocessed position detecting means for detecting an unprocessed position which is a non-processed position, an encoded data generating means for generating encoded data for decoding the unprocessed position and adding the encoded data to the encoded data, and the encoding And a data rearrangement unit that rearranges the encoded data added with the data by the data generation unit in an order in which the decoding unit receives the encoded data.

According to a third aspect of the present invention, storage means for storing the coded data acquired from the recording medium within a predetermined time period, and the first coded data which is data obtained by coding the accumulated data. Coded data classification means for classifying into the second coded data, which is the coded data necessary for decoding the first coded data, and each part of the second coded data, The auxiliary information detecting means for detecting whether or not all the information necessary for decoding the first encoded data is included, and the auxiliary information detecting means detects that the information necessary for decoding is missing. Necessary information generating means for generating necessary information from the remaining portion of the second encoded data and adding it to the second encoded data, and data is added by the necessary information generating means. Second code after The data and the first encoded data and is characterized in that it comprises a data rearrangement unit rearranges the order in which the decoder accepts.

[0010]

According to the present invention, even if data is duplicated, the duplicated portion is detected, deleted, and rearranged so as to be corrected by the decoder to enable special reproduction. Further, even when data is missing, the missing part is detected, and encoded data corresponding to the position is generated so that the data is corrected by the decoder so that special reproduction can be performed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a video signal reproducing apparatus of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a video signal reproducing apparatus according to the first embodiment of the present invention. In the figure, 1 is an error correction encoder, 2, 4, 5 are buffer memories, 3 is an encoded data separator, 6 is an encoding position information detector, 7 is an encoding position information comparator, and 8 is an overlap. A data deleter 9 is a data rearranger. The operation is shown below.

The encoded data input from the recording medium is
The error correction code is removed by the error correction decoder 1 and a predetermined number of m frames (m is an arbitrary number) are stored in the buffer memory 2. With the encoded data separator 3,
Auxiliary data such as various headers is detected and separated from the accumulated encoded data. Hereinafter, the separated data (auxiliary data) will be referred to as second encoded data, and the remaining data will be referred to as first encoded data. The first encoded data is the buffer memory 4, and the second encoded data is (for auxiliary data)
It is stored in the buffer memory 5.

The coded position information detector 6 outputs the coded position information indicating the coded data of each macroblock in the first coded data, which coded which macroblock of what frame. Read from the header at the corresponding position in the second encoded data. The coded position information comparator 7 compares the coded position information of each macroblock to check for data duplication. The duplicated data remover 8 removes the duplicated portion from the first and second encoded data based on the duplicated information of the encoded position information comparator 7.

In normal reproduction, data duplication does not occur in all frames and all macroblocks.
In this case, there is no data to delete. Also in normal playback,
If the special reproduction data is separately recorded at the time of recording, the macro blocks in that portion overlap, and therefore the special reproduction data is deleted with priority over the normal reproduction data.

In slow reproduction, the head may read data from the same track more than once. In this case, the data of one macro block is left and the remaining data is deleted. During n-fold speed (where n is an arbitrary number) high-speed playback, the screen is played back at a rate of 1 frame per n frames, but data for 1 frame (within the range of n frames during normal playback) There is a case where a plurality of data of macroblocks at the same position are obtained in duplicate while acquiring. At this time, the data of the macroblock of the frame that is newest in time is left and the remaining data is deleted. The first and second encoded data from which the duplicated portions have been eliminated by the duplicated data eliminator 8 are rearranged in the order accepted by the decoder by the data rearranger 9 and output.

With the above structure, when the data of the same macroblock is read out a plurality of times during slow reproduction, only one of them is read out, or the position of which is occupied on the screen although the frame number is different during high speed reproduction. When the data of the same macroblock is read out, the data of the latest macroblock in it is retained and the others are deleted and rearranged, so that the data can be read as it is without any special operation by the decoder. It can be decrypted and reproduced.

FIG. 2 shows a block diagram of a video signal reproducing apparatus according to the second embodiment of the present invention. In the figure, 1 is an error correction encoder, 2, 4, 5 are buffer memories, 3 is an encoded data separator, 6 is an encoding position information detector, 9 is a data rearranger, and 10 is an encoding position. Information comparator, 11
Is a data generator, and 12 is a memory. The error correction encoder 1, the buffer memories 2, 4, 5, the encoded data separator 3, the encoded position information detector 6, and the data rearranger 9 have the same configurations as in the first embodiment. The operation is shown below.

The encoded data input from the recording medium is
The error correction code is removed by the error correction decoder 1 and a predetermined number of m frames (m is an arbitrary number) are stored in the buffer memory 2. With the encoded data separator 3,
Auxiliary data such as various headers is detected and separated from the accumulated encoded data. Hereinafter, the separated data (auxiliary data) will be referred to as second encoded data, and the remaining data will be referred to as first encoded data. The first encoded data is stored in the buffer memory 4, and the second encoded data is stored in the (for auxiliary data) buffer memory 5.

The coded position information detector 6 outputs coded position information indicating the coded data of each macroblock in the first coded data, which coded which number of macroblocks of which frame. Read from the header at the corresponding position in the second encoded data. The encoded position information comparator 10 is
The coding position information of each macroblock is compared with each other to check for missing data on the screen to be decoded. The data generator 11 generates and replenishes the missing part of the encoded data based on the data omission information from the encoded position information comparator 10.

In normal reproduction, data loss does not occur in all frames and all macroblocks.
In this case, there is no data to generate and replenish. Even in normal reproduction, an error may occur during reproduction, a part of the encoded data may drop out, and a macroblock that cannot be reproduced may occur. When n times (where n is an arbitrary number) high-speed playback, macroblock data at all positions can be obtained while acquiring data for one frame (within n frames during normal playback) Is few. In these cases, it is necessary to generate and supplement the missing macroblock data.

As a first method of generating and supplementing, the coded data of the macroblock is set in the mode of "interframe coding, no coded data" and generated, and the macroblock of the previous screen is displayed as it is.

As a second method of generating and supplementing, when the motion vector of the macro block is obtained, the coded data is set to the mode of "interframe coding, motion compensation, no coded data". Then, the macroblock that has been generated and motion-compensated from the previous screen is displayed.

As a third method of generating and supplementing, when the modes of the above two methods are not allowed, the coded data of the latest decoded screen is recorded in the memory 12 and the code of the macro block at the same position is recorded. Generated data is copied from the memory 12.

As a fourth method of generating and supplementing, the memory 12
The coded data that has been subjected to the latest intra-frame coding in each macroblock is recorded in, and the coded data of the macroblock at the same position is copied from the memory 12 and generated.

As a fifth method of generating and supplementing, the DC component and DCT coefficient of each DCT block in the macroblock are generated from data recorded separately for peripheral diversion, interpolation and special reproduction.

The first and second encoded data, in which the missing parts are generated and supplemented by the data generator 11, are rearranged in the order accepted by the decoder by the data rearranger 9 and output.

With the above configuration, when data of a macroblock is missing due to an error, high-speed reproduction, etc., the data of the macroblock at that position is generated, supplemented, and rearranged so that the decoder does not perform a special operation. In both cases, the data can be decrypted and reproduced as it is.

FIG. 3 shows a block diagram of a video signal reproducing apparatus according to the third embodiment of the present invention. In the figure, 1 is an error correction encoder, 2, 4, 5 are buffer memories, 3 is an encoded data separator, 6 is an encoded position information detector, 9 is a data rearranger, and 20 is auxiliary data detection. , 21 is an auxiliary data generator, and 22 is a memory. The error correction encoder 1, the buffer memories 2, 4, 5, the encoded data separator 3, the encoded position information detector 6, and the data rearranger 9 have the same configurations as those of the first and second embodiments. Is. The operation is shown below.

The encoded data input from the recording medium is
The error correction code is removed by the error correction decoder 1 and a predetermined number of m frames (m is an arbitrary number) are stored in the buffer memory 2. With the encoded data separator 3,
Auxiliary data such as various headers is detected and separated from the accumulated encoded data. Hereinafter, the separated data (auxiliary data) will be referred to as second encoded data, and the remaining data will be referred to as first encoded data. The first encoded data is stored in the buffer memory 4, and the second encoded data is stored in the (for auxiliary data) buffer memory 5.

The coded position information detector 6 outputs the coded position information indicating the coded data of each macroblock in the first coded data, which coded which macroblock of what frame. Read from the header at the corresponding position in the second encoded data. The auxiliary data detector 20 checks auxiliary data for decoding the encoded data of each macroblock, which is not included in the second encoded data. The auxiliary data generator 21 is the auxiliary data detector 2
Based on the auxiliary data information from 0, the missing part of the auxiliary data is generated and supplemented.

In the case of normal reproduction, there is no omission of auxiliary data in all frames and all macroblocks, and in this case there is no data to be generated and supplemented. Even during normal reproduction, an error may occur during reproduction, a part of the auxiliary data may drop out, and a macroblock that cannot be reproduced may occur. During high-speed reproduction of n times (where n is an arbitrary number), auxiliary data is also lost while acquiring data for one frame (within the range of n frames during normal reproduction). In these cases, it is necessary to generate and supplement the missing macroblock data.

As a first method of generating and supplementing, the memory 22
The auxiliary data of the latest decryption screen is recorded in and the auxiliary data of the macroblock at the same position is copied from the memory 22 and generated.

As a second method of generating and supplementing, the data is generated from data recorded separately for peripheral diversion, interpolation and special reproduction.

The first and second encoded data generated and supplemented by the auxiliary data generator 21 are rearranged in the order received by the decoder by the data rearranger 9 and output.

With the above configuration, when the auxiliary data is lost due to an error, high-speed reproduction, etc., the auxiliary data at that position is generated and supplemented and rearranged so that the decoder can perform the operation without any special operation. It can be decrypted and reproduced.

In the above description, several kinds of generation / replenishment methods are shown, but other generation / replenishment methods may be used.

Although the encoding position information and the auxiliary data are detected for each macroblock, this may be detected for each unit in which a plurality of macroblocks are collected, each screen, or other unit.

[0039]

As described above, the video signal reproducing apparatus according to the present invention can duplicate coded data even when missing or duplication of coded data occurs due to special playback such as slow playback or high speed playback. By detecting and deleting a part, or by detecting a missing coded data part and generating and supplementing it, the coded data is corrected so that the decoder can accept it, and special reproduction is enabled.

[Brief description of drawings]

FIG. 1 is a block diagram of a video signal reproducing device according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a video signal reproducing device according to a second embodiment of the present invention.

FIG. 3 is a block diagram of a video signal reproducing device according to a third embodiment of the present invention.

FIG. 4 is a block diagram of a conventional playback device.

[Explanation of symbols]

 1 Error Correction Encoder 2, 4, 5 Buffer Memory 3 Encoded Data Separator 6 Encoded Position Information Detector 7, 10 Encoded Position Information Comparator 8 Duplicate Data Remover 9 Data Sorter 11 Data Generator 12 , 22 memory 20 auxiliary data detector 21 auxiliary data generator

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display area H04N 7/24 H04N 7/13 Z

Claims (7)

[Claims] 1. A storage means for storing coded data acquired from a recording medium within a predetermined time, a screen number on a coded video signal, and a position occupied on the screen for each part of the coded data. Coding position information detecting means for obtaining coding position information which is information indicating the coding position, and coding for comparing the coding position information of each part of the coded data with the coding position information of the remaining part of the coded data. Position information comparing means, and a first data portion in which encoded data occupying the same position on the screen exists in the remaining portion as a result of the comparison,
In the overlapping part classification means for classifying into the second data part in which the remaining part has no coded data occupying the same position on the screen, and the data belonging to the first data part,
The data deleting means for deleting a part of the coded data so as to eliminate duplication occupying the same position on the screen, and the coded data after the data has been deleted by the data deleting means are arranged in the order in which the decoding section receives them. A video signal reproducing apparatus comprising a data rearranging means for rearranging data. 2. The data deleting means deletes the other coded data part of the coded data occupying the same position on the screen, leaving the coded data part having the latest screen number. Item 1. The video signal reproducing device according to Item 1. 3. Storage means for storing coded data acquired from a recording medium within a predetermined time, and a screen number on the coded video signal and a position occupied on the screen for each part of the coded data. And a position not included in any of the positions occupied on the screen in all parts of the coded data among the positions on the screen. An unprocessed position detecting means for detecting a certain unprocessed position, an encoded data generating means for generating encoded data for decoding the unprocessed position, and adding the encoded data to the encoded data, and the encoded data generating means. A video signal reproducing apparatus, comprising: a data rearranging unit that rearranges encoded data added with data in an order received by a decoding unit. 4. The coded data generating means comprises means for generating a DC component of each block in the unprocessed portion and means for generating a signal indicating a delimiter of each block. The described video signal reproducing device. 5. The coded data generation means corresponds to the latest screen coded data storage means for storing the latest screen of the coded data decoded and reproduced up to that point, and each block in the unprocessed portion. 4. The video signal reproducing apparatus according to claim 3, further comprising means for reading out a portion from the latest screen encoded data storage means. 6. Storage means for storing coded data obtained from a recording medium within a predetermined time, and first coded data which is data obtained by coding the accumulated data.
Coded data classification means for classifying into the second coded data, which is the coded data necessary for decoding the first coded data, and each part of the second coded data, The auxiliary information detecting means for detecting whether or not all the information necessary for decoding the first encoded data is included, and the auxiliary information detecting means detects that the information necessary for decoding is missing. The necessary information is generated from the remaining part of the second encoded data,
Necessary information generating means to be added to the encoded data of No. 2, and the second encoded data and the first encoded data after the data is added by the required information generating means are rearranged in the order received by the decoding unit. A video signal reproducing apparatus comprising a data rearranging means. 7. The necessary information generating means detects common information common to the entire sequence in the encoded data, common information in each screen, and common information across a plurality of blocks to detect all or a part of the common information. 7. A video signal reproducing apparatus according to claim 6, further comprising: a detection unit and an auxiliary data selection unit that selects data necessary as auxiliary data from information common to each range detected by the common information detection unit. apparatus.