JPH01258274A - Digital signal regenerating device - Google Patents

Abstract

PURPOSE:To improve the using convenience of a user and to stabilize the quality of a regenerative signal by displaying the deteriorating condition of an error rate when the error rate of a digital signal becomes under a constant value. CONSTITUTION:The regenerative signal to be obtained from a rotary head 7 is error-corrected by a decoder 12 and simultaneously, the error rate is measured by an error rate measuring circuit 19. Then, a measured result is inputted to a system control circuit 15. To the circuit 15, the minimum error rate, which can be completely error-corrected by the ability of an encoder 3 and the decoder 12, is inputted in advance and this error rate and the output of the circuit 19 are compared. Then, the deterioration of the error rate is judged. Thus, the circuit 15 executes the display of warning to a display 17 and instructs the countermeasure of cleaning, etc., before the degradation of sound quality is generated. Accordingly, the operability to the user is improved and the quality of the regenerative signal is stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a digital signal reproducing device that reproduces digital signals recorded on a recording medium.

[Prior Art] FIG. 2 shows, for example, ron The Develop
ment ofA Rotary-head Dig
ital Audio Tape Recorder
J (AES Preprint; The?9
thConventi.

n, 1985 0ctober 12-18 N
FIG. 1 is a block diagram showing a conventional digital signal reproducing device shown in EW York. In FIG. 2, a recording section is also shown.

(1) is a low-pass filter (LPF), (2) is an analog-to-digital converter, (3) is an encoder, (4) is a modulator, and (5) is an ATF (Automatic Tractor).
ck Finding) signal generator, (8) is a recording amplifier, (7) is a rotating head, (8) is a magnetic tape as a recording medium, (9) is a reproduction amplifier, (10) is a waveform equalizer and signal detection. (11) is a demodulator, (12) is a decoder, (13) is a digital-to-analog converter, (14) is a memory, (15) is a system control circuit, (till)
(17) is a display, (18) is a servo circuit, (20) is a selector switch, (21) is an audio signal input terminal for recording, and (22) is an audio signal output terminal for playback. .

Next, the operation will be explained. When recording, press the selector switch (2
0) is at the position of the solid line, and the two-channel audio signal input from the input terminal (21) is passed through the low-pass filter (1), the analog-to-digital converter (2), and the encoder (
3), the modulator (4), and the ATF signal generator (
5) is added to the ATF signal and inputted to the recording amplifier (6), and recorded on the magnetic tape (8) from the rotary head (7) via the changeover switch (20).

During playback, the changeover switch (20) is in the position indicated by the broken line, and the playback signal obtained from the rotary head (7) is passed through the changeover switch (20) to the playback amplifier (9), the waveform equalizer, and the signal detector. pass through the device (10), the demodulator (11),
Errors in the signal are corrected in a decoder (12), passed through a digital-to-analog converter (13) and a low-pass filter (1), and output as a two-channel audio signal from an output terminal (22).

Note that the memory (14) is used for interleaving and time-base compression of signals. The system control circuit (15) controls the system and displays information on the display (17) using a key human power device (16), etc., and the servo circuit (18) performs tracking control using the regenerated ATF signal. At the same time, it also controls the rotation of a reel motor and a drum motor (not shown).

[Problems to be Solved by the Invention] Since the conventional digital signal reproducing device is configured as described above, code errors can be completely corrected if the error rate of the reproduced signal is above a certain value. However, when the error rate falls below a certain value, the number of correction sounds, abnormal sounds, etc. increases, and the sound quality deteriorates.

Conventionally, there has been a problem that it is difficult for the user to understand the boundary between whether or not the error rate exceeds a certain value, making it difficult to use during playback.

This invention was made to solve the above-mentioned problems, and it is possible to predict the deterioration of sound quality due to correction sound, abnormal noise, etc. before it occurs, maintain high quality reproduction, and prevent any The purpose of the present invention is to obtain a digital signal reproducing device that can be used with peace of mind at any time.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides error rate measuring means for measuring the error rate of a reproduced digital signal;
The present invention is characterized by comprising an error rate determining means for identifying deterioration of the error rate as described in (h), and an error state display means for displaying the determination result of the error rate determining means as described in (b).

[Operations] In this invention, when the error rate of the digital signal falls below a certain value, the error rate determination means determines whether the error rate has deteriorated, and the error state display means displays the deterioration state of the error rate. The user can easily know the status of the device by looking at this display, improving usability.
The quality of the reproduced signal becomes stable.

[Example] Hereinafter, an example of the present invention will be described with reference to FIG.

In FIG. 1, an error rate measuring circuit (19) is provided between a decoder (12) and a system control circuit (15). Since the other configurations are the same as those in FIG. 2, the same parts are given the same reference numerals and repeated explanation will be omitted. In addition,
The error rate measuring circuit (19) is error rate measuring means, and the system control circuit (15) is error rate determining means.

The displays (17) each constitute error status display means.

Next, the operation will be explained. Rotating head (7) during playback
The reproduced signal obtained from the A circuit (18) measures the error rate and inputs the result to a system control circuit (15). System control circuit (15
) is input in advance with the minimum error rate that can be completely corrected by the capabilities of the encoder (3) and decoder (12), and this is compared with the output of the error rate measurement circuit (19). do. As a result of the comparison, if it is determined that the error rate is below a certain value, that is, the error rate has worsened, the system control circuit (15
) displays a warning on the display (17) and instructs the user to take measures such as cleaning before the sound quality deteriorates.

Note that in the above embodiments, a device capable of recording and reproducing was described, but a recording section is not necessarily necessary, and
The reproduced signal is not limited to an audio signal, but may also be a video signal, and in this case, the same effects as in the above embodiment can be achieved.

Furthermore, in the above embodiments, an apparatus using a rotating head has been described, but an apparatus using a fixed head may be used, and the type of the head does not matter.

Further, in the above embodiments, an apparatus using a magnetic tape as a recording medium has been described, but it goes without saying that any recording medium other than magnetic tape, including a magnetic disk, can be used as the recording medium.

7 Effects of the Invention] As described above, according to the present invention, there are provided an error rate measuring means for measuring the error rate of a reproduced digital signal, an error rate determining means for identifying deterioration of the error rate, and an error rate determining means. By providing an error status display means for displaying the results of the error status, the user can easily know the error status, it is easy to use, and it is easy to maintain an appropriate error rate, so the quality of the reproduced signal is stabilized. There is an effect.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a digital signal reproducing apparatus according to the present invention, and FIG. 2 is a block diagram showing a conventional digital signal reproducing apparatus. (8)...Magnetic tape, (15)...System control circuit, (17)...Display, (19)...
Wrong book measurement circuit. In addition, in FIG. 1, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] (1) In an apparatus for reproducing a digital signal recorded on a recording medium, an error rate measuring means for measuring an error rate of the reproduced digital signal, an error rate determining means for identifying a deterioration of the error rate, and an error rate determining means for determining the deterioration of the error rate; A digital signal reproducing device comprising error status display means for displaying the determination result of the rate determination means.