KR100724204B1 - Apparatus for reproducing a data on recorded optical disc - Google Patents

Abstract

The present invention relates to an optical disc reproducing apparatus, comprising: MP3 audio data in order to read and reproduce the MP3 audio data from an optical disc in which audio data in a general CD format, audio data in a high density CD format, and MP3 audio data are mixed and recorded. An attenuation resistor for attenuating or selectively blocking an external clock of a predetermined frequency so that a decoding operation of the MP3 audio data by the internal clock is normally performed in addition to a separate internal clock generator required for the decoding operation; By installing and using the switching transistor, it is a very useful invention that it is possible to normally perform the reproduction operation of the audio data in the general CD format, the audio data in the high density CD format, and the MP3 audio data.

MP3 audio data, sampling rate, internal clock, external clock, attenuation resistor, switching transistor

Description

Optical disc player {Apparatus for reproducing a data on recorded optical disc}             

1 shows a configuration of a general optical disc player,

2 shows a configuration of an optical disk reproducing apparatus according to the present invention,

3 shows signal levels of an internal clock and an external clock applied to the decoding module of the optical disc reproducing apparatus according to the present invention.

4 shows the configuration of another embodiment of the optical disc reproducing apparatus according to the present invention.

※ Explanation of code for main part of drawing

10: optical disc 11: optical pickup

12: RF signal processor 13: digital signal processor

14,24: decoder 15: D / A converter

16: external clock generator 17: microcomputer

141,241: sampling rate detector 142,242: decoding module

243: internal clock generator

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc reproducing apparatus, and more particularly, to reproduce playback data read from an optical disc on which various types of data having different sampling rates are recorded, and selecting a clock having an appropriate frequency. An optical disc reproducing apparatus for performing a decoding operation.

First, FIG. 1 shows a configuration of a general optical disc reproducing apparatus, wherein the optical disc reproducing apparatus includes: an optical pickup 11 for reading a signal recorded on an optical disc 10 such as a CD as a high frequency signal; An RF signal processor 12 for converting the read high frequency signal into binary data; A digital signal processor (13) for signal-processing the converted binary data into a digital reproduction signal; A decoder unit (14) comprising a sampling detector (141) for detecting a sampling rate of the digital reproduction signal, and a decoding module (142) for selectively decoding the digital reproduction signal according to the detected sampling rate; A D / A converter 15 for converting and outputting a digital reproduction signal output from the decoder into an analog reproduction signal; And an external clock generator 16 generating an external clock of a predetermined frequency necessary for the decoding operation and the D / A conversion operation.

Meanwhile, in the optical disc 10, audio data of a general CD (CD) format and audio data of a high density CD (HDCD: High Density CD) format may be mixed and recorded, and a sampling rate detector configured to be included in the decoder unit. In 141, the digital reproduction signal signal-processed by the digital signal processing unit 13, that is, the header information of the digital data is searched and read, and the sampling rate of the digital data is detected.

In addition, in the decoding module 142, when the detected sampling rate has a value corresponding to audio data of a general CD (CD) format, the D / A conversion unit ( 15), and when the detected sampling rate corresponds to audio data in a high density CD (HDCD) format, a clock of a predetermined frequency generated from the external clock generator 16, for example, 44.1 KHz After the decoding operation of decoding the audio data of the high-density CD format using an external clock of the outputted to the D / A converter 15.

The D / A converter 15 converts the digital data output from the decoder 14 into an analog signal using an external clock of 44.1 KHz generated from the external clock generator 16. Done.

Therefore, even when audio data in a general CD (CD) format and audio data in a high density CD (HDCD) format having different sampling rates are mixed and recorded on the optical disc 10, sampling of reproduction data as described above is performed. After detecting the rate, by selectively performing a decoding operation, a normal audio reproduction operation can be performed.

However, MP3 audio data, which has recently been spread and spread, can be additionally recorded on an optical disc in which audio data of the general CD format and audio data of a high density CD format are mixed and recorded. In order to decode the MP3 audio data, In addition to the external clock of 44.1KHz, a clock of another frequency is necessary, so a solution for this is urgently needed.

Accordingly, the present invention has been made in view of the above circumstances, and in order to read out and reproduce the MP3 audio data from an optical disc in which audio data in a general CD format, audio data in a high density CD format, and MP3 audio data are mixed and recorded. Another object of the present invention is to provide an optical disc reproducing apparatus including a separate internal clock generator required for decoding the MP3 audio data and to decode the MP3 audio data by the internal clock.

An optical disc reproducing apparatus according to the present invention for achieving the above object comprises: first clock generating means for generating a clock signal in accordance with a type of input data; Second clock generating means for generating a clock signal regardless of the type of input data; Attenuating means for attenuating a clock signal from said second clock generating means for generating a clock signal required for decoding said input data; And data decoding means for decoding the input data into a clock signal in which the output from the first clock generating means and the output from the attenuation means are mixed according to the type of the input data. ,

In addition, an optical disc reproducing apparatus according to the present invention comprises: first clock generating means for generating a clock signal in accordance with a type of input data; Second clock signal generation means for generating a clock signal regardless of the type of input data; Switching means for selective output of a clock signal from said second clock generating means for generating a clock signal required for decoding said input data; And data decoding means for decoding the input data into a clock signal in which the output from the first clock generating means and the output from the attenuation means are mixed according to the type of the input data.

Hereinafter, a preferred embodiment of an optical disc reproducing apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

First, FIG. 2 illustrates a configuration of an embodiment of an optical disc reproducing apparatus according to the present invention. In the optical disc reproducing apparatus, as described above with reference to FIG. 1, the optical pickup 11 and the RF signal processing unit 12 are described. And an external clock generator 16 for generating an external clock of 44.1 kHz with the digital signal processor 13, the D / A converter 15, and the digital signal processor 13 for signal processing. In accordance with a sampling detector 241 for detecting a sampling rate of the digital reproduction signal, a decoding module 242 for selectively decoding the digital reproduction signal in accordance with the detected sampling rate, and in accordance with the detected sampling rate, The MP3 decoder unit 24 including the internal clock generator 243 for selectively generating an internal clock of an arbitrary frequency may be included.

Meanwhile, the MP3 decoder 24 may be manufactured by a single physical chip, and as illustrated in FIG. 2, an external clock of 44.1 KHz generated from the external clock generator 16 may be generated. And an external clock input port for applying to the decoding module 242, and an attenuation for attenuating a signal level of an external clock applied to the decoding module 242 outside the external clock input port. The resistor R may be installed.

Therefore, the sampling rate detection unit 241 searches for and reads the digital reproduction signal processed by the digital signal processing unit 13, that is, the header information of the digital data, to detect the sampling rate of the digital data. In the decoding module 242, when the detected sampling rate has a value corresponding to audio data of a general CD (CD) format, the D / A conversion unit ( 15), and when the detected sampling rate corresponds to high-density CD (HDCD) format audio data, a high-density CD is generated by using an external clock of 44.1 KHz generated from the external clock generator 16. After performing a decoding operation for decoding the audio data of the format, it is output to the D / A converter 15.

The D / A converter 15 converts the digital data output from the decoder 14 into an analog signal using an external clock of 44.1 KHz generated from the external clock generator 16. Done.

On the other hand, when the sampling rate detected by the sampling rate detector 241 has a value corresponding to the MP3 audio data, the internal clock generator 243 is used for the sampling rate output from the sampling rate detector 241. Accordingly, an internal clock CLK_I of an arbitrary frequency corresponding thereto is generated.

That is, the internal clock generator 243 selectively generates an internal clock of 32 KHz, 44.1 KHz, or 48 KHz to decode MP3 audio data having different sampling rates. The internal clock generator 243 When an internal clock of 32 KHz is generated, the 32 KHz internal clock and an external clock of 44.1 KHZ are simultaneously applied to the decoding module 242.

However, since the signal level of the 44.1 KHz external clock CLK_E is attenuated and applied by the attenuation resistor R, as shown in FIG. 3, the signal level is relative in the decoding module 242. By using the high internal clock of 32 KHz, the MP3 audio data can be decoded normally.

For reference, when the signal level of the external clock is not attenuated using the attenuation resistor R as described above, the decoding module 242 is abnormal due to the internal clock of 32 KHz and the external clock of 44.1 KHz applied simultaneously. Decoding operation is performed.

Meanwhile, as another embodiment of the optical disc reproducing apparatus according to the present invention, as shown in FIG. 4, the microcomputer (not shown) replaces the attenuation resistor R with the switching transistor TR and is included in the optical disc reproducing apparatus. In 17), the switching transistor may be turned on / off based on the sampling rate output from the sampling rate detector 241.

Accordingly, when the sampling rate detected by the sampling rate detector 241 has a value corresponding to the MP3 audio data, as described above with reference to FIG. 2, the internal clock generator 243 performs the sampling. According to the sampling rate output from the rate detector 241, an internal clock CLK_I of an arbitrary frequency corresponding thereto is generated. In the microcomputer 17, the switching transistor is turned on to decode the decoder. The external clock of 44.1 KHz applied to the module 242 is blocked.

Therefore, since only the 32 kHz internal clock generated from the internal clock generator 243 is applied to the decoding module 242, the MP3 audio data can be decoded normally.

On the other hand, when the sampling rate detected by the sampling rate detection unit 241 is audio data in a general CD format or audio data in a high density CD format, the switching transistor is turned off to provide an external clock of 44.1 KHz. In this case, the decoding module 242 is applied to the decoding module 242 to selectively perform the normal decoding operation by the external clock.

As described above, preferred embodiments of the present invention are disclosed for purposes of illustration, and those skilled in the art can improve various other embodiments within the spirit and technical scope of the present invention disclosed in the appended claims below. Modifications, substitutions or additions may be made.

The optical disc reproducing apparatus according to the present invention configured as described above includes a MP3 for reading and reproducing the MP3 audio data from an optical disc in which audio data in a general CD format, audio data in a high density CD format, and MP3 audio data are mixed and recorded. In addition to a separate internal clock generator for decoding the audio data, and to attenuate or selectively block the external clock of a predetermined frequency so that the decoding operation of the MP3 audio data by the internal clock is normally performed By installing and using attenuation resistors or switching transistors, it is a very useful invention that it is possible to normally perform reproduction operations of MP3 audio data as well as audio data of general CD format and high density CD format.

Claims (4)

First clock generating means for generating a clock signal in accordance with the type of input data; Second clock generating means for generating a clock signal regardless of the type of input data; Attenuating means for attenuating a clock signal from said second clock generating means for generating a clock signal required for decoding said input data; And And a data decoding means for decoding the input data as a clock signal in which the output from the first clock generating means and the output from the attenuation means are mixed according to the type of the input data. Playback device. The method of claim 1, The type of the input data is determined according to a sampling frequency. The method of claim 1, And said attenuation means is a resistor having a specific value. First clock generating means for generating a clock signal in accordance with the type of input data; Second clock signal generation means for generating a clock signal regardless of the type of input data; Switching means for selective output of a clock signal from said second clock generating means for generating a clock signal required for decoding said input data; And And data decoding means for decoding the input data into a clock signal in which the output from the first clock generation means and the output from the attenuation means are mixed according to the type of the input data. Device.

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