KR100241743B1 - Audio signal processing device for multi-channel - Google Patents

Abstract

end. The technical field to which the invention described in the claims belongs

A device for processing multi-channel audio of multiple standards.

I. The technical problem to be solved by the invention

Provided is an audio processing apparatus capable of processing at least one of NTSC TV broadcasting, DBS broadcasting, and external input, and multi-channel audio according to HD TV broadcasting.

All. Summary of Solution of the Invention

The main channel audio signal L / R is switched by switching the main channel audio signal L / R from the HD audio signal to at least one of the NTSC audio signal L / R and the DBS audio signal L / R and the audio signal L / R according to the external input and the main switch. The sub channel audio signals SR, SL, and C of the HD audio signals are selected and output, and the sub channel audio signals S, C, and the sub switch are additionally generated by the Dolby decoding unit. Select C to print.

la. Important uses of the invention

Used for HD TV broadcast receivers.

Description

Multi Channel Audio Processor

TECHNICAL FIELD The present invention relates to an audio processing apparatus, and more particularly, to an apparatus for processing multi-channel audio of a plurality of standards.

In the existing NTSC (National Television System Committe) TV (Television) broadcasting system, the audio is divided into two analog channels, namely, left and right channels L (Left) and R (Right), and adopts a stereo method. Came. Accordingly, the audio processing apparatus employed in the receiver receiving NTSC TV broadcast only had to process two-channel audio.

Meanwhile, a surround audio system using a larger number of speakers located in different places in the sound listening space is being used to enhance the appearance. Such an audio system is called a multi-channel audio system, for example a Dolby prologic sound system.

FIG. 1 is a block diagram of an audio processing apparatus employed in a Dolby Pro Logic sound system as such a multi-channel audio system. The Dolby decoding unit 100 is controlled by being connected to a MICOM 108 by an IIC bus. ) And volume and tone control unit 106. Audio signals L and R of two channels are input to the Dolby decoding unit 100 including the Dolby decoder 102 and the delayer 104. In this case, the input audio signals L and R may be normal signals or Dolby pro logic signals. The Dolby decoder 102 and the delayer 104 each use a dedicated integrated circuit (IC). For example, the Dolby decoder 102 uses the NJW1102 and the delayer 104 connected to the Dolby decoder 102 is used. NJU9702 is used. The delay 104 is used for pseudo surround or Dolby prologic signal processing in the Dolby decoder 102.

The Dolby decoder 102 processes the audio signals L and R differently under the control of the microcomputer 108 according to the type of the input audio. If it is a standard signal, the Dolby decoder 102 generates two sub-channel audio signals S (Surround) and C (Center) by pseudo surround processing under the control of the microcomputer 108 according to the user's selection. It outputs together with the channel audio signals L and R or otherwise outputs only the main channel audio signals L and R without signal processing. The two audio signals L, R, or four channels of the audio signals L, R, S, and C are output to the volume and tone control unit 106 to adjust the volume and its balance and tone. After that, the sound is output through the corresponding speaker. The volume and tone control unit 106 uses a digitally controlled dedicated IC, for example, TDA7344. At this time, the volume and tone control unit 106 is supplied with the volume and tone control data for adjusting the volume and tone for the main channel audio signals L and R and the volume for the sub channel audio signals S and C from the microcomputer 108. . And the balance is made by volume control.

As described above, the audio processing apparatus is capable of processing Dolby Pro Logic sound by inputting an audio signal composed of two analog channels, thereby not only NTSC TV broadcasting but also DBS (Digital Broadcasting Satellite) broadcasting or Dolby Pro Logic signals according to external input. Could handle without.

On the other hand, in the HD (High Definition) TV to be broadcast in the future, audio will adopt Dolby AC-3 format. The Dolby AC-3 is Dolby's proprietary compression algorithm, defined in the United States HD TV digital audio standard, and provides six channels represented by 5.1 channels. The 5.1 channel is basically composed of five channels, namely, two main channels L and R, three sub-channels SR (Surround Right), SL (Surround Left), and C, which are low frequency channels for driving a subwoofer speaker. One subchannel LFE (Low Frequency Effect) is added. Six speakers for the 5.1 channel can be arranged as follows, for example. That is, the C speaker is located at the front of the listener, the L speaker and the R speaker are arranged at a point of 30 ° from the front to the left and right, respectively, and the RS speaker and the LS speaker are 20 ° rear on the line connecting the left and right of the listener. At the point, the LFE speakers for bass only are in the same position as the C speakers.

As HDTV adopts Dolby AC-3, HD TV receivers must be able to process HD audio signals input through six channels. Also, in the early days of HD TV broadcasting, current TV broadcasting, such as NTSC TV broadcasting, will still continue for some time, so that early HD TV receivers will be produced and marketed for both NTSC TV broadcasting reception. In addition to this, it will be desirable that the HD TV receiver can receive DBS broadcast or input externally. In view of these considerations, an HD TV receiver must employ an audio processing apparatus capable of simultaneously processing at least one audio from among an NTSC TV broadcast, a DBS broadcast, and an external input, and multi-channel audio according to the HD TV broadcast.

On the contrary, the conventional audio processing apparatus such as the audio processing apparatus shown in FIG. 1 as described above can process only one audio signal input through two channels and thus cannot be employed in the HD TV receiver. In addition, in the audio processing apparatus of FIG. 1, the volume and tone control unit 106 receives and processes volume and tone control data directly from the microcomputer 108 by using a digitally controlled IC. As such, the microcomputer 108 and the volume and tone control unit 106 are directly connected to the bus, thereby occupying a large area on the PCB (Printed Circuit Board) due to the bus.

As described above, the HD TV receiver requires an audio processing apparatus capable of processing not only HD TV broadcasting but also multichannel audio according to at least one of NTSC TV broadcasting, DBS broadcasting, and external input. In addition, the volume and tone controls are directly connected to the microcomputer and the bus, which takes up a large area on the PCB.

Accordingly, an object of the present invention is to provide an audio processing apparatus capable of simultaneously processing at least one of NTSC TV broadcasting, DBS broadcasting, and external input and multi-channel audio according to HD TV broadcasting.

Another object of the present invention is to provide an audio processing apparatus capable of reducing the area occupied on a PCB.

1 is a block diagram of a conventional audio processing apparatus;

2 is a block diagram of a multi-channel audio processing apparatus according to an embodiment of the present invention;

3 is a switching control flow diagram of the microcomputer of FIG. 2 in accordance with an embodiment of the present invention.

The present invention for achieving the above-described first object is at least one of the main channel audio signal L / R of the HD audio signal NTSC audio signal L / R, DBS audio signal L / R and the audio signal L / R according to the external input The main channel audio signal L, R is selected and output by switching from the main switch and the main switch, and the sub channel audio signals SR, SL, and C of the HD audio signals are additionally generated by the Dolby decoder. A sub-channel audio signal SR, SL, and C are selected and output by switching between C and a sub switch.

The present invention for achieving the above-mentioned second object is characterized in that the microcomputer adopts an analog control method of the volume and tone control unit to control through the DAC.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description and the annexed drawings, numerous specific details, such as specific circuit elements or control flows, are shown to provide a more general understanding of the invention. It will be apparent to those skilled in the art that the present invention may be practiced without these specific details. In addition, detailed descriptions of well-known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

2 is a block diagram of an audio processing apparatus according to an embodiment of the present invention, and shows an example of processing NTSC TV broadcasting, DBS broadcasting, and multi-channel audio according to external input and HD TV broadcasting. 2 is controlled by the microcomputer 216 according to the current reception mode. In the embodiment of the present invention, the reception mode is divided into NTSC TV mode, DBS mode, external input mode, and HD TV mode. NTSC TV mode is a mode for processing NTSC audio signals L / R received by NTSC TV broadcasting. DBS mode is a mode for processing DBS audio signals L / R received DBS broadcasting. In this mode, the input external audio signal L / R is input and processed, and the HD TV mode is a mode for inputting and processing HD audio signals L / R, SR, SL, C, and LFE received from HD TV broadcasting.

The main switch 200 of FIG. 2 inputs an NTSC audio signal L / R, a DBS audio signal L / R, an external audio signal L / R, and a main channel audio signal L / R of an HD audio signal. The main switch 200 selects one of these inputs corresponding to the reception mode under the control of the microcomputer 216 and outputs the main channel audio signals L and R to the Dolby decoding unit 202. The main switch 200 uses a conventional audio switch.

As described above, the Dolby decoding unit 202 including the Dolby decoder 204 and the delayer 206 is controlled by the microcomputer 216 according to the type of the input audio as described above. L and R signal processing differently. The main channel audio signals L and R output from the Dolby decoding unit 202 are output to the main volume tone control unit 210, and are generated according to pseudo surround or Dolby pro logic signal processing by a user's selection. The two sub channel audio signals S and C are output to the sub switch 208. That is, the Dolby decoding unit 202 generates sub-channel audio signals S and C by pseudo surround signal processing when the standard signal is input, and outputs them together with the main channel audio signals L and R, and when the Dolby pro logic signal is input, Dolby Pro Logic. Sub-channel audio signals S and C are generated by signal processing and output together with the main channel audio signals L and R. When the HD signal is input, only the main channel audio signals L and R are output as they are.

As described above, the sub-switch 208 for inputting the sub-channel audio signals S and C output from the Dolby decoder 204 is also inputted with the sub-channel audio signals SR, SL and C of the HD audio signal. As the sub-switch 208, for example, PHDAIPS TDA8440 is used. The sub-switch 208 inputs the HD sub-channel audio signals SR, SL and C and the sub-channel audio signals S and C outputted from the Dolby decoder 204, and inputs one of these sub-channel audio signals to the microcomputer 216. The subchannel audio signals SR, SL, and C are outputted according to the control of the subchannel audio signal. At this time, when the sub channel audio signal S is input from the Dolby decoder 204 to the sub switch 208, two input terminals corresponding to the sub channel audio signals SR and SL of the HD audio signal are commonly input. Therefore, when the sub switch 208 selects the output of the Dolby decoder 204, the sub channel audio signals SR and SL become S to be equal to each other. In this way, the sub channel audio signals SR and SL output from the sub switch 208 are applied to the first sub volume control unit 212, and the other sub channel audio signal C is applied to the second sub volume control unit 212. .

The microcomputer 216 used as a control unit controls the switching of the main switch 200 and the sub switch 208 according to the current reception mode, and the Dolby decoding unit 202 according to the type of input audio corresponding to the reception mode. ) To control the processing. In addition, the microcomputer 216 outputs data for adjusting the volume and tone of the main channel audio signals L and R and the volume of the sub channel audio signals SR, SL, C, and LFE. The digital-to-analog converter (hereinafter referred to as `` DAC '') 218 connected to the microcomputer 216 by the IIC bus converts the volume and tone control data output from the microcomputer 216 into an analog signal. The conversion is applied to the main volume tone control unit 210 and the first and second sub volume control units 212 and 214, respectively.

The main volume and tone control unit 210 and the first and second sub-volume control units 212 and 214 are analog controlled ICs, and the microcomputer 216 controls the DAC 218. will be. The main volume and tone control unit 210 adjusts and outputs the volume and tone of the main channel audio signals L and R output from the Dolby decoding unit 202 according to the output of the DAC 218. As the main volume and tone control unit 210, for example, Philips TDA 8425 is used. The first sub volume controller 212 adjusts and outputs the volume of the sub channel audio signals SR and SL output from the sub switch 208 according to the output of the DAC 218. In addition, the second sub volume controller 214 adjusts and outputs the volume of the sub channel audio signal C and the HD sub channel audio LFE output from the sub switch 208 according to the output of the DAC 218. As the first and second sub-volume adjusting units 212 and 214, for example, an SSM2160 manufactured by an analog device is used.

Therefore, since the main volume and tone control unit 210 and the first and second sub volume control units 212 and 214 are not directly connected to the microcomputer 216 by the bus, the area occupied on the PCB due to the bus can be reduced.

3 is a flowchart illustrating the processing of the microcomputer 216 according to an exemplary embodiment of the present invention, and illustrates a process of controlling switching of the main switch 200 and the sub switch 208 according to the four reception modes as described above. will be. Here, since the control of the Dolby decoding process and the volume and tone control are performed in the same manner as in FIG. 1 described above, the microcomputer 216 is shown only for the switching control.

Now, the audio processing operation according to the embodiment of the present invention for each of the four reception modes described above in the audio processing apparatus of FIG. 2 will be described in detail with reference to the flowchart of FIG. 3. First, when the power is turned on or the reception mode is changed, the microcomputer 216 checks the current reception mode in step 300 of FIG. 3. If the current reception mode is NTSC TV mode, the microcomputer 216 performs step 302, the DBS mode performs step 304, the external input mode performs step 306, and if it is the HD TV mode. Step 308 is performed.

In step 302, the microcomputer 216 switches the main switch 200 to NTSC L / R selection. Accordingly, the NTSC audio signal L / R is output from the main switch 200 to the Dolby decoder 204. Next, the microcomputer 216 confirms whether the pseudo surround signal processing is selected by the user in operation 310. If the pseudo surround signal processing is not selected, the Dolby decoder 204 outputs only the main channel audio signals L and R without signal processing under the control of the microcomputer 216. In this case, since the sub-channel audio signals S and C are not generated by the Dolby decoder 204, the microcomputer 216 mutes the first and second sub-volume adjusting units 212 and 214 in step 312. Accordingly, only the main channel audio signals L and R are controlled by the microcomputer 216 in the main volume and tone control unit 210 to adjust the volume and tone to be output to the speaker. Unlike the above, when the pseudo surround signal processing is selected, the Dolby decoder 204 pseudo-surrounds the main channel audio signals L and R under the control of the microcomputer 216 and generates the sub channel audio signals S and C accordingly. Output with the main channel audio signals L and R. In operation 314, the microcomputer 216 switches the sub switch 208 to the output selection of the Dolby decoding unit 202. Accordingly, the main channel audio signals L and R output from the Dolby decoder 204 are adjusted by the control of the microcomputer 216 in the main volume and tone control unit 210 to be output to the speaker and the sub-switch 208. The sub-channel audio signals SR, SL, and C outputted from the subwoofer are controlled by the microcomputer 216 in the first and second sub-volume adjusting units 212 and 214, and are output to the speaker. Therefore, NTSC audio signal L / R received from NTSC TV broadcast is processed normally.

In step 304, the microcomputer 216 switches the main switch 200 to DBS L / R selection. Accordingly, the DBS audio signal L / R is output from the main switch 200 to the Dolby decoder 204. Next, the microcomputer 216 checks whether the user selects the Dolby Pro Logic signal processing in step 310. If Dolby Pro Logic signal processing is not selected, the Dolby decoder 204 outputs only the main channel audio signals L and R without signal processing under the control of the microcomputer 216. In this case, since the sub channel audio signals S and C are not generated by the Dolby decoder 204, the microcomputer 216 performs the above operation 312. Accordingly, only the main channel audio signals L and R are controlled by the microcomputer 216 in the main volume and tone control unit 210 to adjust the volume and tone to be output to the speaker. Unlike the above, when Dolby Pro Logic signal processing is selected, the Dolby Decoder 204 processes the main channel audio signals L and R under the control of the microcomputer 216 and processes the Dolby Pro Logic signal and generates the sub channel audio signal S accordingly. , C is output with the main channel audio signals L and R. The microcomputer 216 performs step 314. The subsequent operation is the same as in the above-described NTSC TV mode. Therefore, the DBS audio signal L / R received from the DBS broadcast is normally processed.

In addition, in step 306, the microcomputer 216 switches the main switch 200 to external input L / R selection. Accordingly, the external input audio signal L / R is output from the main switch 200 to the Dolby decoder 204. Next, the microcomputer 216 confirms whether the user selects the Dolby Pro Logic signal processing in step 310, and the operation thereafter is the same as in the DBS mode. Therefore, the externally input audio signal L / R is processed normally.

In step 308, the microcomputer 216 switches the main switch 200 to HD L / R selection. Accordingly, the HD main channel audio signal L / R is output from the main switch 200 to the Dolby decoder 204. In this case, the Dolby decoder 204 outputs the main channel audio signals L and R as they are, and the main channel audio signals L and R are adjusted by the control of the microcomputer 216 in the main volume and tone control unit 210. And output to the speaker. In operation 316, the microcomputer 216 switches the sub switch 208 to the HD sub channel audio signal selection. Accordingly, the sub switch 208 outputs the HD sub channel audio signals SR, SL, and C to the first and second sub volume adjusting units 212 and 214, respectively, and the other HD sub channel audio signals LFE are the second sub volume adjusting unit. Is outputted to 214. Therefore, the HD audio signal received from the HD TV broadcast is normally processed.

Therefore, it is possible to process not only the audio signals of NTSC TV broadcasting, DBS broadcasting, and HD TV broadcasting that will be broadcast in Korea, but also analog Dolby signals coming from external inputs.

Meanwhile, in the above description of the present invention, specific embodiments have been described, but various modifications can be made without departing from the scope of the present invention. In particular, the embodiment of the present invention shows an example of processing Dolby AC-3 format audio according to HD TV broadcasting with NTSC TV broadcasting, DBS broadcasting and external input, but is required for NTSC TV broadcasting, DBS broadcasting and external input. It can be selectively applied according to In addition, an example of controlling the volume and tone by using an analog control IC is used to control the microcomputer 216 through the DAC 218. However, this is an additional adopted and is independent of processing the HD audio signal. Can be applied. Therefore, the scope of the invention should not be defined by the described embodiments, but should be defined by the equivalents of the claims and the claims.

As described above, the present invention can process audio in Dolby AC-3 format according to HD TV broadcasting, and can also process NTSC TV broadcasting, DBS broadcasting, and external input together. In addition, by adopting an analog-controlled IC, the volume and tone control unit can be controlled by the microcomputer through the DAC, thereby reducing the area occupied on the PCB.

Claims (8)

An apparatus for processing at least one NTSC TV broadcast, DBS broadcast and at least one according to the external input and multi-channel audio according to the HD TV broadcast, At least one of the NTSC TV broadcast received audio signal L / R, the DBS broadcast received audio signal L / R, and the externally input audio signal L / R; and the main channel of the HD TV broadcast received HD audio signal. A main switch which inputs an audio signal L / R, selects one of them according to a reception mode, and outputs a main channel audio signal L or R; The main channel audio signals L and R are inputted to generate sub-channel audio signals S and C from the main channel audio signals L and R when the standard signal or the Dolby Pro Logic signal is input, and the main channel audio signals L and R are output together. A Dolby decoding unit for outputting only the channel audio signals L and R as they are; The sub-channel audio signals SR, SL and C of the HD audio signals and the sub-channel audio signals S and C outputted from the Dolby decoding unit are input, and one of the sub-channel audio signals is selected to correspond to the reception mode. A sub-switch for outputting channel audio signals SR, SL, and C; The switching of the main switch and the sub-switch is controlled according to the current reception mode among NTSC TV mode, DBS mode, external input mode and HD TV mode, and the Dolby decoding according to the type of input audio corresponding to the reception mode. And a control unit for controlling negative processing. 2. The Dolby decoding unit of claim 1, wherein the Dolby decoding unit generates the sub channel audio signals S and C by pseudo surround signal processing when the standard signal is input, and the Dolby pro logic signal processing when the Dolby pro logic signal is input. A multi-channel audio processing apparatus for generating a channel audio signal S, C. The method of claim 2, wherein when the Dolby decoding unit is selected as a signal-free processing by the user when the standard signal or the Dolby Pro Logic signal is input, the main channel audio signal L without the signal processing is controlled by the controller. Multi-channel audio processing device, characterized in that the output only R. The multi-channel audio processing apparatus of claim 1, wherein the controller is a microcomputer. An apparatus for processing multi-channel audio according to NTSC TV broadcasting, DBS broadcasting, external input, and HD TV broadcasting, Input NTSC audio signal L / R, DBS audio signal L / R, external audio signal L / R, and main channel audio signal L / R of the HD audio signal according to the broadcast reception, and match one of them to the reception mode. A main switch for selecting and outputting the main channel audio signals L and R, The main channel audio signals L and R are input, and when the standard signal is input, the sub channel audio signals S and C are generated and output together by pseudo surround signal processing, and when the Dolby pro logic signal is input, the sub channel audio signals are processed by Dolby pro logic signal processing. A Dolby decoding unit for generating and outputting the channel audio signals S and C together and outputting only the main channel audio signals L and R when the HD signal is input; The sub-channel audio signals SR, SL and C of the HD audio signals and the sub-channel audio signals S and C outputted from the Dolby decoding unit are input, and one of the sub-channel audio signals is selected to correspond to the reception mode. A sub-switch for outputting channel audio signals SR, SL, and C; The switching of the main switch and the sub-switch is controlled according to the current reception mode among NTSC TV mode, DBS mode, external input mode and HD TV mode, and the Dolby decoding according to the type of input audio corresponding to the reception mode. A controller for controlling negative processing and outputting data for adjusting a volume and tone of the main channel audio signals L and R and a volume of the sub channel audio signals SR, SL, C, and LFE; A digital / analog converter for converting volume and tone control data output from the controller into an analog signal; A main volume and tone control unit for adjusting the volume and tone of the main channel audio signals L and R output from the Dolby decoding unit according to the output of the digital / analog converter; A first sub-volume adjusting unit which adjusts and outputs the volume of the sub-channel audio signals SR and SL output from the sub-switch according to the output of the digital / analog converter; And a second sub-volume control unit for adjusting and outputting a volume of the sub-channel audio signal C and the sub-channel audio LFE among the HD audio signals according to the output of the digital / analog converter. Multi Channel Audio Processor. 6. The method of claim 5, wherein the Dolby decoding unit generates the sub-channel audio signals S and C by pseudo surround signal processing when the standard signal is input, and the sub by Dolby pro logic signal processing when the Dolby pro logic signal is input. A multi-channel audio processing apparatus for generating a channel audio signal S, C. The method of claim 6, wherein when the Dolby decoding unit is selected as a signal-free processing by the user when the standard signal or the Dolby Pro Logic signal is input, the main channel audio signal L without the signal processing is controlled by the control unit. Multi-channel audio processing device, characterized in that the output only R. The multi-channel audio processing apparatus of claim 5, wherein the controller is a microcomputer.

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