JPH05290526A - Signal processing method for digital video signal - Google Patents

Abstract

PURPOSE:To correct error data on a reception side by transmitting reproduction data to other equipments in a digital recording and reproducing device. CONSTITUTION:When data reproduced by a recording medium 109 exceed the correction capability of an error correction decoder 111, an error correction decoder 111 outputs error flag as error information and based on the error flag, corrected data are outputted to a monitor TV. The reproduction data and the error flag are transmitted to the dubbing output to the other equipements. The correction is performed at all times in the case of reproducing the error data by recording the transmitted signal as it is.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal processing method for video signals of a digital recording / reproducing apparatus.

[0002]

2. Description of the Related Art In a digital recording / reproducing apparatus, an error generated during reproduction is corrected based on an error correction check symbol added during recording, and an error is corrected for uncorrectable data. The configuration and operation of the digital recording / reproducing apparatus and the error correction method will be described below.

FIG. 4 is a block diagram showing a conventional digital recording / reproducing apparatus, wherein 1 is a terminal, 2 is an A / D converter, and 3
Is a high-efficiency encoder, 4 is an error correction encoder, 5 is a recording processor, 6 is a recording medium, 7 is a reproduction processor, 8 is an error correction decoder, 9 is a modifier, and 10 is high efficiency decoding. And 11 is D
A / A converter, 12 is a terminal.

A digital recording / reproducing apparatus configured as described above will be described. First, at the time of recording, the signal input from the terminal 1 is A / D-converted by the A / D converter 2, compression-encoded by the high-efficiency encoder 3, and error-correcting code by the error-correcting encoder 4. Recording processor 5 with added
And is recorded on the recording medium 6. When recording a digital signal of a digital dubbing input, the signal inputted after the high-efficiency encoder 3 is subjected to the same processing and recorded.

Next, at the time of reproducing, the data reproduced from the recording medium 6 is reproduced by the reproducing processor 7 and input to the error correction decoder 8. The error correction decoder 8 corrects the error of the reproduction signal based on the error correction check symbol added at the time of recording, and when an error exceeding the correction capability occurs, an error flag indicating the existence of the error is set. Output. The reproduced data in which the correctable error is corrected is sent to the retouching device 9. The modifier 9 performs error correction based on the error flag. The modifier 9 performs processing such as interpolating erroneous data from neighboring data or replacing it with corresponding past data. The data that has been subjected to error correction by the modifier 9 is compressed and decoded by the high efficiency decoder 10,
It is D / A converted by the D / A converter 11 and connected to a monitor TV, a video printer or the like via a terminal 12. The output of the modifier 9 is used as the digital signal of the digital dubbing output.

[0006]

However, the above-mentioned signal processing method for digital video signals has the following problems.

That is, when there is an error that cannot be corrected by the error correction process in the reproduced data, the correction is performed. For example, in the case where the data is output as digital data in a high efficiency coded state, it is corrected. However, there is a problem that when the data is modified and output, the modification needs to be performed in a high-efficiency encoded state, and the modification method is limited.

SUMMARY OF THE INVENTION The present invention solves the problems of the prior art, and an object of the present invention is to provide a signal processing method of a digital video signal for transmitting error information to an external device to prevent deterioration of image information.

[0009]

The present invention provides an error correction means for correcting an error of data reproduced from a recording medium, data corrected by the error correction means, and a correction result of the error correction means. An error flag indicating the presence of an originally set error and an output unit for outputting the error to the outside, and when the output data has an error that cannot be corrected by the error correction unit, the error A signal processing method for a digital video signal, wherein the presence of an error can be detected by a flag.

[0010]

According to the present invention, when the data reproduced from the recording medium is subjected to error correction processing and output as digital data, the present invention outputs the error flag indicating the existence of an error. If there is an uncorrectable error, the existence of the error can be confirmed by referring to the error flag.

[0011]

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

FIG. 1 is a block diagram showing a configuration of a digital recording / reproducing apparatus for realizing a signal processing method of a digital video signal according to an embodiment of the present invention, in which 100 is an input terminal and 101 is an A / D converter. , 102 is a memory, 103 is a high efficiency encoder, 104 is a terminal, 105 is a digital input processor, 106 is a switching SW, 107 is an error correction encoder, 108 is a recording processor, 109 is a recording medium, and 110 is Reproduction processor, 111 error correction encoder, 112 error flag multiplexer, 113 switch SW, 114 high efficiency decoder, 115 error modifier, 116 digital output processor, 117 D / A A converter, 118 is a terminal, and 119 is a terminal.

First, recording will be described. Input terminal 1
The video signal input from 00 is A / D converted by the A / D converter 101, the video data of one field is collected into a plurality of data blocks, and the data is input to the memory 102. The memory 102 rearranges the video data in order to reduce the influence of burst loss during reproduction. After rearranging the data, it is compression-encoded by the high-efficiency encoder 103 and switched S
After W106, an error correction code is added by the error correction encoder 107, and after the recording processing by the recording processor 108,
The data is recorded on the recording medium 109. In the case of dubbing input, the digital dubbing signal input from the terminal 104 is processed by the digital input processor 105 for transmission data, and is input to the error correction encoder 107 via the switching SW 106. Subsequent recording processing is the same as that described above, and will be omitted.

Next, reproduction will be described. Reproduction processor 1
The data reproduced from the recording medium 109 by 10 is error-corrected by the error-correction decoder 111, and when an error exceeding the correction capability occurs, an error flag indicating the existence of the error is set as the error-correction flag. Multiplexer 112
Output to. The reproduction data subjected to the error correction processing by the error correction decoder 111 is input to the correction flag multiplexer 112. The correction flag multiplexer 112 multiplexes the error flag output from the error correction decoder 111 for each predetermined unit (data block) of the error-correction-processed high-efficiency coded data as shown in FIG. To do. The data in which the error flag is multiplexed is passed through the switching SW 113 and the high efficiency decoder 1 is provided.
The data is compressed and decoded at 14 and input to the error modifier 115.
The error flag is separated by the high efficiency decoder 114 and input to the error modifier 115. The error modifier 115 performs error correction after high efficiency decoding based on the error flag. The modified data is D by A / D converter 117.
A / A is converted and the terminal 118 is connected to a monitor TV or the like.
When outputting to another device as dubbing data (hereinafter referred to as digital dubbing), a signal of a format in which an error flag and an error flag are multiplexed with the above-described data in the high efficiency coding state is digitally output by the switching SW 113. It is input to the processor 116, converted into a transmission format, and output from the terminal 119.

Next, data transmission by digital dubbing will be described. The digital dubbing output transmits a signal in a format in which an error flag is multiplexed with data as described above. The processing when digital dubbing data is input to the receiving side is shown below.

An error correction code is added to a data block in which an error flag is multiplexed and recorded. First, when the digitally input data is reproduced and confirmed on the monitor TV, the erroneous data is modified by switching the switching SWs 106 and 103 and performing the processing after the high efficiency decoding described above. Then, it can be reproduced on the monitor TV in the same manner as the reproducing side device. Further, when recording digitally input data, an error correction check symbol is added and both the data and the error flag are recorded. Therefore, the erroneous data is recorded as it is, and when the data is reproduced next time, the erroneous data is reproduced, but the erroneous data is corrected by the error flag, so that the erroneous signal is not output to the monitor TV. ..

Further, it is not necessary to multiplex the error flag into the data block by setting the data area of only the error flag as shown in FIG.

[0018]

As described above, according to the present invention, since the error flag is recorded together with the data so that the correction is always performed at the position where the flag is present during reproduction, the data block recorded together with the error flag. It is possible to prevent the accumulation of erroneous data because the erroneous data that is output when the correction capability is exceeded by error correction is not recorded as correct data without modifying
It is also possible to prevent deterioration of the retouched image of incorrect data.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a digital recording / reproducing apparatus for realizing a signal processing method of a digital video signal according to an embodiment of the present invention.

FIG. 2 is a data array diagram showing data in which error flags are multiplexed according to an embodiment of the present invention.

FIG. 3 is a data array diagram showing an example in which error flags are collected in a dedicated area according to an embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a conventional recording / reproducing apparatus.

[Explanation of symbols]

 100 Input Terminal 101 A / D Converter 102 Memory 103 High Efficiency Encoder 104 Terminal 105 Digital Input Processor 106 Switching SW 107 Error Correction Encoder 108 Recording Processor 109 Recording Medium 110 Reproduction Processor 111 Error Correction Decoder 112 Error Flag Multiplexer 113 Switching SW 114 High Efficiency Decoder 115 Error Corrector 116 Digital Output Processor 117 D / A Converter 118 Terminal 119 Terminal

Claims (3)

[Claims] 1. An error correction means for correcting an error of data reproduced from a recording medium, data corrected by the error correction means, and an error set based on a correction result of the error correction means. An error flag indicating the presence of an error is output to the outside, and the presence of the error is detected by the error flag when the output data has an error that cannot be corrected by the error correction unit. A method for processing a digital video signal, characterized by: 2. The signal processing method for a digital video signal according to claim 1, wherein the data output to the outside by the output means is highly efficient coded data. 3. The signal processing method for a digital video signal according to claim 1 or 2, wherein the output means adds an error flag to a certain unit of the reproduced data and outputs it.