JPS60194683A - Method and device for recording video signal - Google Patents

Abstract

PURPOSE:To improve the use efficiency of recording tracks by recording a discrimination signal which indicates a video signal of a half-tone image or binary image together with said video signal, and performing reproduction processing during reproduction according to said discrimination signal. CONSTITUTION:A changeover switch 15 is connected to a terminal 15b in the 1st mode wherein a half-tone image is photographed and recorded and to a terminal 15a in the 2nd mode wherein a binary image is photographed and recorded. A discrimination signal generator 16 generates a discrimination signal indicating one of the two modes simultaneously with the operation of the switch 15 and supplies the signal to a recording head moving mechanism. When one field is recorded after the last field is recorded in the 1st mode, a multihead 7 is moved by six recording tracks, and in the 2nd mode, the head is moved by one track. Further, a discrimination signal adding circuit 17 adds said discrimination signal to a corresponding image signal. Said discrimination signal is detected during reproduction and the image signal corresponding to said signal is selected to reproduced only said signal.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The invention of this application relates to a video signal recording and reproducing method and apparatus for controlling the recording and reproducing state according to the information amount of the video signal.

(Background technology) When recording and reproducing a video signal obtained by photographing a subject using an image sensor, digital recording and reproducing is preferred over analog recording and reproducing in terms of S/N ratio, distortion, etc. that determine the quality of the reproduced image. Since the method is much better,
The digital recording and playback method has received awards.

A conventional digital recording and reproducing apparatus of this type will be described below.

FIG. 1 shows a recording device that records a video signal of a subject output from an imaging system.

In the figure, 1 is a lens system υ for converging a subject image, and 2 is an image sensor made of, for example, a solid-state image sensor. The image sensor 2 has 384 pixels in the horizontal direction and 490 pixels in the vertical direction, and color filters having a known configuration are arranged in these pixels. 3 is an AD converter that converts each pixel of the image sensor 2 to a frequency of 9.16 MHz (twice the frequency of the color subcarrier in the NTSC system).
The video signal scanned and extracted is converted into an 8-bit digital signal. Reference numeral 4 denotes a color decoder which receives the 8-bit digital signal output from the AD converter 3 and decomposes it into color signals of a luminance signal Y, an R (red) signal, and a B (blue) signal. 5 is a compression/correction code adding circuit which quantizes the prediction error value of the Sansol value of the color signal of the luminance signal Y, R signal and B signal from the color decoder 4, and converts it into a binary number sequence. In addition to performing band compression processing using pulse code modulation (DPCM), etc., an error correction code is added to the signal that has been subjected to band compression processing in order to prevent quality deterioration of the reproduced signal. Then, the luminance signal Y, R signal, and B signal, which are converted into 8-bit 7.16 MHz digital signals, are divided into 6 channels and 7.16 MHz, for example. It converts it into a digital signal. 6 is a modulator that modulates a signal suitable for recording on the record carrier; 7 is a multihead for recording on the record carrier or extracting the signal recorded on the record carrier;
In this example, the number of heads is six.

FIG. 2 shows a recording mechanism when a magnetic sheet is used as a recording carrier.

In the same figure, 7 is the multi-head shown in FIG. 1, 10 is a head moving mechanism, and this head moving mechanism 1
The multi-head 7 is attached to 0, and 9.10a is a drive section of the multi-head moving mechanism 10. Reference numeral 8 denotes a magnetic sheet, which is rotated by a sheet rotation motor 9 at a predetermined rotational speed of, for example, 180 Orpm, and a head moving mechanism 10 is moved in the radial direction of the magnetic sheet 8 at predetermined pitch intervals. A digital video signal is recorded on the magnetic sheet 8 or the recorded digital video signal is taken out from the magnetic sheet 8.

Next, the recording operation will be explained with reference to FIGS. 1 and 2.

Optical information from an object is converged by a lens system 1, photoelectrically converted and stored in each of, for example, 384 pixels in the horizontal direction and 490 pixels in the vertical direction, that is, 384H x 490V pixels, of the image sensor 2.

Then, the image information of the subject stored in each pixel is transmitted to the NTS
The video signal is scanned and extracted at a frequency of 9.16 MHz, which is twice the color subcarrier frequency of the C method, and the extracted video signal is input to the AD converter 3. The AD converter 3 digitizes the signals at the same frequency of 9 and 16 MHz, and outputs, for example, an 8-bit digital signal containing a color signal corresponding to each pixel. This digital signal is input to a color decoder 4, which decomposes the input digital video signal into a luminance signal Y and color signals of R and B signals, and these signals are input to a compression/correction code addition circuit 5. Ru. The compression/correction code addition circuit 5 performs band compression processing on the digital luminance signal Y, the digital R signal, and the B signal, and also adds an error correction code to the digital luminance signal Y and the R signal, which is the chrominance signal. The signal and B signal are output after being distributed into 6 channels using a 7.16 h signal. The signal is applied to the multihead 7 after being modulated by the modulation circuit 6, for example by modified frequency modulation (MFM) or three-position modulation (3PM), so as to be suitable for recording on a record carrier.

Then, the seat rotation motor 9 is rotated, for example, 1800 mm.
The multi-head moving mechanism 10 is fed at predetermined pitches in the radial direction of the magnetic sheet 8 while digitally recording one frame in a circumferential or spiral manner on the magnetic sheet 8 which is rotated at a predetermined rotational speed of rpm. .

The recording track pattern recorded in this manner is shown in FIG.

In the figure, six recording tracks are used in this example to record the digital video signal for one frame.
For recording the luminance signal Y, four recording tracks Y, ~Y4 are used to record and reproduce high image quality, and 16 brightness levels are recorded with 4 bits, and the color signal is One recording track C is used for recording the R signal and the B signal, and one recording track P is used for recording the error correction signal. Note that one frame of the next image is recorded in the recording track y-i' .

A video signal reproducing apparatus for reproducing digital video signals recorded on a magnetic sheet in this manner will be explained with reference to FIG.

In the figure, 11 is a demodulation circuit, and a multihead 7
The six channels of digital signals extracted are demodulated and input to the decoding and error correction circuit 12. This decoding/error correction circuit 12 decodes the band-compressed signal to which the error correction code has been added into the original digital luminance signal and R and B signals which are digital color signals. A color encoder 13 converts the decoded luminance signal, R signal, and B signal into an NTSC television signal.

14 is a DA converter which converts the input NTSC television signal into an analog signal.

The operation of the device configured in this way will be explained.

The six luminance signals recorded on the magnetic sheet 8, the color signals B and R signals, and the error correction code signal are extracted by the multihead 7 and input to the demodulation circuit 11.

Since the input signal has been modulated by modified frequency modulation (MFM), three-position modulation (3PM), etc., it is demodulated and converted into the original signal, and then input to the decoding/error correction circuit 12. Since this input signal has been band-compressed, it contains the original luminance signal Y, the R signal which is the color signal, and the B signal.
Simultaneously with signal decoding, error correction signal processing is performed. The decoded and error-corrected signal is input to the color encoder 13, where it is converted into an NTSC color television signal, which is then converted into a digital analog NTSC television signal by the DA converter I4, which is not shown. input to the playback device.

By the way, in addition to being used for normal photography, video cameras are also used to attach a DP adapter to the video camera, continuously shoot film or slide film, and edit by inserting a title image in between.

In many cases, the title picture is created by writing black characters on a white background. Create a title picture,
When photographing this with a video camera and recording or reproducing it on a record carrier using the digital method described above, the image information of the title image is expressed as a binary image of white and black.
The amount of information in one bit is sufficient, and the amount of information is much smaller than that required for recording or reproducing a normal color video signal, for example, in six recording tracks. .

However, when a title picture is photographed using the above-mentioned conventional device and recorded on a record carrier or played back, six recording tracks are used, so the disadvantage is that the recording tracks are used uneconomically. There is.

(Objective) The first invention of this application is to solve the drawbacks of the prior art, and is to efficiently use the recording tracks of a record carrier for a video signal of a halftone image or a video signal of a binary image. The second invention aims to provide a video signal recording and reproducing method for recording a video signal as a halftone image or a binary image video signal, and reproducing the recorded signal in this way. A third aspect of the present invention aims to provide a recording device that can efficiently use recording tracks depending on the situation. An object of the present invention is to provide a reproduction device that reproduces a video signal of a value image.

(Description by Example) Hereinafter, the means taken in the invention of this application to achieve the above object will be illustrated and explained with reference to the drawings. A recording device for carrying out the above method will be explained with reference to FIG. 5, a recording pattern recorded in this way is shown in FIG. do.

Components designated with reference numerals 1 to 7 in FIG. 5 have the same configuration and function as those designated by the same reference numerals in FIG. 1, so their explanation will be omitted.

No. 15 is used when the photographer shoots a normal image, that is, a half-tone image, or when shooting only two colors, such as a title image, for example, white,
A changeover switch J5 is operated when photographing a binary image represented by black, and in the first recording mode in which a halftone image is to be photographed and recorded, the changeover switch J5 is operated by the compression/correction code addition circuit 5. In the second recording mode, which is connected to the output signal terminal 15b and in which a binary image such as a title image is to be photographed and recorded, the changeover switch 15 selects the highest pitch of the digital luminance signal Y output from the color decoder 4. ) (MSB) is connected to the output signal terminal 15a from which the signal is output. The most significant bit signal of this digital luminance signal Y is a binary image video signal sliced at approximately 50% of the video signal, and is a binary image signal such as a title image.
Suitable for recording value images.

Reference numeral 16 denotes a discrimination signal generator, and at the same time when the changeover switch 15 is connected to the output signal terminal 15b or the output signal terminal 15a, the discrimination signal generator 16 starts a first signal generator for photographing and recording a halftone image. A discrimination signal generator 16 generates a discrimination signal indicating a recording mode or a discrimination signal indicating a second recording mode in which a binary image such as a title image is photographed and recorded.
gives a signal indicating the first recording mode or a signal indicating the second recording mode to the recording head moving mechanism (not shown), and after completing recording of one field in the first recording mode, starts recording of the next one field. When recording, the multi-head 7 is moved by six recording tracks, and in the second recording mode, after the recording of one field is completed, the multi-head 7 is moved by one recording track.

17 is a discrimination signal addition circuit which adds a signal indicating the first recording mode to the most significant bit of the luminance signal Y of the video signal of the halftone image, or adds a signal indicating the first recording mode to the most significant bit of the luminance signal Y of the video signal of the binary image. A signal indicating the second recording mode is added to the bit.

Note that the signal indicating the first recording mode or the signal indicating the second recording mode is one that is generated within the vertical synchronization signal generation period and added to the video signal of the halftone image or the video signal of the binary image. Therefore, during reproduction, the signal indicating the first recording mode or the signal indicating the second recording mode is not displayed on the display.

In the first recording mode, the output signal of the modulation circuit 6 is recorded on the first recording track by the multihead 7,
In the second recording mode, data is recorded on one recording track.

FIG. 6 shows a recording turn of a record carrier recorded by the recording method described above.

In the same figure, in the first recording mode, the luminance signal Y of the video signal of the halftone image is spread over four recording tracks Y-1.
-Y-4, the R signal and B signal, which are color signals, are recorded on the recording track C, and the error correction code signal is recorded on the recording track P.

In this manner, in the first recording mode, the video signal for one frame is recorded on six recording tracks. Note that the symbol ID shown on the recording track Y-1 where the luminance signal is recorded is a signal indicating that recording was performed in the first recording mode. This is added to dimension 4.

The next recording track Y-MSB is for recording the video signal of the binary image in the second recording mode, and the video signal for one frame of the title picture is recorded in this recording track Y-MSB. Ru. In addition, recording track Y-MS
The symbol ID shown in H is . In addition, Y-1'
, Y-2', . . . record a video signal for one frame of the next halftone image.

The operation of the device configured in this way will be explained.

First, when photographing and recording a halftone image, when the changeover switch 15 is switched to the first recording mode, the changeover switch 15 is connected to the output signal terminal 15b. A part of the luminance signal of the digital signal output from the compression/correction code addition circuit 5 is input to the discrimination signal addition circuit 17 . On the other hand, the discrimination signal ID indicating the first recording mode outputted from the discrimination signal generator 16 is also output from the discrimination signal addition circuit 17.
The signal is inputted to the image signal, added to the most significant bit of the luminance signal of the video signal of the halftone image, and recorded along with the video signal on six recording tracks by the multihead 7 via the modulation circuit 6 as shown in FIG. Ru.

When photographing and recording an image such as a title picture, the changeover switch 15 is switched to the second recording mode and connected to the output signal terminal 15g. The most significant bit signal of the luminance signal Y output from the color decoder 4 is input to the discrimination signal addition circuit 17 via the conductor l. Further, since the discrimination signal ID indicating the second recording mode outputted from the discrimination signal generator 16 is also input to the discrimination signal addition circuit 17,
A determination signal indicating the second recording mode is added to the most significant bit of the luminance signal of the video signal indicating the binary image, and the modulation circuit 6
As shown in FIG. 6, the multi-head 7 records the image on one recording track Y-MSH together with a binary image video signal.

Components designated with reference numerals 7, 11 to 14 in FIG. 7 have the same configuration and function as those designated with the same reference numerals in FIG. 3, so their explanations will be omitted. .

In the figure, reference numeral 19 indicates a discrimination signal indicating that the first playback mode is for playing back a video signal of a halftone image recorded on a recording track, or a first playback mode for playing back a video signal of a binary image such as a title picture. This is a discrimination signal detection circuit that detects a discrimination signal indicating that the playback mode is in No. 2 reproduction mode. This discrimination signal detection circuit 1
The luminance signal recorded on the recording tracks Y-1 and Y-MSB taken out by the multi-head 7 from the demodulation circuit 11 is input to 9 via conductive wires 11 and 13. The discrimination signal detection circuit 9 detects a signal indicating the first reproduction mode or a signal indicating the second reproduction mode added to the most significant bit of the input luminance signal, and switches the signal indicating the discrimination result. 18 and a control circuit of a multi-head moving mechanism (not shown). 18 is a switch, which selects recording tracks Y-1,
The luminance signal recorded in the Y-MSB is input through the conductors 11 and l, and the discrimination signal detection circuit 19 discriminates whether the mode is the first reproduction mode or the second reproduction mode, and adds the discrimination signal. It will be done. If the discrimination signal is a signal indicating the first reproduction mode, the switch 18 switches the demodulation circuit 11
, the signal is switched to form a normal reproduction signal processing circuit to the color decoder 13 via the decoding/error correction circuit I2 and the switch 18, and the signal indicates the second reproduction mode. , the switch 18 is switched so that a reproduced signal processing circuit is formed in which the luminance signal Y-MSB output from the demodulation circuit 1 is input to the color decoder I8 via the conductors l, , l. .

Note that the discrimination signal output from the discrimination signal detection circuit 9 is input to the control circuit of the multi-head moving mechanism (not shown) via the conductive wires 14 and 16, and the discrimination signal indicates the first reproduction mode. If the signal is
After playing back one frame, it is moved by six recording tracks and playing back the next one frame, and the determination signal is a signal indicating the second playback mode. In this case, after the multi-head 7 reproduces one frame, it is moved by one recording track and reproduces the next frame.

The regeneration effect of the device configured as described above will be explained.

The output signal extracted from the magnetic sheet by the multi-head 7 is input to the demodulation circuit 11, and the demodulated output signal is input to the decoding/error correction circuit 12. recording track Y-1 to which a discrimination signal ID indicating whether the reproduction mode or the second reproduction mode is added;
Alternatively, a signal from Y-MSB is input to the discrimination signal detection circuit 19 via conductors /1 and 13. Discrimination signal detection circuit 1
9 determines whether the mode is the first reproduction mode or the second reproduction mode from the determination signal, and the determination signal is inputted to the switch 18 via the conductors 14 and 1, and the conductor 1.

The signal is inputted to a control circuit of a multi-head moving mechanism (not shown) via. In the first playback mode, the switch 18 is switched so that the demodulation circuit 1, the decoding/error correction circuit 12, and the color encoder form a normal playback signal processing circuit. In the first reproduction mode, the decoding/error correction circuit 12 which receives the output signal of the demodulation circuit 11 decodes the band-compressed digital signal into the original signal, and further converts the luminance signal Y, R signal, The decoded signal into the B signal is input to the color encoder 13 via the switch 18.

When the signal discrimination detection circuit 19 outputs a discrimination signal indicating the second reproduction mode, the switch 18 switches the demodulation circuit 1
The luminance signal recorded on the recording track Y-MSE output from the conductor l! and a second reproduction mode input to the color encoder 13 via the switch 18 to form a reproduction signal processing circuit.

In the first playback mode, the color encoder 13 converts the input decoded signal into an NTSC color television signal, and the DA converter 14 converts it into a digital analog NTSC television signal. color encoder 1 in the second playback mode.
A binary signal is input to 3 via the demodulation circuit 11, conductors 11 and 12, and the switch 18, and is converted into an NTSC television signal.
It is converted into an SC television signal and output to a display (not shown).

Next, a video signal recording and reproducing method will be explained. When a photographer shoots and records a halftone image, he switches the changeover switch 15 to the first recording mode, and
is connected to the output terminal 15b. Simultaneously discrimination signal generator 1
6 is also energized and generates a discrimination signal indicating the first recording mode, which is input to the discrimination signal addition circuit 17. A part of the luminance signal of the digital signal output from the compression/correction code circuit 5 is input to the discrimination signal addition circuit 17, and the luminance signal is recorded via the modulation circuit 6 and the multi-head 7 as shown in FIG. A discrimination signal called ID indicating the first recording mode is recorded in the most significant bit of track y-1 together with the luminance signal of the video signal of the halftone image, and the remaining 5
Other luminance signals, color signals, and error correction code signals are recorded on the recording track of the book. When recording a video signal such as a binary image, when the photographer sets the second recording mode, the selector switch 15 is connected to the output terminal 15h, and the discrimination signal generator 16 selects the second recording mode. A discrimination signal ID indicating this is generated and input to the discrimination signal addition circuit 17. The most significant bit signal of the luminance signal Y output from the color decoder 4 is added to this discrimination signal addition circuit 17, and the second most significant bit signal is added to this most significant bit signal.
A discrimination signal ID indicating the recording mode is added thereto, and the signal is recorded by the multihead 7 via the modulation circuit 6 on the recording track Y-MSB shown in FIG.

When reproducing the video signal recorded on the magnetic sheet in this way, the signal extracted by the multi-head 7 is input to the demodulation circuit 11, and the first reproduction mode of the luminance signal of the output signal is inputted to the demodulation circuit 11. The signal of the recording track Y-1 or Y-MSH to which the discrimination signal indicating from the second reproduction mode is added is input to the discrimination signal detection circuit 19, and the discrimination signal is input to the switch 18. When this discrimination signal indicates the first reproduction mode, the switch 18 switches the demodulation circuit 1
1. A normal reproduction signal processing circuit including a decoding/error correction circuit 12 and a color encoder 13 is formed, and a reproduced video signal of a halftone image is output. When the aforementioned discrimination signal indicates the second reproduction mode, the switch 18 transmits the luminance signal recorded in the recording track Y-MSB output from the demodulation circuit 11 to the color encoder via the switch 18. A reproduction signal processing circuit is formed to input the input signal to 13, and outputs a reproduced video signal of a binary image.

(Effects) As explained above, according to the first invention of this application, a video signal of a halftone image or a video signal of a binary image is co-constructed with its discrimination signal, and is recorded by efficiently using the recording track. The video signal of the halftone image recorded in this way or the video signal of the binary image is detected together with its discrimination signal, and the reproduction signal processing system is switched in response to this to detect the halftone image. According to the second invention, there is provided a video signal recording and reproducing method for reproducing a video signal of a halftone image or a video signal of a binary image to be recorded. is extracted by the switching means and added to the discrimination signal addition means, and a discrimination signal from the discrimination signal generation means that generates a discrimination signal for recording a video signal of a half-tone image or a video signal of a binary image. According to the third aspect of the present invention, a video signal recorded together with a video signal extracted from the record carrier recorded in the above manner can be provided. Discrimination (No. A is detected by the discrimination signal detection means, the switching means is operated to switch between the video signal reproduction system for the halftone image or the video signal reproduction system for the binary image, and the video signal for the halftone image is detected. Alternatively, it is possible to provide a playback device that plays back a video signal of a binary image.

[Brief explanation of the drawing]

1 to 4 show an apparatus for implementing a conventional video signal recording and reproducing method, and FIG. 1 is a block diagram of the recording apparatus;
Fig. 2 is a perspective view of the recording mechanism, Fig. 3 is a pattern diagram of the recording tracks of the record carrier, Fig. 4 is a block diagram of the reproducing device, and Fig. 5 is a block diagram of the video signal recording device for carrying out the steps starting from Fig. 5. 6 is a pattern diagram of recording tracks recorded in this manner, and FIG. 7 is a block diagram of a video signal reproducing apparatus for reproducing the recorded signals. In the figure, 1 is a lens system, 2 is an image sensor, 3 is an AD converter,
4 is a color decoder, 5 is a compression/correction signal addition circuit, 6 is a modulation circuit, 2 is a multihead, 11 is a demodulation circuit, 12 is a decoding/error correction circuit, 13 is a color encoder, 14 is a D
A converter, 15 is a switch, 16 is a discrimination signal generator, 17
18 is a switch, and 19 is a discrimination signal detection circuit.

Claims (3)

[Claims] (1) A discrimination signal indicating whether the video signal to be recorded is a halftone image video signal or a binary image video signal is recorded on the record carrier together with the halftone image video signal or the binary image video signal. and detects a discrimination signal included in the video signal extracted from the record carrier, and performs reproduction processing of a halftone image video signal or reproduction processing of a binary image video signal according to this discrimination signal. Recording and playback method. (2) A switching means for extracting a video signal of a halftone image to be recorded or a video signal of a binary image, and generating a discrimination signal indicating whether the video signal is a halftone image or a binary image. A video signal recording device comprising: a discrimination signal generating means; and a discrimination signal adding means for adding the discrimination signal output from the discrimination signal generating means to a video signal of a halftone image or to a video signal of a binary image. (3) Discrimination signal detection means for detecting a discrimination signal indicating whether the reproduced video signal is a halftone image video signal or a binary image video signal, and a υ intermediate based on the output from the discrimination signal detection means. 1. A video signal reproducing device comprising: switching means for switching to a reproducing processing system for a video signal of a digital image or a reproducing processing system for a video signal of a binary image.