JP2009206836A - System and method for adjusting color image quality - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a system for adjusting color image quality and its method capable of achieving conversion of independent color and independent color gamut without requiring complicated conversion of a color space. <P>SOLUTION: A system for adjusting color image quality includes converting color video signal sources into component video signals including a luminance signal and chrominance signals. A signal axis rotation circuit 31 performs coordination transformation on the chrominance signals in accordance with a hue calibration parameter. Then, a multiplier 32 multiplies the coordinate-transformed chrominance signals with a chroma calibration parameter to obtain output chrominance signals. The output chrominance signals and the luminance signal together form a component chromnance signal, which is processed and output by a chrominance signal inverse conversion unit. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to color image processing, and more particularly to a system and method for adjusting color image quality.

With the rapid development of video technology, more various video interface formats are being used. The most commonly used formats for color video signals include composite video signals, S-video signals, VGA-terminal RGB signals and component video signals.

The color data displayed by the color image is one of the main elements for displaying the image data. Basically, color data has three attributes: hue, luminance, and saturation. Hue indicates a color difference component. Luminance indicates the level of color brightness. Saturation indicates the purity of the color and is also referred to as chroma. A color video signal is composed of an R signal, a G signal, and a B signal and constitutes three primary colors. Encoding / decoding technology is used for transmission of a huge amount of data of color signals, and high image signal processing capability is required.

At the best known color difference video terminals currently employed in video / audio systems, the video signal is divided into three different component signals for signal transmission. These three component signals are a brightness or luminance signal Y and two chrominance signals Pb and Pr, respectively. The two chrominance signals Pb and Pr are composed of a blue signal and a red signal extracted from the three primary color signals.

Various techniques are used for processing image signals. One example is described in Taiwan Patent No. 200726272. This publication describes a method and apparatus for adjusting the color of a display device, and color video signals R, G, B from an image signal source are converted into a YUV image signal format by a color conversion circuit, and The YUV image signal is converted into the YCH image signal format by the hue conversion circuit. These generate an output image signal along with a hue difference lookup table, a saturation matching lookup table, an inverse hue transformation, and an inverse color transformation. The color image signal processing method disclosed as this known technique requires a complicated hardware circuit for color space conversion.

U.S. Patent No. 2004021671A1 discloses a color space conversion circuit that performs image signal processing for adjusting saturation, luminance, and hue. With this technique, the quality of the color image can be completely adjusted, but the circuit disclosed therein is basically implemented as hardware and therefore requires very complex circuit design.

US 2007086030 A1 discloses a conversion circuit and a conversion method for color image signals. This technique uses a processing circuit that performs complex matrix operations, and has a limited number of regions in which adjustment can be performed independently. Furthermore, it is generally impossible to calibrate the entire region by combining adjustments for brightness, saturation and hue.

As another example, US Pat. No. 6,552,751 shows a video signal processing circuit used to adjust the brightness, contrast and hue of a color video signal. The input video signal is first converted into a luminance signal and a chrominance signal by the first matrix circuit, and then processed by the processing performed by the signal processing circuit, and then converted by the second matrix circuit to obtain the image signal. Returned to This technique performs complex matrix operations and transformations.

As yet another example, U.S. Pat. No. 4,679,072 shows an image signal adjustment unit that realizes image signal adjustment by rotating coordinate axes. Although this technology uses a simple circuit architecture, the adjustment of the image quality of possible image signals is very limited and is therefore suitable for practical needs for modern video functions. I can not say.

Obviously, these conventional techniques have the following problems. This means that complex color space conversion is required, independent color and gamut conversion cannot be realized, complex mathematical operations are required, and a large memory space is required to store the lookup table. In order to combine the calibration of the entire area and the calibration of the individual areas, a complicated additional circuit is required.
Taiwan Patent No. 200726272 US Patent Publication No. 2004021671A1 US Patent Publication No. 2007086030A1 US Pat. No. 6,552,751 U.S. Pat. No. 4,679,072

Accordingly, it is an object of the present invention to provide a color image quality adjustment system and method in which a color video source signal is converted into a component video signal that includes an output luminance signal and an output chrominance signal.

Another object of the present invention is to provide a color image quality adjustment system and method capable of realizing independent color and color gamut conversion without requiring complex color space conversion.

To achieve the above object, in the solution according to the invention, the color video source signals R, G, B are converted by the color signal conversion unit into component video signals including luminance and chrominance signals, The component video signal is processed by a hue chroma conversion adjustment unit to perform coordinate conversion of the chrominance signal according to the hue calibration parameter. Then, according to the chroma calibration parameter, the multiplier performs a multiplication operation of the chrominance signal to generate an output chrominance signal.

In a preferred embodiment of the present invention, a hue calibration parameter and a chroma calibration parameter are generated by a calibration parameter generation unit based on a hue chroma mapping look-up table.

In a preferred embodiment of the present invention, there is further provided a luminance conversion adjustment unit, which receives the chrominance signal generated by the color signal conversion unit, and according to the luminance calibration parameter, by the adder. The received chrominance signal is added to generate an output luminance signal. The luminance conversion adjustment unit further includes an image / contrast adjustment unit, and this image / contrast adjustment adjusts the image contrast with respect to the output luminance signal generated by the luminance conversion adjustment unit.

Compared with the conventional color image processing technology, the present invention can realize independent color and color gamut conversion without complicated color space conversion. In the present invention, a superimposition of a plurality of mask lookup tables is used to generate a new mapping lookup table, which can be performed without requiring complicated mathematical operations. The memory space required for saving was reduced. Furthermore, the present invention collects and combines independent calibrations for all regions and individual regions without using an additional circuit, and enables calibration for individual regions with respect to luminance, chroma, and hue.

Hereinafter, a color image quality adjustment system according to a first embodiment of the present invention will be described with reference to FIG. This color image quality adjustment system is indicated by reference numeral 100 and comprises a color signal conversion unit 2, a hue chroma conversion adjustment unit 3, a chrominance signal inverse conversion unit 4, and a calibration parameter generation unit 5. The hue chroma conversion adjustment unit 3 includes a signal axis rotation circuit 31 and a multiplier 32.

First, the color video source signals R, G, B supplied from the image signal source are processed by the color signal conversion unit 2 and converted into color component video signals Y, Pb, Pr. The color component video signals Y, Pb and Pr are composed of a luminance signal Y and two chrominance signals Pb and Pr. The chrominance signals Pb and Pr are supplied to the hue chroma conversion adjustment unit 3, and coordinate conversion is performed according to the hue calibration parameter dH generated by the calibration parameter generation unit 5. Further, the multiplier 32 calculates a product of the chrominance signals Pb and Pr and the chroma calibration parameter dC generated by the calibration parameter generation unit 5 to generate output chrominance signals Pbo and Pro. .

By coordinate transformation performed by the signal axis rotation circuit 31, signal coordinate transformation of the chrominance signals Pb and Pr is executed according to the following formula based on the hue calibration parameter dH generated by the calibration parameter generation unit 5.

Here, Pb ′ and Pr ′ are coordinate-transformed chrominance signals, Pb and Pr are initially input chrominance signals, and dH_θ is an angle (θ) of the calibration parameter dH on the Pb-Pr coordinate plane. It is. The input chrominance signals Pb and Pr are converted into chrominance signals Pb ′ and Pr ′ subjected to coordinate conversion after being subjected to coordinate conversion executed by the signal axis rotation circuit 31 according to a coordinate conversion formula. The coordinate-converted chrominance signals Pb ′ and Pr ′ are supplied to the multiplier 32, and a product with the chroma calibration parameter dC generated by the calibration parameter generation unit 5 is obtained, and the output chrominance signal Pbo, Pro is obtained. The output chrominance signals Pbo and Pro are processed by the chrominance signal inverse conversion unit 4.

Simultaneously with the output chrominance signals Pbo and Pro, the luminance signal Y supplied from the color signal conversion unit 2 is also sent to the chrominance signal inverse conversion unit 4 and output as an output luminance signal Yo. The chrominance signal inverse conversion unit 4 outputs the output luminance signal Yo and the output chrominance signals Pbo, Pro to a target device (not shown).

The hue calibration parameter dH and the chroma calibration parameter dC are generated by the calibration parameter generation unit 5. The calibration parameter generation unit 5 executes a calculation using the video signals R, G, and B supplied from the image signal source 1 and generates a hue value Sh of the video signals R, G, and B. 51 is provided. Based on the hue values Sh of the video signals R, G, and B, the hue calibration parameter dH and the chroma calibration parameter dC are obtained together with the hue and chroma mapping look-up table 52.

FIG. 2 shows a flowchart for calculating the hue values of the video signals R, G and B by the hue calculation unit 51. First, the hue calculation unit 51 receives video signals R, G, and B from the image signal source 1 (step 101), and Vmax = max (R,
The maximum value of the video signals R, G, B indicated by (G, B) is specified (step 102), and the minimum value of the video signals R, G, B indicated by Vmin = min (R, G, B) Is identified (step 103). The difference between the maximum value and the minimum value of the video signals R, G, B indicated by ΔV = Vmax−Vmin is calculated (step 104).

Then, the maximum value and the minimum value are compared (step 105). If Vmax is equal to Vmin, the hue value Sh is set to zero (0) (step 106). If the comparison result at step 105 indicates that Vmax is not equal to Vmin, it is determined whether the video signal R is equal to Vmax (step 107). If the result of step 107 indicates that the video signal R is the same as Vmax, the hue value Sh is set as Sh = 60x (GB) / ΔV (step 108). If the result of step 107 indicates that the video signal R is not equal to Vmax, it is further determined whether the video signal G is equal to Vmax (step 109). If the result of step 109 indicates that the video signal G is the same as Vmax, the hue value Sh is set as Sh = 120 × (B−R) / ΔV (step 110). If the result of step 109 indicates that the video signal G is not the same as Vmax, the hue value Sh is set as Sh = 240 × (R−G) / ΔV (step 111).

After each of steps 108, 110, 111, it is further determined whether the calculated hue value Sh is less than zero (step 112). If the result is not less than zero, the hue value Sh calculated in these steps is directly output (step 113). Conversely, if the result is less than zero, 360 is added to the hue value (step 114). That is, Sh + 360 is calculated and output as an output hue value.

FIG. 3 is a block diagram showing a color image quality adjustment system according to the second embodiment of the present invention. This color image quality adjustment system is partially configured similarly to the color image quality adjustment system indicated by reference numeral 100 in FIG. 1, and corresponding elements / devices / parts are given the same reference numerals. Yes. A color image quality adjustment system according to the second embodiment is denoted by reference numeral 100a, and is a color signal conversion unit 2, a hue chroma conversion adjustment unit 3a, a chrominance signal inverse conversion unit 4, a calibration parameter generation unit 5a, and a luminance conversion adjustment. It consists of unit 6.

First, the color video source signals R, G, and B supplied from the image signal source are converted into color component video signals Y, Pb, and Pr. The color component video signals Y, Pb and Pr are composed of a luminance signal Y and two chrominance signals Pb and Pr. The chrominance signals Pb and Pr are supplied to the hue chroma conversion adjustment unit 3a, where they are subjected to coordinate conversion and multiplication, and output chrominance signals Pbo and Pro are generated.

The calibration parameter generation unit 5a includes a hue calculation unit 51 and a hue chroma luminance mapping lookup table 52a. Video signals R, G, B from the image signal source 1 are processed by the hue calculation unit 51 to obtain the hue values of the video signals R, G, B. Based on the hue value, a hue calibration parameter dH, a chroma calibration parameter dC, and a luminance calibration parameter dY are obtained by the hue chroma luminance mapping look-up table 52a.

Color video signals R, G, and B from the image signal source are converted into component video signals Y, Pb, and Pr. These component video signals Y, Pb, and Pr are converted into a luminance signal Y and a color signal conversion unit. 2 consists of two chrominance signals Pb and Pr processed by 2 and a luminance signal Y. Of these component video signals Y, Pb, and Pr, the chrominance signals Pb and Pr are processed by the hue chroma conversion adjustment unit 3a.

At the same time, the chrominance signals Pb and Pr are sent to the hue coefficient correction unit 33, and the product of the hue calibration parameter dH generated by the calibration parameter generation unit 5a is calculated by the multiplier 34, and the corrected hue is obtained. Calibration parameter dH1 is obtained. The corrected hue calibration parameter dH1 is then added to the entire area hue calibration parameter dH_All in the adder 35 to obtain a general hue parameter dH2. The all-region hue calibration parameter dH_All is defined as a parameter for simultaneous hue adjustment of all regions.

Further, the chroma calibration parameter dC generated by the calibration parameter generation unit 5a is multiplied by the all-region chroma calibration parameter dC_All to obtain a general chroma calibration parameter dC1. The all-region chroma calibration parameter dC_All is defined as a parameter for simultaneous chroma adjustment of all regions.

Further, the hue chroma conversion adjustment unit 3 a includes a signal axis rotation circuit 31. The signal axis rotation circuit 31 executes signal coordinate conversion based on the obtained general hue calibration parameter dH2. Thereafter, the product with the general chroma calibration parameter dC1 is executed by the multiplier 32 to obtain the output chrominance signals Pbo, Pro.

In this embodiment, the luminance conversion and adjustment unit 6 is used to process the luminance signal Y generated by the color signal conversion unit 2. First, the chrominance signals Pb and Pr are supplied to the luminance coefficient correction unit 61, and the product of the luminance calibration parameter dY generated by the calibration parameter generation unit 5a is calculated by the multiplier 62, and the corrected luminance calibration is performed. Parameter dY1 is obtained. Then, the entire luminance calibration parameter dY_All is added to the corrected luminance calibration parameter dY1 by the adder 63 to obtain a general luminance calibration parameter dY2. The whole area luminance calibration parameter dY_All is defined as a parameter for simultaneous luminance adjustment of all areas.

The luminance signal Y generated by the color signal conversion unit 2 is added with the whole region luminance calibration parameter dY2 by the adder 64, and the general luminance calibration parameter dY2 is obtained. The entire area luminance calibration parameter dY2 is output to the chrominance signal inverse conversion unit 4.

FIG. 4 is a block diagram showing a color image quality adjustment system according to the third embodiment of the present invention. This color image quality adjustment system is partially configured in the same manner as the color image quality adjustment system indicated by reference numeral 100a in FIG. 3, and corresponding elements / devices / parts are given the same reference numerals. Yes. A color image quality adjustment system according to the third embodiment is indicated by reference numeral 100b, and includes a color signal conversion unit 2, a hue chroma conversion adjustment unit 3a, a chrominance signal inverse conversion unit 4, a calibration parameter generation unit 5a, and a luminance. It consists of a conversion adjustment unit 6. These elements are connected in the same way as the corresponding elements of the embodiment shown in FIG. 3, and perform similar operations. 3 and 4, the difference between the two embodiments is that the luminance conversion adjustment unit 6 of the embodiment of FIG. 4 includes an image / contrast adjustment unit 7. After the luminance signal Y and the general luminance calibration parameter dY2 are added by the adder 64, the image / contrast adjustment unit 7 performs the adjustment of the contrast of the luminance signal Y, and the chrominance signal inverse conversion unit 4 The output luminance signal Yo to be output to is obtained.

In the above description of the preferred embodiment of the present invention, the color video source signals R, G, B generated based on the image signal source 1 consist of video signals R, G, B. The chrominance signal is composed of analog chrominance signals Pb and Pr or digital chrominance signals Cb and Cr, signals U and V, or signals I and Q.

The data of the chroma mapping look-up table 52 according to the first embodiment and the data of the hue chroma luminance mapping look-up table 52a according to the second embodiment are arranged in a mapping relationship. 5A and 5B are diagrams illustrating a mapping relationship between the hue value Sh and the hue calibration parameter dH. Here, the input value of the hue value Sh that is referred to as a calibration point and that the user wants to adjust or calibrate is shown on the horizontal axis, and is the amount calibrated and calibrated by the user. A hue calibration parameter dH indicating the magnitude of the hue calibration to be referred to is indicated on the vertical axis.

FIG. 5A shows the mask lookup table M_LUT. In this table M_LUT, the value of the hue calibration parameter dH includes the values [12, 11, 9, 6, 4, 2, 1]. The number and value of each entry included in the mask lookup table M_LUT can optionally be set by the user. Based on the chroma size (desired adjustment amount) that the user wishes to calibrate, the actual mask lookup table can be provided as follows.
Here, M_max = max (M_LUT), and M_max indicates the maximum value in the mask lookup table Real_M_LUT.

In the above example, the first entry in the mask lookup table M_LUT is the maximum value and is the point that the user wants to calibrate (calibration point) (as shown, where the hue value Sh With = 60). This calibration point is used as a mirror mapping center to obtain the same inverted part that is half of the mask lookup table. Both can be combined to form the real mask lookup table Real_M_LUT. Use as mirror mapping center to get the same inverted part that is half of the mask lookup table, and finally superimpose many real mask lookup tables Real_M_LUT A simple lookup table Final_LUT. Then, as shown in FIG. 5B, it is a superposition of n actual mask lookup tables Real_M_LUT.

6A and 6B superimpose the three real mask lookup tables Real_M_LUT to form one final profile of the output. In this embodiment, the calibration point of the hue value Sh that the user wishes to adjust is [60, 65, 70]. The desired adjusted hue amounts are [10, 8, 10], respectively. The result of the superposition of the three real mask lookup tables, denoted as M11, M12 and M13, respectively, is illustrated in FIG. 6B. The number of actual mask lookup tables to be superimposed is not particularly limited, and usually varies depending on the calibration range for each region. The user can change the calibration point and the desired calibrated profile resulting from the superposition of the calibration amounts.

7A and 7B are diagrams showing other profiles obtained from superimposing three real mask look-up tables. In this example, the calibration points for the calibration of the hue value Sh are [60, 65, 70]. The desired calibration values are [8, 10, 8], respectively. The result of superposition of the three real mask lookup tables, denoted as M21, M22 and M23, respectively, is illustrated in FIG. 7B.

8A and 8B show the mapping relationship between the hue value Sh and the chroma calibration parameter dC. Here, the input value of the hue value Sh that is referred to as a calibration point and that the user wants to adjust or calibrate is shown on the horizontal axis, and is the amount calibrated and calibrated by the user. The hue calibration parameter dC indicating the magnitude of the referred saturation calibration is indicated on the vertical axis.

FIG. 8A shows a mask lookup table M_LUT that includes a number of entries having a value of [12, 11, 9, 4, 2, 1] as the chroma calibration parameter dC. The number and values of entries contained in the mask lookup table M_LUT can be arbitrarily set by the user.
Here, M_max = max (M_LUT), and M_max indicates the maximum value in the mask lookup table Real_M_LUT.

In the above example, the first entry in the mask lookup table M_LUT is the maximum value and is the point that the user wants to calibrate (calibration point) (as shown, where the hue value Sh With = 60). This calibration point is used as a mirror mapping center for obtaining the same target portion of the mask lookup table M_LUT. Both can be combined to form the real mask lookup table Real_M_LUT. Finally, a number of real mask lookup tables Real_M_LUT are superimposed to form the final lookup table Final_LUT. Then, as shown in FIG. 8B, 1+ (n real mask look-up tables Real_M_LUT are superimposed).

9 to 12 show the calibration of hue and luminance performed by the hue coefficient correction unit 33 (also corresponding to the luminance coefficient correction unit 6) shown in FIG. 3 for different individual regions. It is a figure which shows a magnitude | size. As shown here, for the hue and brightness of each region, the magnitude of calibration is corrected according to the following chroma data.

(1) Coef_Y_y and Coef_H_y are correction values for coefficients of Y (luminance) and H (hue) on the vertical axis, respectively, and have values between 0 and 1.

(2) The correction value of the coefficient on the horizontal axis is Coef_x = (PbxPb + PrxPr) ^ 0.5. Coefficient input is determined at set points P1 to Pn according to Coef_x. Here, n indicates the number of set points. In the drawing, the number of set points (n) is at least 3, and no upper limit is defined for the maximum number.

(3) Other embodiments

(3-1) As shown in FIG. 9, the hue and luminance calibration amounts used for adjustment in individual regions do not change with the desired calibration amount used for adjustment in another chrominance.

(3-2) Hue and brightness calibration used for adjustment in each region only affects medium or high chrominance. In this embodiment, at a low chrominance, the correction value of the output coefficient is Coef_out = 0, and accordingly, the hue and luminance magnitudes adjusted in individual regions are 0 as shown in FIG.

(3-3) Hue and brightness calibration used for adjustment in individual areas only affects medium or low chrominance. In this embodiment, the correction value of the output coefficient is Coef_out = 0 at high chrominance. Therefore, the hue and brightness adjusted in each region are 0 as shown in FIG.

(3-4) As shown in FIG. 12, the hue and luminance calibration amounts obtained by adjusting the individual regions in accordance with the request for calibration take different values at different chrominance positions.

13 and 14 are diagrams showing that the relationship between the input luminance signal Y1 and the output luminance signal Y0 generated by the image / contrast adjustment unit 7 of FIG. 4 is an S-shaped curve, which is darker. Make areas darker and lighter areas brighter. This S-shaped curve is obtained by using an arithmetic method and can be constituted by a plurality of points, for example, four points. (255, 255), (x1, y1), (x2,
For example, if it is composed of four points (y2) and (0, 0), the contrast level of the image is adjusted by changing the coordinates of the two middle points (x1, y1) and (x2, y2). can do.

The present invention has been described with reference to the embodiments. However, the present invention can be variously modified and changed by those skilled in the art without departing from the spirit of the present invention described in the appended claims. Should be understood.

1 is a block diagram illustrating a color image quality adjustment system according to a first embodiment of the present invention. 2 shows a flowchart for calculating the hue values of video signals R, G, B by the hue calculation unit shown in FIG. 6 is a block diagram illustrating a color image quality adjustment system according to a second embodiment of the present invention. 7 is a block diagram illustrating a color image quality adjustment system according to a third embodiment of the present invention. It is a figure which shows the mapping relationship between the hue value Sh and the hue calibration parameter dH. It is a figure which shows the mapping relationship between the hue value Sh and the hue calibration parameter dH. FIG. 6 shows one final profile of the output formed by superimposing three real mask look-up tables. FIG. 6 shows one final profile of the output formed by superimposing three real mask look-up tables. FIG. 10 is a diagram showing another profile obtained by superimposing three real mask lookup tables. FIG. 10 is a diagram showing another profile obtained by superimposing three real mask lookup tables. The mapping relationship between the hue value Sh and the chroma calibration parameter dC is shown. The mapping relationship between the hue value Sh and the chroma calibration parameter dC is shown. FIG. 4 is a diagram showing the magnitude of calibration for hue and luminance executed by the hue coefficient correction unit or the luminance coefficient correction unit shown in FIG. 3 for different individual areas. FIG. 4 is a diagram showing the magnitude of calibration for hue and luminance executed by the hue coefficient correction unit or the luminance coefficient correction unit shown in FIG. 3 for different individual areas. FIG. 4 is a diagram showing the magnitude of calibration for hue and luminance executed by the hue coefficient correction unit or the luminance coefficient correction unit shown in FIG. 3 for different individual areas. FIG. 4 is a diagram showing the magnitude of calibration for hue and luminance executed by the hue coefficient correction unit or the luminance coefficient correction unit shown in FIG. 3 for different individual areas. It is a figure which shows that the relationship between the input luminance signal produced | generated by the image contrast control unit of FIG. 4 and an output luminance signal is a S-shaped curve. It is a figure which shows that the relationship between the input luminance signal produced | generated by the image contrast control unit of FIG. 4 and an output luminance signal is a S-shaped curve.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image signal source 2 Color signal conversion unit 3 Hue chroma conversion adjustment unit 3a Hue chroma conversion adjustment unit 4 Chrominance signal reverse conversion unit 5 Parameter generation unit 5a Parameter generation unit 6 Brightness conversion adjustment unit 7 Contrast adjustment unit 31 Signal axis rotation circuit 32 Multiplier 33 Hue coefficient correction unit 34 Multiplier 35 Adder 51 Hue calculation unit 52 Chroma mapping look-up table 52a Hue chroma luminance mapping look-up table 61 Luminance coefficient correction unit 62 Multiplier 63 Adder 64 Adder

Claims (20)

A color signal conversion unit for inputting a color video source signal and converting the color video source signal into a component video signal composed of a luminance signal and a chrominance signal;
Perform a color video source signal calculation process to obtain the hue value of the color video source signal, and based on this hue value, at least one hue calibration parameter and at least one chroma calibration Calibration parameter generation unit for obtaining calibration parameters according to a hue chroma mapping lookup table;
The chrominance signal generated by the color signal conversion unit is received, coordinate conversion of the chrominance signal is performed according to the hue calibration parameter, multiplication operation of the chrominance signal is performed according to the chroma calibration parameter, and output chrominance is performed. A color image quality adjustment system comprising a hue chroma conversion adjustment unit that generates a signal. The color video source is a color video source signal R, G, B, and the chrominance signal is an analog chrominance signal Pb, Pr or a digital chrominance signal Cb, Cr, a signal U, V, I, The color image quality adjusting system according to claim 1, wherein the color image quality adjusting system is Q. The hue chroma conversion adjustment unit receives a chrominance signal, performs coordinate conversion of the chrominance signal based on a hue calibration parameter, and generates a chrominance signal subjected to coordinate conversion, and the coordinate The color image quality of claim 1, further comprising a multiplier that calculates a product of the converted chrominance signal and the chroma calibration parameter to generate an output chrominance signal. Adjustment system. The luminance signal generated by the color signal conversion unit and the output chrominance signal generated by the hue chroma conversion adjustment unit form a component chrominance signal output through the chrominance signal inverse conversion unit. The color image quality adjustment system according to claim 1. A color signal conversion unit for inputting a color video source signal and converting the color video source signal into a component video signal composed of a luminance signal and a chrominance signal;
Perform a color video source signal calculation process to obtain the hue value of the color video source signal, and based on this hue value, at least one hue calibration parameter and at least one chroma calibration A calibration parameter generation unit for obtaining a calibration parameter and at least one luminance calibration parameter according to a hue chroma luminance mapping mapping lookup table;
The chrominance signal generated by the color signal conversion unit is received, coordinate conversion of the chrominance signal is performed according to the hue calibration parameter, signal multiplication operation of the chrominance signal is performed according to the chroma calibration parameter, and output. A hue chroma conversion adjustment unit that generates a chrominance signal, and the chrominance signal generated by the color signal conversion unit are received, and the adder adds the chrominance signal according to a luminance calibration parameter, and outputs an output luminance signal. A luminance conversion adjustment unit for generating a color image quality adjustment system. The color video source is a color video source signal R, G, B, and the chrominance signal is an analog chrominance signal Pb, Pr or a digital chrominance signal Cb, Cr, a signal U, V, I, The color image quality adjustment system according to claim 5, wherein the color image quality adjustment system is Q. The hue chroma conversion adjustment unit receives a chrominance signal, performs coordinate conversion of the chrominance signal based on a hue calibration parameter, and generates a chrominance signal subjected to coordinate conversion, and the coordinate 6. The color image quality according to claim 5, further comprising a multiplier that calculates a product of the converted chrominance signal and the chroma calibration parameter to generate an output chrominance signal. Adjustment system. The output luminance signal generated by the luminance conversion adjustment unit and the output chrominance signal generated by the hue chroma conversion adjustment unit form a component chrominance signal output via the chrominance signal inverse conversion unit. The color image quality adjustment system according to claim 5. The chrominance signal is supplied to a hue coefficient correction unit, and the product of the hue calibration parameter generated by the calibration parameter generation unit is calculated by a multiplier to obtain a corrected hue calibration parameter. The hue calibration parameter is added to the whole area hue calibration parameter by the adder to obtain a general hue parameter, which is output to the hue chroma conversion adjustment unit, and the hue chroma conversion adjustment is performed. 6. The color image quality adjustment system according to claim 5, wherein the color image quality adjustment system functions as a hue calibration parameter for coordinate conversion performed by the unit. The chroma calibration parameter generated by the calibration parameter generation unit is multiplied by the entire area chroma calibration parameter by a multiplier to obtain a general chroma calibration parameter. The dynamic chroma calibration parameter is output to a multiplier of the hue chroma conversion adjustment unit, and is used as a chroma calibration parameter for a signal multiplication operation performed by the hue chroma conversion adjustment unit. The color image quality adjustment system according to claim 5. The luminance conversion adjustment unit comprises a luminance coefficient correction unit, which receives the chrominance signal generated by the color signal conversion unit, performs the luminance coefficient correction of the chrominance signal, and is calibrated by a multiplier. The product of the brightness calibration parameter generated from the calibration parameter generation unit is calculated to obtain a corrected brightness calibration parameter. The corrected brightness calibration parameter is added to the whole area brightness calibration by an adder. A parameter is added to obtain a general brightness calibration parameter, which is used as a brightness calibration parameter for the brightness conversion adjustment unit to generate an output brightness signal. Characterized in that it is needed, the color image quality adjusting system according to claim 5. The luminance conversion adjustment unit includes an image / contrast adjustment unit. The image / contrast adjustment is performed on the output luminance signal before the output luminance signal generated by the luminance conversion adjustment unit is output. The color image quality adjustment system according to claim 11, wherein contrast is adjusted. (a) inputting a color video source signal and converting the color video source signal into a component chrominance signal comprising a luminance signal and a chrominance signal;
(b) performing a calculation process of the input color video source signal to obtain a hue value of the color video source signal;
(c) obtaining at least one hue calibration parameter and at least one chroma calibration parameter according to the hue chroma mapping lookup table based on the calculated hue value;
(d) performing coordinate transformation of signal axis rotation on the chrominance signal according to a predetermined coordinate transformation formula based on the hue calibration parameter;
(e) A color image quality adjustment method comprising: performing signal multiplication of a chroma calibration parameter on the converted chrominance signal to obtain an output chrominance signal. In step (a), the color video source is a color video source signal R, G, B, and the chrominance signal is an analog chrominance signal Pb, Pr or a digital chrominance signal Cb, Cr, 14. The color image quality adjusting method according to claim 13, comprising signals U, V, I, and Q. The predetermined coordinate conversion formula is:
Where Pb ′ and Pr ′ are coordinate-transformed chrominance signals, Pb and Pr are initially input chrominance signals, and dH_θ is the angle θ of the calibration parameter dH on the Pb-Pr coordinate plane The color image quality adjustment method according to claim 13, wherein: In step (b), the hue value of the color video source signal is:
(b1) identifying the maximum and minimum values of the color video source signal and determining a difference ΔV between the maximum and minimum values;
(b2) comparing the maximum value and the minimum value to determine whether the maximum value and the minimum value are the same, and if so, generating 0 as the hue value;
(b3) If the maximum value and the minimum value are not the same, it is further determined whether or not the R video signal is equal to the maximum value, and if they are equal, a hue value of 60 × (GB) / ΔV is generated and is not equal. If it is, it is further determined whether the G video signal is equal to the maximum value, if it is equal, 120 × (BR) / ΔV is generated as the hue value, otherwise 240 × (RG) is determined as the hue value. The color image quality adjustment method according to claim 13, wherein the color image quality adjustment method is acquired from the step of generating / ΔV. After the step (b3), (b4) determine whether the hue value is less than zero, and if not less than zero, output the hue value as it is, and if less than zero, add 360 to the hue value. The color image quality adjustment method according to claim 16, further comprising the step of adding the values to obtain a new hue value. The step (f) further comprises a step of obtaining a luminance calibration parameter by referring to a hue chroma luminance mapping lookup table based on the calculated hue value. Item 14. The color image quality adjustment method according to Item 13. 19. The color image quality adjustment method according to claim 18, further comprising a step of adding the chrominance signal by an adder according to the luminance calibration parameter to generate an output luminance signal. The hue chroma mapping lookup table is
(a) defining a mask lookup table M_LUT for this hue chroma mapping lookup table;
(b) The maximum value of the mask lookup table M_LUT is M_max = max (M_LUT), and the actual mask lookup table is based on the hue calibration point set by the user and the desired hue calibration amount. Calculating Real_M_LUT by Real_M_LUT = M_LUTx (desired hue calibration amount / M_max);
(c) Set the first entry of the mask lookup table M_LUT to the maximum value corresponding to the hue calibration point set by the user, and the same inverted part that is half of the mask lookup table Using as a mirror mapping center to obtain
(d) superposing a number of real mask look-up tables Real_M_LUT to form a final look-up table and using it as a hue chroma mapping look-up table, The color image quality adjustment method according to claim 18.