JPH05207414A - Video signal processing circuit - Google Patents

Abstract

PURPOSE:To observe a video at a best segmentation position at all times even when a part desired to be observed is changed timewise by storing the recording position of the video and the segmentation position of a picture at 1st reproduction and referencing to the content of a memory at 2nd and succeeding reproduction so as to set automatically the segmentation position. CONSTITUTION:A conversion position setting means 100 decides which part of a 16:9 wide picture recorded on a recording medium is to be magnified to 4:3, and a time base conversion means 200 magnifies the picture designated by the conversion position setting means 100 in the horizontal direction and converts the aspect ratio into the prescribed ratio (4:3). A recording position detecting means 16 detects in which part of the recording medium the reproduced picture is recorded. A storage means 3 stores an identification signal at a position obtained by the recording position detecting means 16 and the conversion position set by the conversion position setting means 100 and applies aspect conversion in an optimum field angle automatically based on data from the storage means 3 at the time of the reproduction.

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 circuit for displaying a wide aspect video signal on a conventional receiver having an aspect ratio of 4: 3.

[0002]

2. Description of the Related Art At present, a wide aspect aspect of a television receiver is being studied as an EDTV system. This is to change the conventional receiver having an aspect ratio of 4: 3 to the aspect ratio of 16: 9 to enhance the realistic sensation of a large-screen receiver. FIG. 7 shows how the screen looks depending on the aspect ratio. FIG. 7 (a) shows a scene displayed on a conventional 4: 3 receiver, and FIG. 7 (b) shows 1
It is displayed on a receiver having an aspect ratio of 6: 9. In such a wide aspect image receiver, a wider range of images can be displayed.

By the way, a standardized wide aspect signal source and a receiver are required to view a wide aspect image. EDTVII broadcasting, a wide-aspect movie, etc., which are currently under study, can be considered as a signal source. Especially for a wide-aspect movie, it is easy to put into practical use because it is rarely confined to the conventional broadcasting system, and it is likely that it will spread rapidly. is there. With regard to image receivers, it is expected that more users will buy new 16: 9 wide image receivers as the software spreads. However, it takes a considerably long time to completely switch from the conventional 4: 3 receiver to the wide receiver. In addition, the following inconveniences are likely to occur during the transition period when the two methods coexist. That is, this is the case where the user has a wide movie but does not have a wide receiver. Movie 16:
Even if it is possible to switch between 9 and 4: 3, there is a possibility that the user will shoot in the 16: 9 mode on the assumption that a wide image receiver will be purchased in the future. In such a case, a conventional 4: 3 image receiver produces a vertically long image as shown in FIG. 8A, which is far from the original image. Further, as shown in FIG. 8B, even if the aspect ratio is corrected, the display range is narrowed, so that the portion to be viewed goes out of the screen.

[0004]

As described above,
If you have a signal source such as a wide movie in the transition period from a 4: 3 aspect ratio to a wide aspect ratio of 16: 9 but only a receiver with an aspect ratio of 4: 3, the image displayed on the receiver is There was a drawback that it became vertically long and was far from the original image. Further, even if the aspect ratio is converted to 4: 3, the display range of the screen is narrowed, so that both ends of the screen cannot be seen and the desired portion cannot be seen.

The present invention has been made to solve the above-mentioned problems, and it is possible to display a wide image of 16: 9 on a 4: 3 receiver with a correct aspect ratio, and at the By setting the area you want to see, even if the set part moves, it is possible to automatically select and display the cutout position so that the set area of the 16: 9 image is almost in the center, and it is also recorded. In the case of a wide source reproduced from a medium, it is an object to obtain a video signal processing circuit capable of automatically displaying an optimum angle of view during reproduction by storing a scene and a horizontal position in association with each other.

[0006]

A video signal processing circuit according to a first aspect of the present invention is a conversion position for designating an arbitrary horizontal position of an input video signal using a wide signal recorded on a recording medium as an input. The setting means, the time axis conversion means for enlarging the image portion set by the conversion position setting means to have a predetermined aspect ratio, the recording position detecting means for indicating the recording position of the image, and the recording position detecting means. And a storage unit for storing the set value of the conversion position setting unit with respect to the obtained image position.

A video signal processing circuit according to a second aspect of the present invention is set by a region setting means and a region setting means for setting a region at an arbitrary position on a screen by inputting a video signal having an aspect ratio of 16: 9. Set by the conversion position setting means for receiving an output signal of the motion detection means and designating an arbitrary horizontal position of the input video signal And a time axis conversion means for enlarging the image portion so as to have a predetermined aspect ratio.

[0008]

The conversion position setting means of claim 1 according to the present invention is
It is determined which part of the 16: 9 wide image recorded on the recording medium is to be expanded to 4: 3, and the time axis conversion means horizontally expands the image of the part designated by the conversion position setting means. Then, the aspect ratio is converted to a predetermined (4: 3) aspect ratio. The recording position detecting means detects in which part of the recording medium the reproduced image is recorded, and the storing means sets the position identification signal obtained by the recording position detecting means and the conversion position setting means. Remember the conversion position and
At the time of reproduction, the aspect conversion is automatically performed at the optimum angle of view by the data from the storage means.

According to a second aspect of the present invention, the area setting means specifies one area of the divided input screen, the motion detecting means detects a horizontal movement of the specified area, and the conversion position setting means , Determining which part of the 16: 9 wide image is to be enlarged to 4: 3 in accordance with the horizontal movement of the specified region, and the time axis conversion means is the part specified by the conversion position setting means. Image is enlarged in the horizontal direction and converted into a predetermined (4: 3) aspect ratio.

[0010]

EXAMPLES Example 1. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of the present embodiment and shows a case where it is applied to a video tape recorder. When converting a wide image with an aspect ratio of 16: 9 into an aspect ratio of 4: 3, it is conceivable that the best cutout portion changes with time. For example, when a movie or the like is shot and then played back, the part to be viewed was from the left end to the center part, but with time, it may change to move to the right side and look at the right end from the center. In such cases, 1
By storing the screen and the cut-out position in association with each other in the second reproduction, it is possible to automatically control the cut-out position in the second and subsequent reproductions. In FIG. 1, 1
Is an input terminal to which a video signal having an aspect ratio of 16: 9 is input. Reference numeral 2 converts the video signal input by the A / D converter from an analog signal to a digital signal. A memory circuit 3 temporarily stores the digitized video signal. Reference numeral 4 denotes a sync separation circuit that separates the sync signal from the input video signal. A write clock generator 5 generates a clock necessary for writing to the memory circuit 3. A write address counter 6 generates a write address of the memory circuit 3. Reference numeral 7 is a preset circuit which determines the position where the counter of the write address counter is reset to address 0. A write address reset pulse generation circuit 8 generates a reset pulse according to a preset circuit output signal. Reference numeral 9 is a read-out clock generating circuit, which generates a clock necessary for reading the video data from the memory circuit 3. A read address counter 10 generates a data read address. Reference numeral 11 denotes a sync signal generation circuit, which receives the output signal of the read clock generation circuit as an input and generates a composite sync signal and a reset signal of the read address counter. A sync signal adding circuit 12 adds a sync signal to the video data output from the memory circuit 3. A D / A converter 13 converts a digital video signal into an analog signal. A terminal 15 receives a CTL signal.
Reference numeral 16 is a recording position detection circuit that associates the tape position with the image content. A recording position storage circuit 17 stores the tape position and aspect conversion range data in pairs. A switch circuit 18 controls writing to the recording position storage circuit.

FIG. 2 is an image diagram for explaining the basic operation of the present invention. FIG. 2 (a) shows the central part of a 16: 9 input video signal which is aspect-converted to 4: 3. FIG. 6B shows a state in which the left part of the 16: 9 input video signal is aspect-converted to 4: 3.
3A and 3B are waveform diagrams of input / output signals of respective parts in the writing process to the memory. FIG. 3A is a 16: 9 video signal input waveform, FIG. 3B is a horizontal synchronizing signal, and FIG. Is a write clock, (d) is a preset signal waveform, and (e) is an address generation circuit output waveform. FIG. 4 is a waveform diagram of input / output signals of each part in the memory reading process. FIG. 4A is a reading clock waveform, FIG. 4B is a reading address counter reset pulse output waveform, and FIG. Readout address generator output signal waveform, 16: 9 input video signal waveform in the same figure (d), 4: 4 in the same figure (e).
3 is an output signal waveform whose aspect is converted to 3.

Next, the operation will be described. First,
The writing process to the memory during the first reproduction will be described. As shown in FIG. 3A, a video signal having an aspect ratio of 16: 9 is input to the terminal 1 and supplied to the A / D converter 2 and the sync separation circuit 4. A / D converter 2
The analog video signal input to is supplied to the memory circuit 3 after being digitized. The memory circuit 3 is generally composed of semiconductor elements such as DRAM or SRAM. The sync separation circuit 4 extracts the horizontal sync signal shown in FIG. 3B from the video signal. The separated horizontal synchronizing signal is supplied to the write clock generating circuit 5 and is multiplied up to a frequency of about 19 MHZ. The write clock frequency fW is determined by the aspect conversion ratio, and the read clock frequency fR described later is about 14.318 MHz (910f
h. ． If fh is a horizontal frequency of 15.734 KHz), it is represented by the following equation. FIG. 3C shows the write clock waveform with the time axis enlarged. fW = (16/3/4) * fR = 1.33 * 14.318MHz≈19MHz (1210fh)

Next, the output signal of the write clock generation circuit 5 is supplied to the write address counter 6 to generate an address necessary for writing to the memory circuit 3.
When the entire 1H period (1H is 1 horizontal cycle) of the video signal is taken into the memory, the address 1210 is required.
Since it is not necessary to store the blanking portion including the horizontal synchronization portion, it is assumed here that 720 samples are written in the memory.

On the other hand, CTL (control signal) is inputted from the terminal 15 and inputted to the image position detecting circuit 16.
If the image position detection circuit 16 records data by changing the duty ratio like VASS or time code adopted in the VHS standard, the image recording position can be detected with high accuracy. Next, the output signal of the image position detection circuit 16 is supplied to the recording position storage circuit 17. While viewing the reproduced image, the viewer supplies the recording position storing circuit 17 with the preset circuit 7 at the cut-out position of the screen, that is, the reset position of the write address counter 6 by turning on the SW circuit 18. Recording position storage circuit 17
Stores these two signals (image recording position and cut-out position) in association with each other. Each time the cutting position is changed, it is stored in the recording position storage circuit 17 each time. The output signal of the recording position storage circuit 17 is supplied to the write address reset pulse generation circuit 8 to generate the pulse shown in FIG.
Here, the preset circuit 7 and the write address reset pulse generation circuit 8 constitute the conversion position setting means 100. The output signal of the write address reset pulse generation circuit 8 is supplied to the write address counter 6 to reset the address counter to address 0. In the case of the embodiment, the data written at this address 0 is located at the left end on the screen. The setting of the reset position by the preset circuit 7 can be arbitrarily decided by the user according to the contents of the screen. That is, the reset position may be set to the left when the left portion of the screen is desired to be seen, and the reset position may be set to the right when the right portion of the screen is desired to be seen. FIG. 3E shows a waveform diagram of the output signal of the write address counter 6 when the left part of the screen is viewed. The output signal of the write address counter 6 is supplied to the memory circuit 3 so that the video data becomes 0.
It is written in order from the address. The above is the first write operation to the memory.

Next, the second and subsequent memory writing operations will be described. The CTL signal is input from the terminal 15 and input to the image position detection circuit 16. The output signal of the image position detection circuit 16 is supplied to the recording position storage circuit 17.
As the output signal of the recording position storage circuit 17, a setting signal of the cut-out position designated by the preset circuit 7 at the time of the first reproduction is obtained and supplied to the write address reset pulse generation circuit 8. In this case, the SW position 18 does not connect the recording position storage circuit 17 and the preset 7 circuit.
The subsequent write operation to the memory is the same as the first operation.

Next, the reading operation from the memory circuit will be described. The read clock generation circuit 9 is shown in FIG.
As shown in (a), 14.318 MHz (910 fh)
A clock having a frequency of
It is also supplied to the read address counter 10. The sync signal generation circuit 11 uses a composite sync signal and a later-described FIG.
The reset signal of the read address counter 10 and the like shown in FIG. The read address counter 10 is a counter similar to the write address counter 6, and specifies an address when reading the video data written in the memory circuit 3. The read address counter 10 uses the reset signal that generates a pulse at a fixed position from the horizontal synchronizing signal generated by the synchronizing signal generating circuit 11 as shown in FIG.
The counter is reset to 0 as shown in (c),
This position is the starting point of the video data. Here, the memory circuit 3, the sync separation circuit 4, the write clock generation circuit 5, the write address counter 6, the read clock generation circuit 9, the read address counter 10, and the sync signal generation circuit 11 constitute a time axis conversion circuit 200. ing.

The video data read from the memory circuit 3 has its time axis converted by the difference in the frequencies of the write clock and the read clock, and at the same time as the read, the aspect ratio is changed from 16: 9 to 4: 3. Next, the output signal of the memory circuit 3 is supplied to the synchronization adding circuit 12 to add the composite synchronizing signal, and then the D / A converter 1
3 converts into an analog signal as shown in FIG. In this way, the left portion of the 16: 9 input video signal shown in FIG. 4D is cut out and simultaneously converted into a 4: 3 aspect.

In the above embodiment, the NTSC system was used as an example to set the read clock frequency to 14.318 MHz and the write clock frequency to 19 MHz, but the present invention is not limited to these frequencies. Although the video cutout position is determined by the write address reset position, the same effect can be obtained by the read address reset position.

Further, in the above-described embodiment, the CTL signal is used for detecting the recording position, but the present invention is not limited to this. If the frame number or the like is recorded, this can be used. In the above embodiment, only the luminance signal was explained,
It goes without saying that if the input signal is a color difference signal, the same processing can be performed.

Example 2. Next, an embodiment of the invention of claim 2 will be described with reference to the drawings. FIG. 5 is a block diagram of this embodiment, and shows a case of receiving a television broadcast. In the figure, 20 is an area setting circuit for setting one area on the screen. Reference numeral 21 is a motion detection circuit that detects the amount of horizontal movement of the set area.

Next, the operation will be described. The wide aspect video signal input to the terminal 1 is sent to the A / D converter 2
Is converted into a digital signal by. The output signal of the A / D converter 2 is supplied to the area setting circuit 20. Area setting circuit 20
As shown in FIG. 6A, the viewer sets a region of a portion on the screen that the viewer particularly wants to pay attention to. A mouse or a jog dial can be used as the setting means. Next, the output signal of the area setting circuit 20 is supplied to the motion detection circuit 21. The motion detection circuit 21 detects the horizontal motion of the video signal for which the area is set. As a specific method for detecting the motion, the correlation of the inter-frame difference may be checked. The output signal of the motion detection circuit 21 is supplied to the preset circuit 7 and the output signal of FIG.
As shown in (b), the range to be aspect-converted is set so that the area set according to the movement falls within the screen of the 4: 3 receiver. The output signal of the preset circuit 7 is supplied to the reset pulse generation circuit to generate a reset pulse according to the conversion range. The following operations for writing to and reading from the memory are the same as those in the first embodiment, and therefore will be omitted.

[0022]

As described above, according to the first aspect of the present invention, when the recorded video signal having the aspect ratio of 16: 9 is reproduced, the recording position of the video and the cut of the image are reproduced during the first reproduction. Since the playback position is stored and the playback position is automatically set by referring to the contents of the memory during the second and subsequent playbacks, the best playback position is always set even when the part you want to see changes with time. This has the effect of being able to see the image at the dashi position.

Further, according to the invention of claim 2, when the area to be viewed is set, the area is controlled so as to be within the screen of the 4: 3 receiver. Even in the case of the source, if the viewer sets the desired area, the video can be automatically viewed at the optimum cutting position.

[Brief description of drawings]

FIG. 1 is a block circuit diagram of a video signal processing circuit according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining an image cutout method of the present embodiment.

FIG. 3 is a diagram for explaining a memory writing operation according to the present embodiment.

FIG. 4 is a diagram for explaining a reading operation from a memory according to the present embodiment.

FIG. 5 is a block circuit diagram of a video signal processing circuit according to another embodiment of the present invention.

FIG. 6 is a diagram for explaining the operation of FIG.

FIG. 7 is a diagram showing a difference in appearance between a wide aspect image and a conventional aspect image.

FIG. 8 is a diagram showing a display example by a conventional aspect conversion method and a display example when a wide aspect image is connected to a conventional image receiver.

[Explanation of symbols]

1 Wide Image Input Terminal 2 A / D Converter 3 Memory-Circuit 4 Sync Separation Circuit 5 Write Clock Generation Circuit 6 Write Address Counter 7 Preset Circuit 8 Reset Pulse Generation Circuit 9 Read Clock Generation Circuit 10 Read Address Counter 11 Sync Signal Generation circuit 12 Synchronization addition circuit 13 D / A converter 15 CTL signal input terminal 16 Recording position detection circuit 17 Recording position storage circuit 18 SW circuit 20 Area setting circuit 21 Motion detection circuit 100 Conversion position setting means 200 Time axis conversion means

Claims (2)

[Claims] 1. A video signal processing circuit for displaying a video signal having an aspect ratio of 16: 9 recorded on a recording medium as an input signal on a receiver having an aspect ratio of 4: 3. A conversion position setting means for setting an arbitrary horizontal position of an input video signal having a ratio of 16: 9 and a video signal of a portion determined by the conversion position setting means are 4: 3.
The time axis conversion means for converting the aspect ratio of the video signal, the recording position detection means for indicating the recording position of the video signal, and the recording position storage circuit for storing the set value of the conversion position setting means with respect to the recording position. A video signal processing circuit, characterized in that the output signal of the recording position storage circuit is supplied to the time axis conversion means to automatically set a video cutting position. 2. A video signal processing circuit for displaying a video signal having an aspect ratio of 16: 9 as an input signal on a receiver having an aspect ratio of 4: 3, which is a region setting for designating a region within a screen. Means, a motion detecting means for detecting the motion of the area designated by the area setting means, a conversion position setting means for receiving the output signal of the motion detecting means and setting a position for aspect conversion, and the conversion position setting means. And a time axis conversion means for converting the video signal of the portion determined by the aspect ratio into a 4: 3 aspect ratio, and automatically cuts out the video image so that the designated area falls within the screen with the aspect ratio of 4: 3. A video signal processing circuit, wherein: