JP3301592B2 - Screen size adjustment 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 screen size adjustment device suitable for use in a television receiver having a 6: 9 video display unit (such as a cathode ray tube) and an aspect conversion circuit. The present invention relates to a screen size adjusting device capable of automatically determining whether or not the image is a landscape image in which the image is masked, and displaying the image in an optimal state on a video display unit without a viewer performing a complicated operation.

[0002]

2. Description of the Related Art As shown in FIG.
In FIG. 3, a horizontally long image whose upper and lower parts are masked is converted into a television receiver (hereinafter, wide T) having a wide aspect video display section having an aspect ratio of 16: 9 as shown in FIG.
When displaying the image according to V), it is common to enlarge and display the image using an aspect conversion circuit. In this case, as shown in FIG. 11, the video start position and the video end position of the horizontal image in which the upper and lower portions are masked are detected, and the video is enlarged or moved by the aspect conversion circuit based on these detection results. As a related art related thereto, there is a prior application filed by the present applicant, Japanese Patent Application No. 7-21342 (Japanese Patent Application Laid-Open No. 8-195919), and the like.

As shown in FIG. 12, additional information such as time 11 and subtitles 12 may be superimposed on the upper and lower portions of a horizontally long image in which the upper and lower portions are masked. In addition, an error may occur in the detection of the video end position. According to the above-mentioned prior application, even if there is such additional information, the aspect of the horizontally long image can be accurately detected, and the image is displayed on the video display section of the wide TV as shown in FIG.

[0004]

By the way, the number of channels (the number of broadcasting stations) has increased due to the spread of digital broadcasting, and as a result, as shown in FIGS. The information 13 is often added to the right or left end of the upper mask portion. According to the conventional technology, the horizontally long images shown in FIGS.
The image is displayed on the video display section of the wide TV as shown in FIGS.

[0005] However, when there is additional information 13 that is not so important, such as a symbol of a broadcasting station, FIG.
As shown in (A) and (B), the number of viewers who do not want to display a slightly smaller image while leaving the upper mask portion increased, and improvement has been desired. The present invention has been made in view of such a problem, and it is possible to display a more powerful image even when additional information is superimposed on an upper mask portion of a horizontal image in which the upper and lower portions are masked. It is an object to provide a screen size adjusting device.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the prior art, the present invention determines the presence or absence and position of upper and lower mask portions in an incoming video signal, and reduces the screen size according to the image. In the screen size adjusting device for adjusting, an image based on the image signal is divided into at least three regions of left, center, and right, and image start position detecting means for detecting an image start position in each region;
An additional information determining unit that determines whether or not additional information is superimposed on a mask portion above one of the left and right regions based on a pattern of a video start position detected in each of the regions; If it is determined that the additional information is superimposed, the video start position of the area determined to have the additional information superimposed is ignored, and the video start position is determined based on the video start positions of other areas. A video start position determining unit, and an aspect conversion unit configured to perform an aspect conversion on the video signal based on the video start position obtained by the video start position determining unit. The first image start position where the image start position and the image start position of one of the left and right areas are substantially the same, and the image start position of the other area on the left or right When detecting a pattern that is a second video start position different from the first video start position and the second video start position is above the first video start position, an upper mask It is an object of the present invention to provide a screen size adjusting device characterized in that it is determined that additional information is superimposed on a portion.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A screen size adjusting device according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram showing an embodiment of a screen size adjusting device of the present invention,
2 to 8 are diagrams for explaining the operation of the screen size adjusting device of the present invention.

In FIG. 1, an incoming video signal is supplied to a low-pass filter 1, a sync separation circuit 3, and an aspect conversion circuit 6.
Is input to The low-pass filter 1 removes high-frequency components of the input video signal and inputs the same to the A / D conversion circuit 2.
This is because the high frequency component is unnecessary for detecting the mask portion since the frequency constituting the mask portion in the image is a low frequency component, and if the low frequency component of 0 to 800 kHz is sampled in the video signal, Because it is enough. When the S / N ratio of the video signal is low, the low-pass filter 1 removes random noise and pulse-like noise due to sparks to prevent erroneous detection. The latter A / D conversion circuit 2 also plays a role of using a low-cost A / D conversion circuit with a low sampling frequency. Since the required frequency component is low, even if the incoming video signal is a composite signal, the color component superimposed at 3.58 MHz in NTSC cannot pass, and only the luminance component simply passes. Therefore, an incoming video signal operates in the same manner whether it is a luminance signal after Y / C separation or a composite signal.

On the other hand, the synchronization separation circuit 3 separates a synchronization signal from the input video signal and supplies a timing generation circuit 4 with video timing signals such as a horizontal synchronization signal and a vertical synchronization signal. The horizontal synchronizing signal is necessary for counting the number of lines, and the vertical synchronizing signal is necessary for detecting the start position of the video. The timing generation circuit 4 supplies a capture timing signal for capturing video data to the arithmetic circuit 5. The arithmetic circuit 5 captures the video data converted into a digital signal by the A / D conversion circuit 2 based on the capture timing signal, analyzes the video data by a method described in detail later, and determines whether the incoming video signal is up or down. It is determined whether or not the image is a landscape image in which a portion is masked. Note that a microcomputer can be used as the arithmetic circuit 5, and in this case, there is no problem even if the A / D conversion circuit 2 has a built-in microcomputer. Further, here, the arithmetic circuit 5 using the timing generation circuit 4 is used.
The timing generation circuit 4 is not always necessary when the same capture control can be performed by the horizontal synchronization signal and the vertical synchronization signal inside the arithmetic circuit 5.

Then, as a result of the analysis of the video data by the arithmetic circuit 5, the incoming video signal is shown in FIG.
If it is determined that the image is a horizontally long image having an aspect ratio of 4: 3 as shown in FIG. 9 but masking the upper and lower parts, the arithmetic circuit 5 instructs the aspect conversion circuit 6 to perform the aspect conversion as shown in FIG. The aspect conversion circuit 6 converts the aspect of the input video signal in accordance with the instruction and supplies it to the CRT 7. Note that the aspect conversion circuit 6
Is a well-known aspect conversion means for converting the aspect of an image by digital signal processing, or converting the aspect of an image by manipulating at least one of horizontal and vertical deflection widths. Therefore, an image whose aspect has been converted into an optimum state for the incoming video signal is displayed on the surface of the cathode ray tube 7.

Here, a method for capturing video data by the arithmetic circuit 5 and an analysis method thereof will be described. As shown in FIG. 2, the arithmetic circuit 5 first operates over a field in the vertical direction of the screen at a predetermined horizontal position (for example, the left end in the figure) according to the capture timing specified by the timing generation circuit 4. Import video data. In the next field, the horizontal position is delayed backward, the video data is similarly captured at the second horizontal position, and the final horizontal position (for example,
When the image is taken up to the right end in the figure), it returns to the horizontal top position. As described above, if the operation of capturing the video data is continuously performed until the sampling in the horizontal direction of the screen is completed, the data of the entire screen is obtained. The number of divisions in the horizontal direction may be arbitrary, and the division width may be narrower or wider than in FIG. If the capacity of the arithmetic circuit 5 is high and the memory is abundant, the entire screen may be sampled simultaneously.

The arithmetic circuit 5 is provided at the upper end D in FIG.
And the average value μ0 of the luminance in the range of the lower end E. If the average value μ0 of the luminance is a value larger than a certain value, it can be determined that the input video signal is not a horizontal image in which the upper and lower portions are masked. Can be determined to be a landscape image in which is masked. If the arithmetic circuit 5 determines that the image is a horizontally long image in which the upper and lower portions are masked, the arithmetic circuit 5 sets a value obtained by adding a noise margin to the average value μ0 as a reference value μ1 corresponding to the luminance value of the mask portion. The arithmetic circuit 5 binarizes the video data from the A / D conversion circuit 2 (converts the image data into 0 and 1) using the reference value μ1 as a threshold value. As described above, each sampled data is converted into a value of either 0 or 1.

In the screen size adjusting device having such a configuration, as shown in FIG.
It is necessary to detect the additional information start position and the video start position. Thus, as an example, as shown in FIG. 4, the arithmetic circuit 5 moves the screen in the horizontal direction (left, center, right) to A, B, C
Then, the presence or absence of the additional information 13 and the start position of the additional information are obtained. The number of screen divisions is not limited to this, and may be any number as long as it is at least three.

In FIG. 4, it is assumed that each of the areas A, B, and C contains m pieces of sampling data. The arithmetic circuit 5 integrates the binarized data in the horizontal direction in each of the areas A, B, and C. Then, in each of the areas A to C, as a result of integration, a histogram φ as shown in FIGS. 5A, 5B, and 5C is obtained.
A, φB, and φC can be obtained. FIG.
(C) corresponds to the areas A to C, respectively.

The arithmetic circuit 5 has a histogram φ shown in FIG.
The video start position (including the additional information start position of the additional information 13) can be detected by A to φC. Assuming that the vertical position (line number) is θ, the value of θ is small at the top of the screen and large at the bottom,
In each of the histograms φA to φC, the point at which data first rises when viewed from the top of the screen is the video start position or the additional information start position of the additional information 13. FIG.
Alternatively, as shown in FIG. 6, in areas A to C, the positions where data first rises are represented by θA, θB, and θ, respectively.
C. In this example, the video start positions θA, θB, θC
Of these, the positions θA and θB are actual video start positions, and the position θC is the additional information start position of the additional information 13. Although not shown here, the histograms φA to φA
With C, the video end position is similarly obtained.

The additional information 13 shown in FIG. 3, FIG. 4 or FIG.
14A, when the additional information 13 exists at the left end of the upper mask portion, as shown in FIG. 14B, when the additional information 13 exists at the right end of the upper mask portion. In (), θA, θB, and θC have the following relationship. θA = θB and θC <θA: The image start position is θA, θ
B, the additional information start position of the additional information 13 is θC θC = θB and θA <θC...
C, the additional information start position of the additional information 13 is θA

As described above, the arithmetic circuit 5 includes the areas A to C
The presence or absence of the additional information 13 and the actual video start position can be detected based on the patterns of the video start positions θA to θC obtained in the above. Then, when the additional information 13 exists,
As shown in FIG. 7, the arithmetic circuit 5 regards the image as an image equivalent to a landscape image in which the additional information 13 does not exist. As shown in FIG. (Video display section)
It controls the aspect conversion circuit 6. As a result, even when the additional information 13 that does not need to be displayed on the video display unit exists, the video can be further enlarged and displayed without leaving the upper mask portion. It can be used to display more powerful images.

It is to be noted that subtitles may be superimposed on the lower mask portion. Therefore, if additional information superimposed on the lower mask portion is detected, the additional information is not ignored. The arithmetic circuit 5 controls the aspect conversion circuit 6 to display the additional information superimposed on the lower mask portion.
Control.

The present invention is not limited to the configuration shown in FIG. 1, and the method of capturing video data is not limited to FIG. The specific configuration may be arbitrary as long as the video based on the input video signal is divided into at least three regions of left, center, and right, and a video start position detecting unit that detects a video start position in each region is provided.

[0020]

As described in detail above, the screen size adjusting apparatus according to the present invention can display an image based on an image signal on the left, center,
Image start position detection means for dividing the image into at least three regions on the right and detecting the image start position in each region, and detecting the image start position in each region from the pattern of the image start position detected in each region. Additional information determining means for determining whether additional information is superimposed on the mask portion, and when the additional information determining means determines that the additional information is superimposed, it is determined that the additional information is superimposed. Ignores the video start position of the
A video start position determining unit that determines a video start position based on a video start position in another area; and an aspect conversion unit that performs aspect conversion on a video signal based on the video start position obtained by the video start position determination unit. The additional information determination means is configured such that the video start position of the central region and the video start position of one of the left and right regions are substantially the same as the first video start position, and the left or right of the other region is the same. When detecting a pattern in which the video start position is a second video start position different from the first video start position and the second video start position is above the first video start position, Since it is determined that the additional information is superimposed on the mask portion, even when the additional information is superimposed on the upper mask portion of the horizontal image in which the upper and lower portions are masked, a more powerful image is displayed. It can be.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a diagram for explaining the operation of the present invention.

FIG. 3 is a diagram for explaining the operation of the present invention.

FIG. 4 is a diagram for explaining the operation of the present invention.

FIG. 5 is a diagram for explaining the operation of the present invention.

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

FIG. 7 is a diagram for explaining the operation of the present invention.

FIG. 8 is a diagram for explaining the operation of the present invention.

FIG. 9 is a diagram showing a landscape image in which upper and lower portions are masked.

FIG. 10 is a diagram showing a wide aspect video display unit.

FIG. 11 is a diagram illustrating a video start position and a video end position of a landscape image in which upper and lower portions are masked.

FIG. 12 is a diagram illustrating a landscape image in which upper and lower portions are masked and additional information is superimposed on the mask portion.

FIG. 13 is a diagram showing aspect conversion according to a conventional example.

FIG. 14 is a diagram illustrating a landscape image in which upper and lower portions are masked and additional information is superimposed on the mask portion.

FIG. 15 is a diagram showing aspect conversion according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Low-pass filter 2 A / D conversion circuit 3 Synchronization separation circuit 4 Timing generation circuit 5 Operation circuit 6 Aspect conversion circuit 7 CRT

Claims (1)

(57) [Claims] 1. A screen size adjusting device for determining the presence or absence and position of upper and lower mask portions in an incoming video signal and adjusting the screen size in accordance with the image, comprising: At least 3
While dividing into two regions, the image start position detecting means for detecting the image start position in each region, from the pattern of the image start position detected in each of the regions, to the upper mask part of the left or right region Additional information determining means for determining whether or not the additional information is superimposed; and an area in which the additional information is determined to be superimposed when the additional information determining means determines that the additional information is superimposed. A video start position deciding means for ignoring the video start position of the other region and determining a video start position based on a video start position of another area, and the video signal based on a video start position obtained by the video start position determining means. An aspect conversion unit for performing an aspect conversion, wherein the additional information determination unit is configured to determine whether the video start position of the central region is one of a left and right position. Is the first video start position that is substantially the same as the video start position of the area, and the video start position of the other area on the left or right is the second video start position that is different from the first video start position. And detecting, when detecting a pattern in which the second video start position is above the first video start position, additional information superimposed on an upper mask portion. Size adjustment device.