JP2629707B2 - Audio recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a recording medium having a plurality of tracks in which a plurality of sectors can be set. The present invention relates to an audio recording device which records a control code indicating an axial compression ratio and flags indicating the start, continuation and end of the audio signal.

[Conventional technology]

FIG. 3 is a block diagram showing a configuration of a conventional recording apparatus for recording an audio signal on a disk-shaped recording medium, and FIG. 4 is an operation flow chart thereof. Prior to recording on the disk 11, the time axis compression ratio of the audio signal is set to the CPU 10 manually or adaptively by a circuit (S1). When the recording start is instructed from the switch 12, the CPU 10 sends a control signal of the memory control circuit 14, and the memory control circuit 14 sets the sampling clock and the address to A / A at a cycle corresponding to the compression ratio.
It is supplied to the D converter 16 and the memory 18. Thus, the input audio signal is temporarily stored (frozen) in the memory 18 (S2). When a certain amount of signals are stored in the memory 18, the CPU 1
0 outputs a track feed signal to the mechanism control circuit 20, and the mechanism control circuit 20 positions the magnetic head 22 on a recordable track by a head feed mechanism (not shown) (S3).

Since a predetermined flag and a control code are added to the audio data for recording, the CPU 10 applies a set signal for this to the memory control circuit 14.
However, the content of the flag and the control code to be recorded at the same time differs between when the recording end instruction is input from the switch 12 to the CPU 10 and when it is not input, that is, when recording continuation is instructed. So CPU10
Checks the switch 12 and outputs a corresponding set signal to the memory control circuit 14 (S4, 5, 6).

The memory control circuit 14 outputs an address signal to the memory 18 in synchronization with the rotation of the disk 11 under an instruction from the CPU 10, and the memory 18 outputs audio data to one contact of the switch 24. A flag and a control code are input from the memory control circuit 14 to the other contact of the switch 24. The memory control circuit 14 switches the switch 24 according to the rotation of the disk 11. As a result, D /
The A converter 26 is supplied with audio data to which a flag and a control code have been added. The output of the D / A converter 26 is FM-modulated by the FM modulator 28 and recorded on the disk 11 by the magnetic head 22 (S7, 8).

When recording audio on the next track, the audio signal is frozen again in the memory 18 (S2), and the same operation as described above is repeated. When recording is completed on this track, the process ends here. .

Note that an audio signal continuously recorded using a plurality of tracks is called a sequence. In one sequence,
The time axis compression ratio cannot be changed. One track is divided into four sectors, and the usage status of each sector is represented by the polarity of two flags, a start flag and an end flag. In other words, it is possible to determine from these flags whether recording is continued to the next sector in the track, whether the track ends and the head sector of the next track is continued, or whether it is unused. A control code is recorded in each sector. The control code includes the current track number, the first track number in the sequence,
The next track number, the track number of the video corresponding to this track, and the time axis compression ratio are included. There are three types of compression rates, 1/320, 1/640, and 1/1280, and the maximum recording time per track is about 5 seconds, about 10 seconds, and about 20 seconds, respectively.

[Problems to be solved by the invention]

In the above conventional example, it is impossible to change the compression ratio in the middle of the sequence. In order to change the compression ratio, it is necessary to end the sequence once and start recording as another sequence. The sequence end and sequence start tracks must record corresponding flags and control codes, respectively.

As described above, in the method of once stopping the recording and then restarting the recording, continuous sound is recorded without interruption. In particular, when there is only one remaining track on the disk 11 during continuous recording, even if it is found that the end of the audio cannot be recorded because it slightly exceeds the scheduled time, the compression rate is switched and recorded. The time could not be increased, and it was necessary to re-record from the beginning, which was extremely inconvenient.

Accordingly, it is an object of the present invention to provide an audio recording apparatus capable of changing the time axis compression ratio and recording in the middle without interrupting the audio when the audio signal is compressed on the time axis and recorded continuously.

[Means for solving the problem]

An audio recording apparatus according to the present invention includes a control code indicating a time-axis compression ratio of an audio signal time-axis-compressed to each sector of each track on a recording medium having a plurality of tracks in which a plurality of sectors can be set; A device for recording together with flags indicating the start, continuation and end of the audio signal, a time axis compression ratio indicating means for indicating a time axis compression ratio of the audio signal, and inputting the audio signal, A time axis compression unit for compressing the signal in accordance with the time axis compression ratio instructed by the time axis compression ratio instructing unit, and a time axis compressed audio signal output from the time axis compression unit; Generating means for generating the flag and the control code to be recorded on the recording medium; and instructing by the time axis compression ratio instructing means while recording the audio signal. When the time axis compression rate is changed, the flag indicating the continuation of the audio signal is set in the flag recorded together with the time axis compressed audio signal on the recording medium before the time point when the time axis compression rate is changed. Change to the flag indicating the end of the audio signal, and after the time axis compression rate is changed, time-base compress the audio signal according to the changed time-axis compression rate, and change the time axis together with the time-axis compressed audio signal. And a control unit for controlling the time axis compression unit and the generation unit so as to record a control code indicating an axis compression ratio on the recording medium.

[Action]

According to the above configuration, when the audio signal is compressed on the time axis and recorded continuously, the audio can be recorded with the time axis compression ratio changed in the middle without interruption.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a block diagram of the configuration, and FIG. 2 shows a flowchart of the operation. The same components as those in FIG. 3 are denoted by the same reference numerals.

Prior to recording on the disk 11, the time axis compression ratio of the audio signal is set in the CPU 10 manually or adaptively by a circuit (S1). When the recording start is instructed from the switch 12, the CPU 1
0 sends a control signal to the memory control circuit 14, and the memory control circuit 14 supplies a sampling clock and an address to the A / D converter 16 and the memory 18 at a cycle corresponding to the compression ratio, respectively. As a result, the input audio signal is frozen in the memory 18 (S2).

Here, when the CPU 10 is not instructed to change the compression ratio (S9), the subsequent operation is the same as that of the conventional example, and the track movement (S13), the setting of the flag and the control code (S5). , 6), Recording on Disk 11 (S7,8)
Is performed according to the presence or absence of the recording end signal from the switch 12.

On the other hand, when the compression rate is instructed to the CPU 10 and the sequence has already been recorded for one or more tracks, the CPU 10 outputs a track feed signal to the mechanism control circuit 20 to control the mechanism control. The circuit 20 moves the head 22 to the track on which the audio was recorded at the end of the sequence during continuous recording by a head feed mechanism (not shown) (S10). In this track, information that the sequence continues to the next track is recorded as a flag. Therefore, by rewriting this flag, the sequence can be ended at this track. Since the audio signal may be left as it is, only the flag portion may be rewritten by overwriting.

More specifically, the CPU 10 outputs a set signal to the memory control circuit 14 so that a flag indicating that the sequence ends at this track is recorded (S11). The memory control circuit 14 switches the switch 24 at a timing corresponding to the flag recording position in consideration of the length of the recorded audio signal in synchronization with the rotation of the disk 11, and supplies a new flag to the switch 24. The new flag is D / A converter 2
The signal is supplied to the FM modulator 28 via 6 and is FM-modulated. The switch 30 is closed for a period corresponding to the flag recording period in synchronization with the audio signal already recorded on the track. As a result, a flag indicating that the sequence ends at this track is recorded on this track (S12). Although moiré occurs in the flag portion due to overwriting, there is no problem since the voice recording portion is not overwritten.

Subsequently, the CPU 10 outputs a track feed signal to the mechanism control circuit 20, and moves the head 22 to a recordable track by a head feed mechanism (not shown) (S13). The operation after the movement of the track is the same as that of the conventional example described with reference to FIG. 4, and the sound is recorded on this track as a new sequence. Of course, on this track, audio data having a compression rate different from the previous one is recorded with a corresponding flag and control code added thereto. The compression ratio can be changed by changing the writing and / or reading speed of the memory 18.

When the CPU 10 is instructed to change the compression ratio and when recording is performed on the first track of the sequence, the subsequent operations are performed in the same manner as in the conventional example, such as track movement, flag and control / control. Code set, disk
Recording to 11 is performed. However, the audio data is recorded at the changed compression ratio. The change of the compression ratio is performed by writing to the memory 18 and / or
Alternatively, it can be realized by changing the reading speed.

As described above, the compression ratio can be changed even during continuous recording of audio.

In the control code of the track on which the flag is to be overwritten, the number of the next track is kept as it is, but the track number of the sector having a flag indicating the end of this sector is meaningless. There is no need to rewrite.

Criteria for changing the compression ratio include the storage capacity of the memory 18 or the amount of audio data stored in the memory 18 and the disk 11
The audio recording capacity per track may be automatically set. For example, assuming that a certain sequence is recorded at a compression ratio of 1/320, that is, about 5 seconds per track, the signal stored in the memory 18 is 5 seconds despite the fact that only one recordable track remains. Is exceeded, the signal stored in the memory 18 is automatically changed to a compression ratio that allows recording on the last track, and is recorded on the last track.

〔The invention's effect〕

As can be easily understood from the above description, according to the present invention, when the audio signal is compressed in the time axis and recorded continuously, the audio can be recorded by changing the time axis compression ratio in the middle without interruption. A recording device can be provided.
In particular, according to the present invention, when the number of recordable tracks on the recording medium is reduced, the audio signal can be recorded to the end without interruption by changing the time axis compression ratio to be increased during the recording operation. Become like

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, FIG. 2 is a flowchart showing the operation thereof, FIG. 3 is a block diagram showing the configuration of a conventional example, and FIG. 4 is a flowchart showing the operation of FIG. 10 ... CPU, 11 ... Disk, 12 ... Switch, 14 ...
Memory control circuit, 18 ... Memory, 20 ... Mechanism control circuit,
22 ... magnetic head, 28 ... FM modulator

Claims (1)

(57) [Claims] 1. A recording medium having a plurality of tracks in which a plurality of sectors can be set, a control code indicating a time axis compression ratio of a time axis compressed signal in each sector of each track and a control code of the audio signal. A device for recording together with flags indicating start, continuation and end, a time axis compression ratio indicating means for indicating a time axis compression ratio of an audio signal, an audio signal input, and a predetermined amount of the input audio signal. Every,
A time axis compression unit that performs time axis compression according to a time axis compression ratio instructed by the time axis compression ratio instruction unit; and a time axis compressed audio signal that is output from the time axis compression unit and is recorded on the recording medium. A flag and a generating means for generating the control code; and a time axis compression rate when the time axis compression rate specified by the time axis compression rate indicating means is changed during recording of the audio signal. In the flag that is recorded together with the time-axis-compressed audio signal on the recording medium before the time at which the time is changed, the flag indicating the continuation of the audio signal is changed to a flag indicating the end of the audio signal, and the time-axis compression ratio is changed. From the point of change, the audio signal is time-axis-compressed according to the changed time-axis compression rate, and a control indicating the changed time-axis compression rate together with the time-axis-compressed audio signal Sound recording apparatus, characterized in that it comprises a said time axis compression means to record the code on the recording medium and control means for controlling said generating means.