JPH09214846A - Video signal processing device - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a video signal processing device that switches to an optimum video size when a caption inside a video is detected and also moves the caption appropriately. A border detection circuit 41 for detecting a border around a subtitle character, a first delay circuit 42 for delaying a border signal detected by the border detection circuit 41, a character detection circuit 43 for detecting a subtitle character, and a character Detection circuit 43
The second delay circuit 44 for delaying the character signal detected by
A first AND circuit 45 that takes the logical product of the signal output from the delay circuit 42 and the character signal, a second AND circuit 46 that takes the logical product of the signal output from the second delay circuit 44 and the trimming signal, and the signal output from the first AND circuit 45 And the second AND circuit 46
The OR circuit 47 takes the logical sum of the signals output from

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wide television receiver having a display screen with a wide aspect ratio, and in particular, it determines the position and size of a subtitle from an input video signal and automatically moves the subtitle. The present invention relates to a video signal processing device that makes it possible.

[0002]

2. Description of the Related Art In recent years, a television receiver having a horizontally wide screen having an aspect ratio of "16: 9" is provided in contrast to a standard television receiver having the standard NTSC system having an aspect ratio of "4: 3". Has appeared.

Commercially available television receivers having a wide-aspect screen include genuine high-definition television receivers, simplified high-definition television receivers, and MUSE-N.
There are 525 wide television receivers that are equipped with a TSC converter and have the same number of scanning lines as the current ones, and wide television receivers that are not equipped with a MUSE-NTSC converter.

Here, the wide television receiver displays an image with the same number of scanning lines (525 lines) as the standard television receiver, and the aspect ratio "4: 4: 4" composed of standard image signals according to the current NTSC system or the like. When displaying the standard image of "3", the image is displayed as a wide image which is horizontally expanded.

By the way, when displaying an image such as a movie called a cinema scope size or a Vista vision size (hereinafter referred to as a cinema image) on a standard television receiver, the original image size is displayed without trimming. In addition, the width of the cinema image is displayed so as to match the width of the standard screen. When displayed in this manner, black bands with no image are displayed as blank areas above and below the standard screen.

On the other hand, when displaying a cinema image on a wide television receiver, the image portion is expanded at the same aspect ratio, and the length of the image in the vertical direction of the wide screen having the wide aspect ratio is set to the vertical direction. By matching the length, it is possible to display the full screen on the wide screen without trimming the original video size.

However, in some cinema videos such as Western movies, Japanese subtitles are displayed in the blank area on the premise of broadcasting or reproduction on a standard television receiver. When such an image is expanded and displayed in full size on the wide screen of the wide television receiver, there is a disadvantage that the subtitle portion is out of the screen and cannot be seen.

Therefore, the video signal of the subtitle portion is delayed,
A technique has been proposed in which the caption is moved into the video by combining with the video signal of the next frame so that the caption can be seen even after the video is expanded (for example, Japanese Patent Laid-Open No. 3-127).
565, etc.). Also, a technique has been proposed in which a video size is detected from an input video signal and automatically switched to an optimum display mode (for example, Japanese Patent Laid-Open No. 1-305786).
Issue publication). By using these techniques, a video signal processing device that automatically switches the video size to an optimum display mode and at the same time moves subtitles has become possible.

FIG. 17 is a block diagram showing an example of this video signal processing apparatus, and the configuration and operation of this video signal processing apparatus will be described below.

The input color video signal is separated by the Y / C separation circuit 101 into a luminance signal and a chroma signal. The separated luminance signal is input to the luminance level comparison circuit 102 and the sync separation circuit 104. Brightness level comparison circuit 102
Outputs a portion of the luminance signal equal to or higher than a predetermined threshold value to the video area detection circuit 103.

On the other hand, the sync separation circuit 104 extracts the horizontal sync signal and the vertical sync signal from the luminance signal and sends them to the gate signal generation circuit 105. In the gate generation circuit 105,
Various gate signals are created based on the vertical sync signal and the horizontal sync signal, and the video area detection circuit 1 is used as a timing signal.
Send to 03.

The image area detection circuit 103 is based on the luminance signal and the timing signal sent from the gate signal generation circuit 105, and the start line b and the end line c of the image.
Is detected and the data is output to the control circuit 106.

The control circuit 106 includes a video area detection circuit 1
The display mode of the video is determined based on the data from 03, and at the same time, the area below the video area is the subtitle area.
A control signal for moving the subtitles to the lower side of the screen is output according to the display mode.

Further, the image size switching circuit 107 switches the image size to be displayed on the display screen based on the decision of the control circuit 106, and the image display circuit 108 decides the center position of the image according to the image size to be displayed. To do. Further, the caption moving circuit 1 is controlled by the control signal of the control circuit 106.
09 controls the display position of subtitles. Subtitle moving circuit 109
Is composed of a moving IC and a memory, and based on a control signal from the control circuit 106, the moving IC writes to and reads from the memory to move the subtitle to a predetermined position and display it.

[0015]

In the above-mentioned video signal processing device, it is assumed that the subtitle exists in the blank portion only. However, in reality, the subtitle is included in the video area as shown in A of FIG. May be present in both blank areas. For example, when an image signal displaying subtitles of ~ in the video area and displaying subtitles of ~ in the blank area is input, in the above-described video signal processing device,
When the subtitles ~ in the blank area are moved to the inside of the video area, the subtitles ~ in the video area overlap the subtitles ~ in the video area, as shown in B of Fig. 18.

In order to avoid such a problem, it may be considered that the caption is not moved when the caption is detected inside the video. However, it is easy to detect the subtitles in the blank area, but when detecting the subtitles in the video, it is difficult to detect the video signal and the subtitle signal separately, and the subtitle movement is automatically and accurately controlled. Was difficult.

In view of the above points, it is an object of the present invention to provide a video signal processing device that switches to an optimum video size when a caption inside a video area is detected and also moves the caption appropriately.

[0018]

DISCLOSURE OF THE INVENTION The present invention is an image in which a cinema image having blank areas at the top and bottom is expanded to display only the video area on a screen having a wide aspect ratio and a subtitle in the blank area is moved into the video area. It is a signal processing device.

According to a first aspect of the present invention, a Y / C separation circuit for separating a luminance signal from a video signal, a border detection unit for detecting a border around the subtitle from the luminance signal, and a subtitle character according to a luminance level are displayed. A subtitle detection circuit that has a character detection unit that detects the subtitle, and that detects a portion in which both the border and the character are detected as a subtitle, and detects the subtitles inside and outside the video area to control the video size and subtitle movement. It is characterized by

According to a second aspect of the present invention, a Y / C separation circuit for separating a luminance signal from a video signal, and a video area detection circuit for detecting a start horizontal line position and an end horizontal line position of a video area from the brightness signal, A border detection unit that detects a border around the caption from the luminance signal, and a character detection unit that detects a character of the caption according to the luminance level,
A caption detection circuit that detects a portion where both edges and characters are detected as a caption, and a caption area detection circuit that detects a start horizontal line position and an end horizontal line position of the caption area by a signal output from the caption detection circuit, A video size that expands the video size to a wide aspect screen when there are no subtitles inside the video area or when there is subtitles only inside the video area, and a cinema size when the subtitles exist inside or outside the video area It is characterized by comprising a control circuit and a caption movement control circuit for controlling the caption to move into the video area when the caption exists only outside the video area.

According to a third aspect of the present invention, the above-mentioned caption detection circuit has a character detection circuit for detecting a character by sampling near a luminance peak level of the character.

A fourth aspect of the present invention is the video signal processing apparatus according to the second aspect, wherein the subtitle area detecting means determines whether or not the width of the detected subtitle area is within a certain range. It is characterized in that it comprises a determining means for performing.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a video signal processing device according to the present invention. The video signal processing apparatus according to the present embodiment receives a color video signal (standard video signal) of the NTSC system or the like and separates it into a luminance signal and a chroma signal.
A luminance level comparison circuit 2 for comparing the separated luminance signal with a predetermined threshold value to detect whether or not the luminance signal equal to or higher than the threshold value is included in the video signal, and the video start line position in the vertical direction based on the detection result. A video area detection circuit 3 that detects data and video end line position data, a caption detection circuit 4 that detects a caption from a luminance signal, and a caption area detection circuit 5 that detects caption start line position data and caption end line position data in the vertical direction. , A subtitle determination circuit 6, a video area detection circuit 3, and a subtitle area detection circuit 5, which determine the presence or absence of subtitles based on the data from the subtitle detection circuit 4.
A control circuit 7 is provided for determining the display mode of the video and instructing the subtitle movement based on the data from.

Further, a video size switching circuit 8 for switching the video size to be displayed on the display screen based on the determination by the control circuit 7, and a video center according to the video size to be displayed.
An image display circuit 9 that determines the position and displays an image, and a caption moving circuit 10 that controls the display position of the caption are provided.

A sync separation circuit 1 for extracting horizontal and vertical sync signals from the luminance components separated by the Y / C separation circuit 1.
1. It has a gate signal generation circuit 12 for generating various gate signals from the extracted horizontal and vertical synchronizations, and the gate signal generated by the gate signal generation circuit 12 is output to the video area detection circuit 3 and the subtitle area detection circuit 5. Is configured to.

FIG. 2 shows a block diagram of the caption detection circuit 4. The subtitle area detection circuit 4 detects a border around the characters of the subtitle, and a border detection circuit 41, which delays the border signal detected by the border detection circuit 41.
Delay circuit 42, character detection circuit 4 for detecting the characters of subtitles
3. Outputting the second delay circuit 44 for delaying the character signal detected by the character detection circuit 43, the first AND circuit 45 for taking the logical product of the signal output from the first delay circuit 42 and the character signal, and the second delay circuit 44 A second AND circuit 46 that takes the logical product of the signal and the trimming signal, and a logical sum of the signal that is output from the first AND circuit 45 and the signal that is output from the second AND circuit 46
It is composed of an R circuit 47.

FIG. 3 shows a block diagram of the subtitle determination circuit.
The caption determination circuit 6 includes a counter 61 that counts pulses from the signal of the caption detection circuit 4 as will be described later, a comparator 62 that compares the pulse to a certain value or more, and a case in which the comparator 62 drops below a certain value. The error processing circuit 63 outputs an error bit to the control circuit 7.

Next, the operation of this video signal processing device will be described. Now, as shown in FIG. 4, it is assumed that a video signal of a cinema video having blank areas above and below is input on a standard screen having an aspect ratio of "4: 3". a to b are upper blank areas, b to c are video areas, and c to f are lower blank areas. Then, subtitle areas d to e are present so as to cross the video end line c.

When this standard video signal is input, Y / C
The separation circuit 1 separates the luminance signal and outputs it to the luminance level comparison circuit 2, the caption detection circuit 4, and the synchronization separation circuit 11. The brightness level comparison circuit 2 outputs a part of the brightness signal equal to or higher than a predetermined threshold value to the video area detection circuit 3.

On the other hand, the sync separation circuit 11 extracts a horizontal sync signal and a vertical sync signal from the luminance component and outputs them to the gate signal generation circuit 12. In the gate signal generation circuit 12,
Various gate signals are created based on the horizontal and vertical synchronization signals and output to the video area detection circuit 3 and the subtitle area detection circuit 5.

The image area detection circuit 3 includes a brightness signal output from the brightness level comparison circuit 2 and a gate signal generation circuit 12
The start line and the end line of the video are detected based on the timing signal sent from the device, and the data of the detected both lines are output to the caption determination circuit 6 and the control circuit 7. For this, for example, a mask is preliminarily applied to the central portion in the horizontal direction where subtitles exist so that the luminance level of the signal in that portion becomes a predetermined threshold value. The subtitle area detection circuit 5 includes a luminance signal and gate signal generation circuit 12
The start position and the end position of the caption are detected by the gate signal output from.

The digital data sent from the Y / C separation circuit 1 to the caption detection circuit 4 is sent to the trimming detection circuit 41 and the character detection circuit 44, and after passing through the first and second delay circuits 42 and 45, respectively. , First and second AND circuits 4
It is sent to the OR circuit 47 through 3, 46.

When a caption exists so as to extend over the video end line c as shown in FIG. 4, the caption portion of the video area has the waveform shown in FIG. That is, this waveform is a trimming signal (pedestal signal) between the video signal and the character signal.
Is a configuration that exists. In general, when a caption is present in the video area, the periphery of the character is trimmed to be lower than the brightness level of the character or the video in order to distinguish the caption from the video for easy viewing. The peak of the brightness level of the character is beyond the brightness level of the image. Therefore, a threshold whose brightness level is set to be slightly higher than the trimming signal is set as K _1, and _one whose brightness level is lower than the threshold K ₁ is determined as a trimming signal. Further, a threshold value having a luminance level higher than that of the video signal and lower than that of the character signal is set as K ₂ , and a luminance level higher than the threshold value K ₂ is determined as a character signal.

The trimming detection circuit 41 detects a signal whose brightness level is less than or equal to the threshold value K ₁ as a trimming signal. Then, as shown in FIG. 6, a pulse waveform L ₁ whose pedestal portion is “H” is formed and output. On the other hand, the character detection circuit 43 detects a signal whose brightness level exceeds the threshold value K ₂ as a character signal, and the pulse waveform M in which the character signal portion becomes “H”.
Outputs ₁ . The pulse waveform L ₁ is input to the first delay circuit 42 and delayed to form the pulse waveform N ₁ . A pulse waveform O ₁ is obtained by taking the logical product of the pulse waveform M ₁ and the pulse waveform N _{1 in} the _first AND circuit 45. Next, the pulse waveform M ₁
Is delayed by the second delay circuit 44 to obtain the pulse waveform P ₁ .
The pulse waveform Q ₁ is obtained by taking the logical product of the pulse waveform L ₁ in the second AND circuit 46. Pulse waveforms O ₁ and Q ₁
Is ORed by the OR circuit 47 to obtain a pulse waveform R ₁ .

Further, when there is a subtitle in the blank area, as shown in the waveform of FIG. 7, there is no video signal but only a character signal. The edge detection circuit 41 detects a blank area having a threshold value K ₁ or less. In other words, it may be considered that the blank area is detected as the trimming portion. A pulse waveform L ₂ whose blank area becomes “H” is output. Further, the character detection circuit 43 outputs a pulse waveform M ₂ which sets the character signal portion whose brightness level exceeds the threshold value K ₂ to “H”. The pulse waveform L ₂ is delayed by the first delay circuit 42 to form the pulse waveform N ₂ . First AND circuit 4
When the logical product of the pulse waveform M ₂ and the pulse waveform N ₂ is calculated in 5, the pulse waveform O ₂ remains. Next, the pulse waveform M ₂ is
It is delayed by the delay circuit 44 to obtain the pulse waveform P ₂ and the _second waveform A 2
A pulse waveform Q ₂ is obtained by taking the logical product of the waveform L ₂ in the ND circuit 46. The pulse waveform O ₂ and Q ₂ ORs the OR circuit 47 to obtain a pulse waveform R _2.

A subtitle area detection circuit 5 detects the presence of two pulses in one horizontal scanning signal, such as the pulse waveforms R ₁ and R ₂ , and outputs the subtitle start line position and the subtitle end line position. . Thus, by providing the subtitle detection circuit 4 that detects a portion where both the border and the character are detected as a subtitle, the subtitle in the video area can be accurately detected without being affected by the video signal.

The pulse output from the above-mentioned caption detection circuit 4 is counted by the counter 61 of the caption determination circuit 5, and the comparator 62 compares whether or not it is below a certain value. If the value is less than a certain value, the error processing circuit 52 performs error processing as an erroneous detection. That is, an error bit is set, and at that time, the control circuit 7 determines that there is no caption and does not take in the signal from the caption area detection circuit 5.

The control circuit 7 is composed of a video size control section 7a and a caption movement control section b. Next, these will be described in detail. FIG. 9 shows an image size control section 7a of the control circuit 7.
FIG. In the figure, the data continuous coincidence determination unit 61 receives the video start line position data b and the video end line position data c of the current field from the video area detection circuit 3 and compares them with the data of the previous field. Then, it is detected whether the read data match. Then, the coincidence data for a predetermined number of fields is counted and registered in the counter, and the coincidence data for a predetermined number or more are output as the finalized data b and c.

The arithmetic unit 63 is a data continuous coincidence determination unit 61.
From the determined data b and c, the difference h = c−b is calculated. The comparison unit 64 compares the input data b, c with the determination reference data bk, ck for determining the image start line and the image end line stored in the determination reference data storage unit. The judgment reference data setting unit 66 sets the data stored in the judgment reference data storage unit, and is not particularly provided if all the necessary data is written in the judgment reference data storage unit 65 in advance by some method. Is also good.

The comparison section 67 compares the input data h regarding the number of effective lines with the data regarding the number of effective lines stored in the determination reference data storage section 68 by the determination reference data setting section 69. The determination unit 70 includes a comparison unit 64.
Also, based on the comparison result of the comparison unit 67, it is determined whether the input video signal is a standard video signal or a cinema video signal. Further, as will be described later, the caption movement control circuit 7b receives a signal indicating the position of the caption and determines the video size. The switching signal generation unit 71 receives the determination result of the determination unit 70 and generates a switching control signal for switching the video size switching circuit 8. In this way, the video size switching circuit 7 switches the video size in response to the signal from the switching signal generator 71, and the video display circuit 9 determines the video center position according to the video size.

Next, the operation of the image size control section 7a will be described with reference to the flow chart shown in FIG.
The processing shown in this flow chart is performed for a predetermined field period at every cycle of one field cycle (about 16.7 ms) or more of the NTSC signal. The image start line position data a and the image end position data b are read from the image area detection circuit 3, and the data read one cycle before by the data continuous coincidence determination unit 61 and the data read this time are compared. , Perform continuous data determination. When the data match, the number of matches in each cycle is counted, and the data matched a predetermined number of times are output as the finalized data b and c (step S1).

In order to make the judgment reference value of the picture signal judgment have a hysteresis width for each picture size, the following processing steps are
It is different depending on the current video size mode (step S2).

In the comparison unit 64, the data continuous coincidence determination unit 61
By comparing the output data b, c from the reference data with the reference data, it is determined from the video start line position data b whether there is a blank portion above the video (steps S3, S).
6). Here, for example, when it is determined that there is no blank when b <20, the determination reference value has a hysteresis width such that b <21 in step S3 and b <19 in step S6. The fluctuation can be suppressed. When it is determined that there is no blank in steps S3 and S6, the determination unit 70 determines that the video signal is a standard video signal.

Similarly, the comparator 64 determines from the image end line position data b whether or not there is a blank portion under the image (steps S4 and S7). Here, for example, c
When it is determined that there is no blank in <245, step S4
It is possible to suppress the fluctuation of the judgment result due to the fluctuation of the data by giving the judgment reference value a hysteresis width such that b <244 in step S7 and b <251 in step S7. If it is determined in steps S4 and S7 that there is no blank, the video signal is determined to be a standard video signal.

Further, the number of effective video lines h (= c−b) calculated from the image start line position data b and the image end line position data c by the calculation unit 63 and the determination reference data storage unit 68 are stored. The image determination is performed by comparing with the determination reference data (step S5, step S8). Here, for example, in step S55, 131 <
By making the judgment reference value have a hysteresis width such that h <219 and 129 <h <221 in step S8, fluctuation of the judgment result due to fluctuation of data can be suppressed.

When the video signal is determined to be the standard video signal in steps S3 to S8, the switching signal generator 71 generates the switching signal so as to switch to the video size mode suitable for the standard video signal (step S10). Then, the video size switching circuit 8 is switched and controlled. When the video signal is determined to be a cinema video signal as a result of steps S5 and S8 (step S9), it is determined in which area the subtitle exists from the signal from the subtitle control unit 7b (step S11). ~ 12). Only when the subtitle exists in the video area and the blank area, the video size mode suitable for the cinema video signal is switched (step S13). Also, if there is no subtitle, or if there is subtitle only in the blank area or only in the video area,
The video size is switched to the video size mode in which the wide aspect screen is set (step S14).

A switching signal is generated from the switching signal generator 71 to control the video size switching circuit 8. Further, after the counter 62 for continuous data coincidence determination is initialized (step S11), a series of processing is ended.

Next, FIG. 11 shows a block diagram of the caption movement control circuit. In the figure, the data continuous coincidence determination unit 72
Receives the subtitle start line position data d and the subtitle end line position data e of the current field from the subtitle area detection circuit 5, compares it with the data of the immediately preceding field, and determines whether the read data matches. To determine. And
The coincidence data for a predetermined number of fields is counted, registered in the counter 73, and coincident for a predetermined number or more is output as definite data d, e.

The calculation section 74 is a data continuous coincidence determination section 72.
From the data size coincidence determination section 61 of the video size control section 7a. First, i = c-
Calculate d. At this time, if the subtitle start line d does not exist from the subtitle area detection circuit 5, d is set to 0. The determination unit 78 determines the area where the subtitle exists from the result of i, and determines whether to move the subtitle. The control signal generation unit 79 determines the subtitle moving circuit 1 based on the determination result of the determination unit 78.
Instruct 0 to move subtitles.

Further, the calculation section 74 includes a video size control section 7
Based on the fixed position data c of the video end line output from the data continuous match determination unit 61 of a, c + 1, c- {e-
(C + 1)} is calculated, and the control signal generator 79 instructs the moving position to the subtitle moving circuit 10 based on this result. The subtitle moving circuit is composed of a moving IC and a memory, and by giving an instruction to the moving IC from the control signal generating unit 79, the subtitle is moved to perform subtitle display.

Next, FIG. 12 shows a flowchart of the subtitle size reduction processing of the subtitle movement control unit 76. In the figure,
Subtitle start line position data d from the subtitle area detection circuit 5
And the subtitle end position data e are read. The subtitle start line position data d and the subtitle end position data e read one cycle before by the data continuity determination unit 72 are compared with the subtitle start line position data d and the subtitle end position data e read this time. , Perform continuous data determination. If the data match, the number of matches in each cycle is counted, and the data matched a predetermined number of times is output as the finalized data d and e (step S21).

In the calculation unit 74, the data continuous coincidence determination unit 72
Output confirmation data d from the data continuous coincidence determination unit 61
I = c−d is calculated from the output confirmation data c from (step S22). In the case of i = c, since d = 0 and there is no subtitle (step S23), the subtitle is not moved (step S27). If i> 0, the subtitle exists in the video area with c> d, and thus the subtitle is not moved (step S27). In the case of i <0, since c <d and the subtitle exists only in the blank area, the subtitle is moved (step S2).
6). The control signal generator 79 outputs a control signal for instructing the moving position to the subtitle moving circuit 10, clears the counter for continuous data matching in step S28, and ends the series of processes.

FIG. 13 shows a flowchart of the subtitle movement position determining process of the subtitle movement control unit 7b. The data c at the video end line position and the data e at the subtitle end position are read.
At this time, these data are confirmed data by comparing the data read one cycle before and the data read this time, and determining the continuous coincidence of the data (step S
31).

When the caption is moved according to the instruction of the judgment unit 78 which judges that there is a caption (step S32), the control signal generation unit 79 inputs the caption data of c + 1 or less to the write address in the memory of the caption moving circuit 10. An instruction is issued (step S33). Next, the read address is c
An instruction to set − {e− (c + 1)} is issued (step S3
4). When reading from the read address, subtitle data of c + 1 or less of the write address is c- {e- (c +
1)} The following subtitle data is instructed to be read (step S35), and the subtitle moving circuit is turned on (step S36). When subtitles are not moved according to the instruction from the determination unit 78 that determines that there is no subtitle (step S3
2), the control signal generator 79 turns off the caption moving circuit 10.
I do. In step S38, the data continuous coincidence counter is cleared, and the series of processes is completed.

The control signal from the control circuit 7 is input to the moving IC of the caption moving circuit 10, and the memory is instructed to write, read, and move the caption at a predetermined position and size.

In this way, the video size is expanded to the wide aspect screen when there is no subtitle in the video area and when the subtitle exists only in the video area, and the video size is set to the cinema video when there are subtitles inside and outside the video area. age,
If subtitles exist only outside the video area, the subtitles are controlled so that they are moved within the video area.Therefore, subtitles do not overlap within the video area due to movement, and optimal video size and subtitle movement control are possible. It will be possible.

FIG. 14 shows another embodiment of the caption detection circuit. This circuit has basically the same configuration as that of the caption detection circuit 4 described above, and is different in that a character data sampling circuit 48 is added. The character data sampling circuit 48 samples the vicinity of the brightness peak level of the character from the brightness signal and outputs it to the character detection circuit 44. That is, as shown in FIG. 15, x to z are defined as the range in which the luminance peak level y of the character exists, and this range is sampled. The brightness peak level y detected in this range is output to the character detection circuit 44. Since the operation of the caption detection is the same as that of the caption detection circuit 4 described above,
Description is omitted.

In this way, character detection is performed by sampling a certain range of the brightness level, so that erroneous detection can be prevented and accurate detection can be performed. For example, as shown in A of FIG. 15, when the luminance level exceeds the luminance peak level of the character like the video signal b, if the character data sampling circuit 48 is not provided, the character becomes as shown in B of FIG. The detection circuit 44 also picks up the video signal b. However, when the character data sampling circuit 48 is provided, C of FIG.
Like, it is possible to detect the character accurately.

FIG. 16 shows another example of the subtitle movement control section 7b. This subtitle movement control circuit 7b is configured to include a subtitle determination comparison unit 80 between the calculation unit 74 and the determination unit 78, and the other portions are the same as the above-described subtitle movement control unit 7b. The calculation unit 74 calculates the range ed of the subtitle area and outputs it to the subtitle determination comparison unit 80. The subtitle determination comparison unit 80 compares and determines whether the calculated subtitle area exists in the effective range. For example, the judgment values s and t are set, and s <ed
When <t, it is determined that the subtitle detection data is valid, and the subtitle movement control circuit 7b is operated as described above. If it is not within this range, it operates as if there is no subtitle.

In this way, malfunction due to erroneous detection of the subtitle area detection circuit 5 can be prevented, and accurate video size and subtitle movement can be controlled.

[0061]

According to the first aspect of the present invention, since the subtitle detection circuit for detecting the portion where both the edge and the character are detected as the subtitle is provided, the subtitle in the video area can be accurately detected. It is possible to control video size and subtitle movement without malfunction.

According to the second aspect of the present invention, the control circuit expands the video size to a wide aspect screen when there is no subtitle in the video area and when there is a subtitle only in the video area. If there are subtitles in, the video size is set to cinema video, and if subtitles exist only outside the video area, the subtitles are controlled to move into the video area. Therefore, moving subtitles causes subtitles to overlap in the video area. Of course, it is possible to control the optimal video size and subtitle movement.

According to the third aspect of the present invention, the subtitle detection circuit has a character detection circuit for detecting a character by sampling the vicinity of the luminance peak level of the character. Therefore, the video signal in the video area may be erroneously detected. It becomes low, and accurate subtitle detection becomes possible.

According to the fourth aspect of the present invention, the subtitle area detecting means includes the determining means for determining whether or not the width of the detected subtitle area is within a certain range. Malfunction due to detection can be prevented, and accurate video size and subtitle movement can be controlled.

[Brief description of drawings]

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

FIG. 2 is a block diagram showing an embodiment of the caption detection circuit shown in FIG.

FIG. 3 is a block diagram showing an embodiment of the caption determination circuit shown in FIG.

FIG. 4 is an explanatory diagram showing a cinema image in which subtitles exist.

FIG. 5 is an explanatory diagram showing a signal waveform around a caption in a video area.

FIG. 6 is an explanatory diagram showing a detection operation waveform of a caption detection circuit.

FIG. 7 is an explanatory diagram showing a signal waveform around a caption in a blank area.

FIG. 8 is an explanatory diagram showing a detection operation waveform of a caption detection circuit.

FIG. 9 is a block diagram showing an embodiment of a video size control circuit.

FIG. 10 is a flowchart showing an operation of determining a video size of a video size control circuit.

FIG. 11 is a block diagram showing an embodiment of a caption movement control circuit.

FIG. 12 is a flowchart showing an operation of determining subtitle movement of a subtitle movement control circuit.

FIG. 13 is a flowchart showing a subtitle movement operation of the subtitle movement control circuit.

FIG. 14 is a block diagram showing another embodiment of a caption detection circuit.

FIG. 15 is an explanatory diagram showing caption detection of this caption detection circuit.

FIG. 16 is a block diagram showing another embodiment of the caption movement control circuit.

FIG. 17 is a block diagram showing an example of a conventional video signal processing device.

FIG. 18 is an explanatory diagram showing movement of subtitles in a conventional video signal processing device.

[Explanation of Codes] 1 Y / C separation circuit 2 Luminance level comparison circuit 3 Video area detection circuit 4 Caption detection circuit 5 Caption area detection circuit 6 Caption determination circuit 7 Control circuit 8 Video size switching circuit 9 Video display circuit 10 Caption moving circuit 11 Sync Separation Circuit 12 Gate Signal Generation Circuit 41 Edge Detection Circuit 42 First Delay Circuit 43 First AND Circuit 44 Character Detection Circuit 45 Second Delay Circuit 46 Second AND Circuit 47 OR Circuit

Claims (4)

[Claims] 1. A video signal processing apparatus for expanding a cinema image having blank areas at the top and bottom to display only the video area on a screen having a wide aspect ratio and moving subtitles in the blank area into the video area. A Y / C separation circuit that separates a luminance signal, a border detection unit that detects a border around the caption from the luminance signal, and a character detection unit that detects a character of the caption based on the luminance level. A video signal processing device, comprising: a caption detection circuit that detects a portion in which both are detected as a caption, and detects captions inside and outside the video area to control the video size and caption movement. 2. A video signal processing apparatus for expanding a cinema image having blank areas at the top and bottom to display only the video area on a screen having a wide aspect ratio and moving subtitles in the blank area into the video area. A Y / C separation circuit that separates a luminance signal, a video area detection circuit that detects a start horizontal line position and an end horizontal line position of a video area from the brightness signal, and a border around the caption from the brightness signal A trimming detection unit and a character detection unit that detects a character of a subtitle according to the brightness level, a subtitle detection circuit that detects a portion where both the trimming and the character are detected as a subtitle, and a signal output from the subtitle detection circuit. The subtitle area detection circuit that detects the start horizontal line position and end horizontal line position of the subtitle area by A video size control circuit that expands the video size to a wide aspect screen when there are no subtitles and when there are subtitles only in the video area, and a cinema size when the subtitles exist inside and outside the video area. A video signal processing device, comprising: a subtitle movement control circuit that controls to move the subtitle into the video area when the subtitle exists only outside the video area. 3. The video signal processing device according to claim 1, wherein the caption detection circuit includes a character detection circuit that samples a character near a luminance peak level to detect the character. 4. The video signal processing apparatus according to claim 2, further comprising a determining unit that determines whether or not the width of the detected subtitle area is within a certain range by the subtitle area detecting unit.