JP2641626B2 - MUSE signal recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a MUSE signal recording device such as a MUSE-VTR, and more particularly, to a MUSE signal recording device capable of recording a MUSE signal in a pseudo manner similar to an NTSC signal. Things.

[0002]

2. Description of the Related Art Hi-Vision is a completely new television system developed to meet the demand for higher image quality of television images, and has already been put to practical use in various fields including broadcasting. In response to this, development of high-vision equipment such as a receiver and a VTR has been advanced.
In the transmission of a video signal by such a high definition, M
Efficient use of the transmission band is achieved by adopting a band compression method called USE (Maltiple Sub-Nyquist Sampling Encoding) method.

By the way, a video signal (hereinafter, referred to as a MUSE signal) transmitted by the MUSE method is converted to a VTR.
When recording on a magnetic tape using a recording / reproducing device such as
The MUSE signal is configured such that a negative sync signal and a burst signal serving as a reference for time axis correction during reproduction are added to a blank period generated by time compression. Hereinafter, as an example of an apparatus for performing such processing,
The recording signal processing in the MUSE-VTR will be described.

As shown in FIG. 6, in a recording signal processing system of a MUSE-VTR, an input MUSE signal (shown in FIG. 7A) is converted into a digital MU by an A / D converter 21.
The data is converted into SE data, and from this data, the sync separation circuit 2
2, synchronous data corresponding to the synchronous signal is extracted. The MUSE data is a write clock W generated by the memory control circuit 23 based on the synchronization data.
The data is written to the line memory 24 by CK, and is read by the read clock RCK also generated by the memory control circuit 23. Since the read clock RCK has a higher frequency than the write clock WCK, the read MUSE
The data is time compressed. For example, the write clock WC
K is 16.2 MHz, and read clock RCK is 1
In case of 7.28 MHz, MUSE data is 15/1
6 compressed.

On the other hand, the negative polarity synchronization / burst generation circuit 25 generates negative polarity synchronization data serving as a negative polarity synchronization signal and burst data serving as a burst signal based on the read clock RCK. MUSE read from memory 24
And the data are selectively output by the multiplexer 26. That is, during the blank period generated by time-compressing the MUSE data, the negative sync data and the burst data are output, and the MUSE data has a form in which the negative sync data and the burst data are added.
The MUSE data is converted into an analog signal by the D / A converter 27, and as shown in FIG.
An output MUSE signal is obtained by adding a negative synchronizing signal and a burst signal to the beginning of one horizontal scanning period consisting of a time-compressed set of a color signal C and a luminance signal Y.

[0006]

However, in the above-mentioned conventional configuration, a memory control circuit 23 for generating two systems of clocks is required in order to time-compress the MUSE signal. In general, the price of the MUSE-VTR body is soared because it is expensive. Also for other circuits,
Since the MUSE signal is converted into the special format as described above, a dedicated expensive IC or the like is required, and the problem that the price of the main body of the apparatus is increased as in the above case has arisen.

[0007]

According to the present invention, there is provided a MUSE signal recording apparatus comprising at least one MUSE signal recording apparatus.
A memory means such as a frame memory having a storage capacity of a MUSE signal for a frame, and the memory means for writing a MUSE signal excluding an audio signal and for writing the MUSE signal
A memory control means for controlling a signal to be read out in one horizontal scanning period of the NTSC signal by two consecutive horizontal scanning periods, and performing writing and reading of the memory means with a clock of the same frequency; In order to convert the signal into the same signal format as that of the NTSC signal, there is provided a negative synchronizing means for adding a negative synchronizing signal to the MUSE signal read from the memory means.

[0008]

In the above arrangement, the input MUSE signal is written into the memory means for each frame and temporarily stored under the control of the memory control means. The MUSE signal written in the memory means is also controlled by the memory control means, and has the same frequency as that when the signal is continuously written by 2H in one horizontal scanning period (hereinafter, appropriately referred to as H) of the NTSC signal. Read by clock. When a negative horizontal sync signal is added to the MUSE signal as a negative sync signal by the negative sync adding means, a new 1H time width formed by being divided by the horizontal sync signal is set to NTSC.
This is the same as 1H of the signal, and the number of lines in one frame is reduced to half of the original MUSE signal.

Also, the MUSE read from the memory means
Since the signal does not include an audio signal, when a new 1H is formed as described above, the number of lines in one frame is set to NT.
Since the number of lines is smaller than that of the SC signal, a negative polarity vertical synchronizing signal is added as a negative polarity synchronizing signal by the negative polarity synchronizing means during that period, and the number of lines in one frame becomes the same as the NTSC signal.

As described above, by converting the MUSE signal into the same signal format as the NTSC signal, the MUSE signal can be handled in the same manner as the NTSC signal. Thus, a conventional NTSC signal processing IC can be used. Further, since the clock for writing and reading the MUSE signal in the memory means has the same frequency, an inexpensive circuit can be used for the memory control means for generating the clock.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment in which the present invention is applied to a MUSE-VTR will be described below with reference to FIGS.

As shown in FIG. 1, the MUS according to the present embodiment
The E-VTR includes an A / D converter 1 and an audio signal separation circuit 2
, A FIFO (First In First Out) memory 3, a synchronization separation circuit 4, a memory control circuit 5, a frame memory 6, a negative polarity synchronization / burst generation circuit 7, a multiplexer 8, and a D / A converter 9. Recording signal processing system.

The A / D converter 1 is a circuit for converting an input MUSE signal into digital MUSE data. The audio signal separation circuit 2 converts the MUSE data into 2
It is a circuit that separates the audio PCM signal of the value. FIFO
(First In First Out) The memory 3 is a memory for writing and reading out the audio PCM signal output from the audio signal separation circuit 2 in the order of writing, and is configured to be able to perform writing and reading independently. .

The sync separation circuit 4 converts the MUSE data output from the A / D converter 1 into digital data of a horizontal synchronizing signal (hereinafter referred to as horizontal synchronizing data) HD and digital data of a vertical synchronizing signal (hereinafter referred to as vertical synchronizing signal). (Referred to as data). A memory control circuit 5 as a memory control means generates various clocks and control signals based on the horizontal synchronization data HD and the vertical synchronization signal data VD, and controls the operations of the frame memory 6 and the negative polarity synchronization / burst generation circuit 7. It has become. For example, the write clock supplied to the frame memory 6 is such that a portion of the MUSE data excluding the audio PCM signal is
The pulse in the period in which the signal is provided is missing.

The read clock also supplied to the frame memory 6 has the same frequency as the write clock. However, the MUSE data written in the frame memory 6 is converted to the NTSC signal 1H of 63.5 μsec. It is formed so as to read continuously 2H at a time and not to read three lines of the NTSC signal every time almost half of the lines in one frame are read. The frame memory 6 as a memory means stores at least the MUSE data 1
This memory has a storage capacity for a frame, writes MUSE data output from the A / D converter 1 frame by frame, temporarily stores the MUSE data, and reads the MUSE data in the order of writing.

The negative sync / burst generating circuit 7 generates a negative sync signal (an additional horizontal sync signal and an additional vertical sync signal) for adding to the MUSE data based on the horizontal sync data HD and the vertical sync signal data VD. This circuit generates negative-polarity synchronization data as data and burst data as digital data of a burst signal. The multiplexer 8 is an output selection circuit that outputs the MUSE data read from the frame memory 6 and outputs the negative synchronization data and the burst data during a period in which the MUSE data is not read. The D / A converter 9 is a circuit that converts data output from the multiplexer 8 into analog data.

The circuit including the negative sync / burst generating circuit 7 and the multiplexer 8 adds the negative sync data and burst data to the MUSE data read from the frame memory 6 and converts the MUSE signal into the same signal format as the NTSC signal. It has a function as a negative electrode synchronization adding means.

Here, the operation of the above configuration will be described.

The input MUSE signal is, as shown in FIG.
1H (29.629 μsec) is sampled at 480 points at a sampling frequency of 16.2 MHz, and 11 points in the horizontal synchronizing signal (HD period in the figure) and 94 in the color signals (C1 to C1032 in the figure) in order from the top. 374 points are assigned to points and luminance signals (Y1 to Y1032 in the figure). The color signal is arranged 4H ahead of the luminance signal. Also, during the vertical blanking period, audio PCM
In addition to superimposed signals, VITS (VerticalInterv
al Test Signal), a frame pulse, a clamp level signal, a control signal, and the like. When the input MUSE signal thus configured is represented by a simplified waveform, as shown in FIG. 3A, the color signals (C _n , C
_{n + 1,} ...) and the luminance signal (in the drawing _{Y n + 4, Y n +} 5, ...) are made of, or the like.

The input MUSE signal is supplied to the A / D converter 1
Is converted into digital MUSE data by this MUS
The E data is input to the audio signal separation circuit 2, the synchronization separation circuit 4, and the frame memory 6. The audio PCM signal separated from the MUSE data by the audio signal separation circuit 2 is
Temporarily stored in the FO memory 3, the frame memory 6
And the time is matched with the MUSE data processed by the system. Further, a write clock or the like is generated from the memory control circuit 5 based on the horizontal synchronizing data HD and the vertical synchronizing signal data VD separated from the MUSE data by the synchronizing separation circuit 4, and the MUSE data is written to the frame memory 6 by these. Be included. MUSE data is
The audio PCM signal is removed when data is written to the frame memory 6 by the write clock. At this time,
It is also assumed that the blank period provided on line 564 of the input MUSE signal is not written in the frame memory 6.

MUS stored in the frame memory 6
The E data is sequentially read by a read clock output from the memory control circuit 5 and input to the multiplexer 8. In the multiplexer 8, an additional synchronization period during which MUSE data is not read from the frame memory 6 (see FIG.
(B), the negative sync data and the burst data generated by the negative sync / burst generating circuit 7 are output under the control of the memory control circuit 5, and the MUSE data is output during other periods. At this time, for example,
This means that the negative sync data and the burst data are added during the additional sync period provided at the beginning of the 2H MUSE data output continuously or for each half line of one frame. Then, the output of the multiplexer 8 is converted into an analog signal by the D / A converter 9 to obtain an analog signal.
As shown in the figure, a color signal (C _n , C _{n + 1} ,... In the drawing) and a luminance signal (Y _{n + 4} , Y in the drawing) for the input MUSE signal 2H.
_{n + 5} ,...) to which an additional horizontal synchronizing signal of negative polarity and a burst signal are added, and an output MUSE signal to which an additional vertical synchronizing signal is added, although not shown, as described later.

That is, the input MUSE signal is 2H (2
A new 1H formed by adding an additional horizontal synchronization signal every 9.629 μsec × 2) becomes the same as 1H (63.5 μsec) of the NTSC signal, and
In a state where the number of lines in one frame is reduced to half (562H) and the number of lines is reduced by removing the audio PCM signal, one frame becomes 525H by providing an additional vertical synchronization signal almost every half of one frame. , Which is pseudo-converted into an NTSC signal.

Next, the format of the output MUSE signal will be described in detail.

As shown in FIG. 4, in the output MUSE signal, the additional horizontal synchronizing signal is provided in the first 4.242 μsec period, while the 525th and 2nd lines and 2nd line
An additional vertical synchronization signal is provided on the 62nd line to the 264th line. Also, since the audio PCM signal has been removed, the color signal C that precedes the luminance signals Y1 to Y516.
1 to C4 are collectively provided in the first half of the fourth line, and C517 to 520 preceding the luminance signals Y517 to Y1032 are collectively disposed in the first half of the 265th line.

In the input MUSE signal, the color signals C6 to C516 and the color signal C522 arranged on even lines
To C1032 are arranged on the 5th to 259th lines and the 266th to 522th lines, respectively.
In the input MUSE signal, the color signals C5 to C515 and the color signals C521 to C1031, which were arranged on odd lines.
Are arranged on lines 4 to 258 and lines 265 to 521, respectively. On the other hand, input M
In the USE signal, the luminance signals Y2 to Y516 and the luminance signals Y518 to C1032 arranged on the even lines are used.
Are arranged in the 5th to 261st lines and the 266th to 524th lines, respectively.

In the input MUSE signal, the luminance signals Y1 to Y515 and the luminance signal
17 to C1031 are allocated to the 4th to 260th lines and the 265th to 523th lines, respectively.

In the input MUSE signal, the frame pulse (1 #) and VITS (1
#) And the frame pulse (2
#) And VITS (2 #) are arranged in the first half and the second half of the third line, respectively, and the clamp level signal is arranged in the second half of the 261 and 254 lines, respectively. The control signal is a color signal C515, 516,
It is arranged following lines 1031 and 1032.

The recording video signal having such a configuration is represented by F
After being M-modulated, it is recorded together with the audio PCM signal on the magnetic tape 10 by a helical scan method as shown in FIG.

To perform such recording, the magnetic tape 1
0 is wound around a drum (not shown) at an angle larger than 180 ° (for example, 210 °), the output MUSE signal is recorded in the preceding 180 ° portion of the wound area, and the audio PCM signal is recorded in other areas. Make a record. As a result, on the magnetic tape 10, the output M
The recording tracks 11 for the USE signal and the recording tracks 12 for the audio PCM signal are formed separately by the same head scanning track.

As described above, according to the present embodiment, the MUS
When the E data is passed through the frame memory 6, writing and reading are performed with a clock of the same frequency, so that the clock becomes one system and an inexpensive memory control circuit 5 can be used. . In addition, the frame memory 6 not only performs signal processing during recording, but also
It can also be used for special reproduction such as search and still. Further, the input MUSE signal is pseudo-NTS
By being converted into a C signal, the signal can be handled in the same manner as the NTSC signal, and an inexpensive IC for the NTSC signal, for example, an IC for synchronization separation or an IC for servo (drum / capstan servo at the time of recording / reproducing) is used. be able to. And
By developing this, for example, when the MUSE signal and the NTSC signal are to be recorded by the same recording device, the MUS signal
Circuits and mechanisms can be partially shared between the E signal and the NTSC.

[0031]

As described above, according to the MUSE signal recording apparatus of the present invention, the memory means having the storage capacity of at least one frame of the MUSE signal, and the memory means writes the MUSE signal excluding the audio signal. MU written
Memory control means for controlling the reading of the SE signal within two horizontal scanning periods of the NTSC signal by two consecutive horizontal scanning periods, and for performing writing and reading of the memory means with a clock of the same frequency; MUSE signal to NTS
In order to convert the signal into the same signal format as that of the C signal, a negative synchronizing signal is added to the MUSE signal read from the memory means.

As a result, the MUSE signal is converted into the same signal format as the NTSC signal.
It can be handled in the same manner as the SC signal, and a conventional inexpensive IC for the NTSC signal can be used.
Further, since the clock for writing and reading the MUSE signal is one system (the same frequency), an inexpensive circuit can be used for the memory control means.

Therefore, when the present invention is employed, there is an effect that the price of the MUSE signal recording device can be reduced by using the inexpensive circuit as described above.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a main part of a recording signal processing system in a MUSE-VTR according to one embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a format of an input MUSE signal.

FIG. 3 is a waveform diagram showing an input MUSE signal and an output MUSE signal obtained by the processing according to the configuration of FIG. 1;

FIG. 4 is an explanatory diagram showing a format of an output MUSE signal of FIG. 3;

FIG. 5 is an explanatory diagram showing a recording pattern of an output MUSE signal and an audio PCM signal on a magnetic tape when recording is performed by a MUSE-VTR according to an embodiment of the present invention.

FIG. 6 is a block diagram showing a main part of a recording signal processing system in a MUSE-VTR according to a conventional example.

FIG. 7 is a waveform diagram showing an input MUSE signal and an output MUSE signal obtained by the processing according to the configuration of FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 A / D converter 4 Synchronization separation circuit 5 Memory control circuit (memory control means) 6 Frame memory (memory means) 7 Negative electrode synchronization / burst addition means 8 Multiplexer 9 D / A converter

Claims (1)

(57) [Claims] Memory means having a storage capacity according to claim 1 wherein at least one frame MUSE signal, together with the memory unit writes a MUSE signal except the audio signal, written M
USE signal for two consecutive horizontal scanning periods in NTSC
Control to read within one horizontal scanning period of the signal; and
NT and memory control means, a MUSE signal for causing the clock of the write and read and the same frequency said memory means
A negative synchronizing means for adding a negative synchronizing signal to the MUSE signal read from the memory means so as to convert the signal format into the same signal format as the SC signal.
MUSE signal recording device.