JP2003289510A - Video signal processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a sense of non-smoothness which occurs when reproducing a 2-3 pull-down interlace signal at a variable speed. <P>SOLUTION: A reproducing speed is detected by a reproducing speed detecting part 2, a 2-3 pull-down phase reference position of the 2-3 pull-down interlace signal recorded on a recording and reproducing medium 1 is detected by a 2-3 pull-down reference position detecting circuit 3 and based upon both the detection outputs, a control signal for write/read or the like to be supplied to a buffer memory 5 is produced by a memory control circuit 4. Then, an output signal is obtained by varying the number of redundant fields of a video signal. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video signal processing suitable for variable speed reproduction of an interlaced television video signal converted from a movie film or the like by 2-3 pulldown conversion processing and recorded on a recording / reproducing medium. Regarding the device.

[0002]

2. Description of the Related Art There is a 2-3 pull-down conversion system as a technique for converting a movie film or the like into a television image signal. This 2-3 pull-down conversion converts a signal consisting of 24 frames per second such as a motion picture film into 60 per second.
It is a method of converting into a field interlaced television video signal.

The 2-3 pulldown conversion method will be described below with reference to FIG. With the 2-3 pulldown conversion method,
The first one of the frames of the movie film shown in FIG.
An image of a frame, for example, frame A, is made to correspond to two fields of the interlace signal shown in FIG. 1B, for example, fields F1 and F2, and an image of the next frame, for example, frame B is interlaced. 3 fields, for example, fields F1, F2, F1 are repeated, and this is repeated every 1/12 seconds. That is, 2 frames (2/24 seconds) of a signal such as a movie film are made to correspond to 5 fields (5/60 seconds) of an interlaced television video signal and processed as one sequence.

The video signal thus converted is converted into 2
-3 pull-down interlaced signal.

Here, the detection of the 2-3 pulldown phase is to detect which phase of the 2-3 pulldown the recorded image is. This 2-3 pull-down phase detection is, for example, a method of detecting a difference between fields by generating one frame as 2 fields / 3 fields, and determining whether they are the same frame image or 2-3.
There is a method of detecting a sequence of 5 fields by a time code value of 30 Hz accompanying the pull-down interlaced signal.

[0006]

As shown in FIG. 9, the interlaced signal which has been subjected to the 2-3 pull-down conversion has two fields, that is, 1/24 second of one frame of film, that is, 2/2.
The case of 60 seconds and the case of 3 fields, that is, 3/60 seconds alternately exist, and there is non-linearity in the frame time axis direction.

Therefore, when the 2-3 pulldown interlaced signal is recorded on a recording medium and the signal is reproduced at a variable speed, the number of redundant frames is increased or decreased, and the 2-3 pulldown sequence is broken. A noticeable uneven number of redundant fields may occur.

FIG. 10 shows an output signal when a 2-3 pull-down interlaced signal is recorded and reproduced at a variable speed. FIG. 10A shows 1 × speed reproduction (normal reproduction) and FIG. Is 0.5 times speed reproduction, and (c) and (d) in FIG.
The output signals in the case of 25 × speed reproduction are shown respectively.

When reproduced at 0.5 times speed, it is originally 1 /
What should be a constant speed motion of 24 frames per second is an uneven number of redundant fields as shown in FIG. 7B, that is, for frame A, the number of fields is 4
On the other hand, for the frame B, the number of fields is 6, and therefore the image changes every 4/60 seconds or 6/60 seconds. Therefore, for example, an object that should move at a constant speed becomes an image in which the speed changes every 4/60 seconds or 6/60 seconds, and the motion looks visually jerky.

When reproducing at 1.25 times speed, A
Depending on the state of T (auto tracking), the pattern mainly has one of different redundant field numbers as shown in FIG. 7C or FIG.
If it becomes, 1 / similar to the playback at 0.5 times speed,
The image changes every 60 seconds or 3/60 seconds, and it usually looks more jerky than the 1x speed 2-3 pulldown image, and there is a problem that the viewer feels uncomfortable. It was

Further, in such a variable speed reproduction, the 2-3 pulldown sequence is broken as described above, and thus the 2-3 pulldown phase detection method described above does not work effectively. It is also difficult to perform inverse 2-3 pulldown conversion as shown in FIG. 11 in which the signal at the time of variable speed reproduction of the 3 pulldown interlaced signal is inversely converted into an image signal of 24 frames per second such as a movie film.

The present invention has been made in view of the above points, and the 2-3 pulldown sequence is broken when the medium on which the 2-3 pulldown interlaced signal is recorded is played back at a variable speed. The main purpose is to reduce the visual jerky feeling caused by
An object of the present invention is to enable generation of an inverse 2-3 pulldown signal from a signal at the time of 2-3 speed pulldown interlaced variable speed reproduction.

[0013]

In order to achieve the above object, the present invention is configured as follows.

That is, the video signal processing device of the present invention is
The first frame of the film of 24 frames / sec is set to 2 fields, the second frame is set to 3 fields, and 5 frames are repeated for 2 frames of film, and 24 frames are converted to 60 fields by the 2-3 pull-down method. A video signal processing device for outputting an interlaced video signal by reproducing a recording / reproduction medium having an interlaced video signal recorded thereon at a variable speed, wherein the interlace video signal reproduced from the recording / reproducing medium has a 2-3 pull-down phase. Phase reference position detection means for detecting the reference position, and control means for controlling the number of redundant fields of the interlaced video signal to be output in the direction of equalization based on the detected phase reference position and reproduction speed are provided. There is.

Here, the direction in which the number of redundant fields is made uniform includes, of course, the case where the number of redundant fields is controlled to be uniform, and the case where the number of redundant fields is controlled to be close to even if not uniform. It is a waste.

The redundant field means a field corresponding to an image of the same frame. Therefore, to make the number of redundant fields uniform makes the number of fields of the frame A and the number of fields of the frame B uniform, for example. Say that.

According to the present invention, when the recording / reproducing medium in which the 2-3 pulldown interlaced video signal is recorded is played back at a variable speed, 2 of the interlaced video signals to be played back are reproduced.
Since the reference position of the -3 pull-down phase is detected and the number of redundant fields of the interlaced video signal to be output is controlled to be uniform based on the detected phase reference position and the reproduction speed, the number of redundant fields is not adjusted. It is possible to reduce the visual jerky feeling caused by the evenness.

Further, even when the 2-3 pulldown sequence is broken during variable speed reproduction, the number of redundant fields is controlled so as to be equalized, so that the interlace in which the number of redundant fields is equalized is controlled. It is also possible to generate an inverse 2-3 pulldown signal from the video signal.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A video signal processing apparatus according to claim 1 of the present invention uses a film of an image of 24 frames / sec. In which the first frame is for two fields and the second frame is for three fields. It is a video signal processing device which outputs a interlaced video signal by variable speed reproduction of a recording / reproducing medium in which an interlaced video signal converted by the 2-3 pulldown system, which converts 24 frames into 60 fields by repeating 5 fields per. And a phase reference position detecting means for detecting a reference position of 2-3 pulldown phase of the interlaced video signal reproduced from the recording / reproducing medium, and an interlace for outputting based on the detected phase reference position and reproduction speed. And a control means for controlling the number of redundant fields of the video signal to be equalized, and the interface converted by the 2-3 pull-down method is provided. When variable speed reproduction is performed on a recording / reproducing medium in which a source video signal is recorded, a reference position of 2-3 pulldown phase of an interlaced video signal to be reproduced is detected and based on the detected phase reference position and reproduction speed. Since the number of redundant fields of the output interlaced video signal is controlled to be uniform, the visual jerky feeling due to the uneven number of redundant fields can be reduced, and the number of redundant fields can be reduced. It is also possible to generate an inverse 2-3 pull-down signal from an interlaced video signal with a uniformed signal.

According to a second aspect of the present invention, in the first aspect of the invention, the phase reference position detecting means is recorded on the recording / reproducing medium and reproduced from the recording / reproducing medium.
The phase reference position is detected based on the 3 pulldown phase reference position signal, and the control means includes a memory control circuit for controlling writing / reading of the interlaced video signal to be reproduced to / from the memory. During variable speed reproduction, the 2-3 pulldown phase reference position signal recorded on the recording / reproducing medium can be reproduced at variable speed to easily detect the reference position of the 2-3 pulldown phase. The number of redundant fields can be made uniform or close to uniform by controlling the writing or reading of the interlaced video signal reproduced at a variable speed from the reproduction medium to the memory.

According to a third aspect of the invention, in the second aspect of the invention, the phase reference position detecting means is the 2-3.
The phase reference position is determined based on the pull-down phase reference position signal and the selection operation. The phase reference position detected by the 2-3 pull-down phase reference position signal is the actual phase reference position of the interlaced video signal. If there is a deviation, the phase reference position designated by the user's selection operation can be settled.

According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the control means records on the recording / reproducing medium based on the detected phase reference position and the detected reproducing speed. The reading position control circuit for controlling the reading position of the reading means for reading the interlaced video signal is provided, and the reading position of the reading means is controlled based on the detected phase reference position and the reproduction speed to obtain the interlaced video. The number of redundant fields in the signal can be made uniform or close to uniform.

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a block diagram showing an overall configuration of a video signal processing apparatus according to an embodiment of the present invention.

The video signal processing apparatus according to this embodiment uses the above-mentioned 2-3 for the recording / reproducing medium 1 such as a magnetic tape.
The recording side for recording the pull-down interlace signal and the reproducing side for variable-speed reproduction of the 2-3 pull-down interlace signal recorded on the recording / reproducing medium 1.

On the recording side, recording on the recording / reproducing medium 1 is performed 2
A 2-3 pulldown phase detection circuit 13 for detecting the 2-3 pulldown phase of the -3 pulldown interlaced signal,
A 2-3 pulldown phase reference generation circuit 12 for generating a 2-3 pulldown phase reference position signal described later based on the detected 2-3 pulldown phase is provided. Simultaneously with the recording of the -3 pulldown interlaced signal, the 2-3 pulldown phase reference position signal is recorded via the control head.

On the reproducing side, a buffer memory 5 for writing / reading a 2-3 pulldown interlaced signal reproduced from the recording / reproducing medium 1, a reproducing speed detecting circuit 2 for detecting a reproducing speed of the recording / reproducing medium 1, A 2-3 pulldown reference position detection circuit 3 for detecting the 2-3 pulldown phase reference position of the 2-3 pulldown interlaced signal based on the 2-3 pulldown phase reference position signal reproduced from the recording / reproduction medium 1, and both. An AT (auto-tracking) control circuit 15 that controls a signal read position from the recording / reproducing medium 1 based on the detection information of the detection circuits 2 and 3, and a synchronization that generates a reference synchronization signal according to a signal format required for output. The circuit 6 and the reproduction speed information from the reproduction speed detection circuit 2 and the 2 from the 2-3 pulldown reference position detection circuit 3
A memory control circuit 4 for generating a control signal for writing / reading or the like to be supplied to the buffer memory 5 based on the 3 pulldown phase reference position information and varying the number of redundant fields of the video signal as described later is provided. .

FIG. 2 is a block diagram for explaining recording of the 2-3 pull-down phase reference position signal on the recording side, and parts corresponding to those in FIG. 1 are designated by the same reference numerals.

The 2-3 pull-down phase detection circuit 13 has 2
The detection of the 2-3 pulldown phase of the -3 pulldown interlaced signal is detected based on the time code value and the correlation between the video signals, that is, the difference between the fields, as in the conventional case.

2-3 pulldown phase reference generation circuit 12
3 based on the detected 2-3 pulldown phase.
The 2-3 pulldown phase reference position signal shown in FIG. This 2-3 pulldown phase reference position signal is shown in FIG.
At the timing of the start of 4 frames and 10 fields of the 2-3 pulldown interlaced signal shown in FIG.
As shown in (b), it is, for example, a signal having a falling 10-field cycle.

That is, as shown in FIG. 9 described above,
For interlaced TV video signals, odd field /
Since there is an even field, a progressive signal, which is an image signal of 24 frames such as movie film, and 2-3
The period that matches the pull-down interlaced signal is 24
4 frames in progressive signal of frame, 2-3
There are 10 fields in the pull-down interlaced signal. The 2-3 pulldown phase reference position signal is a signal whose phase reference position is the position where this cycle starts.

The 2-3 pulldown phase reference position signal is recorded on the magnetic tape 8 as the recording / reproducing medium 1 by the control head 10 shown in FIG.
The 2-3 pulldown interlaced signal is sent to the rotary head 11.
It is recorded on the magnetic tape 8 by. At this time, 2-3
The phase reference positions of the pull-down phase reference position signal and the 2-3 pull-down interlaced signal are recorded as the same phase.
In addition, 9 is a tape drive capstan roller.

The 2-3 pulldown phase reference position signal is not limited to the above-mentioned form as long as the 2-3 pulldown phase reference position signal can be discriminated.
It may be a pulse or the like that matches the phase reference position of 3 pulldown.

FIG. 4 is a block diagram for explaining the detection of the reproduction speed on the reproduction side and the detection of the phase reference position by the 2-3 pulldown phase reference position signal.
The same reference numerals are attached to the portions corresponding to.

The detection of the reproduction speed of the 2-3 pull-down interlaced signal reproduced and output from the magnetic tape 8 as the recording / reproducing medium 1 through the rotary head 11 is performed by detecting the magnetic tape 8
This is done by calculating the speed from the number of rotations of the tape drive capstan roller 9 that is in direct contact with and is rotating. This method is also applicable to other recording / reproducing media other than the magnetic tape, and is a method of reading the change itself of the moving medium and converting it to the actual reproducing speed.

As another method for detecting the reproduction speed of the 2-3 pulldown interlaced signal reproduced and output from the recording / reproducing medium 1, the recording / reproducing medium 1 is recorded at regular intervals during recording of the 2-3 pulldown interlaced signal. Alternatively, the control signal may be recorded by the control head 10, and at the time of reproduction, the reproduction output cycle of the control signal recorded at the above-described constant time may be detected to detect the reproduction speed.

Further, as another method for detecting the reproduction speed of the recording / reproducing medium 1, as shown in FIG. 1, the reproduction speed detecting circuit 2 uses the speed information in the menu based on the instruction from the user as the speed setting command 7. Alternatively, the reproduction speed may be determined by receiving.

Next, the 2-3 pulldown phase reference position during reproduction is detected by the 2-3 pulldown reference position detection circuit 3 by applying the 2-3 pulldown phase reference position signal recorded on the tape 8 to the control head 10. Done by reading through.

Here, the 2-3 pulldown phase on the recording side is detected by detecting the difference between fields. For example, in the case of a signal having no difference such as a still image, 2-3 pulldown phase is detected. The pull-down phase may be erroneously detected. Therefore, in this embodiment, when the 2-3 pulldown phase reference position signal recorded on the magnetic tape 8 and the actual 2-3 pulldown phase of the 2-3 pulldown interlaced signal are deviated, the user While watching the playback screen
By designating any of the five types of selection commands shown in (b) to (f), one of the five types of 2-3 pulldown phase reference position signals with different phase reference positions
2-3 It is regenerated by the pull-down reference position detection circuit 3 and
The 3 pulldown phase reference position can be determined.

Although the cycle of the 2-3 pulldown phase reference position signal is the same as that of 10 fields of the 2-3 pulldown interlace signal, when the variable speed reproduction is performed, the reproduction speed is changed by the change amount. Accordingly, the time interval changes.

Next, the operation when the recording / reproducing medium 1 is reproduced at a variable speed will be described.

In this embodiment, when the recording / reproducing medium 1 on which the 2-3 pulldown interlaced signal is recorded is played back at a variable speed, the visual jerky generated by the collapse of the 2-3 pulldown sequence as described above. In order to reduce the feeling, the writing / reading control of the 2-3 pull-down interlace signal to the buffer memory 5 or the AT control by the AT control circuit 15 is performed so that the number of redundant fields becomes substantially uniform, that is, It is controlled to make it uniform.

First, 0.5 × speed reproduction will be described with reference to FIG.

In FIG. 6A, 2 of 1 × speed reproduction (normal reproduction) is shown.
-3 pull-down interlaced signal, 0.5 in FIG.
A 2-3 pull-down interlace signal obtained from the rotary head 11 in the double speed reproduction, the figure (c) is a signal written in the buffer memory 5 by the write control of the memory control circuit 4, and the figure (d) is a memory control circuit. The output signals read from the buffer memory 5 under the read control of No. 4 are shown.

The reproduction speed detection circuit 2 detects the reproduction speed as described above, and the 2-3 pulldown phase reference position signal reproduced by the 2-3 pulldown reference position detection circuit 3 is used for the 2-3 pulldown phase reference. The position is detected.
The memory control circuit 4 controls writing / reading of the 2-3 pull-down interlaced signal to / from the buffer memory 5 in accordance with the phase of the synchronization reference signal of the synchronization circuit 6 based on the detection information of both detection circuits 2 and 3.

That is, in the 0.5 × speed reproduction, it is known in advance where the redundant field occurs with respect to the 2-3 pulldown phase reference position, and therefore the reproduction speed information and the 2-3 pulldown phase reference position information. Based on the above, the memory control circuit 4 controls writing / reading to / from the buffer memory 5 so as to replace the non-uniform redundant field.

In the 0.5 × speed reproduction, as shown in FIG. 6 (b), 5 from the 2-3 pulldown phase reference position.
The coma changes in the field field. For example, the first 4 fields are coma A and the following 6 fields are coma B. The image changes every 4/60 seconds or 6/60 seconds, and the image is visually jerky. Has become. Therefore, by replacing the frame B in the fifth field with the frame A, the images of the frames A and B become 5 fields at a time and change constantly every 5/60 seconds.

Since the memory control circuit 4 is for 0.5 × speed reproduction, the 2-3 pulldown interlaced signal in the fifth field from the 2-3 pulldown phase reference position is shown in FIG.
As shown in (c), the signal of the field two fields before the buffer memory 5 is read from the buffer memory 5 and is used as an output signal without being written in the buffer memory 5.

As a result, the output signal read from the buffer memory 5 becomes 5 as shown in FIG. 6 (d).
It becomes an image in which the frame changes every 60 seconds, and the jerkiness is reduced.

Next, 1.25 × speed reproduction will be described.

In this embodiment, the AT control circuit 15 controls the read position of the rotary head 11 on the basis of the reproduction speed detection circuit 2 and the 2-3 pull-down reference position detection circuit 3, and FIG. Read out so that the 2-3 pull-down interlaced signal shown in
A video signal whose frame changes every 2/60 seconds is output. As a result, the image does not change every 1/60 seconds or 3/60 seconds as shown in FIG. 10D, and the viewer does not feel discomfort.

Here, 0.5 × speed reproduction and 1.25
Although the double-speed reproduction has been described, other double-speed reproduction is basically the same, and by controlling writing / reading to / from the buffer memory 5 based on the reproduction speed and the 2-3 pull-down phase reference position, or
By controlling the read position by the rotary head 11 by the AT control circuit 15, the number of redundant fields can be made substantially the same, and thereby the visual jerky feeling can be reduced. Therefore, the contents of control for each reproduction speed are prepared in advance as a table.

Next, the recording / reproducing medium 1 was reproduced at a variable speed.
-3 Pulldown interlaced signal to inverse 2-3
The operation of generating the pull-down signal will be described with reference to FIG.

FIG. 7A shows a case of 2 times the 1 × speed reproduction (normal reproduction).
-3 pull-down interlaced signal, 0.5 in FIG.
A 2-3 pull-down interlace signal obtained from the rotary head 11 in the double speed reproduction, the figure (c) is a signal written in the buffer memory 5 by the write control of the memory control circuit 4, and the figure (d) is a memory control circuit. The output signals read from the buffer memory 5 under the read control of No. 4 are shown.

When the output signal format is a television video signal of 24 frames / second, the synchronizing circuit 6 outputs 60 fields / second.
A signal that is synchronized with the second television image signal and the 24th frame / second television image signal is generated, and writing / reading control of the buffer memory 5 is performed based on this synchronizing signal and the 2-3 pulldown phase reference position information. Inverse 2-3 pulldown signals can be obtained even during variable speed reproduction.

(Other Embodiments) Although the 2-3 pulldown phase reference position signal is recorded on the recording / reproducing medium 1 in the above-mentioned embodiment, as another embodiment of the present invention, 2-3 pulldown phase reference position signal is recorded. A plurality of candidates for the 2-3 pulldown phase reference position signal are created on the reproducing side without recording the phase reference position signal, and based on this, the user is allowed to determine the 2-3 pulldown phase reference position signal by a command. May be.

It is needless to say that the control of writing / reading the 2-3 pulldown interlaced signal to / from the buffer memory 5 at the time of variable speed reproduction is not limited to the above embodiment.

[0058]

As described above, according to the present invention, when a recording / reproducing medium in which a 2-3 pulldown interlaced signal is recorded is played back at a variable speed, a visual jerky phenomenon occurs due to a collapse of the 2-3 pulldown sequence. The feeling can be reduced.

Further, even when the medium on which the 2-3 pulldown interlaced signal is recorded is played back at a variable speed, the inverse 2-3 pulldown signal can be generated from the signal in which the 2-3 pulldown sequence is broken.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of 2-3 pulldown phase reference position signal generation according to the embodiment of the present invention.

FIG. 3 is a diagram showing an example of a 2-3 pulldown phase reference position signal according to the embodiment of the present invention.

FIG. 4 is a reproduction speed detection and 2-3 according to the embodiment of the present invention.
It is a figure which shows the structure which detects a pull-down phase reference position.

FIG. 5 is a diagram illustrating a method of determining a 2-3 pulldown phase reference position according to the embodiment of this invention.

FIG. 6 is a diagram for explaining a memory control operation according to the embodiment of the present invention.

FIG. 7 is a diagram for explaining an AT control operation according to the embodiment of the present invention.

FIG. 8 is a diagram for explaining an operation of performing inverse 2-3 pulldown conversion of a reproduction signal by memory control according to the embodiment of the present invention.

FIG. 9 is a diagram for explaining a 2-3 pulldown conversion method.

FIG. 10 is a diagram for explaining a reproduction signal when an interlaced 2-3 pulldown signal is reproduced at a variable speed by a conventional technique.

FIG. 11 is a diagram for explaining inverse 2-3 pulldown conversion.

[Explanation of symbols]

1 recording / reproducing medium 2 reproducing speed detecting circuit 3 2-3 pulldown reference position detecting circuit 4 memory control circuit 5 buffer memory 6 synchronizing circuit 9 tape drive capstan roller 10 control signal recording / reproducing head 11 rotary head 12 2-3 pulldown phase reference Position signal generation circuit 13 2-3 pull-down phase detection circuit 15 AT control circuit

Claims (4)

[Claims] 1. The first frame of a film of 24 frames / second image is divided into two fields, and the second frame is divided into three fields,
Video signal processing to output interlaced video signals by variable-speed playback of a recording / playback medium that records an interlaced video signal converted by the 2-3 pulldown method that converts 60 fields into 24 fields by repeating 5 fields per film 2 frames An apparatus, comprising: phase reference position detecting means for detecting a reference position of 2-3 pulldown phase of an interlaced video signal reproduced from the recording / reproducing medium; and output based on the detected phase reference position and reproduction speed. And a control means for controlling the number of redundant fields of the interlaced video signal to be equalized. 2. The phase reference position detecting means is recorded on the recording / reproducing medium and reproduced from the recording / reproducing medium.
3. A phase reference position is detected based on a −3 pulldown phase reference position signal, and the control means includes a memory control circuit for controlling writing / reading of a reproduced interlaced video signal to / from a memory. 1. The video signal processing device according to 1. 3. The phase reference position detecting means includes the 2-
The video signal processing device according to claim 2, wherein the phase reference position is determined based on the 3 pulldown phase reference position signal and the selection operation. 4. The read position control circuit for controlling the read position of the read unit for reading the interlaced video signal recorded on the recording / reproducing medium, based on the detected phase reference position and reproduction speed. The video signal processing device according to claim 1, further comprising: