JP2903580B2 - Digital video signal multi-channel recording and playback device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital video signal multi-channel recording / reproducing apparatus suitable for a wideband video signal.

[Summary of the Invention] The present invention provides two types of high-resolution digital video signals of a normal system alternately for each sample and in reverse order for each field.
Two digital VTRs of 4: 2: 2 system distributed to channels
, And synthesize the playback signal from this digital VTR to obtain the original high-resolution digital video signal, making the data amount of each channel equal to the current data amount of the 4: 2: 2 system, and While preventing geometric distortion of the image and loss of resolution, so that 4: 2: 2 VTR can handle it,
It can be converted into wide-angle video data.

[Prior Art] As is well known, in a conventional television standard system, 52
In either the 5/60 format or the 625/50 format, the aspect ratio of the screen is 4: 3, as indicated by the chain line in FIG.
In digital VTRs, standards are set based on this aspect ratio.

For example, in the case of a digital VTR (D-1 VTR) of a D-1 system (so-called 4: 2: 2 system) corresponding to a component video signal,
The frequency fsn of the sampling clock is set as follows, and the number of effective pixels (samples) per line of each signal is as follows.

fsn = 13.5MHz Luminance signal: 720; chrominance signal: 360 The value obtained by dividing this number of samples by the aspect ratio is the resolution of each signal (the total number of white and black included in the screen height) ).

Luminance signal: 540 lines; chrominance signal: 270 lines [Problem to be Solved by the Invention] By the way, recently, in order to enhance the viewer's sense of reality, as shown by the solid line in FIG. : 9, a wide-screen television standard has been proposed.

By the way, when the D-1 VTR is adapted to a wide-angle system having a large aspect ratio, in order to prevent a geometric distortion of a reproduced image, the time axis of the digital video signal of the D-1 system is conventionally set to the aspect ratio of the normal system. At the ratio Arn / Arw = 3/4 between the ratio Arn and the aspect ratio Arw of the wide-angle system, recording is performed by compressing
At the time of reproduction, the time axis of the reproduced digital video signal is extended at the opposite ratio Arw / Arn = 4/3 and supplied to a wide-angle receiver. In this case, there is a problem that the resolution of the reproduced image displayed on the receiver is reduced at the aspect ratio Arn / Arw = 3/4 of both types.

In order to compensate for the decrease in resolution, it is conceivable to increase the number of effective samples per line in advance.
As a method, for example, video signals are alternately sampled by a pair of sampling circuits, recorded on a recording medium in multiple channels, and multi-channel sampled signals reproduced from the recording medium are combined to form a wideband video signal. It is known to be a signal. However, when the number of effective samples is increased, the amount of data naturally increases, and
There is a problem that the 4: 2: 2 digital VTR cannot cope with the problem.

In view of such a point, an object of the present invention is to enable normal video data to be dealt with by a current 4: 2: 2 digital VTR while preventing geometric distortion and a decrease in resolution of a reproduced image. In addition, the video data can be converted into wide-angle video data. It is an object to provide a multi-channel recording / reproducing apparatus for digital video signals.

[Means for Solving the Problems] The present invention comprises a luminance signal and a pair of color signals, and the number of horizontal pixels is twice the number of pixels of a standard 4: 2: 2 digital component video signal. A digital video signal multi-channel recording / reproducing apparatus for recording / reproducing a high-resolution video signal having a screen aspect ratio of 9:16, wherein the high-resolution video signal Sa is alternately transmitted for each pixel to a pair of transmission paths. In addition to distributing, this distribution order is reversed for each field and transmitted.
Each of the distributed video signals Sb and Sc transmitted through a pair of transmission paths is recorded by a separate standard 4: 2: 2 digital component video tape recorder (3) or (4). This is a digital video signal multi-channel recording / reproducing apparatus that reproduces a distributed video signal to obtain a pair of reproduced video signals, and combines the pair of reproduced video signals to obtain an original high-resolution video signal Sd.

[Operation] According to this configuration, the video data of the normal system can prevent the geometric distortion of the reproduced image and the decrease in resolution while preventing
It is converted to wide-angle video data so that it can be handled by the current 4: 2: 2 digital VTR.

Embodiment An embodiment of a digital video signal multi-channel recording / reproducing apparatus according to the present invention will be described below with reference to FIGS. 1 to 4.

 FIG. 1 shows the configuration of an embodiment of the present invention.

In FIG. 1, a component video signal Sn captured by a normal camera (1N) passes through a recording system (10) from a terminal IN, and is connected to two 4: 2: 2 digital VTRs (3).
Distributed to (4) and recorded respectively. This VTR
The video signals reproduced from (3) and (4) are combined in the reproduction system (20) and supplied from the terminal OUT to the wide-angle receiver (2W) to display a reproduced image.

A required control signal is supplied from the control system (30) to the recording system (10) and the reproduction system (20).

In the recording system (10), a terminal is provided by an AD converter (11).
The analog component video signal Sn from IN is digitized, and this digital component video signal Sa is supplied to the movable contact of the distribution switch (12) to form two-channel digital component video signals Sb and Sc. Both video signals Sb and Sc are supplied to D-1 VTRs (3) and (4) via a time axis compression circuit (13).

In the playback system (20), contrary to the recording system (10), the VTR
From (3) and (4), two-channel time-axis-compressed digital component video signals are reproduced and supplied to both movable contacts of a synthesizing switch (22) through a time-axis expansion circuit (21), respectively, to synthesize. A component video signal Sd is formed. This video signal Sd is converted again into an analog component video signal by the DA converter (23).

From the terminal CK of the control system (30), a clock of the frequency fsn for a normal digital component video signal is input to a doubler (3
Via 2), it is supplied to a phase dividing circuit (32) such as a T flip-flop, and also to an AD converter (11) and a DA converter (23), respectively. The positive and negative phase outputs Q, of the phase division circuit (32) are supplied to both movable contacts of the changeover switch (33), and the output of the switch (33) is used as a changeover control signal as a changeover control signal to the distribution switch (12). Each is supplied to the synthesizing switch (22). The switch (33) is supplied with a switching control signal of the field frequency fv.

Next, the operation of the embodiment of the present invention will be described with reference to FIGS.

In the AD converter (11), the frequency fsh is equal to the normal frequency fsn.
As shown in FIG. 2A, the analog component video signal Sn is changed to a normal 2
Digital component video signal sampled at twice the density
The video signal Sa is converted to Sa and supplied to the distribution switch (12). The number of effective samples per line of the video signal Sa is as follows.

Luminance signal: 1440; Chrominance signal: 720 On the other hand, in the case of an odd field, the changeover switch (33) is in a connection state shown by a solid line in FIG. 1, for example. The positive-phase output Q of 32) is supplied to the distribution switch (12). This allows
The connection state of the switch (12) is as shown by the solid line when the positive-phase output Q is "1", and is switched as shown by the broken line when it is "0", and the connection state of the digital component video signal Sa is changed. Each sample is alternately distributed to both fixed contacts of the distribution switch (12), as shown in FIGS.
Two-channel digital component video signals Sb and Sc are formed.

In the case of an even field, the changeover switch (3
3) is in a connection state indicated by a broken line, for example, and the connection state of the switch (12) is the first state when the reverse-phase output is “1”.
As shown in the figure by a solid line, when it is "0", switching is performed as shown by a broken line.

Thereby, the data amount of the video signals Sb and Sc of each channel becomes equal to the data amount of the conventional 4: 2: 2 system, and each can be dealt with by the current digital VTR.

In addition, the order of distributing each sample of the video signal Sa to the two-channel video signals Sb and Sc is reversed according to the odd / even of the field.

In the time axis compression circuit (13), as shown in FIGS. 3A and 3B, the time axes of the two-channel video signals Sb and Sc are each compressed to, for example, 3/4, and the time axis compressed video signal Is the current 4: 2: 2 digital VTR (3),
Each is recorded in (4).

The time-axis compressed video signals of two channels reproduced from the VTRs (3) and (4) are passed through a time-axis expansion circuit (21).
As shown in FIGS. 3B and 3C, the time axis is expanded, for example, by 4/3 times. Thereby, the time axis extension circuit (21)
Can obtain a two-channel video signal corresponding to a wide-angle receiver, but as described above, the resolution of each video signal has the following low value.

Luminance signal: 405 lines; chrominance signal: 202 lines The synthesizing switch (22) is switched by the output of the phase division circuit (32) in the same manner as the distribution switch (13). 2), each sample of the 2-channel low-resolution video signal supplied to each fixed contact is alternately derived from the movable contact of the synthesizing switch (22) as shown in FIG. 2D, and is shown in FIG. As with the digital component video signal Sa, a high-resolution composite component video signal Sd is formed.

When the composite video signal Sd is supplied to the wide-angle receiver (2W) via the DA converter (23), the resolution of each signal is obtained by dividing the number of effective samples per line by the aspect ratio. The result is as follows, which is much higher than the above value of a normal 4: 2: 2 digital VTR.

Luminance signal: 810 lines; chrominance signal: 405 lines In this embodiment, two channels of the original high-resolution digital video signal Sa formed by reversing the distribution order according to the odd / even of the field. Video signal S
b and Sc are recorded on two digital VTRs, and samples of the two-channel video signals reproduced from the two digital VTRs are alternately taken out to synthesize a high-resolution digital video signal Sd.

As a result, on the playback screen, as shown in FIG. 4, the arrangement order of the samples of the video signal Sa in the video signals Sb and Sc of the two channels between the two adjacent lines is reversed, and the return ( When the phase of the aliasing is reversed and only the VTR of one channel is reproduced, the wraparound of the color signal of the still image is inconspicuous.

In the above-described embodiment, the data amount of each channel is made equal to the data amount of the 4: 2: 2 system by distributing the high-resolution digital video signal having a large data amount to two channels, and the data amount of each channel is equal to the current digital VTR. To be able to deal with it.

As a digital video signal having a large amount of data, a so-called 4 × 4 (4: 4: 4: 4) in which a luminance signal, a pair of color difference signals, and a key signal for a special effect have the same wide bandwidth, respectively.
Although a digital VTR of the system has been proposed, the present invention can be applied to the video signal of the 4 × 4 system in the same manner as described above, and the same effect can be obtained.

In this case, the luminance signal and the key signal are separately provided as D-
In addition to the distribution to one VTR, it is preferable that each pixel of the pair of color difference signals is alternately distributed to two VTRs in the same manner as described above.

[Effects of the Invention] As described above in detail, according to the present invention, a high-resolution digital video signal of a normal system is alternately output for each sample by one.
4: 2: 2 distributed to two channels in reverse order for each field
Since the original high-resolution digital video signal is obtained by recording the signals on two digital VTRs and synthesizing the playback signals from these digital VTRs, the data amount of each channel can be reduced to the current 4: 2: 2 format. The video data of the normal format can be handled by 4: 2: 2 VTR while preventing the geometric distortion of the playback image and the reduction of the resolution while preventing Thus, a multi-channel digital video signal recording / reproducing apparatus which can be converted into video data of a digital video signal can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of a multi-channel digital video signal recording / reproducing apparatus according to the present invention, FIG. 2 is a waveform diagram for explaining the operation of an embodiment of the present invention, and FIG. FIG. 4 is a time chart for explaining the operation of one embodiment of the present invention, FIG. 4 is a conceptual diagram for explaining the operation of one embodiment of the present invention, and FIG. 5 is a diagram for explaining the present invention. It is. (1N) is a normal camera, (2W) is a wide-angle receiver, (3) and (4) are digital VTRs, (11) is an AD converter, (13) is a time axis compressor, 21) is a time axis expander,
(23) is a DA converter, (31) is a frequency doubler, (3)
2) is a phase division circuit.

Claims (1)

(57) [Claims] An image signal comprising a luminance signal and a pair of color signals, the number of horizontal pixels is twice the number of pixels of a standard 4: 2: 2 digital component video signal, and the aspect ratio of the screen is 9: 2. 16. A digital video signal multi-channel recording / reproducing apparatus for recording / reproducing a high-resolution video signal of 16. The high-resolution video signal is distributed to a pair of transmission lines alternately for each pixel, and the distribution order is changed. The distributed video signals transmitted through the pair of transmission lines are recorded in the above-mentioned separate 4: 2: 2 digital component video tape recorder, and are recorded. A plurality of channels of digital video signals, wherein each of the distributed video signals is reproduced to obtain a pair of reproduced video signals, and the pair of reproduced video signals is synthesized to obtain an original high-resolution video signal. Recording and playback device.