KR100280789B1 - AC-3 two channel output device and method of optical disc player - Google Patents

Abstract

The AC-3 two-channel output device and method of the disclosed optical disc reproducing apparatus utilizes a digital / analog converter that combines a pulse code modulation data reproducing function and a bass speaker data reproducing function to reduce the digital / analog converter. A two-channel output device and method.

The present invention provides an A / V decoder for decoding and outputting an audio and video signal applied from the outside; A first DAC receiving audio data “0” output from the A / V decoder and converting the analog data into analog data; A first LPF for removing quantization noise of analog data output from the first DAC; A second switch for selecting one of an “A” terminal for switching audio data “0” output from an A / V decoder and a “B” terminal for switching audio data “1” according to an external switching control; A second DAC receiving audio data “0” or “1” output from the A / V decoder through a second switch and converting the analog data into analog data; A second LPF for removing quantization noise of analog data output from the second DAC; A third switch for switching on and off the audio signal output from the second LPF; A third LPF for removing quantization noise of analog data output from the third switch; A first switch for selecting one of an “A” terminal for switching the first LPF output signal and a “B” terminal for switching the second LPF output signal according to an external switching control; A controller for outputting a switching control signal for controlling switching of the first switch, the second switch, and the third switch; A summer for adding up the analog signal output from the first switch and the analog signal output from the third LPF; An amplifier for amplifying the summed analog signal through a summer; It consists of a two-channel output that outputs the audio signal amplified through the amplifier to L, R two channels to the outside.

Accordingly, the present invention utilizes a digital / analog converter that combines a pulse code modulation data reproducing function and a bass speaker data reproducing function, thereby reducing the number of expensive digital / analog converters, thereby reducing the cost of the product.

Description

AC-3 two channel output device and method of optical disc player

The present invention relates to an AC-3 two-channel output device and method of an optical disc reproducing apparatus, and more particularly, to a digital / analog converter that combines a pulse code modulation (PCM) data reproducing function and a subwoofer (SUB-WOOFER) data reproducing function. The present invention relates to an AC-3 two-channel output device and method for an optical disk reproducing apparatus, which has reduced the number of digital-to-analog converters by using a s.

In general, an optical disc such as a CD (Compact Disc), LD (Laser Disk), or DVD (Digital Versatile Disk) is produced so that data such as audio or video can be recorded in a predetermined effective area and reproduced using an optical disc reproducing apparatus In addition to being a solid storage medium, recorded data is not easily damaged by external factors such as temperature and humidity.

In addition, an optical disc player such as a VCDP (Video Compact Disc Player) or a DVDP (Digital Versatile Disc Player) can reproduce data recorded on an optical disc without noise by using a laser in the optical pickup unit under the control of a controller. Its use is gradually increasing.

In addition, when outputting audio signals from a DVD player, there are two cases in which only two channels are used and an AC-3 5.1 channel is used. That is, in the above description, two channels mean two channels (speakers) of a front L (left) channel and an R (right) channel.

In addition, the above 5.1 channel is the sum of two channels of the front L channel and the R channel, the rear L and R channels, the three channels of the center channel and the 0.1 channels of the subwoofer (SUB-WOOFER) channel. This means AC-3, “Dolby Digital” system.

In the above, AC-3 stands for AUDIO COMPRESSION, which means “digital voice compression technology.” When you listen to audio with 5.1 channel speaker of AC-3, it reproduces fine sound that you could not hear on CD. You can enjoy sound quality.

Therefore, only two channels are output in stereo when the optical discs of CD and VCD are reproduced, and 5.1 channels of AC-3 are output when the optical disc of DVD is reproduced. However, when only two channels of DVD are used, the rear L and R channels, the center channel, and the subwoofer channel are mixed with the front L and R channels (two channels) and output.

1 is a block diagram of an AC-3 two-channel output device of a conventional optical disc player.

A / V decoder 11 decoded into an audio and video signal, and a first DAC (digital / analog) capable of receiving audio data “0” output from the A / V decoder 11 and sampling up to 48 KHz in 20-bit data. A converter: hereinafter referred to as a DAC 12, a first LPF (hereinafter referred to as LPF) 13 for removing quantization noise of data output from the first DAC 12, and the A / V decoder 11 The second DAC 14, which is supplied with audio data “0” outputted from the PDP, and has a built-in PLL function and is capable of sampling up to 96 KHz in 24-bit data and a quantization noise of the data output from the second DAC 14; 2LPF 15, a third DAC 16 that receives audio data “1” output from the A / V decoder 11, and converts a digital subwoofer signal into an analog signal, and a third DAC 16; A third LPF 17 and a fourth LPF 18 for removing quantization noise of data output from the first LPF 17 and the first LPF 13; The first switch 19 for selecting one of the second LPF 15, the control unit 23 for controlling the first switch 19, the analog signal output from the first switch 19 and the fourth LPF 18 And a two-channel output unit 22 for outputting the amplified audio signal.

The PLL is an abbreviation of Page Lock Loop and means a loop circuit that tracks a specific frequency. The second DAC 14, which has a built-in PLL function and can sample up to 96 KHz in 24-bit data, has a lower performance than that of the first DAC 12, but the first DAC 12 and the second DAC 14 for improved audio performance. I'm using two of them.

However, the use of expensive DACs, compared to 5.1 channels rather than 5.1 channels, has a problem of increasing the unit price of the product.

Accordingly, an object of the present invention is to provide an AC-3 two-channel output device and method for an optical disk reproducing apparatus, which utilizes a digital / analog converter that combines a pulse code modulation data reproduction function and a bass speaker data reproduction function. To provide.

1 is a block diagram of an AC-3 two-channel output device of a conventional optical disc player.

2 is a block diagram of an AC-3 two-channel output device of the optical disk reproducing apparatus of the present invention.

3 is a flow chart related to the audio output method of a CD / VCD optical disc in the AC-3 two-channel output of the present invention.

4 is a flowchart showing a sound output method of a DVD optical disc in the AC-3 two-channel output of the present invention.

* Explanation of symbols for main parts of the drawings

51: A / V Decoder 52: First DAC

53: first LPF 54: second DAC

55: second LPF 56: first switch

57: second switch 58: third switch

59: control unit 60: third LPF

61: summer 62: amplifier

63: 2 channel output

AC-3 two-channel output device of the optical disk playback apparatus according to the present invention for achieving this object comprises an A / V decoder for decoding and outputting audio and video signals applied from the outside; A first DAC receiving audio data “0” output from the A / V decoder and converting the analog data into analog data; A first LPF for removing quantization noise of analog data output from the first DAC; A second switch for selecting one of an “A” terminal for switching audio data “0” output from an A / V decoder and a “B” terminal for switching audio data “1” according to an external switching control; A second DAC receiving audio data “0” or “1” output from the A / V decoder through a second switch and converting the analog data into analog data; A second LPF for removing quantization noise of analog data output from the second DAC; A third switch for switching on and off the audio signal output from the second LPF; A third LPF for removing quantization noise of analog data output from the third switch; A first switch for selecting one of an “A” terminal for switching the first LPF output signal and a “B” terminal for switching the second LPF output signal according to an external switching control; A controller for outputting a switching control signal for controlling switching of the first switch, the second switch, and the third switch; A summer for adding up the analog signal output from the first switch and the analog signal output from the third LPF; An amplifier for amplifying the summed analog signal through a summer; It characterized in that it comprises a two-channel output unit for outputting the audio signal amplified by the amplifier to the two channels of L, R to the outside.

In addition, the AC-3 two-channel output method of the optical disc playback apparatus according to the present invention is the audio output method for outputting to the AC-3 (Audio Compression-3) two channels of CD and VCD optical discs. A first step of outputting audio data from the A / V decoder; A second step of converting audio digital data output from the A / V decoder into an analog signal by a first DAC and filtering quantization noise through a first LPF; A third step of amplifying the filtered audio signal through an amplifier by connecting to the “A” terminal of the first switch by switching control of the controller; And a fourth step of outputting the analog signal amplified by the amplifier to the outside through a two-channel output device.

The AC-3 two-channel output method of the optical disc reproducing apparatus according to the present invention is an audio output method of outputting two channels of AC-3 (Audio Compression-3) of a DVD optical disc. A tenth step of outputting 5.1 channel audio data from the A / V decoder; An eleventh step of converting audio data “0” of the 5.0 channel output from the A / V decoder into an analog signal through a first DAC, and filtering quantization noise through a first LPF; A twelfth step of connecting the filtered audio signal to the “A” terminal of the first switch by a switching control of the controller and outputting the filtered audio signal to an adder; The audio data “1” of the 0.1 channel (subwoofer channel) output from the A / V decoder is connected to the “B” terminal of the second switch by switching control of the controller, and converted into an analog signal through the second DAC. A thirteenth step of filtering quantization noise through 2LPF; A fourteenth step of filtering the audio signal filtered through the second LPF once more by operating the third switch ON by the control of the controller; A fifteenth step of adding the audio signal of the 0.1 channel filtered through the fourteenth step with the audio signal of which 5.0 channels are compressed; Amplifying the summed audio signal, and characterized in that it comprises a sixteenth step of outputting to the outside through a two-channel output.

Hereinafter, a configuration and an embodiment of the present invention will be described with reference to the accompanying drawings.

2 is a block diagram of an AC-3 two-channel output device of the optical disc reproducing apparatus of the present invention.

As shown, the A / V decoder 51 decodes the audio and video signals applied from the outside and outputs them to the first DAC 52 or the second DAC 54 which will be described later.

The first DAC 52 receives audio data “0” output from the A / V decoder 51 and converts the analog data into analog data. At this time, the first DAC 52 can sample up to 48KHz on 20-bit data.

The first LPF 53 removes quantization noise of the analog data output from the first DAC 52.

The second switch 57 selects one of audio data “0” terminals and audio data “1” terminals output from the A / V decoder 51 according to the switching control of the controller 59 to be described later.

The second DAC 54 receives audio data “0” or “1” output from the A / V decoder 51 through the second switch 57, and converts the analog data into analog data. At this time, the second DAC 54 can sample up to 96KHz in 24-bit data.

The second LPF 55 and the third LPF 60 remove quantization noise of the analog data output from the second DAC 54.

The third switch 58 transfers the signal output from the second LPF 55 to the third LPF 60 by the on-off action according to the switching control of the controller 59 to be described later.

The first switch 56 selects one of the first LPF 53 output signal and the second LPF 55 output signal according to the switching control of the controller 59 to be described later and outputs the same to the summer 61.

The controller 59 may provide a switching control signal for controlling the switching of the first switch 56, the second switch 57, and the third switch 60 to the corresponding first switch 56, the second switch 57, and the like. Output to each of the third switch (60).

The summer 61 adds the analog signal output from the first switch 56 and the analog signal output from the third LPF 60 and outputs the same to the amplifier 62.

The amplifier 62 amplifies the analog signal output from the first switch 56, which is added up through the summer 61, and the analog signal output from the third LPF 60 to externally through the two-channel output device 63. Outputs the amplified audio signal.

The operation principle of the AC-3 two-channel output device of the optical disk reproducing apparatus configured as described above will be described according to the flowchart.

First, the operation of the audio output method of the CD / VCD optical disc in the AC-3 two-channel output of the present invention will be described with reference to FIG.

First, when a user wants to listen to a voice signal by playing a CD and / or VCD optical disc, the PCM reproducing apparatus is operated to output audio data from the A / V decoder 51 (S31), and the A / V decoder 51 After the audio data output from the first signal is converted into an analog signal by the first DAC 52, the quantization noise is filtered by the first LPF 53 (S32).

Thereafter, the filtered audio signal is connected to the “A” terminal by the first switch 56 under the control of the controller 59, and the filtered audio signal is amplified through the amplifier 62 (S33). It is output to the outside by the output device 63 (S34).

That is, the first DAC 52 utilizes the principle that not only an AC-3 audio digital signal but also a PCM (pulse code modulation) audio digital signal can be converted into an analog signal and reproduced.

Next, in addition to the audio output method of the CD / VCD optical disc of FIG. 3 described above, FIG. 4 shows an operation process of the audio output method of the DVD optical disc at the time of AC-3 two channel output.

First, when a user wants to listen to an audio signal by playing a DVD optical disc, the AC-3 reproducing apparatus is operated to output 5.1 channel audio data from the A / V decoder 51 (S41), and the A / V decoder ( The audio data “0” output from 51 is converted into an analog signal by the first DAC 52 and then quantized noise is filtered by the first LPF 53 (S42).

Here, the audio data output from the A / V decoder 51 outputs 5.1 channels of AC-3, so that the 5.0 channels are mixed with the L, R channels and the center channel of the rear to the L and R channels (2 channels) of the front panel. Is output. Therefore, the 5.0 channel transmits audio data to the first DAC 52 and the 0.1 channel transmits audio data to the second DAC 54.

After the quantization noise is filtered by the first LPF 53, the audio signal is output to the summer 61 through the “A” terminal of the first switch 56 under the control of the controller 59 (S43). ).

In addition, the 0.1 channel is a subwoofer channel and the audio data “1” output from the A / V decoder 51 is connected to the “B” terminal of the second switch 57 controlled by the controller 59 (S44). After conversion to the analog signal by the second DAC 54, the quantum and noise are filtered by the second LPF 55 (S45).

After the third switch 58 is turned on under the control of the controller 59, the audio signal filtered by the second LPF 55 is once again filtered by the third LPF 60 ( S46).

As described above, the 0.1-channel audio signal filtered once by the third LPF 60 is summed with the audio signal of which 5.0 channels are compressed by the summer 61 through the above-described step S43 (S47). The output signal is amplified by 62) and output to the outside through the two-channel output device 63 to the L and R two channels (S48).

That is, the second DAC 54 utilizes the principle that AC-3 data is not reproduced, only PCM data is reproduced, and subwoofer data can be reproduced.

The present invention constructed and functioning as described above utilizes a digital / analog converter that combines a pulse code modulation data reproducing function and a bass speaker data reproducing function, thereby reducing the number of expensive digital / analog converters and lowering the unit cost of the product. Has an effect.

Claims (5)

An audio output device for outputting two AC-3 (Audio compression-3) channels of an optical disc reproducing apparatus, comprising: an A / V decoder for decoding and outputting audio and video signals applied from the outside; A first DAC receiving audio data “0” output from the A / V decoder and converting the analog data into analog data; A first LPF that removes quantization noise of analog data output from the first DAC; A second switch for selecting one of an “A” terminal for switching audio data “0” output from the A / V decoder and a “B” terminal for switching audio data “1” according to an external switching control; A second DAC receiving audio data “0” or “1” output from the A / V decoder through the second switch and converting the analog data into analog data; A second LPF for removing quantization noise of the analog data output from the second DAC; A third switch for switching on and off the audio signal output from the second LPF; A third LPF for removing quantization noise of analog data output from the third switch; A first switch for selecting one of an “A” terminal for switching the first LPF output signal and a “B” terminal for switching a second LPF output signal according to an external switching control; A controller for outputting a switching control signal for controlling switching of the first switch, the second switch, and the third switch; A summer for adding up the analog signal output from the first switch and the analog signal output from a third LPF; An amplifier for amplifying the summed analog signal through the summer; And a two-channel output unit for outputting the audio signal amplified by the amplifier to two channels of L and R to the outside. The method of claim 1, wherein the first DAC; An AC-3 two-channel output device of an optical disc reproducing apparatus, wherein not only an AC-3 digital signal but also a PCM (pulse code modulation) digital signal is converted into an analog signal and reproduced. The method of claim 1, wherein the second DAC; An AC-3 two-channel output device of an optical disc reproducing apparatus, wherein only a PCM digital signal and a SUB-WOOFER digital signal are converted into analog signals and reproduced. An audio output method for outputting two channels of AC-3 (Audio Compression-3) of CD and VCD optical discs, comprising: a first step of operating a PCM reproducing apparatus to output audio data from an A / V decoder; A second step of converting audio digital data output from the A / V decoder into an analog signal by a first DAC and filtering quantization noise through a first LPF; A third step of amplifying the filtered audio signal through an amplifier by connecting to the “A” terminal of the first switch by switching control of a controller; And a fourth step of outputting the analog signal amplified by the amplifier to the outside through a two-channel output device. An audio output method for outputting two channels of AC-3 (Audio Compression-3) of a DVD optical disc, comprising: a tenth step of operating an AC-3 reproducing apparatus to output 5.1 channel audio data from an A / V decoder; An eleventh step of converting audio data “0” of the 5.0 channel output from the A / V decoder into an analog signal through a first DAC, and filtering quantization noise through a first LPF; A twelfth step of connecting the filtered audio signal to an “A” terminal of a first switch by a switching control of a controller to output to a summer; The audio data “1” of the 0.1 channel (subwoofer channel) output from the A / V decoder is connected to the “B” terminal of the second switch by switching control of the controller, and converted into an analog signal through the second DAC. A thirteenth step of filtering quantization noise through a second LPF; A fourteenth step of filtering the audio signal filtered through the second LPF once more by operating the third switch ON by the switching control of the controller; A fifteenth step of adding the audio signal of the 0.1 channel filtered through the fourteenth step with the audio signal of which the 5.0 channel is compressed; And a sixteenth step of amplifying the summed audio signal and then outputting the result to the outside through a two-channel output device.

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