JPS6363293A - Special reproduction circuit - Google Patents

Abstract

PURPOSE:To reproduce a special reproduction screen by demodulation by restructuring a prescribed muse signal with a new, current control signal and a video signal even if a control signal is omitted and subsample phase information is distorted by the special reproduction of a muse signal. CONSTITUTION:A reproduction signal from a VTR is inputted to a terminal 1 and A/D-converted. A write signal W from a write control circuit 5 writes 4n one-field signals (marked with O) in a non-field memory 6. If the reproduction signal is omitted, an omission detection signal from the VTR is inputted to a terminal 2 to stop the signal W, and information written previously in a field remains unupdated in the omission part. A subsample signal decision circuit 4 detects and discriminates a phase, and a control signal generator circuit 8 generates a subsample phase showing the prescribed order of muse signals and a signal including information on all moving picture modes. A signal R from a read control circuit 7 outputs the video signal to a cut piece (a) in a switch 9 from the one-field memory 6. Timings for these outputs are connected to a cut piece (b) in the switch 9 with the aid of a timing signal from the circuit 4, and in synchronization with the timings the control signal is outputted from the generator circuit 8, thereby restructuring the muse signal.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) This invention relates to a transmission system having a control signal for transmitting image content information in addition to an image signal, such as a MUSE (MtJSE) signal. The present invention relates to a special playback circuit that performs special playback of a medium on which a signal having a signal format is recorded at a speed other than the normal speed.

(Prior art) Figure 3 shows a conceptual diagram of the basic muse signal. The muse signal consists of 4 fields in one screen, and here, the constituent fields are 4n, 4.
It is distinguished by n+1.4n+2.4r++3, and on the drawing,
O1△ and 02 are not shown as pixel values of the field. The pixel positions of the winter field are arranged as shown in the reproduced image by the Muse Bucoder in Mew 14g in the figure.
As shown in this issue, it depends on the content of the control signal located at the beginning of each field (actually included in the last part of the previous field). The content of this control is to perform a 90° phase shift for each field, and if the control signal is omitted or the order is out of order, correct demodulation will not be performed.

Figure 4 shows the head trace pattern when special playback is performed on a VTR (video tape recorder) that records using the helical scan method.
al, bl, a2, and b2 indicate tracks at the time of recording, and during normal playback, the data is traced along these tracks. In this example, if one field is recorded on one track, playback is performed at double speed. The signal currently recorded on this track is the muse signal, 1
It is assumed that one field is recorded on a track, and a control signal is contained in the shaded area in the figure.

If you turn it over, at the time of writing '81, it will be displayed for each track as shown in the figure.

A control signal whose phase is inverted from that of R is recorded. When this signal is played back at double speed, Pl appears in spots.

Since reproduction is performed in the order of P2, if such special reproduction is performed, the phase order of the control signals will be out of order.

If the subsample phase of the control signal goes out of order when demodulating the muse signal, the positions of the reproduced pixels will not be correctly arranged. Furthermore, during demodulation, the number of pixels is increased by interpolation J from between the reproduced pixels, so the screen cannot be reproduced unless the relationship between the subsample phase of the control signal and the video signal is properly aligned. Also, demodulation 5I! ! When processing is performed in still image mode, the number of pixels is increased by performing the above interpolation from the pixel information of four fields, so during special playback where information spanning multiple fields becomes a single field signal, the reproduced image may be confused. I'll let you.

(Problems to be Solved by the Invention) The present invention has been made in view of the fact that in the prior art, the phase of the control signal goes out of order during special playback, which confuses the reproduced image. The purpose of this invention is to provide two special playback circuits that can realize special playback of the Musim.

[Komyo no II4 configuration] (Means for solving the problem) In order to achieve the above object, the present invention includes a memory in which one field or two fields of specially reproduced muse signals are stored, and a memory in which one field or two fields of specially reproduced muse signals are stored. A write control circuit that writes the muse signal and stops the recording operation in the portion where the reproduced signal is missing due to interlaced scanning of the trunk, and detects sub-sample phase information in the control signal of the specially reproduced muse signal. a subsample signal discrimination circuit, a control signal generation circuit that generates a control signal having an accurate subsample phase by adding →knob→non-pull phase information from the subsample signal discrimination circuit, and a signal written in the memory. and a circuit for changing the sub-sampling phase of the control signal matched with the signal read from the memory in a predetermined format using the read control circuit. This is a characteristic feature.

(Function) By the above-mentioned means, the present invention replaces the incorrect rib sample phase information with a control signal having an accurate rib sample phase when a muse signal is specially reproduced, and further internalizes the video signal in accordance with the phase position. Adjust the numbers by inserting. Furthermore, the mode selection bits of the control signal are all set to the moving image mode, so that interpolation processing during demodulation is performed using only one field of signals. In addition, when partial pixel information is missing due to skipping playback of multiple tracks due to special playback, such as during recording/playback with a helical scan VTR, the write processing of the field memory used for signal processing is performed only on that part. ? The pixel information of the previous field is used instead.

During special playback of the muse signal, even if the control signal is missing or the sub-sample phase information is disturbed, the specified muse signal will be reconstructed using the new correct control signal and the video signal, and the special playback screen will be regenerated by demodulation. can be realized.

(Embodiment) FIG. 1<aL(b) shows the configuration of an embodiment of the present invention and a conceptual diagram of pixel arrangement during demodulation by its processing. This embodiment is an example realized by being included in a time axis correction circuit.

The muse signal specially reproduced by the VTR is inputted from the terminal 21 and converted into a digital signal by the A/D converter 23. Then, by demodulation, the four fields (4 fields) that make up one screen are
n.

4n+1.4n+2.4n+3), 4n.

4n+1 fields are stored in the 2 field memory 26. At this time, when a signal missing signal such as dropout is input from the terminal 22, the writing signal W is stopped by the write-in control circuit 25, and updating of the address information of the missing pixel portion is stopped.

Simultaneously with this writing process, the input signal is also input to the subsample signal discrimination circuit 24 to detect correct subsample phase information. Then, the timing of generating the control signal, the timing of reading out the video signal, the control signal, the direct readout signal, and the interpolation readout signal are switched to control the timing of correct succession. In response to this timing signal and sub-sample phase information, the control signal generation circuit 28 sends the correct sub-sample phase information and a control signal indicating the full video mode, and the switch 29 is synchronously connected to the section e. Then, a control signal is sent to a predetermined position of the muse signal. The image information is a readout signal R sent from the readout control circuit 27.
is read out from the 2-field memory 26 by
At this time, if the sub-sample phase of the generated control signal and the phase of the read video signal are equal, the video signal is sent out as it is by connecting the switch 29 to the section d. When the phases are different, the interpolation sieve circuit 30 calculates the pixel value at the position that fills the gap between the readout signals by interpolation, and the result is filtered a1 from the intercept C of the switch 29. These signals become the predetermined format of the muse signal, and the D/A
The signal is converted back to an analog signal by the converter 31 and output from the terminal 32.

Through the above processing, the pixel configuration of the demodulated MUSE signal is 4n and 4n+ as shown in the conceptual diagram of FIG. 1(b).
1 field'@ information is reproduced as is, 4n+2
．． Regarding the information of 4n+3 fields, 4n+2 fields are calculated by interpolating 4n fields, and 4n+3 fields are calculated by interpolating 4 days+1 fields.

Next, a second example of realizing the present invention with a smaller circuit configuration is shown.
Shown in Figure (a). This example is also an example in which the time axis correction circuit is built in, but the field memory is realized by one field. The VTR playback signal is input from terminal 1, and the A/
It is digitally converted by the D converter 3. Write control circuit 5
One field of signal 4n is generated by the write signal W from
(O mark) is written into the 1-field memory 6. However, as in the previous example, for the portion where the playback signal is missing, the loss detection signal sent from the VTR is input from terminal 2, the write signal W is stopped, and the portion is
Information in previously written fields remains without being updated.

At the same time that the digitized playback signal is stored in the memory 6, the subsample phase is detected and determined by the subsample signal discrimination circuit 4, and the overall processing operation timing and control signal to be generated are determined. will be carried out. In response to this instruction signal, the control signal generating circuit 8 generates a control signal having information on the sub-sampling phase of the mu 113 in a predetermined order and the moving picture mode. Further, the video signal is outputted from the 1-field memory 6 to the switch a of the switch 9 in response to the readout signal R of the readout control circuit 7. These output timings are controlled by a timing signal from the sub-sample signal discrimination circuit 4 so that both signals are not output simultaneously, and a switch 9 is connected to the cutter at a predetermined position of the muse signal, and a control signal is generated in synchronization with this. By being outputted from the circuit 8, the muse signal is reconfigured, converted back to an analog signal by the D/A converter 10, and outputted from the terminal 11.

In this embodiment as well, the output signal may be interpolated as in the previous example, but interpolating one field of information into four fields would result in a large scale, so the interpolation process is not performed here. An example of not doing this is shown below.

A conceptual diagram of the output signal with this configuration is shown in FIG. 2(b). As shown in the figure, all 4n field signals are substituted. Therefore, although the resolution is inferior to the above-mentioned example, the configuration can be significantly simplified.

[Effects of the Invention] As described above, according to the present invention, the helical scan V
Since a predetermined muse signal can be output even when performing special reproduction of a muse signal using a TR or the like, special reproduction of a muse signal can be realized. Furthermore, the present invention can be applied to signals having a format similar to that of the muse signal.

[Brief explanation of drawings]

FIG. 1 is a configuration explanatory diagram showing one embodiment of the present invention, FIG. 2 is a configuration explanatory diagram showing another embodiment of the present invention, FIG. 3 is a conceptual diagram of +I41Jy of the muse signal and demodulation, and FIG. The figure is a conceptual diagram of special playback (fast-forward playback) in a helical scan VTR. 3.23... A/D converter, 4, 24... Sample @ number discrimination circuit, 5, 25... Write control circuit, 6.
...1 field memory 1.7.27...Reading control circuit, 8, 28...Control signal generation circuit, 1
0.31...D/A converter, 30...Interpolation circuit. Applicant's representative, Bentanushi Taketei Suzue□□-"

Claims (1)

[Claims] 1 field or 2 of specially reproduced muse signal
a memory in which fields are stored; a write control circuit that writes a muse signal into this memory and stops the write operation for portions where the reproduced signal is missing due to track interlace scanning; and the specially reproduced muse signal. a subsample signal discriminator that detects subsample phase information in a control signal; and a control signal generator that generates a control signal with an accurate subsample phase by adding the subsample phase information from the subsample signal discriminator. a readout control circuit that sequentially reads out the signals written in the memory; and a readout control circuit that changes the subsample phase of the control signal included in the signal read out from the memory into a predetermined format. A special regeneration circuit characterized by comprising a circuit.