JP2002074828A - Reproducer and signal selection circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reproducer which can properly reproduce various audio data. SOLUTION: A DVD reproduction part 11 reproduces the audio data of 96 kHz, etc., (sampling frequency) which are recorded on a DVD-Video disk 10. A down sampling circuit 12 converts the reproduced audio signals into those of 48 kHz (sampling frequency). When the audio signals are scrambled, the part 11 generates a detection signal and supplies it to an output selection circuit 13. Receiving the detection signal, the circuit 13 selects the audio signals of 48 kHz. When no detection signal is supplied, the reproduced audio signals of 96 kHz are selected and outputted to a receiver, etc., via a digital audio interface circuit 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reproducing apparatus for reproducing a recording medium such as a DVD, and more particularly, to appropriately reproducing various audio data having different sampling frequencies or scrambled data. And a signal selection circuit.

[0002]

2. Description of the Related Art In recent years, a DVD (Digita) capable of reproducing high-quality image data and high-quality audio data has been developed.
l Versatile Disk) players and the like are becoming widely used. This DVD player is, for example, D
It reads and reproduces digitally recorded video data and audio data from a VD-Video standard disc, and outputs clear video and audio signals to a monitor, a speaker, or the like.

[0003] DVDs to be reproduced by DVD players
Video standard discs are classified into, for example, those having a sampling frequency of 48 kHz and those having a sampling frequency of 96 kHz when classified according to the type (sound quality) of recorded audio data. Therefore, DV
The D player can reproduce audio data of these two types of sampling frequencies. When a DVD player is connected via an optical cable to a receiver (AV amplifier) or the like having a digital audio signal input terminal, the DVD player converts the reproduced audio data into a digital signal of extremely high sound quality to the receiver or the like. Can be output.

However, many commercially available receivers and the like do not support audio signals having a sampling frequency of 96 kHz. That is, 48
There are receivers and the like that can only input audio signals of kHz (sampling frequency). Therefore, a DVD player generally includes a down-sampling circuit and the like, and reproduces a reproduced 96 kHz audio signal by four.
It can down-sample to an audio signal of 8 kHz and output it.

Hereinafter, reproduction of audio data of a conventional DVD player will be described with reference to FIG. FIG.
FIG. 2 is a block diagram showing an example of a configuration (main part) of a DVD player. As shown in FIG. 4, the DVD player
VD playback unit 101 and downsampling circuit 102
, An output selection circuit 103, a digital audio interface circuit 104, and an output OFF circuit 105.
The video disc 10 and the like are reproduced.

More specifically, the DVD playback unit 101
-Read audio data from the video disc 10 and reproduce the audio signal. DVD playback unit 101
Supplies the reproduced audio signal to the downsampling circuit 102 and the output selection circuit 103. The down-sampling circuit 102 generates 96 k
When an audio signal of Hz (sampling frequency) is reproduced, it is converted into an audio signal of 48 kHz, and the converted audio signal is supplied to the output selection circuit 103.

The output selection circuit 103 selects an audio signal of any sampling frequency according to a set value that determines whether downsampling is necessary or not, and outputs the selected audio signal to the digital audio interface circuit 1.
The signal is digitally output to a receiver or the like via the device 04 or the like. That is, when the user sets a set value according to the signal input specification of the receiver or the like in the DVD player, the DVD player can output, for example, a 96 kHz audio signal to the DVD player.
It can be converted to a kHz audio signal and output, and a 96 kHz audio signal can be output as it is.

[0008]

The above-mentioned DVD player is required to have a CSS (Content Scra
96k scrambled by mbling System)
Hz audio signal cannot be output as it is (can be downsampled to 48 kHz). Therefore, the DVD player controls the digital output to be OFF in the output OFF circuit 105 shown in FIG. 4 so that the scrambled 96 kHz audio signal is not output as it is. Hereinafter, the digital output processing performed by the DVD player will be specifically described with reference to the flowchart shown in FIG.

First, the DVD player operates the DVD reproducing unit 1
01 is determined whether or not the audio signal reproduced at 01 is 96 kHz (sampling frequency) (step S1).
01). When the DVD player determines that the reproduced audio signal is not 96 kHz (48 kHz),
The output selection circuit 103 selects an audio signal that has not been downsampled (step S1).
02). The output selection circuit 103 supplies the selected 48 kHz audio signal to the output OFF circuit 105 via the digital audio interface circuit 104.
The DVD player turns on the signal output by the output OFF circuit 105 (step S103). Then, the DVD player digitally outputs the 48 kHz audio signal to a receiver or the like (step S104).

On the other hand, if it is determined in step S101 that the reproduced audio signal is 96 kHz, the DVD
The player determines whether or not downsampling is necessary according to the set value (step S1).
05). If the DVD player determines that downsampling is necessary, the downsampling circuit 102
A down-sampled 48 kHz audio signal is selected (step S106). The DVD player turns on the signal output by the output OFF circuit 105 (step S107). And the DVD player is 4
An 8 kHz audio signal is digitally output (step S108).

On the other hand, if it is determined in step S105 that downsampling is unnecessary, the DVD player determines whether or not the 96 kHz audio signal is scrambled (step S109). D
If the VD player determines that scramble has not been applied, the VD player selects an audio signal that has not been downsampled (step S110). DV
Since the audio signal is not scrambled, the D player turns on the signal output by the output OFF circuit 105 (step S111). Then, the DVD player digitally outputs the 96 kHz audio signal to a receiver or the like (step S112).

On the other hand, if it is determined in step S109 that scramble has been applied, the DVD player
OFF control is performed by the output OFF circuit 105, and the signal output is set to O.
FF is set (step S113). Therefore, the DVD player does not output an audio signal to a receiver or the like (step S114).

As described above, the DVD player controls the 96 kHz audio signal scrambled such as CSS so as not to be output as it is. In other words, if the set value of the DVD player is "downsampling unnecessary" and the user tries to reproduce the scrambled 96 kHz audio data recorded on the DVD-Video disc 10, the DVD player outputs the signal output. Since the signal is turned off, no audio signal is output to a receiver or the like. In this case, the user
DVD player converts 96kHz audio signal to 48k
It is necessary to reset the set value to “downsampling required” so that the output can be downsampled to Hz.

The change of the set value is performed, for example, by operating a remote controller or the like of a DVD player in a complicated manner, so that it is generally very troublesome for a user. For this reason, once the user resets the setting to “downsampling required”, the user returns the setting to “downsampling not required” even when reproducing another DVD-Video disc 10 that has not been scrambled. Often not. If the other DVD-Video disc 10 is reproduced with this setting value, there is no problem when reproducing 48 kHz audio data, but when reproducing 96 kHz audio data, the DVD player is unconditionally down-loaded. The sampled 48 kHz audio signal is output to a receiver or the like.

[0015] For this reason, when the receiver or the like supports the audio signal of 96 kHz, the capability of the receiver cannot be fully exhibited. In other words, when the user sets the DVD player setting value to “downsampling required”, various DVD-Video
When the disc 10 is reproduced, the DVD player
As shown in (a), digital output can be performed regardless of the presence or absence of scramble (CSS).
It will be output as an audio signal of z.

On the other hand, if the DVD player is played back with the set value of the DVD player set to “no downsampling required”, the DV
As shown in FIG. 6B, the D player can output the unscrambled 96 kHz audio signal as it is, but cannot output the scrambled 96 kHz audio signal.

That is, the conventional DVD player uses audio data having different sampling frequencies and the like,
In some cases, scrambled audio data and the like cannot be properly reproduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and has a reproducing apparatus and a signal selecting apparatus capable of appropriately reproducing various audio data having different sampling frequencies or scrambled data. It is intended to provide a circuit.

[0019]

In order to achieve the above object, a reproducing apparatus according to a first aspect of the present invention reads audio data from a predetermined recording medium and reproduces an audio signal having a first sampling frequency. Reproducing means; converting means for converting the audio signal reproduced by the reproducing means into an audio signal of a second sampling frequency; detecting that the audio signal reproduced by the reproducing means is scrambled in a predetermined manner Detecting means for selecting the audio signal of the second sampling frequency converted by the converting means when the scrambling is detected by the detecting means, and selecting the audio signal by the reproducing means when the detecting means does not detect the scrambling. Selecting the audio signal of the first sampling frequency reproduced by the Means, characterized in that it comprises an output means for outputting the audio signal selected by the selecting unit to the outside.

According to the present invention, the reproducing means includes, for example,
Audio data is read from a DVD-Video standard disc, and an audio signal having a sampling frequency of 96 kHz is reproduced. The conversion means is composed of, for example, a downsampling circuit, and converts the audio signal reproduced by the reproduction means into an audio signal having a sampling frequency of 48 kHz. The detecting means detects that the audio signal reproduced by the reproducing means is scrambled, for example, by CSS. The selection means is
When the scrambling is detected by the detecting means, an audio signal having a sampling frequency of 48 kHz converted by the converting means is selected. On the other hand, when no scrambling is detected by the detecting means, a sampling frequency of 96 kHz reproduced by the reproducing means is selected. Select an audio signal. The output unit outputs the audio signal selected by the selection unit to, for example, a receiver or the like. As described above, when the audio signal having the sampling frequency of 96 kHz is scrambled, the audio signal having the sampling frequency of 48 kHz according to the copyright protection is selected and output. When the scramble is not applied, an audio signal having a wide sampling frequency of 96 kHz is selected and output.
As a result, various audio data can be appropriately reproduced.

In order to achieve the above object, a reproducing apparatus according to a second aspect of the present invention reads out audio data from a predetermined recording medium and reproduces an audio signal of a first sampling frequency; A down-sampling circuit for down-sampling the audio signal reproduced by the reproducing unit into an audio signal of a second sampling frequency; and a generating unit for generating a detection signal indicating presence or absence of scrambling applied to the audio signal reproduced by the reproducing unit. Any one of an audio signal of a first sampling frequency reproduced by the reproducing unit and an audio signal of a second sampling frequency down-sampled by the down-sampling circuit according to the detection signal generated by the generating unit; Selection circuit for selecting audio signal Characterized by comprising a an interface circuit for outputting to the outside the audio signal in which the selection circuit selects in a predetermined interface standard.

According to the present invention, for example, the reproducing unit reads, for example, audio data from a DVD-Video standard disc and reproduces an audio signal having a sampling frequency of 96 kHz. The downsampling circuit converts the audio signal reproduced by the reproducing unit to, for example,
Down-sampling is performed to an audio signal having a sampling frequency of 48 kHz. The generating unit generates a detection signal indicating whether or not scrambling such as CSS is applied to the audio signal reproduced by the reproducing unit. The selection circuit is configured to output any one of an audio signal having a sampling frequency of 96 kHz reproduced by the reproduction section and an audio signal having a sampling frequency of 48 kHz down-sampled by the down-sampling circuit in accordance with the detection signal generated by the generation section. Select
The interface circuit outputs the audio signal selected by the selection circuit to the outside according to a predetermined interface standard.
As described above, when the audio signal having the sampling frequency of 96 kHz is scrambled, the audio signal having the sampling frequency of 48 kHz according to the copyright protection is selected and output. When the scramble is not applied, an audio signal having a wide sampling frequency of 96 kHz is selected and output. As a result, various audio data can be appropriately reproduced.

In order to achieve the above object, a signal selection circuit according to a third aspect of the present invention comprises: an acquisition unit for acquiring an audio signal of a first sampling frequency reproduced from a recording medium for recording audio data; Converting means for converting the audio signal obtained by the obtaining means into an audio signal having a second sampling frequency; detecting means for detecting that the audio signal obtained by the obtaining means has been scrambled; When the scrambling is detected by the detecting means, the audio signal of the second sampling frequency converted by the converting means is selected. When the scrambling is not detected by the detecting means, the first signal obtained by the obtaining means is obtained. Selecting means for selecting an audio signal of a sampling frequency. To.

According to the present invention, the acquiring means acquires an audio signal having a sampling frequency of 96 kHz reproduced from a DVD-Video standard disc for recording audio data. The conversion means is, for example,
It is composed of a down-sampling circuit and the like, and converts the audio signal acquired by the acquisition means into an audio signal having a sampling frequency of 48 kHz. The detecting means detects that the audio signal acquired by the acquiring means is scrambled, for example, by CSS. The selecting means selects the audio signal of the sampling frequency of 48 kHz converted by the converting means when the scrambling is detected by the detecting means, and on the other hand, when the scrambling is not detected by the detecting means,
An audio signal with a sampling frequency of Hz is selected. As described above, when the audio signal having the sampling frequency of 96 kHz is scrambled,
An audio signal having a sampling frequency of 48 kHz according to copyright protection is selected. When the scramble is not applied, an audio signal with a sampling frequency of 96 kHz in a wide band is selected. Then, since the selected audio signal is output to the outside via a predetermined interface circuit, various audio data can be appropriately reproduced.

In order to achieve the above object, a signal selection circuit according to a fourth aspect of the present invention reads out audio data from a predetermined recording medium and reproduces an audio signal of a first sampling frequency; Down-sampling means for down-sampling the audio signal reproduced by the reproducing means into an audio signal of a second sampling frequency, and generating means for generating a detection signal indicating the presence or absence of scrambling applied to the audio signal reproduced by the reproducing means An audio signal of a first sampling frequency reproduced by the reproducing means according to the detection signal generated by the generating means; and a second audio signal downsampled by the downsampling means.
And selecting means for selecting any one of the audio signals from the audio signals of the sampling frequency.

According to the present invention, the reproducing means includes, for example,
Audio data is read from a DVD-Video standard disc, and an audio signal having a sampling frequency of 96 kHz is reproduced. The downsampling means converts the audio signal reproduced by the reproducing means to, for example, 48
Downsample to an audio signal with a sampling frequency of kHz. The generating means generates a detection signal indicating the presence or absence of scrambling such as CSS applied to the audio signal reproduced by the reproducing means. The selecting means selects one of an audio signal having a sampling frequency of 96 kHz reproduced by the reproducing means and an audio signal having a sampling frequency of 48 kHz down-sampled by the down-sampling means in accordance with the detection signal generated by the generating means. Select As described above, when the audio signal having the sampling frequency of 96 kHz is scrambled,
An audio signal having a sampling frequency of 48 kHz according to copyright protection is selected. When the scramble is not applied, an audio signal with a sampling frequency of 96 kHz in a wide band is selected. Then, since the selected audio signal is output to the outside via a predetermined interface circuit, various audio data can be appropriately reproduced.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS DV according to an embodiment of the present invention
The D player will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an example of a configuration (main part) of a DVD player applied to an embodiment of the present invention. As shown, the DVD player is a DVD player.
A DVD-Video disc 10 or the like, including a playback unit 11, a downsampling circuit 12, an output selection circuit 13, and a digital audio interface circuit 14, on which audio data and the like are recorded is played back.

[0029] The DVD reproducing unit 11 is a DVD-Video.
Driving unit for rotating disk 10 and DVD-V
It is configured to include a pickup unit and the like for reading out audio data and the like recorded by irradiating a laser beam of a predetermined wavelength to the video disk 10. The DVD playback unit 11
-Read audio data having a sampling frequency of 96 kHz or 48 kHz recorded on the Video disc 10 to reproduce an audio signal. DVD playback unit 1
1 supplies the reproduced audio signal to the downsampling circuit 12 and the output selection circuit 13. DVD
The reproduction unit 11 adds a CSS (Cont.
When it is detected that scramble has been performed, such as an ent scrambling system, a signal indicating “the presence of CSS” is generated and supplied to the output selection circuit 13.

The downsampling circuit 12, for example,
A write circuit for writing data to a register in accordance with a sampling frequency of 96 kHz, a register having a predetermined capacity,
A reading circuit for reading data from the register according to a sampling frequency of 8 kHz. The down-sampling circuit 12 outputs 96
When an audio signal of kHz (sampling frequency) is reproduced, it is converted into an audio signal of 48 kHz,
The converted audio signal is supplied to the output selection circuit 13.

The output selection circuit 13 is provided with a set value for determining “automatic selection” of downsampling, etc.
According to the signal indicating “with CSS” supplied from 1
Either a 96 kHz audio signal or a 48 kHz audio signal is selected. The output selection circuit 13 supplies the selected audio signal to the digital audio interface circuit 14.

Digital audio interface circuit 1
Reference numeral 4 denotes an interface circuit or the like which defines a predetermined audio output, and outputs the audio signal selected by the output selection circuit 13 to a receiver or the like as digital audio.

Hereinafter, the operation of the DVD player according to this embodiment will be described with reference to FIG. FIG.
5 is a flowchart for explaining digital output processing performed by a VD player.

First, the DVD player operates the DVD reproducing unit 1.
It is determined whether the audio signal reproduced in step 1 is 96 kHz (sampling frequency) (step S1).
1).

If the DVD player determines that the reproduced audio signal is not 96 kHz (48 kHz), the output selection circuit 13 selects an audio signal that has not been downsampled (step S).
12). The output selection circuit 13 supplies the selected 48 kHz audio signal to the digital audio interface circuit 14.

The DVD player digitally outputs a 48 kHz audio signal to a receiver or the like via the digital audio interface circuit 14 (step S1).
3).

On the other hand, if it is determined in step S11 that the reproduced audio signal is 96 kHz, the DVD player determines whether downsampling is necessary according to the set value (step S1).
4).

When the DVD player determines that downsampling is necessary, the downsampling circuit 1
A 48 kHz audio signal downsampled in step 2 is selected (step S15). Output selection circuit 1
3 supplies the selected 48 kHz audio signal to the digital audio interface circuit 14.

The DVD player digitally outputs a 48 kHz audio signal to a receiver or the like via the digital audio interface circuit 14 (step S1).
6).

On the other hand, if it is determined in step S14 that downsampling is unnecessary, the DVD player
It is determined whether or not the 96 kHz audio signal is scrambled (step S17). If “automatic selection” is set as the set value, the DVD player determines that downsampling is not necessary.

If the DVD player determines that the audio signal has not been scrambled, it selects an audio signal that has not been downsampled (step S).
18). The output selection circuit 13 supplies the selected 96 kHz audio signal to the digital audio interface circuit 14.

The DVD player digitally outputs a 96 kHz audio signal to a receiver or the like via the digital audio interface circuit 14 (step S1).
9).

On the other hand, if it is determined in step S17 that scramble has been applied, the DVD player selects a 48 kHz audio signal down-sampled by the down-sampling circuit 12 (step S17).
20). The output selection circuit 13 supplies the selected 48 kHz audio signal to the digital audio interface circuit 14.

The DVD player digitally outputs an audio signal of 48 kHz to a receiver or the like via the digital audio interface circuit 14 (step S2).
1).

As described above, when an arbitrary DVD-Video disc 10 on which various audio data are recorded is reproduced, the DVD player can reproduce the audio signal regardless of the presence or absence of the scramble and can output the digital signal. . At this time, as shown in FIG. 3, when the audio signal having the sampling frequency of 96 kHz is scrambled, the DVD player selects the audio signal having the sampling frequency of 48 kHz according to the copyright protection and outputs the digital signal. I do. On the other hand, when the scramble has not been applied, an audio signal having a sampling frequency of 96 kHz in a wide band is selected and digitally output.

As a result, the DVD player can appropriately reproduce various audio data recorded on the DVD-Video disc 10 having different sampling frequencies or scrambled data.

In the above embodiment, only the sampling frequency is converted by the down-sampling circuit 12.
At the same time, the quantization bit length may be converted. For example, the downsampling circuit 12 has a sampling frequency of 96 k
Hz, an audio signal having a quantization bit length of 24 bits,
The audio signal may be converted into an audio signal having a sampling frequency of 48 kHz and a quantization bit length of 16 bits. Further, the numerical value of the sampling frequency and the like are merely examples, and may be appropriately changed according to a predetermined standard.

In the above embodiment, a DVD player for reproducing a DVD has been described. However, a medium to be reproduced is not limited to a DVD, and may be a CD (compact disk), an MD (mini disk) or the like. It is applicable to devices and the like. In addition, a reproducing device or the like that can reproduce a medium such as SmartMedia (trademark) or Memory Stick (trademark) may be used.

[0049]

As described above, according to the present invention,
Various audio data having different sampling frequencies or scrambled data can be appropriately reproduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of a configuration (main part) of a DVD player according to an embodiment of the present invention.

FIG. 2 is a flowchart for explaining digital output processing according to the embodiment of the present invention.

FIG. 3 is a schematic diagram showing a relationship between an audio signal selected and output in the digital output processing shown in FIG. 2 and an original audio signal.

FIG. 4 is a block diagram showing an example of a configuration (main part) of a conventional DVD player.

FIG. 5 is a flowchart illustrating a digital output process performed by a conventional DVD player.

6A and 6B are schematic diagrams showing a relationship between an audio signal selected and output in the digital output processing shown in FIG. 5 and an original audio signal.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 DVD-Video disk 11 DVD reproduction part 12 Down sampling circuit 13 Output selection circuit 14 Digital audio interface circuit

Claims (4)

[Claims] 1. A reproducing means for reading audio data from a predetermined recording medium and reproducing an audio signal having a first sampling frequency, and converting the audio signal reproduced by the reproducing means into an audio signal having a second sampling frequency. Converting means, and detecting means for detecting that a predetermined scramble has been applied to the audio signal reproduced by the reproducing means, and when the scramble is detected by the detecting means,
Selecting means for selecting the audio signal of the second sampling frequency converted by the converting means and selecting the audio signal of the first sampling frequency reproduced by the reproducing means when no scramble is detected by the detecting means; And an output unit for outputting the audio signal selected by the selection unit to the outside. 2. A reproducing unit for reading audio data from a predetermined recording medium and reproducing an audio signal of a first sampling frequency, and down-converting the audio signal reproduced by the reproducing unit to an audio signal of a second sampling frequency. A downsampling circuit for sampling, a generating unit for generating a detection signal indicating the presence or absence of scrambling applied to the audio signal reproduced by the reproducing unit; and a reproducing unit for reproducing the audio signal according to the detection signal generated by the generating unit. A selection circuit for selecting any audio signal from an audio signal of a first sampling frequency and an audio signal of a second sampling frequency down-sampled by the down-sampling circuit; and an audio signal selected by the selection circuit. Predefined interface A reproduction circuit comprising: an interface circuit that outputs to the outside in accordance with a source standard. 3. An acquiring means for acquiring an audio signal of a first sampling frequency reproduced from a recording medium for recording audio data, and converting the audio signal acquired by the acquiring means into an audio signal of a second sampling frequency. Conversion means, and detection means for detecting that predetermined scrambling has been applied to the audio signal acquired by the acquisition means, and when the scrambling is detected by the detection means,
Selecting means for selecting the audio signal of the second sampling frequency converted by the converting means, and selecting the audio signal of the first sampling frequency obtained by the obtaining means when no scramble is detected by the detecting means; A signal selection circuit, comprising: 4. A reproducing means for reading audio data from a predetermined recording medium and reproducing an audio signal of a first sampling frequency, and down-converting the audio signal reproduced by the reproducing means to an audio signal of a second sampling frequency. Down-sampling means for sampling; generating means for generating a detection signal indicating the presence or absence of scrambling applied to the audio signal reproduced by the reproducing means; and reproduction by the reproducing means according to the detection signal generated by the generating means. Signal selecting means for selecting any audio signal from an audio signal of a first sampling frequency and an audio signal of a second sampling frequency down-sampled by the down-sampling means. circuit.