KR100499457B1 - Apparatus for processing multi broadcasting signal in digital broadcasting receiver - Google Patents

Abstract

The present invention relates to a multi-broadcast signal processing apparatus of a digital broadcasting receiver that simultaneously outputs two types of analog signals regardless of the analog format of a digital broadcasting system. In particular, in one NTSC / PAL encoder using two NTSC / PAL encoders, The video decoder converts the restored video data into an analog signal corresponding to the broadcast system that is receiving the video signal, and the other NTSC / PAL encoder outputs the analog data of a different method from the broadcast system receiving the restored video data. By converting to a signal and outputting, two analog signal formats (NTSC and PAL) can always be output regardless of which digital broadcasting system receives the analog format (NTSC or PAL). Only analog format supported Conventional TVs can also display signals in other analog formats received. In addition, by enabling the use of broadcasting services of other countries or broadcasters that do not have the same analog format that may occur in the digital broadcasting era in the future, it is possible to further enhance the competitiveness of the receiver.

Description

Multi-broadcast signal processing device for digital broadcast receivers {APPARATUS FOR PROCESSING MULTI BROADCASTING SIGNAL IN DIGITAL BROADCASTING RECEIVER}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiver for receiving digital broadcasts, and more particularly, to a multi-broadcast signal processing apparatus for a digital broadcast receiver for simultaneously outputting two types of analog signals regardless of the analog format of a digital broadcast system to receive.

Video signals from TVs vary by country and region, and include NTSC (National Television System Committee), PAL (Phase Alternation by Line; TV in Western Europe except France), SECAM (in France and Eastern Europe). There are three kinds of TV system).

Accordingly, digital broadcasting encodes a digital signal into an analog signal (for example, a PAL or NTSC signal) in accordance with an analog broadcasting system format of a service host country to perform analog output.

FIG. 1 is a block diagram illustrating a conventional digital broadcast receiver, in which one of a plurality of channels received through an antenna is selected by a tuner and demodulated, and then output to a transport packet (TP) demultiplexer 11. When the TP demultiplexer 11 is demultiplexed according to a video packet identification (PID) to be actually decoded, the TP demultiplexer 11 selects a desired program among a plurality of programs multiplexed on one channel, and multiplexed on the selected program. Separate audio and video bitstreams. The separated video bitstream is output to the video decoder 12.

The video decoder 12 removes overhead (various header information, start codes, etc.) from a video bit stream input according to the MPEG video standard, and performs variable length decoding (VLD) of pure data information. The pixel value of the original screen is restored through a quantization process, an inverse discrete cosine transform (IDCT), and a motion compensation process using a motion vector.

The reconstructed image is output to the NTSC / PAL encoder 13, and the NTSC / PAL encoder 13 encodes the reconstructed image according to a broadcast method of a receiver so that display of the reconstructed image is possible, and thus the final analog signal. Will output

Here, the video decoder 12 synchronizes the PIXCLK, the vertical synchronization signal and the horizontal synchronization signal with the ITU-R Rec. 656 (601) format image data is output, and the NTSC / PAL encoder 13 outputs the received image data as analog signals in accordance with vertical and horizontal synchronization signals generated according to the set analog format.

The conventional digital broadcasting receiver as shown in FIG. 1 outputs only one analog format (NTSC or PAL) according to the broadcasting method of the receiving broadcasting system. That is, only NTSC analog signals are output or PAL analog signals are output. However, even with the digital satellite broadcasting system, which is now widely commercialized, the border of radio waves disappears, and neighboring countries with different analog formats are included in the visible area. Nevertheless, when using a conventional TV, it is inconvenient to receive broadcasts of neighboring countries having different analog formats. In other words, the TV supporting the PAL signal format cannot see the NTSC signal at all, and the TV supporting the NTSC signal format cannot see the PAL signal at all.

Also, in the near future, an era in which a transmission system will start a service by allocating channels of analog format used in each country by viewing frequency in a plurality of countries as viewers will be required, and thus, a need for a receiver capable of receiving them is required.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide an apparatus for processing a multi-broadcast signal of a digital broadcast receiver so that digital broadcasts in neighboring areas having different analog formats can also be serviced.

In the multi-broadcast signal processing apparatus of the digital broadcast receiver according to the present invention for achieving the above object, the image reconstructed by the video decoder in one NTSC / PAL encoder using two NTSC / PAL encoder, memory control unit, memory The NTSC / PAL encoder converts the image data reconstructed by the video decoder into an analog signal different from that of the receiving broadcast system and outputs the converted analog signal corresponding to the broadcasting system receiving the data. It is characterized by.

The memory controller may simultaneously output analog signals of different formats by bypassing the image data input to the memory to the second encoder when the image data sizes of the two analog formats are the same and the number of frames per second is the same.

The memory controller converts the image data inputted to the memory into a data rate and format required by the second encoder when the image data size and the number of frames per second are different from each other by outputting the image data to the second encoder. It simultaneously outputs analog signals.

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

FIG. 2 is a block diagram illustrating an apparatus for processing a multicast signal of a digital broadcasting receiver according to the present invention. In order to simultaneously output an NTSC signal and a PAL signal, the TP demultiplexer 21, the video decoder 22, and the NTSC / PAL of FIG. NTSC / for analog output of a broadcasting scheme different from the broadcasting scheme output from the memory control unit 24, the memory 25 storing the output of the video decoder 22 in the encoder 23, the NTSC / PAL encoder 23; A PAL encoder 26 was added.

In the present invention configured as described above, one channel among the plurality of channels received through the antenna is selected by the tuner and demodulated and then input to the Transport Packet (TP) demultiplexer 21. The TP demultiplexer 21 selects a desired program among a plurality of programs multiplexed in one channel according to a video packet identification (PID) to be actually decoded, and audio and video bits multiplexed in the selected program. Separate the stream. The separated video bitstream is output to the video decoder 22.

The video decoder 22 removes overhead (various header information, start codes, etc.) from the video bit stream input according to the MPEG video standard, and after VLD of pure data information, uses dequantization, IDCT, and motion vectors. The motion compensation process restores the pixel values of the original screen.

The reconstructed image data is stored in the NTSC / PAL encoder 23 and the memory 25 in synchronization with the PIXCLK1, V_Sync1, and H_Sync1 signals output from the NTSC / PAL encoder 23.

The NTSC / PAL encoder 23 is configured to display digital image data inputted to enable display in accordance with the corresponding NTSC or PAL standard of the digital broadcasting system. 656 (601) format is converted and output. If the current broadcast system is NTSC system, NTSC analog signal is output, and if PAL system, PAL analog signal is output.

In addition, the memory 25 stores image data reconstructed by the video decoder 22 under the control of the memory controller 24, and the memory controller 24 outputs the PIXCLK1 output from the NTSC / PAL encoder 23. , The video data restored by the video decoder 22 in synchronization with the V_Sync1 and H_Sync1 signals are stored in the memory 25 and synchronized with the PIXCLK2, V_Sync2, and H_Sync2 signals output from the NTSC / PAL encoder 26 to the memory 25. The stored data is output to the NTSC / PAL encoder 26.

The NTSC / PAL encoder 26 converts the image data output from the memory 25 into an ITU-R Rec. In the 656 (601) format, the NTSC / PAL encoder 26 outputs an analog signal of the PAL method, and outputs an NTSC analog signal if the broadcast system being received is an NTSC method.

That is, the two NSTC / PAL encoders 23 and 26 output analog signals of different broadcasting methods. For example, if the NTSC / PAL encoder 23 outputs an analog signal corresponding to the broadcast system currently being received, the NTSC / PAL encoder 26 outputs an analog signal different from the broadcast system currently being received. .

The following describes how to convert analog formats into the following formats.

NTSC and PAL are color signal coding parameters, and B, D, G, H, I, K, K1, L, M and N are TV signal transmission (system) parameters. Among the transmission parameters, M consists of 525 lines of one frame and 30 frames per second. Other parameters consist of 625 lines per frame and 25 frames per second.

If the analog format of the received broadcast is different from the color signal coding parameter of the analog format to be converted, the NTSC / PAL encoder 26 shown in FIG.

In addition, let us consider a case where the TV signal transmission parameters are different.

In the first case, if the two analog formats have a parameter other than M or have the same M, since the image data size is the same and the number of frames per second is equal, the memory control unit 24 controls the NTSC image data input to the memory 25. This can be achieved simply by bypassing the / PAL encoder 26.

In the second case, if one of the two analog formats is M and the other has a parameter other than M, the image data size is 740 x 480 for M, 30 frames per second, and for M other than 740 x 576, the number of frames per second is 25 so that the memory control unit 24 converts the image data input into the memory 25 into the transfer rate and format required by the NTSC / PAL encoder 26 to the NTSC / PAL encoder 26. Can be implemented by printing

A detailed block of the memory controller 24 and a detailed block of the memory 25 for this purpose are shown in FIG. 3.

In FIG. 3, the memory controller 24 is composed of a video timing controller 31, a bus timing generator 32, an address controller 33, a bus controller 34, and a memory interface 35. The memory 25 can be roughly divided into four banks BANK0 to BANK3. Each bank has a maximum size of 720 ㅧ 576 ㅧ 12 bits and is configured to buffer one field.

That is, the video timing controller 31 includes three synchronization signals PIXCLK1, V_Sync1 and H_Sync1 generated by the NTSC / PAL encoder 23 and three synchronization signals PIXCLK2, generated by the NTSC / PAL encoder 26. After receiving V_Sync2 and H_Sync2), obtain the difference by comparing each V_Sync signal. Here, PIXCLK1 and PIXCLK2 are the same signals as clocks synchronized with the digital broadcasting system clock at the receiver. Therefore, the difference between the vertical synchronization signals of the two NTSC / PAL encoders 23 and 26 appears repeatedly with the values T0 to T4 of five levels as shown in FIG.

For example, if V_Sync1 is not the transmission parameter of M (see a in FIG. 4), and V_Sync2 is the transmission parameter of M (see b in FIG. 4), the video timing controller 31 uses regularity to perform Perform the following operation.

1) When the system data is activated for the first time and the image data is valid, data is not stored or read in the memory 25 until the time when V_Sync1 and V_Sync2 is T = 4.

2) When T = 4, the video data output from the video decoder 22 is only written to the memory 25 in accordance with each H_Sync1.

3) The video data output by the video decoder 22 in accordance with each H_Sync1 is written to the memory 25 at a time point T = 0, and then the NTSC / PAL encoder 26 is written to the memory 25 in accordance with H_Sync2. Output the data of the previous field.

4) Repeat 3) until T = 4.

5) If T = 0, the video data output by the video decoder 22 in accordance with each H_Sync1 is written into the memory 25, and then stored in the memory 25 by the NTSC / PAL encoder 26 in accordance with H_Sync2. Repeatedly print the data of the previous field.

6) Repeat 4) and 5) above.

In contrast, when V_Sync1 has a transmission parameter of M and V_Sync2 does not have a transmission parameter of M, the video timing controller 31 performs the following operation using regularity.

1) When the system data is activated for the first time and the image data is valid, data is not stored or read in the memory 25 until the time when V_Sync1 and V_Sync2 is T = 0.

2) At the time T = 0, the video data output by the video decoder 22 in accordance with each H_Sync1 is written to the memory 25, and then stored in the memory 25 by the NTSC / PAL encoder 26 in accordance with H_Sync2. Print the data of the previous field.

3) The video data output by the video decoder 22 in accordance with each H_Sync1 is written into the memory 25 until T = 4, and then stored in the memory 25 by the NTSC / PAL encoder 26 in accordance with H_Sync2. Print the data of the previous field.

4) The video data output by the video decoder 22 in accordance with each H_Sync1 is discarded when T = 4 is matched, and the data of the previous field stored in the memory 25 by the NTSC / PAL encoder 26 in accordance with H_Sync2. Outputs

5) Repeat 3) to 4) above.

At this time, the address controller 33 outputs the address determined by the control signal from the video timing controller 31 to the memory 25, and the bus timing generator 32 and the bus controller 34 refresh the memory 25. Generates refresh cycles and memory read or write timings.

5 is a method of simply implementing a difference in the number of lines per frame, and FIG. 5A shows that the transmission parameter of the analog broadcasting system of the receiving local broadcasting system is M rather than the transmission parameter of the analog broadcasting system of the receiving signal broadcasting system. The display state for the case is shown as a frame. The output video data frame size of the original video decoder 22 is 720 x 576, and the size of the video data frame to be converted is 720 x 480. By simply discarding lines 1 to 48 and lines 528 to 576, the frame size is simply Is converted and synchronized by outputting the previously converted frame once the difference between the two vertical synchronizations is T = 0.

FIG. 5B shows a display state in a frame when the analog transmission parameter of the received signal broadcasting system is M and the analog transmission parameter of the receiving local broadcasting system is not M. FIG. Originally, the output image data frame size of the video decoder 22 is 720, 480, and the image data frame size to be converted is 720 576, which is simply lines 1 to 48 and lines 528 to 576. Black Background Color) data is supplemented, and the frame size is simply converted, and synchronization can be achieved by discarding the output image data frame of the video decoder 22 when the difference between the two vertical synchronizations is T = 4.

This implementation has the advantage of being very simple to implement, but has the disadvantage of showing distortion of the original signal.

A method for overcoming this disadvantage can be overcome by adding a vertical filter to the memory controller 24.

As described above, according to the multi-broadcast signal processing apparatus of the digital broadcast receiver according to the present invention, regardless of which digital broadcast system transmits the analog format (NTSC or PAL) to always receive two analog signal formats (NTSC and PAL) By outputting, it is possible to display a signal of another analog format received even with an existing TV which supports only one analog format suitable for the receiving broadcast system. In other words, even when receiving NTSC signal digital broadcast, PAL signal can be output and vice versa, so that the conventional TV can watch different broadcast format without any inconvenience.

In addition, by enabling the use of broadcasting services of other countries or broadcasters that do not have the same analog format that may occur in the digital broadcasting era in the future, it is possible to further enhance the competitiveness of the receiver.

1 is a block diagram of a conventional digital broadcast receiver

2 is a block diagram illustrating an apparatus for processing a multicast signal of a digital broadcast receiver according to the present invention.

3 is a detailed block diagram of a memory controller and a memory of FIG. 2;

4 is a timing diagram for two vertical synchronization signals of FIG.

5A is a diagram illustrating a display state when the analog transmission parameter of the reception signal broadcasting system is not M and the analog transmission parameter of the receiving local broadcasting system is M. FIG.

5B is a diagram illustrating a display state when the analog transmission parameter of the received signal broadcasting system is M and the analog transmission parameter of the receiving local broadcasting system is not M.

Explanation of symbols for main parts of the drawings

21: TP Demultiplexer 22: Video Decoder

23,26: NTSC / PAL encoder 24: memory controller

25: memory

Claims (3)

A demultiplexer that separates and outputs only the pure video bitstream by demultiplexing when a compressed multiple bitstream is input; A video decoder which decodes the video bitstream output from the demultiplexer using an MPEG algorithm and then outputs in synchronization with the input first synchronization signal; A first NTSC / PAL encoder for outputting a first synchronization signal to the video decoder, converting the analog signal corresponding to the broadcast method received from the video decoder in synchronization with the first synchronization signal, and outputting the analog signal; A memory for storing image data reconstructed by the video decoder; A memory controller configured to store image data reconstructed by the video decoder in the memory in synchronization with a first synchronization signal output from the first NTSC / PAL encoder, and output stored image data in synchronization with a second synchronization signal input; , Outputting a second synchronization signal to the memory control unit, and converting and outputting image data output in synchronization with the second synchronization signal from the memory through the memory control unit to an analog signal of a method different from the broadcasting method And a second NTSC / PAL encoder. The method of claim 1, wherein the memory control unit Digital broadcasting characterized by simultaneously outputting analog signals of different formats by bypassing the video data inputted to the memory to the second NTSC / PAL encoder when the video data sizes of the two analog formats are the same and the number of frames per second is the same. Receiver for multi-broadcast signal processing. The method of claim 1, wherein the memory control unit If the video data size and the number of frames per second of the two analog formats are different, the video data inputted to the memory is converted to the data rate and format required by the second NTSC / PAL encoder, and then output to the second NTSC / PAL encoder. A multi-broadcast signal processing apparatus for a digital broadcast receiver, characterized in that it simultaneously outputs an analog signal of the type.

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