JPH0256771A - Reproducing device - Google Patents

Abstract

PURPOSE:To prevent a mistake that trouble occurs in a device from being made by displaying an effect that a signal which is not correspondent is reproduced at such a time. CONSTITUTION:When a voice reproducing mode is set and a reproducing command switch is turned on, a system control part 64 refers to the track information of a RAM 68 so that a first voice track is accessed and a magnetic head 14 is positioned on the track. At the time of accessing the track, a voice reproducing signal is fetched in a memory 42 and the control part 64 discriminates the presence or absence of a corresponding video track based on the reproducing control information from an information signal demodulation circuit 60. When the corresponding track does not exist, an output from a monitor 38 is made in a mute state by a video mute circuit 36 and also Audio Only, etc., from a character generator 80 is displayed on a monitor 38. At the time of reproducing the voice having no corresponding video signal, the effect is displayed, so that there is no possibility of mistaking that the trouble occurs in the device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a reproducing device, and more specifically to a device for reproducing recorded signals from a storage means capable of recording video and audio.

[Conventional technology]

For example, there is a magnetic disk called a still video floppy that has a specified format for recording video and audio, and the standard states that either video or audio can be recorded on each track of the magnetic disk. is the track on which the audio signal is recorded (hereinafter referred to as
The track on which the video signal is recorded is called the audio track and the track on which the video signal is recorded is called the video track.In addition to the time-axis compressed audio signal, the track number of the track on which the related video signal is recorded and other control information are recorded. ing. In other words, there are two types of recording formats for recording audio signals on still video floppies: a single audio signal with no associated video recorded, and a recording format with associated video recorded. Note that three types of time axis compression ratios are available, and the audio playback time per track is 5 seconds, 10 seconds, and 30 seconds.

When playing an audio signal recorded on a still video floppy, a specified audio track is played, and based on the control information signal recorded there, it is determined whether there is a recording trunk for the related video signal. Import the reproduced audio signal into the audio memory. Then, the video track obtained by the control information signal is accessed and the video is played back, and then the stored signal in the audio memory is played back while being time-expanded.

[Problem to be solved by the invention]

In the conventional example above, if there is a related video track, the video will appear on the screen of the video monitoring device, so there is no problem, but if there is no related video track, the monitor screen output is muted and the audio Only the signal was being played. Therefore, if the audio signal is recorded alone, nothing will be displayed on the monitor screen, and there is a high possibility that the operator will conclude that the device is malfunctioning. Also,
It is not possible to distinguish between a case where the related video signal is actually recorded and a case where it is not displayed on the monitor screen due to some kind of failure.

Such problems occur with both audio and video signals. In other words, with the conventional device, it has not been possible to reliably determine whether or not there is a track in which a signal related to the signal recorded on a given track exists, and to notify the user.

Therefore, it is an object of the present invention to provide a playback device that is easy to operate and avoids such misunderstandings.

[Means to solve the problem]

A playback device according to the present invention is a device that plays back video and audio from a recordable storage device, and includes a determining device for determining whether or not a signal corresponding to a signal recorded in a predetermined block is recorded; The present invention is characterized by comprising a display means for performing a predetermined display when a corresponding signal does not exist according to the determination result of the means.

[Effect]

By means of the above means, when a signal for which there is no corresponding signal is reproduced, a predetermined display to that effect is displayed, thereby eliminating the possibility of misidentification as a failure of the apparatus.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a block diagram of an embodiment of the present invention. 1
0 is a magnetic disk, 12 is a DC motor for rotating the magnetic disk 10, 14 is a magnetic head, 16 is a head moving mechanism that moves the magnetic head 14 in the radial direction of the magnetic disk 10, and 18 is a drive unit for driving the head moving mechanism 16. 20 is a motor drive circuit that drives the motor 18;
2 is an innermost track detection switch that is closed when the magnetic head 14 accesses the innermost track of the magnetic disk 10; 24 is a PG pulse generation circuit that generates 1 pulse per rotation of the magnetic disk 10; 26 is a PG pulse generation circuit; DC motor 1
A motor drive circuit 28 is a servo circuit that controls the motor drive circuit 26 so that the magnetic disk 10 rotates at a constant speed in accordance with PG pulses from the PG pulse generation circuit 24.

30 is a reproduction amplifier, 32 is an FM demodulation circuit, 34 is a video signal processing circuit, 36 is a video mute circuit, and 38 is a video monitor device. 40 is an A/D converter that digitizes the output of the FMI adjustment circuit 32; 42 is a memory; 44 is a D/A converter that digitizes the output of the memory 42; 46 is a write and read line for the memory 42; This is a memory control circuit that controls the address. The A/converter 40 performs A/D conversion according to the output pulse of the oscillator 48, the memory control circuit 46 controls writing to the memory 42, and the oscillator 50
According to the output pulse of the memory control circuit 46, the memory 42
The D/A converter 44 performs D/A conversion. A/D converter 40, memory 42 and D/A converter 44
constitutes a time axis expansion circuit. 52 is a D/A converter 44
54 is an audio mute circuit, and 56 is a speaker.

58 is a timing generation circuit that generates a timing signal according to the output pulse of the PG pulse generation circuit 24; 60 is an information signal demodulation circuit that demodulates a control information signal from the output of the FM demodulation circuit 32 under the timing signal from the timing generation circuit 58; It is.

A portion of the information demodulated by the information signal demodulation circuit 60 is also supplied to the timing generation circuit 58.

Reference numeral 62 is a discrimination circuit that discriminates whether the reproduced signal is a video signal or something else. 64 is a system control circuit that centrally controls the entire system, and also has a function of determining the presence or absence of a video signal corresponding to an audio signal from the demodulated data of the information signal demodulation circuit 60. 66 is a ROM that stores an operating program for the system control circuit; 68 is a system control circuit 64;
RAM for storing various variables during operation, 70
72 is an amplifier switch that instructs the movement of the magnetic head 14 to the inner track, 72 is a down switch that instructs movement to the outer trough 7, and 74 is an on/off switch for the audio playback mode.
It's an off switch.

76 is a detection circuit consisting of a phototransistor and a light emitting diode and detects the presence or absence of a magnetic disk; 78 is an envelope detection circuit that discriminates from the output of the reproduction amplifier 30 whether it is an empty track or a recorded track; the circuit 76.
The detection result of 78 is applied to the system control circuit 64.

80 is a character generator (CG) that generates a display to that effect, for example, "Audio 0nly" when an audio signal with no corresponding video is being played; 82 is a CG
This is an adder that adds the pattern signal generated by 30 to the output of the video mute circuit 36. .

Next, the operation shown in FIG. 1 will be explained. First, magnetic disk 10
The number of tracks formed is 50, and the outermost track is the first track, and the innermost track is the 50th rack. Further, the operation of moving the magnetic head 14 toward the inner circumference will be referred to as trunk up, and the operation of moving the magnetic head 14 toward the outer circumference will be referred to as track down.

FIG. 2 shows a flowchart of the operation when the magnetic disk 10 is set. When power is supplied to the illustrated device by operating a power switch (not shown), the system control circuit 64 is reset and initialized. At this time, both the mute circuits 36 and 54 are initialized so that their outputs are muted. After initial setting, loading of the magnetic disk 10 is waited (Sl). Whether or not the magnetic disk 10 has been loaded can be determined from the output of the disk detection circuit 76. When the magnetic disk 10 is loaded, the system control circuit 64 controls the servo circuit 28 to rotate the magnetic disk 10 by the motor drive circuit 26 and the DC motor 12 (S2). The innermost track detection switch 22 checks whether the magnetic head 14 is accessing the innermost 50th track. If the switch 22 is not closed, the track moving mechanism 16 moves the magnetic head 14. Track up by one track (S4).

S3. By S4, the magnetic head 14 is positioned on the 50th track.

When the magnetic head 14 is positioned on the innermost track,
50 is assigned to the variable N of RAM6B (S5).

N is a variable that indicates the number of the track currently being accessed by the magnetic disk 14, and the attribute information of each track on the loaded magnetic disk 14 (i.e., whether it is unrecorded or recorded, whether it is an audio track or a video track, For audio tracks,
Develop an array or table T (N) in which the corresponding video track numbers, etc.) are arranged.

In order to confirm whether the magnetic disk 14 is loaded normally, check whether the DC motor 12 is operating (
S6), if it is not operating, return to sl. Next, it is checked whether the track is empty or not based on the output of the envelope detection circuit 78 (S7), and if it is not an empty track, it is determined whether the reproduced signal is a video signal or not based on the output of the discrimination circuit 62 (S8), and the video signal is If not, load the playback control information into the RAM 68 (SIO). If it is a video track, set the code "11" to the table T (N) (S9), if it is an empty track, set the code to T (N). ”
00" (512), and if it is not an empty track and is not a video trunk, set code "10" to T (N).
” (Sll).

Check whether N is 1 or not (S13), and if it is 1, end,
If not, move down one track by 5
14) Decrement N (S15) and return to S7. In other words, steps 87 to S15 are looped for all tracks, and information on whether each track is an empty track, a video track, or an audio trunk is stored in the table T (N
) The operation of actually reproducing audio signals from the magnetic disk 14 will be described with reference to FIG. First, the audio reproduction mode is set (520), and a reproduction command switch (not shown) is turned on. In response, the variable N is set to 1, and while N is incremented sequentially, the table T (N) in the RAM 68 is set.
Check the codes in order (S22゜23), and first select the code "
The magnetic head 14 is positioned at the track number 10'' (code indicating that it is an audio track) (S24).

Determine the playback control information signal for that track5.
25) Check whether it is the first audio trunk of the audio sequence based on the playback control information signal (526);
If it is not the first audio trunk, the magnetic head 14 is sent to the first audio track (S27). S25~27°
This will cue the audio sequence.

At the time when the first track of the audio sequence is accessed, the played audio signal is captured into the memory 42 (528);
The presence or absence of a corresponding video track is determined from the reproduction control information signal (S29). If there is no corresponding video track, the video mute circuit 36 mutes the monitor output (S30), and the CO2
0 to "Audio 0nly" is output and displayed on the video monitor device 38 (S31). Simultaneously with this monitor display, the signal stored in the memory 42 is read out and audio reproduction is started (S32).

Also, if there is a corresponding video track in S29,
Send the magnetic head 14 to the video track (S33)
Then, the number of the reproduced audio sequence is displayed on the screen of the video monitor device 38 (S34), and the reproduction of the audio signal and video signal is started (535).

When capturing the reproduced audio signal into the memory 42, the A/D
The converter 40 performs A/D conversion according to the output pulse of the oscillator 48, and the memory control circuit 46 controls the write address of the memory 42 according to the timing pulse output from the timing generation circuit 58 and the oscillator 48. do. The system control circuit 64 controls the memory control circuit 46 to control the reading speed from the memory 42 according to the time axis compression rate included in the reproduction control information signal. This results in
In the recording state, the audio signal, which was compressed on the time axis, is expanded on the time axis and returned to its original band.

According to the audio reproduction process shown in FIG. 3, when audio reproduction is instructed, even if continuous audio is recorded across multiple tracks, the magnetic head 14 accesses a track in the middle of the audio. You can automatically play back and listen to the audio from the beginning of the continuous audio even if the audio is played.

In the above embodiments, a disc-shaped recording medium was used as an example, but the present invention is not limited to the type or accounting of the recording medium, and as long as it is capable of recording a mixture of audio and video signals, For example, it may be in the form of a tape or a solid state memory such as a semiconductor memory. In addition, when there is no video corresponding to an audio sequence, the screen display may be various characters, specific symbols or images, and when there is a video corresponding to the audio sequence, the display may be the number of the played audio sequence. In addition, the number of the reproduced video track may also be included. In this embodiment, the presence or absence of a compatible video signal is determined by the system control circuit 64, but a dedicated circuit for this determination may also be provided. Needless to say, it's a good thing.

〔Effect of the invention〕

As can be easily understood from the above explanation, according to the present invention, even when playing back a signal for which no corresponding signal has been recorded, a display to that effect is displayed, so that the operator can instantly record, for example, an audio recording. This eliminates the risk of making incorrect decisions such as equipment failure.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the configuration of an embodiment of the present invention, and FIGS. 2 and 3 are flowcharts of the operation of FIG. 1. 10-m-magnetic disk 14...magnetic head 16
Head movement mechanism 22-Innermost track detection switch
24-PG pulse generation circuit 56-Speaker 70...-
Up switch 72-Down switch 74-Audio playback mode on/off switch 2-Notara diagram

Claims (2)

[Claims] (1) A device that reproduces video and audio from a recordable storage device, which includes a determining device that determines whether or not a signal corresponding to a signal recorded in a predetermined block is recorded, and according to the determination result of the determining device. 1. A playback device comprising: display means for displaying a predetermined display when a corresponding signal is not present. (2) The reproducing apparatus according to claim 1, wherein the determining means is means for determining whether or not a video signal corresponding to an audio signal recorded in a predetermined block is recorded.