JPH0752965B2 - VTR 3D special playback device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to special reproduction of electronic stereoscopic video (still,
Throw, strobe etc.)

<Outline of the Invention> The present invention provides an electronic stereoscopic image using binocular parallax in a VTR,
It enables stereoscopic playback even in special playback such as still, slow, and strobe.

<Prior Art> FIGS. 2 and 3 explain a mechanism of still reproduction of a general analog VTR. Figure 2 shows
This is an example of a head arrangement of a four-head system, which comprises normal recording and reproducing heads A and B having different azimuth angles and special reproducing heads A ₁ and A _{2 having} different azimuth angles.

When still reproduction is performed, as shown in FIG. 3, the tape running is stopped, the tape tension is changed, and the same track is alternately traced by the special reproduction heads A'and A ". A still image is obtained by continuously extracting the image.This method is called field still.

On the other hand, FIG. 4 illustrates slow reproduction. In slow playback, first, heads A ', A "as shown in Fig. 4A).
1 field (track A ₁ ) is reproduced still, and then heads A and B perform normal reproduction of 1 frame (track A ₁ A ₂ ). Then, again, by continuing the operation of performing the field (track A ₂ ) still reproduction with the heads A ′ and A ″, a signal as shown in FIG. 4B) is taken out and the slow reproduction is performed. Called the field throw.

Recently, there is a digital VTR that has a field memory for special playback, and the special playback mechanism is different from the analog VTR, but as a result, still and slow are performed in units of one field. Has been.

<Problems to be Solved by the Invention> As described above, in the conventional device, since the special reproduction configuration screen has one field, one frame, that is, two
When special reproduction is performed on a stereoscopic video in which one set of fields is used as an image unit, only one field (left or right image) is reproduced, and still or slow reproduction cannot be performed in stereo. Further, even if it is possible, it is difficult to accurately reproduce a stereoscopic image.

<Means for Solving Problems> Therefore, the present invention uses two sets of field memories used in a model called a digital VTR recently, and a left and right image (even / odd field) determination circuit for this and a stereoscopic image. , And special playback type (still, slow, strobe, etc.)
A stable three-dimensional special reproduction is enabled by a mode control circuit that controls the capturing of the video signal and the like in accordance with the above.

<Function> Special reproduction of stereoscopic images can be performed accurately and stably for a long time.

<Example> Hereinafter, description will be given based on an example.

FIG. 1 is a block diagram of this device.

In this figure, reference numeral 1 is a signal processing circuit, which is mainly used to generate a reference clock which is a source of a clock of a digital circuit section (a sampling clock of an A / D converter, etc.) from a video signal, and a synchronization signal separation / D converter pre-processing (such as band limitation). 2 is a field determination circuit that determines the left and right screens that are important for stereoscopic images. 3
Is a special playback type (still, slow, strobe, et
c.) A circuit for controlling a series of patterns for capturing and reading a video signal, 4 is an A / D converter, 5 and 6 are field memories for storing left and right signals respectively, 7
Is a circuit for controlling the timing of memory refresh and other memory write / read by signals from the mode control circuit, 8 is a circuit for alternately reading the contents of the memory and controlling SW2 for reconstructing one frame, 9
Is a D / A converter that converts the digital signal read from the memory back to analog.

Next, the operation will be described. First, the video signal reproduced from the magnetic tape enters the signal processing circuit 1 and the field determination circuit 2. The signal processing circuit performs system reference clock generation, synchronization signal separation, and signal preprocessing for A / D conversion. On the other hand, in the field determination circuit, the even / odd field of the signal is determined and the pulse is output to the mode control circuit 3.
Send to. In response to this, the mode control circuit 3 stores the video signal digitized by the A / D converter 4 in the field memory A5 for the left signal and in the field memory B6 for the right signal. And a signal to the memory controller 7. At the same time, the type of special reproduction (still, slow, strobe, etc.) is determined. For example, in the case of still, an odd field or an even field is continuously detected. Therefore, it is determined that the still mode is set at this time. The video signal of the stereoscopic still image is output by repeatedly reading the video that was written last without writing a new signal to the field memory.

Also, for example, in the case of slow, the odd field or the even field continues multiple times, and the opposite field continues the same number of times, so at this time, it is determined that the slow mode is set and the video signal immediately after the odd-even field is switched A video signal of a stereoscopic slow image is output by writing in the field memory and repeatedly reading the last written video without writing a new signal in other periods.

In this way, the stereoscopic video signal stored in the field memories A and B is processed by the mode control circuit according to the special reproduction type pattern (for example, in the case of stills, the field memories A and B are used).
The contents of are read out alternately and continuously. If it is slow or strobe, the same operation as still is performed until the next signal is written in the memory. ), The memory controller and the synchronous control circuit 8 for controlling SW2 for reconfiguring the video signal (to configure one frame) are controlled so as to read. Then, after that, it is returned to an analog signal by the D / A converter 9 and output as a special reproduction signal of a stereoscopic image.

<Effects of the Invention> As described above, according to the VTR stereoscopic special playback device of the present invention, the special playback mode can be automatically detected by determining whether the field of the stereoscopic video signal is odd or even. Since the write / read timing of the memory can be optimally controlled, the special reproduction of the stereoscopic video signal can be performed accurately and stably.

[Brief description of drawings]

FIG. 1 is a block circuit diagram of a stereoscopic special playback device of the present invention,
FIG. 2 is a head layout diagram of a rotary head used in a conventional analog VTR, FIG. 3 is a diagram showing a head trace state on a tape in the conventional VTR, and FIG. 4 is a head trace during slow playback in the conventional VTR. It is a figure which shows a state and an output signal.

Claims (1)

[Claims] 1. An A / D converter to which a composite video signal of a stereoscopic image reproduced from a magnetic tape of a VTR is input, and a first switch to which a digital video signal output from the A / D converter is input. A first and second field memory separately connected to two outputs of the first switch, and a second switch to which output signals of the first and second field memories are separately input. A D / A converter for converting a digital video signal output from the second switch into an analog video signal, a field determination circuit to which the composite video signal is input, and an output of the field determination circuit and A mode control circuit that outputs a switching control signal for controlling the switching of the first switch, and an output of the mode control circuit is input and the second A synchronous control circuit for outputting a switching control signal of the switch, the three-dimensional special reproduction apparatus of a VTR comprising a memory controller for controlling writing and reading of said first and second field memories in response to an output of the mode control circuit.