JPH03241987A - Television signal reproducing device - Google Patents

Abstract

PURPOSE:To enhance an error correction capability for a voice data, especially a control code by allowing a descramble processing means to insert a control code repetitively to an independent data area for a voice data for plural number of times and allowing a conversion processing means to apply majority decision to the plural control codes for the error correction. CONSTITUTION:A majority decision circuit 13m applies serial parallel conversion to 6 bits from the most significant bit of an inputted control code by its shift register, uses a counter to count each bit and applies majority decision to correct its error. Then a voice data processing circuit 13d processes a voice data outputted from a BCH correction circuit 13c based on the control code subject to error correction processing by the majority decision circuit 13m and outputs the result to a D/A converter circuit 13g. Thus, the area of the voice data is effectively in use and the error correction capability of the control code is improved.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a television signal reproduction method in which a scrambled and transmitted television signal is descrambled and then the television format is converted. Regarding equipment,
In particular, the present invention relates to a device that improves error correction ability for audio control data.

(Prior Art) As is well known, when satellite broadcasting such as high-definition broadcasting is charged, in order to view the broadcast on a current NTSC television receiver, it is necessary to adjust the broadcasting television signal. A descrambling processing device for solving added scrambling processing, and a conversion processing device for converting MUSE format television signals to NTSC format,
It becomes necessary to connect to the receiving side.

FIG. 2 shows a conventional television signal reproducing apparatus in which the descramble processing apparatus and the conversion processing apparatus are connected. First, a scrambled television signal supplied to the input terminal 11 is sent to a descrambler 12 for descrambling.

In other words, the television (
No. 2 is the A/'D (analog/digital) conversion circuit 12
After being converted into digital data in step a, it is separated into video data and audio data in a video and audio separation circuit 12b.

Here, the audio data is composed of frames of 1350 bits, and one frame consists of two modes, A and B, as shown in FIGS. 3(a) and (b).
It is possible to select one of the formats. First, mode A consists of a 6-bit frame synchronization signal, a 22-bit control code, a 16-bit range data (1, 2), and an 8x32-bit audio data 1.
8 x 32 bit audio data 2, 16 bit range data (3, 4), 8 x 12 bit audio data 3, 8
32-bit audio data, 4,128-bit independent data and 8x16-bit BCH, iT iE rf. In addition, mode B uses a 16-bit frame synchronization signal, a 22-bit control code, and a 16-bit frame synchronization signal.
Bit range data (1, 2), 11 x 48 bit audio data 1, 11 x 48 bit audio data 2, 11
It consists of 2-bit independent data and an 8x16-bit BCH correction code.

Then, each of the mode A audio data 1 to 4 and each of the mode B audio data 1.2 is subjected to scrambling processing. Further, modes A and B are selected by a control code.

Furthermore, the independent data represents information such as FAX and text multiplexing, and each audio data area 1 to 4 of mode A and each audio data area 1 and 2 of mode B can also be converted into an independent data area by a control code. It is possible.

Here, the audio data separated by the video/audio separation circuit 12b is subjected to bit error correction by the BCH correction circuit 12c based on the BCH correction code added at the time of formatting after scrambling processing on the transmitting side. The audio data subjected to bit error correction by the BCH correction circuit 12c is supplied to a descramble processing circuit 12d, and this descramble processing circuit 12d is driven based on the control code extracted by the control code extraction circuit 12e. The scrambling process is canceled by being controlled by the output of the timing generating circuit 12f. Further, the audio data output from the BCH correction circuit 12c is supplied to a data descrambling device (not shown) via an output terminal P12g, subjected to descrambling processing, and then sent to the outside. Thereafter, the audio data descrambled by the descramble processing circuit 12d is supplied to the BCH addition circuit 12h, where it is reformatted and added with a BCH correction code for error correction, while the audio data is subjected to the video/audio separation process. The video data separated by the circuit 12b is descrambled by the video descrambling processing circuit 12H, and then added to the descrambled audio data output from the BCH addition circuit 12h by the addition circuit 12j. After that, the output of this adder circuit 12j is D/A
The signal is converted into analog data by a (digital/analog) conversion circuit 12, and the descrambling process of the television signal is completed here.

The television signal output from the descrambling processing device 12 is then supplied to a conversion processing device 13, where it is converted from the MUSE system to the NTSC system. That is, the D/A conversion circuit 1 of the descrambling processing device 12
The television signal output from the 2k is converted into digital data by an A/D conversion circuit 13a, and then separated into video data and audio data by a video/audio separation circuit 13b.

Of these, the audio data undergoes bit error correction by the BCH correction circuit 13c based on the BCH correction code added by the descrambling processing device 12.

Thereafter, the audio data error-corrected by the BCH correction circuit 13c is supplied to an audio data processing circuit 1.3d, and this audio data processing circuit 13d is driven based on the control code extracted by the control code extraction circuit 13e. By being controlled by the output of the timing generation circuit 13f, various processes (audio data processing) necessary for audio reproduction are performed. Then, the audio data processing circuit 1
The audio data component outputted from the audio data component 3d is converted into analog data by a D/A conversion circuit 13g, amplified by an amplifier circuit 13h, and used to drive the speaker 13i.

On the other hand, the video data separated by the video/audio separation circuit 13b is supplied to a video data processing circuit 13j, where it is subjected to various processes for format conversion such as scanning line number conversion, time axis conversion, and interpolation processing. Thereafter, the data is converted into analog data by the D/A converter circuit 13, and is provided for image display on the monitor 11, where audio and video are reproduced.

However, in the conventional television signal reproducing apparatus as described above, the audio data to which the BCH correction code has been added by the descrambling processing device 12 is subjected to error correction processing by the conversion processing device 13. The performance is not very high, and it cannot be said that sufficient error correction has been performed for practical purposes. In particular, the descramble processing device 12 and the conversion processing device 13 are not necessarily arranged close to each other, and the longer the transmission distance from the descramble processing device 12 to the conversion device 13, the higher the probability of an error occurring. As this increases, the error correction ability further deteriorates. In this case, if the control code in the audio data becomes incapable of error correction,
This will cause a huge nuisance.

(Problems to be Solved by the Invention) As described above, in the conventional television signal reproducing device,
The problem is that the error correction ability for audio data is low, making it unsuitable for practical use.

Therefore, the present invention was made in consideration of the above circumstances, and an object of the present invention is to provide an extremely good television signal reproducing device that is suitable for practical use by improving the error correction ability of audio data, especially control codes. shall be.

[Structure of the Invention] (Means for Solving the Problems) A television signal reproducing apparatus according to the present invention includes a descrambling means for descrambling a scrambled and transmitted television signal, and a descrambling means for descrambling a scrambled and transmitted television signal. The object of the present invention is a conversion processing means for converting the format of a television signal output from the means.

The descrambling processing means includes an insertion means for repeatedly inserting a control code into the independent data area of the audio data separated from the television signal and inserting the control code multiple times, and the conversion processing means includes a plurality of The apparatus is equipped with a correction means for correcting an error by making a majority decision on the control code.

(Operation) According to the above configuration, the descrambling processing means repeatedly inserts the control code into the independent data area of the audio data multiple times, and the conversion processing means performs a majority decision on the plurality of control codes to correct errors. By doing so, it is possible to improve the error correction ability of audio data, especially for control codes, and to effectively promote practical use.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings. In FIG. 1, the same parts as in FIG. 2 are indicated with the same symbols. That is, in the descrambling processing device 12, the descrambling processing circuit 12d
The audio data descrambled in 1 and the control code extracted in the control code extraction circuit 12e are selectively sent to the BCH addition circuit 12h by a select circuit 12i1 that performs a switching operation based on the output of the timing generation circuit 12f. We are trying to supply it.

In this case, the selection circuit 11 repeatedly inserts the control code extracted by the control code extraction circuit 12e into the independent data area of the audio data in the format shown in FIG. 3 output from the descramble processing circuit 12d. The switching is controlled as follows. Specifically, the control code is 22 bits, but the component that indicates the B78i data format is the first 6 bits, so only those 6 bits are reduced to a minimum of 1.
Insert into an independent data area provided with 12 bits. In other words, the first 6 bits of the control code are
An odd number of codes, including those in the original control code area, will reside in one frame of audio data.

Then, the audio data in which an even number of 6-bit 1 parts from the beginning of the control code are repeatedly inserted into the independent data area as described above is output to the conversion processing device 13. In this case, the conversion processing device 13 is not supplied with independent data in the audio data, or this independent data is data necessary for processing within the data descrambling device connected to the output terminal 12g. Since the data is not required by the conversion processing device 13, no problem will occur even if the data is not supplied to the conversion processing device 13.

Next, in the conversion processing device 13, the control code extracted by the control code extraction circuit 13e (including the first 6 bits of the control code repeatedly inserted in an even number into the independent data area) is processed by the timing generation circuit 13f. The signal is supplied to a majority decision circuit 13m operated based on the output, and after error correction processing is performed by majority decision, it is supplied to an audio data processing circuit 13d. In other words, this majority decision circuit 13m converts the first 6 bits of the human-entered control code into serial/parallel data using a shift register, and then counts each bit using a counter to make a majority decision. This is to make corrections.

Here, the error correction ability of the majority decision circuit 13m will naturally be higher if a large number of control codes are input and the majority decision is made, or the circuit scale will become larger, so in reality, the error correction ability of the majority decision circuit 13m is approximately 8/15. The subcommittee is preferable because the counter for each bit is the smallest and a practically sufficient correction ability can be obtained. Then, the a voice data processing circuit 13d processes the voice data output from the B CH correction circuit 13c based on the control code subjected to error correction processing by the majority decision circuit 13m, and processes the voice data outputted from the B CH correction circuit 13c. It is output to.

Therefore, according to the configuration of the above embodiment, a plurality of control codes are repeatedly inserted in place of the independent data in an area in the audio data where independent data that is not necessary for the conversion processing device 13 is placed. Conversion processing device 1
Since error correction processing is performed by majority decision in step 3, the audio data area can be used effectively and the error correction ability of the control code can be improved.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and can be implemented with various modifications without departing from the scope of the invention.

[Effects of the Invention] As detailed above, according to the present invention, it is possible to provide an extremely good television signal reproducing device which is suitable for practical use by improving the error correction ability of audio data, especially control codes. can.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a television signal reproducing device according to the present invention, FIG. 2 is a block diagram showing a conventional television signal reproducing device, and FIG. 3 is a block diagram showing one embodiment of a television signal reproducing device according to the present invention. FIG. 3 is a diagram showing a format. 11... Input terminal, 12... Descrambling processing device, 12a... A/D conversion circuit, 12b... Video/audio separation circuit, 12c... BCH correction circuit, 12d...
- Descrambling processing circuit, 12e... Control code extraction circuit, 12f... Timing generation circuit, 1
2g...Output terminal, 12h...BCH addition circuit, 1
21... Video descrambling processing circuit, 12j...
・Addition circuit, 12k...D/A conversion circuit, li...
Select circuit, 13... Conversion processing device, 13a...
A/D conversion circuit, 13b... video and audio separation circuit, 13
c... BCH correction circuit, ], 3 d... Audio data processing circuit, 13e... Control code extraction circuit,
13f...timing generation circuit, 13g...D/A
Conversion circuit, 13h...Amplification circuit, 131...Speaker, 13j...Video data processing circuit, 13k...D/
A conversion circuit, 131...monitor, 13m...majority decision circuit.

Claims (1)

[Claims] A television signal reproducing device comprising a descrambling means for descrambling a scrambled and transmitted television signal, and a conversion means for converting the format of the television signal output from the descrambling means. , the descrambling processing means includes insertion means for repeatedly inserting a control code multiple times into an independent data area of the audio data separated from the television signal, and the conversion processing means includes:
A television signal reproducing apparatus characterized in that it comprises a correction means for making a majority decision on the plurality of control codes inserted by the insertion means and correcting an error.