KR920000817Y1 - Picture image play back circuit of still video camera - Google Patents

Abstract

No content.

Description

Video playback circuit of still video camera

1 is a conventional circuit diagram.

2 is a circuit diagram of the present invention.

* Explanation of symbols for the main parts of the drawings

1 imaging device 2 signal processor

3: modulation section 4: recording / playback section

5: magnetic disk 6: automatic gain control unit

7: demodulator 8: timing generator

9: synchronization signal generator 10: eraser

11: Encoder 12: Mode Control

13: playback control microcomputer 14: mechanism control microcomputer

15: motor drive unit 16: pulse generator

21: digital / analog converter 22: field memory

23: analog / digital converter 24: memory controller

25: pulse generator 26: separation / coupling unit

The present invention relates to a video signal reproducing circuit in a still video camera. In particular, the video signal read out from a magnetic disk (FDD) is stored in a separate video memory for playback, and the video information of the magnetic disk is transferred to the video memory. The present invention relates to a video reproducing circuit of a still video camera, which separates the head from the disk to prevent damage to the head and the magnetic disk.

In general, the playback circuit of a still video camera (Still Video Ca mera: SVC) for recording and playing back still images is configured as shown in FIG. 1 and operated as follows.

The imaging device 1 converts a signal of light into an electrical signal and transmits the signal to the signal processor 2. The signal processor 2 separates the R, G, and B (Red, Green, Blue) color signals output from the imaging device 1 into color difference signals and luminance signals under the control of the synchronization signal generator 9. The separated color difference signal and the luminance signal are frequency-modulated by the modulator 3 and transmitted to the recording / reproducing head amplifier 4, respectively.

Here, the role of the recording / reproducing head amplifier is to amplify the video signal read by the head from the magnetic disk and store it to the AGC (Automatic Gain Control) 6. Role.

The AGC 6 processes the RF signal by the RF signal, and transmits the image signal read from the head to the demodulator 7 during reproduction. The demodulator 7 outputs the luminance and color difference signals, which are frequency-modulated by the modulator 3, respectively. Demodulate

The demodulated signal is input to the encoder 11, and the encoder 11 converts the color difference signal and the luminance signal separated by the signal processor 2 into R, G, and B signals, and outputs the converted R, G, and B signals. The mode control vicom 12 is controlled by the mode selection switch SW1 of the SVC and the stroboscopic sensor (not shown). To control. When the switch SW2 such as play, erase, track setting, etc. is selected by controlling the timing generator 8, the play control microcomputer 13 is connected to the mode control microcomputer 12 and the mechanism control microcomputer 14 via a bus. Control the system so that the selected function can be performed.

The mechanism control microcomputer 14 is controlled by the mode control microcomputer 12 and the regeneration control microcomputer 13, and controls the FDD unit 5 in the motor drive mode.

In the conventional still video camera video playback signal operating as described above, the head has to continuously read the video signal of the magnetic disk when the video signal recorded on the magnetic disk is reproduced, thereby causing damage to the head and the magnetic disk. . In addition, due to the continuous movement of the head, rotation of the disk and external impact, the head or disk drive shakes, which causes distortion of the playback screen.

Therefore, the object of the present invention is to store the signal read from the magnetic disk several times by the head in the image memory and then to separate the head and the disk to prevent damage to the head and the disk and to store the image signal stored in the image memory. The present invention provides an image playback signal of a still video camera that can reproduce a screen with low distortion by outputting the same.

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

FIG. 2 is a system block diagram of the present invention, wherein the analog / digital converter 23 and the field memory 22 and the digital analog are provided between the demodulator 7 and the encoder 11 of the circuit having the same configuration as those of FIG. The converter 21, the memory control section 24, and the pulse generating section 25 are added and connected, and the separating / coupling section 26 is added between the mechanism control microcomputer 14 and the motor driving section 15.

The analog-to-digital converter 23 digitizes the output of the demodulator 7 and the field memory 22 stores the digital signal. The digital-to-analog converter 21 analogizes the digital signal output from the field memory 22 and outputs the analog signal to the encoder 11. The memory controller 24 receives a predetermined pulse from the pulse generator 25 to control the digital / analog converter 21, the field memory 22, and the analog / digital converter 23. .

In addition, the separating / combining unit 26 performs an operation of separating the head from the magnetic disk by the mechanism control microcom 14 under the control of the memory control unit 24.

Based on the above-described configuration will be described the present invention in detail.

The signal demodulated by the demodulator 7 through the above-described operation of FIG. 1 is converted into a digital signal through the analog-to-digital converter 23. At this time, the field memory 22 records the digital production signal under the control of the memory controller 24 for the entire field memory system.

At this time, the field memory can store only one field of the video signal of the magnetic disk.

The signal output from the field memory 22 is converted into an analog signal through the digital / analog converter 21 and input to the encoder 11. The encoder 11 combines the color difference signal and the luminance signal separated by the signal processing unit 2 into R, G, and B signals.

At this time, if one field signal read from the magnetic disk is stored in the field memory, the memory control unit 24 performs the operation of separating the head from the magnetic disk by the mechanism control microcomputer 14 controlling the separation / combining unit 26. To control.

As described above, the video signal read from the magnetic disk is stored in a separate memory for playback, and the video information is transferred to the video memory so that the head is separated from the disk, thereby eliminating the need for continuous playback of the FDD. It has the advantage of preventing the wear of the magnetic disk and the head during prolonged playback and minimizing the on-screen distortion caused by the tremor and external impact caused by mechanical instability of the magnetic disk driver.

Claims (1)

Image pickup device 1, signal processing section 2, modulation section 3, recording / reproducing section 4, automatic gain controller 6, magnetic disk 5, erasing section 10, motor driving section 15 In the video signal reproducing circuit of a still video camera having a mode control microcomputer 12, a playback control microcomputer 13, a mechanism control microcomputer 14, a demodulator 7, and an encoder 11, the demodulator ( 7) an analog digital converter 23 for digitally converting the video signal outputted from the video signal, a field memory 22 for storing the digital demodulated signal under predetermined control, and an output data of the field memory 22. Control the operation of the digital / analog converter 21, the analog / digital converter 23, the field memory 22, and the digital / analog converter 21 outputted to the encoder 11 And a head separation signal S1 to the mechanism control microcomputer 14 when one field signal is recorded in the field memory 22. Head from the magnetic disk (5) under the control of the memory control unit (24) for generating the control unit, the pulse generating unit (25) for generating a predetermined pulse to control the memory control unit, and the mechanism control microcomputer (14). A circuit, characterized in that consisting of a separation / coupling part 26 to space the.