JPS5911316B2 - Still image recording and playback device with audio - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION 35. The present invention relates to a still image recording and reproducing device with audio that records still image information together with audio information for explaining the image on a rotating recording medium to obtain a still image with audio.

Upa Conventionally, still image recording and playback devices with audio have been equipped with magnetic disks,
A method was developed in which a still image information signal constituting a still image is recorded on one track of a rotating recording medium such as a magnetic sheet so that it can be played repeatedly, and an audio information signal for explaining the image is concentrically recorded on the other track. It's been done ~・ru.

Since this type of method requires an image explanation of 10 seconds or more for one still image information, the audio information signal is compressed on the time axis and recorded on a rotating recording medium, while the compressed audio information signal is expanded on the time axis. It is something to be regenerated. This compression/expansion of the time axis is performed by inputting a clock pulse with a frequency corresponding to the compression/expansion ratio into the auxiliary memory, writing the audio information signal, and then continuing. Both are generated by an oscillation circuit (
It was. Incidentally, in the rotation of the rotary recording medium, rotational unevenness of about 10H2 occurs due to the drive motor and the like. Therefore, when recording and reproducing the audio information signal, the above-mentioned rotational unevenness component is added to the audio information signal, so the reproduced audio may be affected by wow.
Distortion of first-class flutter occurs. Further, the auxiliary memory includes BBD, . Analog memory such as CCD is used.

Since it is difficult to obtain a large compression ratio with these memories,
Shift register and RAM that can sufficiently increase the compression ratio
It is desirable to use an IC memory such as the following as the auxiliary memory.
However, this type of memory requires converting the audio information signal into a digital signal, and in this case, the recording density on the rotating recording medium increases in proportion to the number of bits, which exceeds the recording density limit of the rotating recording medium. On the contrary, it becomes unreasonable to be unable to increase the compression ratio. The present invention cancels rotational unevenness of a rotating recording medium by forming a clock pulse input to the auxiliary memory from a color burst signal included in a reproduction signal of still image information, thereby reproducing audio information with less wow and flutter. Another object of the present invention is to provide a still image recording and reproducing device with audio that can use an IC memory as an auxiliary memory and can set a sufficiently large compression ratio.

The present invention will be specifically explained below based on the embodiment shown in the drawings.
The video information is 525H (H is the horizontal scanning period), which corresponds to one frame in the C method, and the rotating recording medium is 1 frame.
A magnetic disk that rotates at 800 rpm (525 H per revolution) is used, and the audio information signal has a frequency band f of 3K?
The explanation will be limited to an example set in .

In the block diagram of FIG. 1, a still image input from a television camera or the like is input through an input terminal 1, preprocessed by AGC, clip, clamp, etc. circuits 10, then FM-modulated by a modulation circuit 11, and then FM-modulated by a gate circuit 12. 1 frame (52
Still image information signals for 5H) are formed.

The gate circuit 12 is controlled to open and close by a 525H gate formed by separating a vertical synchronization signal from a still image input in a synchronization separation circuit 13 and dividing the frequency by i in a frequency division circuit 14. A still picture information signal for one frame is recorded and stored on one track 22 of the magnetic disk 2 via a recording amplifier 15 and a still picture information recording/reproducing head 20 as shown in FIG.

The motor 24 that drives the disk 2 is equipped with a servo circuit 25 that controls the phase to 1800 rpm using a reference signal obtained by dividing the vertical synchronization signal by one frequency.
For a 25H magnetic disk 2, one frame of still picture information signal is recorded exactly once on one track 22. On the other hand, the playback signal from the head 20 passes through a playback amplifier 16 and a limiter circuit 17, is FM demodulated by a demodulation circuit 18, and a still image information signal for one frame is repeatedly played back on a monitor television (not shown) connected to an output terminal 19. do.

The magnetic disk 2 has a diameter of 20 cm and can record approximately 50 pairs of still image information and audio information for explaining images, and the audio information signal for T seconds is transferred onto the recording track 22 of the still image information signal and the adjacent track 23. Compress the time axis and record concentric circles.

In the embodiment of FIG. 1, CCD, . An analog memory such as a BBD is used.Also, the first and second auxiliary memories 31 and 32 are used so that the storage capacity of the auxiliary memories 3 and 4 can be small.
. Configure it to be read in the auxiliary memory of (
・Ru. Furthermore, if the device is limited to recording and reproducing audio information signals separately, the auxiliary memory 3 on the recording side and the auxiliary memory 4 on the reproducing side can be used. In the illustrated example, an audio information signal for explaining an image obtained from a microphone or a tape recorder is inputted from an input terminal 50 to the auxiliary memory 3 for time axis compression.

The audio information signal is written into and read from the auxiliary memory 3 using clock pulses with frequencies Fl and f2.By the way, since the frequency band f of the audio information signal is 3KH2, the frequency F of the write clock pulse is 2f( 6KH2) or more, and if the compression ratio is 1, the frequency F2 of one read clock pulse can be set to m in Mfl (.

In this embodiment, the write clock pulse is formed by the pulse forming means 6 and the read clock pulse is generated by the oscillation circuit 7, but conversely, the read clock pulse is formed by the pulse forming means and the write clock pulse is generated by the oscillation circuit. Good too. The pulse forming means 6 is
Burst separation circuit 6 from FM demodulated still image information signal
1 extracts a color burst signal, operates the burst control oscillator 62 with this color burst signal to obtain a continuous wave with a frequency of 3.58 MH2, and further outputs a continuous wave with a frequency of 3.58 MH2.
3, the frequency is divided by 1 by the frequency divider circuit 64, and the frequency is 6.8KH2.
, while the oscillation circuit 7 generates a 3.58MH pulse signal.
Generate a pulse signal of z.

These pulse signals are used as the writing and reading clock pulses. However, if a wider frequency band of the audio information signal is required, 3.58MH2
The signal of PLO (PhascLOckedOscila
tOr) to a frequency having an integer ratio relationship with 3.58MH2. Therefore, in this example, what is the compression ratio? The 6.8 KHz pulse signal is input to the write clock gate 51 as a write clock pulse in the recording means 5, and the 3.58 MH2 pulse signal is input to the read clock gate circuit 52 as a read clock pulse.

These clock gate circuits 51 and 52 are alternately controlled to open and close with respect to the first and second auxiliary memories 31 and 32 using a 526H gate and a 1H gate, respectively. These gates are formed by a gate forming circuit 9, and a 1H gate forming circuit 9 separates a 15,750 Hz horizontal synchronizing signal from the FM demodulated still image information signal by a synchronizing separation circuit 91 and an AFC circuit 92.
3 to form a 1H gate, while the 526H gate is AF
The output of the C circuit 92 is divided by one frequency by the frequency dividing circuit 94 to 526H.
It is formed by the gate creation circuit 95.

The 526H gate alternately controls the opening and closing of the write clock gate circuit 51 for the first and second auxiliary memories 31 and 32 to alternately distribute write clock pulses, and the audio information signal shown in FIG. As shown in B and d, Al and A3 are written in the first auxiliary memory 31, and A2, A4, . . . are written in the second auxiliary memory 32 in units of 526H. On the other hand, the 1H gate alternately controls the opening and closing of the read clock gate circuit 52 for the first and second auxiliary memories 31 and 32, and alternately distributes read clock pulses from the first auxiliary memory 31 to the A
,,A3,... are transferred from the second auxiliary memory 32 to the compressed 1H audio information signals of A2, A4,...
The H audio information signals are read out alternately at a period of 526Hx2. In the above writing and reading, for example, when writing of A2 to the second auxiliary memory 32 is started, A, recorded in the first auxiliary memory 31 is compressed in time axis and read out. 1. The outputs of the second auxiliary memories 31 and 32 are mixed in the mixing circuit 53, FM-modulated in the modulation circuit 54, and the gate circuit 55 is opened and closed by the 1H gate shown in FIG. A compressed audio information signal is recorded and stored on the track 23 of the magnetic disk 2 via the signal recording/reproducing head 21. In this case,
While the magnetic disk 2 rotates at 525H per revolution, compressed 1H audio information signals are sequentially input to the disk 2 at a cycle of 526H. For example, as shown in FIG. 4, the first signal A, The recording start point Y1 of the next signal A2 is shifted by 1H from the recording start point X of the signal A2, and the signal A2 is recorded on the track 23 following the signal A1. Set the period of 1H gate to 526
This is why it is related to H. The audio information signal thus recorded on the magnetic disk 2 is reproduced by the reproducing means 8, and is FM demodulated by the demodulating circuit 85 through the reproducing amplifier 83 and limiter circuit 84 from the head 21, and is then subjected to FM demodulation by the demodulating circuit 85. The data is input to the auxiliary memory 4 for this purpose. The pulse signal of 3.58MH2 is sent to the reproducing means 8 (in this case, the 3.58 MH2 pulse signal is sent to the write clock gate circuit 81 as a write clock pulse).
is input to the first and second auxiliary memories 41 and 4 at the 1H gate.
On the other hand, the pulse signal of 6.8 KH2 is input to the read clock gate circuit 82 as a read clock pulse and is distributed to the first and second auxiliary memories 41 and 42 by the 526H gate. Therefore, the compressed audio information signal shown in FIG. 5a is written alternately into the first and second auxiliary memories 41 and 42 as shown in FIG.
, e, the time axis is expanded 526 times and read out alternately. In this case, for example, A1 is read out from the first auxiliary memory 41 (while A2 is read out to the second auxiliary memory 42).
is written. These first and second auxiliary memories 41, 42
A mixing circuit 86 mixes the outputs to obtain a continuous audio information signal as shown in FIG. As is clear from the above, since the time axis of the audio information signal of 526H is compressed to 1H and recorded on the magnetic disk 2 of 525H per rotation, the maximum time is T = (-x?) x 525 = 17.53 seconds. Audio information signals can be recorded and stored on one track 23.

Figure 2 shows the first and second IC memories 3 in the auxiliary memories 3 and 4.
Examples using 3, 34, 43, 44 are shown.
The recording means 5 converts the audio information signal into a digital signal using an A/D converter 57, and then writes and reads it into the first and second IC memories 33 and 34 using clock pulses from the pulse forming means 6 and the oscillation circuit 7. The outputs from the 5265 IC memories 33 and 34 are further mixed in a mixing circuit 53, converted back to analog signals in a D/A converter 58, and then FM modulated in a modulation circuit 54, and then sent to a gate circuit 55. The magnetic disk 2 is configured to record data from the head 21 through the recording amplifier 56 (open).

On the other hand, the compressed audio information signal is transmitted from the head 21 to the reproduction means 8, passes through a reproduction amplifier 83 and a limiter circuit 84, is FM demodulated by a modulation circuit 85, and is once converted into a digital signal by an A/D converter 88. 1st and 21st C memory 4
3 and 44, write and read data using clock pulses from the pulse forming means 6 and the oscillation circuit 7, expand the time axis by a factor of 526, mix in the mixing circuit 86, and then output the data to the D/A converter 87 again. The signal is converted into an analog signal and reproduced from the output terminal 89.

However, the magnetic disk 2 is rotated by a motor 24 or the like.
It contains a rotational unevenness component of about 0H2, and the rotational unevenness component is added as a frequency variation to the reproduced signal of still image information, and to the synchronously separated color burst signal.

Therefore, when the recording means 5 writes the audio information signal from the color burst signal into the auxiliary memory 3 using the write clock pulse formed by the pulse forming means 6, and reads it out using the read clock pulse from the oscillation circuit 7,
A rotational unevenness component is added to the compressed audio information signal read from the auxiliary memory 3.Thus, when recording this audio information signal, the rotation of the magnetic disk 2 includes the same rotational unevenness component. (For this reason, the audio information signal is recorded on the track 23 of the magnetic disk 2 with the uneven rotation component canceled.On the other hand, the audio information signal extracted from the magnetic disk 2 includes the rotation of the magnetic disk 2 during playback. Therefore, the audio information signal written into the auxiliary memory 4 by the write clock pulse from the oscillation circuit 7 contains a rotational unevenness component, but the pulse forming means 6 extracts the rotational unevenness component from the color burst signal. When reading with the read clock pulse that is formed, the rotational unevenness component included in the clock pulse cancels the rotational unevenness component included in the audio information signal, and the audio output reproduced at the output terminal 89 includes the rotational unevenness of the magnetic disk 2. Distortions such as wow and flutter caused by unevenness are removed.
As described above, the present invention forms one of the write clock pulse and the read clock pulse to be input to the auxiliary memories 3 and 4 from a color burst signal included in a reproduction signal of still image information, so that when recording an audio information signal and Since the uneven rotation of the magnetic disk 2 during reproduction is canceled, distortions such as wow and flutter caused by uneven rotation of the magnetic disk 2 can be eliminated.

In addition, IC memories are used for the auxiliary memories 3 and 4 (such that the audio information signal is A/D converted and inputted to the auxiliary memory 3, and the output of the auxiliary memory 3 is D/A converted and recorded on the rotating recording medium. and further performs A/D conversion from the rotating recording medium and stores it in the auxiliary memory 4.
Since the output of the auxiliary memory 4 is D/A converted and played back, a sufficiently large compression ratio can be achieved when compressing the time axis of the audio information signal and recording it on a rotating recording medium. It has excellent effects.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a still image recording and reproducing apparatus with audio according to the present invention, FIG. 2 is a block diagram of another embodiment in which IC memories are used as the auxiliary memories 3 and 4, and FIG. 3 is a block diagram of a magnetic disk Fig. 4 a to f are explanatory diagrams showing the principle of compressing the time axis of audio information signals; Fig. 5 a
to f are explanatory diagrams showing the principle of extending the time axis. 2... Magnetic disk, 3, 4... Auxiliary memory, 5.
...Recording means, 6. Pulse forming means, 7. Oscillation circuit, 8. Reproducing means.

Claims (1)

[Claims] 1. A still image information signal constituting a still image and a time-axis compressed audio information signal are recorded on a rotating recording medium, and an audio information signal is applied to the still image information that is repeatedly reproduced from the rotating recording medium. In a still image recording and reproducing device with audio that reproduces by expanding the time axis, a color burst signal containing a rotational unevenness component of a rotating recording medium is extracted from a reproduction signal of still image information, and a color burst signal is converted into an integer number according to the frequency band of the audio information signal. pulse forming means for forming a first clock pulse with a multiplied frequency f_1; and a second pulse forming means with a frequency f_2 related to the compression ratio (1/m) of the audio information signal with respect to the first clock pulse.
an oscillation circuit that generates a clock pulse;
a recording means for inputting a clock pulse into an auxiliary memory to compress the time axis of an audio information signal and recording it on a rotating recording medium; A still image recording and reproducing device with audio, comprising a reproducing means for expanding the time axis and reproducing. 2 The pulse generation circuit forms a first clock pulse with a frequency f_1 obtained by dividing the color burst signal by a compression ratio (1/m), and the oscillation circuit forms a first clock pulse with the same frequency (f_2, f_2=mf_1) as the color burst signal. 2. A still image recording and reproducing apparatus with audio according to claim 1, characterized in that the apparatus is configured to generate a second clock pulse. 3. A still image information signal constituting a still image and a time-axis compressed audio information signal are recorded on a rotating recording medium, and the audio information signal is expanded in time and reproduced for the still image information that is repeatedly reproduced from the rotating recording medium. In a still image recording and reproducing device with audio, a color burst signal containing a speed uneven component of a rotating recording medium is extracted from a reproduction signal of still image information, and the color burst signal is extracted at a frequency f_1, which is obtained by multiplying the color burst signal by an integer ratio according to the frequency band of the audio information signal. a pulse forming means for forming a clock pulse of 1; an oscillation circuit for generating a second clock pulse of a frequency f_2 related to a compression ratio (1/m) of the audio information signal with respect to the first clock pulse; , a recording means for inputting a second clock pulse into an IC memory to time-base compress the audio information signal after A/D conversion, converting the compressed audio information signal from D/A, and recording it on a rotating recording medium; Reproducing means inputs the first and second clock pulses into an IC memory, expands the time axis after A/D converting the audio output from the rotating recording medium, converts the expanded audio information signal from D/A, and reproduces the expanded audio information signal. A still image recording and reproducing device with audio, comprising: 4 The pulse generation circuit forms a first clock pulse with a frequency f_1 obtained by dividing the color burst signal by a compression ratio (1/m), and the oscillation circuit forms a first clock pulse with a frequency f_1 which is the same as the color burst signal (f_2, f_2=mf_1). 4. A still image recording and reproducing apparatus with audio according to claim 3, characterized in that the apparatus is configured to generate a second clock pulse.