JP2004221750A - Osd receiver - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an OSD receiver capable of obtaining an image output signal with the best image quality at all times by applying optimum image quality correction to an image/OSD signal. <P>SOLUTION: The optimum image quality correction is applied to the image/OSD signal by detecting the OSD area of the image/OSD signal, an OSD font, an ODS luminance level, an image signal luminance level and motion information of image information. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an OSD display receiver that converts an image signal into a scanning line and processes an image / OSD signal on which an OSD (On Screen Display) signal is superimposed.
[0002]
[Prior art]
A conventional OSD display receiver will be described with reference to FIG. FIG. 7 is a block diagram showing a main configuration of an OSD display receiver according to the related art.
[0003]
The image / OSD signal 6 output from the image / OSD processing device 1 for superimposing the OSD signal on the image signal is subjected to image quality correction by the image processing device 2. The image / OSD signal 6 is subjected to image quality correction by a black expansion circuit 20, a dark part gamma circuit 22, a bright part gamma circuit 24, an image quality circuit 26, a contrast circuit 27, a black level circuit 28, and a gamma circuit 30, and an image output signal 17 is obtained. However, the image quality correction circuit in the image processing device 2 performs an operation of automatically performing the optimum correction according to the luminance level of the image signal. Here, the actual image signal is a signal on which no OSD signal is superimposed. However, the image / OSD signal 6 on which the OSD is superimposed by the image / OSD processing device 1 is subjected to image quality correction by the image processing device 2. ing.
[0004]
The above-described prior art shows an example of a general image processing method in which the processing of the present invention is not performed. As a prior art similar to the gist of the present invention, the size of an OSD signal and the like are considered. There is known an apparatus that can reduce chroma noise by detecting the image and thereby ensure an image quality state according to various OSD information display screens (for example, Patent Document 1).
[0005]
The differences between the technology disclosed in Patent Document 1 and the present invention and the superiority of the present invention will be described.
[0006]
According to the technique described in Patent Document 1, in the case of a signal in which an OSD is superimposed on an image, the OSD signal is switched to a system via a filter by detecting the size, number, and definition of the OSD signal, and chroma noise is detected. Is reduced. As a result, it is possible to always maintain a favorable image quality state according to various OSD information display screens.
[0007]
On the other hand, according to the present invention, in the case of a signal in which an OSD is superimposed on an image, the luminance level information (OSD level) Information, that is, information on OSD embedded in an image or OSD superimposed on an image) is added, and there is a difference in that a means for detecting OSD information based on three-dimensional factor information is provided. Further, the present invention has a means for detecting not only means for detecting OSD information but also luminance level information and motion information of a background image for displaying the OSD, and an optimum image / OSD image quality corresponding to the background image. There is also a difference in the point that they are secured. OSD signals include an OSD embedded in an image and an OSD to be superimposed on an image, and both have a difference in luminance level. In other words, the luminance level information of the background image and the information obtained from the motion information are image information. In the case of the OSD embedded in the image and the case of the OSD superimposed on the image, Although accurate image control cannot be performed due to the difference in luminance level, the detection means according to the present invention makes it possible to secure an optimum image quality according to the background image state / OSD state.
[0008]
[Patent Document 1]
JP 2001-346072 A
[Problems to be solved by the invention]
In the conventional configuration shown in FIG. 7 and described above, the image / OSD signal 6 is subjected to image quality correction by the image processing device 2 and the OSD signal is determined to be an image signal. On the other hand, improper image quality correction is performed, resulting in deterioration of the image signal 5 such as a floating black level and image quality deterioration such as an OSD display being difficult to see. The degree of the influence of the image quality deterioration varies depending on the magnitude of the OSD signal and the luminance level of the image signal 5. This will be described with reference to FIG.
[0010]
The image pattern (1) shown in FIG. 6 is OSD area small / font small / image dark, and the image pattern (2) is OSD area large / font small / image dark. When the image quality is corrected by the device 2, the luminance level of the image pattern 5 part slightly floats in the image pattern (1), and the luminance level of the image signal 5 part largely floats in the image pattern (2). Accordingly, the visibility of the OSD display also changes, and further, it changes according to the change in the luminance level of the image signal 5 portion.
[0011]
In the general image processing apparatus 2, the black expansion circuit 20, the dark part gamma circuit 22, the light part gamma circuit 24, the contrast circuit 27, and the black level circuit 28 use the image signal 5 in one field to detect the image signal 5. And the image quality circuit 26 and the gamma circuit 30 perform static correction without performing correction in accordance with the image signal 5. Therefore, the detection result of one field changes depending on the OSD area such as the image patterns {circle around (1)} to {circle around (4)} shown in FIG. Will change. Further, when the luminance level of the detection result is high, the image output signal 17 is determined by the OSD area, the OSD font, the OSD luminance level, and the image signal luminance level. The image quality of the image signal and the OSD signal is deteriorated.
[0012]
The present invention has been made in order to solve the above-mentioned problems of the related art, and detects an OSD area, an OSD font, an OSD luminance level, and an image signal luminance level of an image / OSD signal 6 to obtain an image. An object of the present invention is to provide an OSD display receiver capable of performing the optimum image quality correction on the / OSD signal 6 and always obtaining the image output signal 17 with the best image quality.
[0013]
[Means for Solving the Problems]
In order to achieve the above object, according to one aspect of the present invention, an image / OSD signal output from an image / OSD processing device that superimposes an OSD signal on an image signal is adjusted in image quality by the image processing device, and the image output signal is output. In the obtained OSD display receiver,
A dark part detection circuit for detecting a dark part area of the image / OSD signal;
A bright portion detection circuit for detecting a bright portion area of the image / OSD signal;
A first luminance level comparison circuit that compares a detection result of the dark part detection circuit with a detection result of the light part detection circuit;
A black detection circuit for detecting a black area of the image / OSD signal;
A second luminance level comparison circuit that compares a detection result of the black detection circuit with a comparison result of the first luminance level comparison circuit;
An ABL circuit that detects the brightness of the image output signal and controls a brightness level according to the brightness of the image output signal;
A third brightness level comparison circuit that compares a detection result of the ABL circuit with a comparison result of the second brightness level comparison circuit;
A first OSD information comparison circuit for comparing an OSD font information signal from the image / OSD processing device with an OSD area information signal from the image / OSD processing device;
A second OSD information comparison circuit that compares an OSD level information signal from the image / OSD processing device with a comparison result of the first OSD information comparison circuit;
Have
Image correction level control weighted and synthesized by an image correction level control circuit based on a luminance level detection signal obtained by the third luminance level comparison circuit and an OSD information detection signal obtained by the second OSD information comparison circuit Changing the image correction level control bus signal to the image processing apparatus according to the signal to perform image quality correction according to the luminance level, OSD magnitude, and OSD luminance level of the image / OSD signal;
It is configured as follows.
In another invention according to the present application,
A first control level determination circuit that compares the luminance level detection signal obtained by the third luminance level comparison circuit with the OSD information detection signal obtained by the second OSD information comparison circuit;
An image motion detection circuit that counts a motion amount detection signal obtained by an IP conversion circuit from the image / OSD processing device and determines a still image / moving image based on a certain threshold value;
A second control level determination circuit that compares a determination result of the first control level determination circuit with a determination result of the image motion detection circuit;
Have
The image correction level control bus signal to the image processing apparatus is changed by the weighted and synthesized image correction level control signal obtained by the second control level determination circuit, so that the image brightness level of the image / OSD signal is changed. Perform image quality correction according to OSD size, OSD luminance level, and motion amount.
It is configured as follows.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of an OSD display receiver according to the present invention will be described with reference to the drawings. 1 to 6 relate to an embodiment of the present invention (hereinafter, referred to as the present embodiment), FIG. 1 is a block diagram showing a main configuration of an OSD display receiver of the present embodiment, and FIG. 3 is a block diagram showing details of an OSD information detection circuit in FIG. 1, FIG. 4 is a block diagram showing details of an image correction level control circuit in FIG. 1, and FIG. FIG. 5 is a table showing an example of the algorithm of the present embodiment, and FIG. 6 is an explanatory diagram showing a performance difference between the present embodiment and the conventional technology.
[0015]
As shown in FIG. 1, the OSD display receiver according to the present embodiment includes an image / OSD processing device 1, an image processing device 2, an image control device 3, and a microcomputer circuit 4.
[0016]
The image / OSD processing device 1 includes an IP conversion circuit 18 and an OSD mixing circuit 19.
[0017]
Further, the image processing device 2 includes a black extension circuit 20, a black detection circuit 21, a dark portion gamma circuit 22, a dark portion detection circuit 23, a light portion gamma circuit 24, a light portion detection circuit 25, and an image quality circuit 26. , A contrast circuit 27, a black level circuit 28, an ABL (Auto Brightness Limiter) circuit 29, and a gamma circuit 30.
[0018]
The image control device 3 includes an image luminance level detection circuit 31, an image motion detection circuit 33, an OSD information detection circuit 35, and an image correction level control circuit 37.
[0019]
The image signal 5 input to the image / OSD processing device 1 is subjected to a scanning line conversion by an IP conversion (interlace → progressive conversion) circuit 18 and is converted into an image / OSD signal 6 on which OSD information is superimposed by an OSD mixing circuit 19. Are output to the image processing apparatus 2.
[0020]
First, the image brightness level detection circuit 31 of the image control device 3 will be described. The image / OSD signal 6 is subjected to black detection (detection of the black area of the image / OSD signal 6) for each field by the black detection circuit 21 to correct the black expansion circuit 20 according to the black detection result. A black detection signal 10 is obtained. Further, the dark portion detection circuit 23 performs a dark portion detection operation (detection of the dark portion area of the image / OSD signal 6) for each field, corrects the dark portion gamma circuit 22 according to the dark portion detection result, and outputs the dark portion detection signal 9. obtain. Also, the bright portion detection circuit 25 performs a bright portion detection operation (detection of the bright portion area of the image / OSD signal 6) for each field, and corrects the bright portion gamma circuit 24 according to the bright portion detection result. A bright part detection signal 8 is obtained. The image / OSD signal 6 passed through the bright part gamma circuit 24 is further subjected to image quality correction by an image quality circuit 26, a contrast circuit 27, a black level circuit 28, and a gamma circuit 30. The contrast circuit 27 and the black level circuit 28 are corrected by an ABL circuit 29 for detecting the brightness level of the image output signal 17 for each field, and the brightness level is corrected according to the brightness of the image output signal 17. An ABL detection signal 7 indicating the level of the brightness of the image output signal 17 is obtained from the ABL circuit 29 that performs.
[0021]
The black detection signal 10, the dark part detection signal 9, the bright part detection signal 8, and the ABL detection signal 7 obtained by these image luminance level detection operations are input to an image luminance level detection circuit 31, and the detection result of the image luminance level is obtained. , An image luminance level detection signal 32 is obtained.
[0022]
FIG. 2 shows the configuration of the image luminance level detection circuit 31 that outputs the image luminance level detection signal 32. In the image luminance level detection circuit 31 of FIG. 2, reference numeral 40 denotes a first luminance level comparison circuit; Is a second luminance level comparison circuit, and 44 is a third luminance level comparison circuit.
[0023]
The dark part detection signal 9 and the light part detection signal 8 are input to a first luminance level comparison circuit 40 to obtain a luminance level detection signal "1" 41 as a comparison result, and the black detection signal 10 and the luminance level detection signal "1" 41 is input to a second brightness level comparison circuit 42 to obtain a brightness level detection signal “2” 43 as a comparison result, and the ABL detection signal 7 and the brightness level detection signal “2” 43 are converted to a third brightness level comparison circuit. The image brightness level detection circuit 32 outputs the image brightness level detection signal 32 as a detection result of the image brightness level. .
[0024]
An example of an algorithm for comparison and detection by the image luminance level detection circuit 31 is shown in (1) of FIG. In FIG. 5, for convenience, it is expressed by a numerical expression, but the actual configuration can be realized by a threshold value of a DC voltage or digital processing. The threshold value of the dark portion detection signal 9 input to the first luminance level comparison circuit 40 is set to a dark signal, an intermediate signal, and a bright signal. Similarly, the bright portion detection signal 9 is also a dark signal, an intermediate signal, and a bright signal. A threshold is set for the signal. For example, if the dark part detection signal 9 is “dark” and the light part detection signal 8 is “dark”, a result of “0” is obtained. The result is expressed in three stages of '0' to '2', and a threshold expression result of darker as '0' and brighter as '2' is obtained. Similarly, the second luminance level comparison circuit 42 and the third luminance level comparison circuit 44 perform the same operation, whereby the third luminance level comparison circuit 44 finally obtains the luminance level detection signal 32. .
[0025]
Next, the OSD information detection circuit 35 of the image control device 3 will be described. An OSD font information signal 12, an OSD area information signal 13, and an OSD level information signal 14 are input to the OSD information detection circuit 31 as OSD information synthesized by the OSD mixing circuit 19, and as an OSD information detection result, an OSD information detection signal is output. 36.
[0026]
FIG. 3 shows the configuration of the OSD information detection circuit 35 that outputs the OSD information detection signal 36. In the OSD information detection circuit 35 of FIG. 3, reference numeral 45 denotes a first OSD information comparison circuit, and 47 denotes a second OSD information comparison circuit. Is an OSD information comparison circuit.
[0027]
The OSD font information signal 12 and the OSD area information signal 13 are input to a first OSD information comparison circuit 45 to obtain an OSD information detection signal “1” 46 as a comparison result, and the OSD level information signal 14 and the OSD information detection signal “ "1" 46 is input to the second OSD information comparison circuit 47 to obtain an OSD information detection signal 36 as a comparison result, whereby the OSD information detection circuit 35 outputs the OSD information detection signal 36 as the OSD information detection result. Output.
[0028]
An example of an algorithm for comparison and detection by the OSD information detection circuit 35 is shown in (2) of FIG. In FIG. 5, for convenience, it is expressed by a numerical expression, but the actual configuration can be realized by a threshold value of a DC voltage or digital processing. The threshold of the OSD font information signal 12 input to the first OSD information comparison circuit 45 is set to a small signal, an intermediate signal, and a large signal. Similarly, the OSD area information signal 13 is also a small signal, an intermediate signal, and a small signal. A threshold is set for a large signal. For example, if the OSD font information signal 12 is “small” and the OSD area information signal 13 is “small”, a result of “0” is obtained. The result is expressed in five stages from '0' to '4', and a threshold expression result that is smaller as '0' and larger as '4' is obtained.
[0029]
The OSD information detection signal “1” 46 and the OSD level information signal 14 are input to the second OSD information comparison circuit 47, and the OSD information detection signal 36 as the OSD information detection result is obtained as a comparison result. The level information signal 14 is processed by a threshold expression in which the case of the OSD embedded in the image signal 5 is BLK and the case of the added OSD is HF. Since the screen is brighter in BLK than in HF, it is 1 in HF. Get a result with a lower point.
[0030]
Next, the image motion detection circuit 33 of the image control device 3 will be described. The motion amount detection signal 11 obtained when the image signal 5 is subjected to scanning line conversion by the IP conversion circuit 18 is input to the image motion detection circuit 33. Since the motion amount detection signal 11 is information on a pixel basis, whether the signal is closer to a still image or a signal closer to a moving image in one field is counted by a counter that sets a threshold value. The binary determination result of the image and the moving image is obtained as the image motion amount detection signal 34.
[0031]
Next, the image correction level control circuit 37 of the image processing device 3 will be described. The image brightness level detection signal 32, the OSD information detection signal 36, and the image motion amount detection signal 34 are input to an image correction level control circuit 37, and an image correction level control signal 15 is obtained as an image quality correction level control result. It has become.
[0032]
FIG. 4 shows the configuration of the image correction level control circuit 37 that outputs the image correction level control signal 15. In the image correction level control circuit 37 of FIG. 4, reference numeral 50 denotes a first control level determination circuit; Is a second control level determination circuit.
[0033]
The image brightness level detection signal 32 and the OSD information detection result 36 are input to a first control level determination circuit 50 to obtain a control level determination signal "1" 51 as a comparison result. The level determination signal “1” 51 is input to a second control level determination circuit 52 to obtain an image correction level control signal 15 as a comparison result, whereby the second control level determination circuit 52 generates an image quality control result. An image correction level control signal 15 is output.
[0034]
An example of an algorithm for comparison and detection by the image correction level control circuit 37 is shown in (3) of FIG. In FIG. 5, for convenience, it is expressed by a numerical expression, but the actual configuration can be realized by a threshold value of a DC voltage or digital processing. The OSD information detection signal 36 input to the first control level determination circuit 50 includes the magnitude of the OSD and the luminance level information, and is set with a threshold value in five stages from '0' to '4'. The threshold value is as small as 0's and dark, and as large as 4's. Similarly, the image brightness level detection signal 32 is also set with threshold values in three levels from '0' to '2', and the threshold value is darker as '0' and brighter as '2'. For example, if the OSD information detection signal 36 is "0" and the image luminance level detection signal 32 is "0", a result of "0" is obtained as the control level determination signal "1" 51. The result is expressed in 15 steps from '0' to '14', and a threshold expression result that the OSD is smaller, the OSD is darker, and the luminance level is darker as 0 is obtained.
[0035]
The second control level determination circuit 52 receives the image motion amount detection signal 34 and the control level determination signal "1" 51, which is the result of the above-described 15-step pattern, and if the image is a still image, the control level The determination signal “1” 51 is output to the microcomputer circuit 4 as an image correction level control signal 15, and image quality correction control is performed according to a 15-step pattern obtained by the image correction level control signal 15. A process for not performing the correction control is performed.
[0036]
When the image correction level control signal 15 which is a result of the above-described 15-step pattern is input, the microcomputer circuit 4 performs image-correction-level control in order to perform image quality correction according to the above-described 15-step pattern. The bus signal 16 controls the image quality correction of the black expansion circuit 20, dark part comma circuit 22, bright part gamma circuit 24, image quality circuit 26, contrast circuit 27, black level circuit 28, and gamma circuit 30.
[0037]
Further, when it is determined that the moving image is a moving image, the microcomputer circuit 4 is expected to change the scene sharply, and the luminance level may frequently change. Then, a malfunction or a real-time screen luminance change occurs, and a stable screen cannot be provided. Therefore, processing using the motion amount detection signal 34 is performed.
[0038]
From the above operation, in a receiver that performs image quality processing on an image signal on which an OSD signal is superimposed and displays the image signal, a detailed determination process combining an image luminance level detection result, an OSD information detection result, and an image motion amount detection result is performed. In addition, since a process for performing adaptive image quality control is performed, it is possible to overcome the drawbacks of the conventional technology, and it is possible to always obtain a good image / OSD image quality irrespective of the image luminance level and the OSD state. It becomes possible to realize a display receiver.
[0039]
FIG. 6 shows a diagram comparing the effect of the present embodiment (the present invention) with the conventional technology. The image pattern (1) of the image / OSD signal is OSD area small / font small / image dark, and the image pattern (2) is OSD area large / font small / image dark. Inappropriate image quality correction is performed on the image of the signal 5 to cause deterioration of the image signal 5 such as a floating black level, and image quality deterioration such as an OSD display being difficult to see. By detecting the area, the OSD font, the OSD luminance level, and the image signal luminance level and performing image quality correction according to the detection result, it is possible to realize an OSD display receiver that always obtains the image output signal 17 having the best image quality. .
[0040]
【The invention's effect】
As described above, according to the present invention, an image / OSD signal output from an image / OSD processing device that superimposes an OSD signal on an image signal is adjusted in image quality by the image processing device to obtain an image output signal. According to the image brightness level detection result, the image correction level control bus signal to the image processing device, the image correction level control signal obtained by weighting and combining the brightness level detection result in the image correction level control circuit, By changing the image correction level control bus signal, image quality correction according to the luminance level of the image / OSD signal can be performed.
[0041]
Further, according to the OSD information detection result, the image correction level control signal obtained by weighting and combining the OSD information detection result with an image correction level control circuit with respect to the image correction level control bus signal to the image processing apparatus is provided. By changing the image correction level control bus signal, image quality correction according to the OSD magnitude and OSD luminance level of the image / OSD signal can be performed.
[0042]
Further, according to the image brightness level detection result and the OSD information detection result, an image correction level control signal obtained by weighting and synthesizing an image correction level control bus signal to the image processing apparatus by an image correction level control circuit. By changing the image correction level control bus signal, it is possible to perform image quality correction in accordance with the luminance level, OSD size, and OSD luminance level of the image / OSD signal.
[0043]
Further, the image correction level control circuit weights and synthesizes the image correction level control bus signal to the image processing apparatus according to the image luminance level detection result, the OSD information detection result, and the image motion amount detection result. By changing the image correction level control bus signal according to the image correction level control signal, it is possible to perform image quality correction according to the image luminance level, the OSD size, the OSD luminance level, and the amount of motion of the image / OSD signal.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a main configuration of an OSD display receiver according to an embodiment of the present invention.
FIG. 2 is a block diagram showing details of an image luminance level detection circuit in FIG. 1;
FIG. 3 is a block diagram showing details of an OSD information detection circuit in FIG. 1;
FIG. 4 is a block diagram showing details of an image correction level control circuit in FIG. 1;
FIG. 5 is a table showing an example of an algorithm in the OSD display receiver according to one embodiment of the present invention.
FIG. 6 is an explanatory diagram showing a performance difference between an OSD display receiver according to an embodiment of the present invention and a conventional OSD display receiver.
FIG. 7 is a block diagram showing a configuration of a main part of a conventional OSD display receiver.
[Explanation of symbols]
Reference Signs List 1 image / OSD processing device 2 image processing device 3 image control device 4 microcomputer circuit 5 image signal 6 image / OSD signal 7 ABL detection signal 8 bright portion detection signal 9 dark portion detection signal 10 black detection signal 11 motion amount detection signal 12 OSD font Information signal 13 OSD area information signal 14 OSD level information signal 15 Image correction level control signal 16 Image correction level control bus signal 17 Image output signal 18 IP conversion circuit 19 OSD mixing circuit 20 Black expansion circuit 21 Black detection circuit 22 Dark part gamma circuit 23 Dark part detection circuit 24 Light part gamma circuit 25 Light part detection circuit 26 Image quality circuit 27 Contrast circuit 28 Black level circuit 29 ABL circuit 30 Gamma circuit 31 Image luminance level detection circuit 32 Image luminance level detection signal 33 Image motion amount detection circuit 34 Image motion Amount detection signal 35 OSD information detection circuit 36 SD information detection signal 37 image correction level control circuit 40 first luminance level comparison circuit 41 the luminance level detection signal "1"
42 second brightness level comparison circuit 43 brightness level detection signal "2"
44 third luminance level comparison circuit 45 first OSD information comparison circuit 46 OSD information detection signal "1"
47 second OSD information comparison circuit 50 first control level determination circuit 51 control level determination signal "1"
52 Second control level determination circuit

Claims (4)

An image / OSD signal output from an image / OSD processing device in which an OSD signal is superimposed on an image signal is adjusted in image quality by the image processing device to obtain an image output signal in an OSD display receiver.
A dark part detection circuit for detecting a dark part area of the image / OSD signal;
A bright portion detection circuit for detecting a bright portion area of the image / OSD signal;
A first luminance level comparison circuit that compares a detection result of the dark part detection circuit with a detection result of the light part detection circuit;
A black detection circuit for detecting a black area of the image / OSD signal;
A second luminance level comparison circuit that compares a detection result of the black detection circuit with a comparison result of the first luminance level comparison circuit;
An ABL circuit that detects the brightness of the image output signal and controls a brightness level according to the brightness of the image output signal;
A third luminance level comparison circuit that compares a detection result of the ABL circuit with a comparison result of the second luminance level comparison circuit;
Have
An image correction level control bus signal to the image processing apparatus is changed by an image correction level control signal obtained by weighting and synthesizing a luminance level detection signal obtained by the third luminance level comparison circuit by an image correction level control circuit. An OSD display receiver for performing image quality correction according to a luminance level of the image / OSD signal. An image / OSD signal output from an image / OSD processing device in which an OSD signal is superimposed on an image signal is adjusted in image quality by the image processing device to obtain an image output signal in an OSD display receiver.
A first OSD information comparison circuit for comparing an OSD font information signal from the image / OSD processing device with an OSD area information signal from the image / OSD processing device;
A second OSD information comparison circuit that compares an OSD level information signal from the image / OSD processing device with a comparison result of the first OSD information comparison circuit;
Have
An image correction level control bus signal to the image processing apparatus is changed by an image correction level control signal obtained by weighting and combining an OSD information detection signal obtained by the second OSD information comparison circuit by an image correction level control circuit. And performing image quality correction according to the OSD magnitude and OSD luminance level of the image / OSD signal. An image / OSD signal output from an image / OSD processing device in which an OSD signal is superimposed on an image signal is adjusted in image quality by the image processing device to obtain an image output signal in an OSD display receiver.
A dark part detection circuit for detecting a dark area of the image / OSD signal;
A bright portion detection circuit for detecting a bright portion area of the image / OSD signal;
A first luminance level comparison circuit that compares a detection result of the dark part detection circuit with a detection result of the light part detection circuit;
A black detection circuit for detecting a black area of the image / OSD signal;
A second luminance level comparison circuit that compares a detection result of the black detection circuit with a comparison result of the first luminance level comparison circuit;
An ABL circuit that detects the brightness of the image output signal and controls a brightness level according to the brightness of the image output signal;
A third brightness level comparison circuit that compares a detection result of the ABL circuit with a comparison result of the second brightness level comparison circuit;
A first OSD information comparison circuit for comparing an OSD font information signal from the image / OSD processing device with an OSD area information signal from the image / OSD processing device;
A second OSD information comparison circuit that compares an OSD level information signal from the image / OSD processing device with a comparison result of the first OSD information comparison circuit;
Have
Image correction level control weighted and synthesized by an image correction level control circuit based on a luminance level detection signal obtained by the third luminance level comparison circuit and an OSD information detection signal obtained by the second OSD information comparison circuit An image correction level control bus signal to the image processing apparatus is changed by a signal to perform image quality correction in accordance with a luminance level, an OSD magnitude, and an OSD luminance level of the image / OSD signal. Display receiver. In claim 3,
A first control level determination circuit that compares the brightness level detection signal obtained by the third brightness level comparison circuit with the OSD information detection signal obtained by the second OSD information comparison circuit;
An image motion detection circuit that counts a motion amount detection signal obtained by an IP conversion circuit from the image / OSD processing device and determines a still image / moving image based on a certain threshold;
A second control level determination circuit that compares a determination result of the first control level determination circuit with a determination result of the image motion detection circuit;
Have
The image correction level control bus signal to the image processing apparatus is changed by the weighted and synthesized image correction level control signal obtained by the second control level determination circuit, so that the image brightness level of the image / OSD signal is changed. An OSD display receiver for performing image quality correction according to an OSD size, an OSD luminance level, and a motion amount.

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