JPH0675281B2 - Video signal recorder - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video signal recording device, and more particularly to a video signal recording device having means for recording one field of an analog video signal on one track.

[Conventional technology]

This kind of conventional recording / reproducing apparatus does not have a combined use device capable of separately recording a moving image and a still image. Forcibly, a magnetic recording / reproducing device for moving images (VT
R) is used to easily reproduce a still image as one frame in a moving image in a so-called reproduction pause mode or the like, and the image quality of this still image is almost inferior to that of the moving image.

Here, regarding the conventional so-called 8 mm VTR still image playback,
It will be described with reference to the drawings.

In FIG. 7, 101 is a magnetic tape (hereinafter referred to as tape), 102 is a pinch roller, 103 is a capstan motor,
104 is a rotating drum, 105 is a pulse (PG) generator related to the rotation phase of the drum 104, 106 is a frequency signal (drum FG) generator related to the rotation speed of the drum 104, 107, 108, 112, 114, 11
5, 119 are amplifiers, 109 is a drum phase control circuit, 110 is a drum speed control circuit, 111 and 118 are adders, 116 is a tracking error (ATF) signal generator, and 113 is a frequency related to the rotation speed of the capstan motor 103. Signal (Capstan F
G) generator, 117 is a capstan speed control circuit, 120,12
1 is a magnetic head (hereinafter referred to as a head).

In FIG. 7, the rotary drum 104 is a drum PG and a drum F.
Based on G, the phase error signal from the phase control circuit 109 and the speed error signal from the speed control circuit 110 are added by the adder 11 and driven by the added signal. Thereby, the rotation of the drum 104 is controlled so as to correct these errors.

On the other hand, the capstan motor 103 adds to the speed error signal from the speed control circuit 117 obtained based on the capstan FG,
Tracking control is performed using an ATF (Automatic Tracking Finding) signal from an ATF signal generator 116 based on the four-frequency pilot method.

Therefore, in the still image playback state, () or (
), The head is traced on the magnetic tape by the circuit shown in FIG.

FIG. 8 shows () so-called frame still reproduction and (
FIG. 6 is a diagram showing a traced state of heads on a tape during so-called field still reproduction. Hereinafter, FIG. 8 will be described.

In FIG. 8, () frame still reproduction is one in which two fields are alternately reproduced, and two heads A and B are alternately used to reproduce only the heads A and B and the tracks in which the azimuths match. Therefore, the reproduction area per line is about 1/2 of that in the case of normal reproduction, and the S / N is deteriorated. Moreover,
Since the video signals of these two fields have a time difference of 1/60 second, there is a possibility that the still image may be blurred in a fast-moving scene.

() In field still reproduction, only one field of the video signal that composes one frame from two fields is dedicated to a still image dedicated head (two heads of the same azimuth with different 180 ° phases). Play repeatedly. Therefore, although blurring such as frame still reproduction does not occur, in principle, deterioration of S / N and deterioration of vertical resolution are inevitable compared with normal reproduction.

[Problems to be solved by the invention]

Generally speaking, from the viewpoint of human visual characteristics, a high image quality is required for a still image rather than a moving image. Further, in the case of a still image, it may be considered that the image is printed out and fixed on a paper sheet for viewing, so that higher image quality is required. However, the conventional VTR still image has a drawback that the image quality is deteriorated due to the above-mentioned reason, as compared with the moving image.

The present invention has been made in view of such drawbacks, and provides a video signal recording apparatus capable of recording a moving image and a desired screen in the moving image as a high-definition still image in the same device. The purpose is to

[Means for solving problems]

For the above-mentioned purpose, the video signal recording apparatus according to the present invention comprises a recording means for recording signals while sequentially forming tracks having first and second recording areas on a recording medium, and an analog moving image signal. Input means for inputting, and an analog signal processing means for processing the analog moving image signal and supplying each field to the recording means at a transmission rate at which each field is recorded in the first area of each track; A storage unit for taking in one frame of the analog moving image signal from the storage unit and storing it as a still image signal, and a still image signal surrounded by the storage unit for storing one field in a plurality of tracks in the second area. And a digital signal processing means for supplying to the storage means at a predetermined transmission rate.

[Action]

With the above-described structure, a high-definition still image can be recorded by digitalizing a video signal of a field desired to be recorded as a still image and recording it on a plurality of tracks.

〔Example〕

Hereinafter, the basic idea when the present invention is applied to a VTR will be described.

Generally, the optical system of a commercially available video camera has a band margin for recording a moving image by a VTR. Therefore, the same optical system is used to supply a signal to a still image system signal processing circuit in addition to a moving image system signal processing circuit. In this still image system signal processing circuit, the supplied signal is time-axis converted, digitally processed and recorded. As a result, a wideband still image signal can be recorded in the recordable band. Further, as the digital recording format at this time, the signal processing circuit can be partially shared by recording in accordance with the recording format of the PCM audio of 8 mm VTR. However, as will be described later, identification (ID) signal data indicating a still image signal is recorded.

Since the amount of still image data in the same period is significantly different from the amount of audio data, the analog digitally converted video signal is temporarily stored in the frame memory at the timing corresponding to the shutter release in the camera. Stored in. Then, the digital video data is read from the frame memory at the transmission rate according to the recordable band and recorded on the tape.

FIG. 1 is a block diagram showing a schematic configuration of an apparatus according to an embodiment of the present invention. 500 is an analog video signal processing circuit for moving images, 501 is an electrode conversion system, 502 is a magnetic tape,
Reference numeral 503 is a PCM signal processing circuit, 504 is an optical system, 505 is an image sensor as an input means of a moving image signal, 506 is a still image digital video signal processing circuit, 507 is a control circuit, and 508 is a switch.

The apparatus shown in FIG. 1 has a still image signal processing circuit 507 and a still image signal control circuit 50 in addition to the conventional camera-integrated 8 mm VTR circuit configuration.
7. Three circuits, a moving image / still image switching circuit 508, are added.

FIG. 2 shows details of the still image signal processing circuit 506 and the PCM signal processing circuit 503 of FIG. 1, in which 601 is an analog / digital converter (hereinafter referred to as an A / D converter) and 602. Is a frame memory composed of RAM, 603 is a system controller, 604 is an address generator, and 605 is a switch.

First, an image is formed on the sensor 505 by the optical system, and its output is supplied to the A / D converter 601. A / D converter 6
All the information digitized in 01 is temporarily stored in the frame memory 602. The writing control to the frame memory 602 is controlled by the system controller 603 and the address generator 604.
Will be held in.

Now, the shutter release instruction is the system controller
Upon entering 603, an address reset / instruction is sent to the address generator 604, and writing of a video signal for one frame as a still image signal is started from the head address of the frame memory 602. Return to system controller 603. In response to this end pulse, the controller 603 gives a low speed read instruction next. Here, the low speed means that the transmission rate is low, and the time axis is expanded on the time axis.

Next, the read signal is supplied to the redundant data addition circuit 605 in the PCM signal processing circuit 503 through the switch 605 for still video / audio switching, and the redundant code such as ID and error correction code (ECC) is added. The post-modulation circuit 606 modulates the signal and supplies it to the S-side terminal of the next switching switch (508) (FIG. 1).

The output signal processing of the switch 508 is recorded on the tape 502 by the electromagnetic conversion system 501 without any change from the conventional VTR.

Here, the data amount of the still image video signal will be described below.

FIG. 5 shows the recording format of the PCM audio signal in the 8 mm VTR.

In FIG. 5, Sync is synchronization data, A0 to A131 are address data, ID0 to ID5 are additional data, and R0 to R524.
Each is the right (R) channel audio data, L0 to L5
24 is the left (L) channel audio data, Q0-
Q131 and P0 to P131 are error correction redundant data, and CRC is a known cyclic code for error detection. R0 ~ R524, L0 ~ L52
Each 4 is a data word of 8 bits. These are recorded per field period of the video signal. In FIG. 6, 401 is an area in which an analog video signal for one field is recorded per track, and 402 is an area per track.
This is an area where the PCM audio signal compressed in the time axis during the field period is recorded by the above format.

Therefore, 1050 including L and R channels of stereo signal
Field information can be recorded every time. Since 1 word = 8 bits, if the video signal is quantized with 8 bits, it corresponds to the data amount of one pixel.
Now, assuming that the number of pixels to be digitalized is about (500 x 500), in the component system that digitizes R, G, and B colors independently, one frame is (500 x 500 x 3) words,
Since the number of words in the audio area per second is 1050 × 60 words, the recording time of ((500 × 500 × 3) / (1050 × 60) ≈12) seconds is 1 to record a still image by this format. Required per frame.

Further, even in the composite system in which the luminance signal and the chrominance signal are not separated and are digitalized, for example, when the sampling frequency is 3 fsc, about 6 seconds are required. (Fsc is the color subcarrier frequency) Therefore, such a recording is divided into 6 tracks and
Using a format that records channel audio signals, the amount of information that can be recorded per field is 6
Doubled, recording time is reduced to 1/6. Therefore, in this case, the component method is 2 seconds, the sampling frequency
It takes about 1 second with the 3fsc composite method. 403 in FIG.
Shows the recording pattern at this time.

FIG. 3 is a block diagram of a recording apparatus according to another embodiment of the present invention, which has a circuit configuration in which a photographing device and a frame memory for video signals are shared in order to miniaturize the photographing device.

In FIG. 3, 801 is an optical system, 803 is a read control circuit, and 804
Is a system controller, 805, 807 and 812 are switches respectively, 806 is an analog video signal processing circuit, 808 is an electromagnetic conversion system, 809 is a tape, 810 is an audio encoder, 811 is A.
A / D converter, 813 is a parallel-serial converter, 814 is a redundant data adding circuit, 815 is a digital modulator, and 802 is an image sensor described in detail below.

Now, the subject is imaged on the image sensor 802 via the optical system 801. The image sensor 802 is a non-destructive read element, and even if a video signal is read once, the content of this type of element is stored without being destroyed, so that the element itself has a memory function. By utilizing this memory function, the digital frame memory in the device shown in FIG. 1 can be omitted.

The reading of the image sensor 802 which also serves as the memory is performed by a dedicated read control circuit 803. The read control circuit 803 is controlled by the system controller 804. Also, the system controller 804 is a switch for information switching 805, 807, 8
There are also 12 switches.

Now, when the user is trying to record a moving image and is performing an operation associated therewith, the shutter 800 is always open and the video signal corresponding to the moving image is sequentially read from the image sensor 802.

At this time, the switch 805 is connected to the side a, and the information read from the image sensor 802 is processed as an analog video signal by the analog video signal processing circuit 806, passes through the switch 807, and is transferred onto the tape 809 by the electromagnetic conversion system 808. Is recorded to.

When the user tries to record a still image and performs an operation associated with this, the shutter 800 is closed, and if the switch 805 is connected to the side b, the information read from the image sensor 802 is digital still. It is processed as an image signal. That is, the A / D converter 811 converts the digital data into 8-bit digital data. This data is audio encoder 810
It has the same appearance as the PCM audio signal processed by the above. These two types of signals are the system controller
By switching the switch 812 in accordance with the recording mode designated by 804, the 8-bit parallel signal thus obtained is selectively output, and the parallel-serial converter 813 converts the parallel signal into a serial signal. Next, this signal provides identification information on whether the audio data is still image data or the additional data (ID
0 to ID8) and the error correction code is added at the same time by the redundancy addition circuit 814. After that, this signal is digitally modulated by a digital modulator 815, electromagnetically converted by a electromagnetic conversion system 808 via a switch 807, and a tape
Recorded in 809.

Further, FIG. 4 is a block diagram of a reproducing circuit corresponding to the recording apparatus as described above. In FIG. 4, 700 is a tape, 701 is an electromagnetic conversion system, 702, 704 and 714 are switches, and 703.
Is an analog video signal processing circuit, 705 is a digital demodulation circuit, 706 is an error correction circuit, 707 is a serial-parallel conversion circuit,
708 is an ID detection circuit, 709 is a system controller, 710 is an audio decoder, 711 is a frame memory, 712 is an address generator, and 713 is a digital / analog converter (D / A converter).

Now, the information recorded on the tape 700 is reproduced as an electric signal by an electromagnetic conversion system 701 including a head, a rotary transformer and the like. This signal is a switch 70 for switching.
2, the analog video signal processing circuit 703 or the digital demodulation circuit 705 is supplied to one of the still image processing circuits. If the switch 702 is connected to the a side, the signal is analog-signal processed as a moving image and is output as a normal analog video signal via the switch 704.

On the other hand, if the switch 702 is connected to the b side, the signal is demodulated as a digital signal by the digital demodulation circuit 705, error-corrected by the error correction circuit 706, and serial-parallel conversion circuit 707 converts the serial data into parallel 8-bit data. To be converted. The switch 714 is switched according to the content of the information, and the audio decoder 710 or the video frame memory 7
Divided into 11 This switching of the switch 714 is performed by the ID detection section 708 which includes identification information regarding the audio data or the still image data included in the reproduction signal together with other additional data.
Detected by and is controlled by the system controller 709. In addition to this, the system controller 709 switches the switches 702 and 704 based on the operation of an operation unit (not shown).
Further, the controller 709 includes an address data generator 712.
Determines the address data to be generated. Writing and reading with respect to the frame memory 711 are controlled according to the address of the address generator 712.

In this way, the data string read in the sequence that reproduces the form of the video signal is supplied to the switch 704 for switching as an analog signal by the D / A converter 713. The switch 704 outputs a video signal of a still image or a moving image.

〔The invention's effect〕

As described above, the present invention can provide a video signal recording device capable of recording a moving image and a desired screen in the moving image as a still image with higher definition than the moving image in the same device.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a recording apparatus as an embodiment of the present invention, FIG. 2 is a block diagram showing details of a still image signal processing circuit and a PCM signal processing circuit of FIG. 1, and FIG. Is a block diagram of a reproducing circuit corresponding to the apparatus shown in FIGS. 1 and 3, FIG. 3 is a block diagram of a recording apparatus as another embodiment of the present invention, and FIG. 5 is an RCM audio system in an 8 mm VTR. FIG. 6 shows a signal recording format, FIG. 6 shows a recording pattern on a magnetic tape, and FIG. 7 shows a conventional recording pattern.
FIG. 8 is a diagram showing a main configuration for tracking control in a VTR, and FIG. 8 is a diagram showing a positional relationship between the tape and the head during still reproduction. In the figure, 500 is an analog video signal processing circuit for moving images, 501 is an electromagnetic conversion system, 502 is a magnetic tape, 503 is a PCM signal processing circuit, 504 is an optical system, 505 is an image sensor, 506 is a still image signal processing circuit, 507 is a control circuit and 508 is a switch.

Claims (1)

[Claims] 1. A recording means for recording a signal while sequentially forming tracks having first and second recording areas on a recording medium, an input means for inputting an analog moving image signal, and the analog moving image signal. An analog signal processing means for processing each field, and supplying each field to the recording means at a transmission rate recorded in the first area of each track, and one frame of the analog moving image signal from the input means. Storage means for capturing and storing as a still image signal, and a digital means for supplying the still image signal captured in the storage means to the recording means at a transmission rate at which one field is recorded in the second area of a plurality of tracks. A video signal recording device comprising signal processing means.