CN101325723B - System and method for adjusting image color - Google Patents

Abstract

This invention discloses an adjusting method of image color, comprising a saturation calculator that receives a RGB pixel and generates a saturation of the pixel; a color calculator that receives the RGB pixel; a first device of table search storing with multiple first adjusting coefficient pair outputs the first adjusting coefficient pair based on the color of the pixel; a second device of tablesearch storing with multiple second adjusting coefficient pair outputs the second coefficient pair based on the color of the pixel. The system further comprises a mixing device which executes weighting calculation to the first and second adjusting coefficients based on the saturation of the pixel so as to generate an output coefficient pair, a Uv converter that adjusts the U value and V value of the pixel based on output coefficient pair.

Description

A kind of image color Adjustment System and method

Technical field

The present invention relates to the image color processing technology field, particularly a kind of image color Adjustment System and method.

Background technology

Because digital camera, Video Camera, display, color printer, LCD television set still continue significantly to grow up in the world market, and product reaches its maturity, thereby Related product also then the lifting of pursuit quality.Colour technology has decisive influence to the quality and the effect of image system product, user's buying behavior be subjected to color video quality and the influence of the chromatic image processing capacity that provided very big.

In the image multimedia equipment, the user wishes that the image color of seeing is correct usually, so no matter be to input or output device, all need and correct color rendition can be seen just what what just obtains.But, after obtaining correct color, the user is not content with this toward contact, because different color group credit unions brings people different impressions in the identical image, more meet the color representation of self liking so the user wishes to have, this just likes the notion of look (Favorite Color), and the hobby look has been given the ability of user's adjusting device color representation, make that device for image can be with the color rendition of user hobby, such as effect such as sky is more blue, the meadow is greener.

Yet existing image color treatment technology can't be done different form and aspect or chroma adjustment according to different colors when adjusting form and aspect and chroma.At the problems referred to above, the phase information that U.S. Patent application disclose in early days No. 20060087591 foundation is different is adjusted in-phase signal I (in-phase signal) and phase signals Q (quadrature signal) just, as shown in Figure 1, comprise a phase difference device 102, delay release 106, a color table 104, a whirligig 110, a gain apparatus 112 and a saturation table 108.The input signal of phase difference device 102 is the I component and the Q component of a chroma signals (chrominance), and phase difference device 102 is calculated a phase place according to I component and Q component, and exports color table 104 to.Color table 104 is tabled look-up according to this phase place and is obtained an anglec of rotation.Whirligig 110 receives this anglec of rotation, calculates corresponding cos () and sin () value, and according to cos () that is calculated and sin () value I and Q component is carried out twiddle operation, and then adjusts the colourity and the saturation of this chroma signals (chrominance).

Fig. 2 is the structural representation of existing whirligig.As shown in Figure 2, whirligig 110 not only need have the computing engines of cos (), sin (), also needs a gyrator device simultaneously, is used for I and Q component are carried out twiddle operation and obtain I ' and Q ' component.Yet in side circuit, the computing engines of cos (), sin () not only expends many gates, also wastes a large amount of energy simultaneously.And can't adjust its carrier chrominance signal respectively at the different colours scope.Hence one can see that, and conventional images color Adjustment System and method still have the space of improvement.

Summary of the invention

A main purpose of the present invention is to provide a kind of image color Adjustment System, adjusts its carrier chrominance signal respectively at the different colours scope, thereby better ease of use is provided.

Another object of the present invention is to provide a kind of image color method of adjustment, adjust its carrier chrominance signal respectively, avoid using the computing engines of cos (), sin () simultaneously, thereby reduce cost and the expending of the energy at the different colours scope.

According to a main purpose of the present invention, the present invention proposes a kind of image color Adjustment System, comprises a saturation computation device, a colourity calculation element, one first table look-up device, one second table look-up device and a mixing apparatus.Described saturation computation device receives a rgb pixel, and produces a saturation of this pixel; Described colourity calculation element receives described rgb pixel, and produces a colourity of described pixel; Described first table look-up device is connected to described colourity calculation element, it is right that described first table look-up device stores a plurality of first adjustment coefficients, it is right to export one first corresponding adjustment coefficient according to the colourity of described pixel, and this first adjustment coefficient is to presetting the saturation and the first default colourity generation according to first; Described second table look-up device is connected to described colourity calculation element, it is right that described second table look-up device stores a plurality of second adjustment coefficients, it is right to export one second corresponding adjustment coefficient according to the colourity of described pixel, and this second adjustment coefficient is to presetting the saturation and the second default colourity generation according to second; Described mixing apparatus is connected to described saturation computation device, described first table look-up device and described second table look-up device, adjust coefficient according to the saturation of described pixel to described first and adjust coefficient to carrying out ranking operation to reaching described second, it is right to produce an output factor.

According to another object of the present invention, the present invention proposes a kind of image color method of adjustment, comprises the following step: a saturation computation step receives a rgb pixel, and produces a saturation of described rgb pixel; One colourity calculation procedure receives described rgb pixel, and produces a colourity of described rgb pixel; One first step of tabling look-up, according to the colourity of described rgb pixel one first table look-up device is carried out table lookup operation, it is right that one first of output correspondence is adjusted coefficient, this first adjustment coefficient is to producing according to the first default saturation and the first default colourity, wherein, it is right that described first table look-up device stores a plurality of described first adjustment coefficients; One second step of tabling look-up, according to the colourity of described rgb pixel one second table look-up device is carried out table lookup operation, it is right that one second of output correspondence is adjusted coefficient, this second adjustment coefficient is to producing according to the second default saturation and the second default colourity, wherein, it is right that described second table look-up device stores a plurality of described second adjustment coefficients; One mixed step is adjusted coefficient according to the saturation of described rgb pixel to described first and is adjusted coefficient to carrying out ranking operation to reaching described second, and it is right to produce an output factor.

Description of drawings

Fig. 1 is the prior art constructions schematic diagram;

Fig. 2 is the structural representation of existing whirligig;

Fig. 3 is the structural representation of image color Adjustment System one embodiment of the present invention;

Fig. 4 is the schematic diagram of the present invention's first table look-up device stored contents;

Fig. 5 is the structural representation of another embodiment of image color Adjustment System of the present invention.

Label declaration in the accompanying drawing:

Phase difference device 102 delay releases 106

Color table 104 whirligigs 110

Gain apparatus 112 saturation table 108

YUV to RGB conversion equipment 310

Saturation computation device 320

Colourity calculation element 330

First table look-up device 340

Second table look-up device 350

Mixing apparatus 360

UV conversion equipment 370

First table look-up device 610

Second table look-up device 620

Controller 630

Input unit 640

Embodiment

Fig. 3 is the structural representation of image color Adjustment System one embodiment of the present invention, and this image color Adjustment System comprises a saturation computation device 320, a colourity calculation element 330, one first table look-up device 340, one second table look-up device 350, a mixing apparatus 360, YUV to a RGB conversion equipment 310 and a UV conversion equipment 370.

YUV to RGB conversion equipment 310, the pixel transitions that is used for a yuv format is the pixel of a rgb format.YUV to RGB conversion equipment 310 can go to RGB with YUV according to following formula:

R＝Y+1.371×V

G＝Y-0.336U-0.698V

B＝Y+1.732U

Wherein, YUV to RGB conversion equipment 310 can be realized by hardware description language (Hardware DescriptionLanguage).

Saturation computation device 320 receives this rgb pixel, and produces a saturation of this pixel.The saturation Sat calculating formula of this rgb pixel can be: and fix{[1-3*min (R, G, B)/(R+G+B)] * 255}, and wherein, R, G, B are respectively red value, green value and the blue valve of this pixel, and min () is a minimum function, and fix is the ceiling function.Wherein, 0≤Sat≤255.That is to say that in the present embodiment, this saturation Sat uses 8 records, among other embodiment, according to the needs in the design, this saturation Sat also can use other record, to increase accuracy.

Colourity calculation element 330 receives this rgb pixel, and produces a colourity Hue of this rgb pixel.The colourity Hue calculating formula of this rgb pixel can be:

$\mathrm{Hue}=\left\{\begin{array}{cc}\mathrm{\θ},& B\≤G\\ 360-\mathrm{\θ},& B>G\end{array}\right.$

Wherein, $\mathrm{\θ}={\cos }^{-1}\{0.5*[(R-G)+(R-B)]/{[{(R-G)}^2+(R-B)(G-B)]}^{\frac{1}{2}}\},$ R, G, B are respectively red value, green value and the blue valve of this rgb pixel.The size of colourity Hue is between 0 and 359, that is 0≤Hue≤359.

First table look-up device 340 is connected to colourity calculation element 330.First table look-up device 340 stores a plurality of first, and to adjust coefficients right, according to the colourity Hue output of this rgb pixel corresponding one first adjust coefficient to table1_value.This first adjustment coefficient produces according to one first default saturation and one first default colourity table1_value.

Fig. 4 is the schematic diagram of the present invention's first table look-up device 340 stored contents.As shown in Figure 4, when colourity Hue was first scope (0 °～59 °) and the 3rd scope (120 °～359 °), first to adjust coefficient be (1,0) to table1_value for this, that is output equals to import, and do not adjust.When colourity Hue was second scope (60 °～119 °), this first adjustment coefficient was preset saturation Sat to table1_value according to first _Deft1Reaching the first default colourity produces.In the present embodiment, the first default colourity is 10 °, that is this first adjustment coefficient is (Sat to table1_value _Delt1* Cos (10 °), Sat _Deft1* Sin (10 °))., look for corresponding first at first table look-up device 340 and adjust coefficient as index (index) according to colourity Hue table1_value and output.

It is right that second table look-up device 350 is connected to a plurality of second adjustment coefficients of colourity calculation element 330, the second table look-up devices 350 storages, exports one second corresponding adjustment coefficient to table2_value according to the colourity of this pixel.This second adjustment coefficient produces according to one second default saturation and one second default colourity table2_value.

When colourity Hue was the 4th scope (0 °～119 °) and the 6th scope (240 °～359 °), this second adjustment coefficient was (1,0) to table2_value, i.e. output equals input, does not adjust.When colourity Hue was the 5th scope (120 °～239 °), this second adjustment coefficient was preset saturation Sat to table2_value according to second _Deft2Reaching the second default colourity produces.In the present embodiment, the second default colourity is 10 °, and promptly this second adjustment coefficient is (Sat to table2_value _Delt2* Cos (10 °), Sat _Deft2* Sin (10 °)).

The stored contents of the stored contents of second table look-up device 350 and Fig. 4 first table look-up device 340 is similar, for those skilled in the art can finish easily, will not give unnecessary details.Yet, it is emphasized that the above-mentioned first default saturation Sat _Deft1, the first default colourity, the second default saturation Sat _Deft2, the second default colourity, first scope, second scope, the 3rd scope, the 4th scope, the 5th scope and the 6th scope only be for convenience of description, those skilled in the art can adjust according to the technology of the present invention.

Mixing apparatus 360 is connected to saturation computation device 320, first table look-up device 340 and second table look-up device 350, saturation Sat according to this pixel carries out ranking operation to table1_value and this second adjustment coefficient to table2_value to this first adjustment coefficient, and it is right to produce an output factor.

When the saturation Sat of this rgb pixel preset saturation less than one the 3rd, the output factor of mixing apparatus 360 was right to being this first adjustment coefficient.When the saturation Sat of this pixel preset saturation greater than one the 4th, this output factor was right to being this second adjustment coefficient.When the saturation Sat of this pixel preset saturation greater than the saturation of the 3rd default saturation and this pixel less than the 4th, this output factor was to being:

α×table1_value+(1-α)×table2_value，

Wherein, table1_value is that the first adjustment coefficient is right, and table2_value is that the second adjustment coefficient is right, 0≤α≤1.

UV conversion equipment 370 is connected to mixing apparatus 360, is used for according to U value and the V value of this output factor to adjusting this YUV pixel.UV conversion equipment 370 is adjusted the U value and the V value of this YUV pixel according to following formula:

$\left[\begin{array}{c}\mathrm{Uout}\\ \mathrm{Vout}\end{array}\right]=\left[\begin{array}{cc}a1& a2\\ -a2& a1\end{array}\right]\left[\begin{array}{c}U\\ V\end{array}\right],$

Wherein, a1 and a2 are the coefficient of this output factor, and U and V are respectively the U value and the V value of this YUV pixel.

Fig. 5 is the structural representation of another embodiment of image color Adjustment System of the present invention.As shown in Figure 5, be a newly-increased controller 630 and an input unit 640 with the main difference of Fig. 3, and change first table look-up device 610 and second table look-up device 620 into an erasable storage device.First table look-up device 610 and second table look-up device 620 can be flash memory, static random access device (SRAM) or dynamic randon access device (DRAM).

When the user selectes this first default saturation Sat through input unit 640 _Deft1, the first default colourity, the second default saturation Sat _Deft2, during relevant parameter such as the second default colourity, first scope, second scope, the 3rd scope, the 4th scope, the 5th scope and the 6th scope, calculation of parameter first table look-up device 610 that controller 630 is selected according to the user and the corresponding content of second table look-up device 620, and write in first table look-up device 610 and second table look-up device 620.

As shown in the above description, the present invention utilizes saturation computation device 320, colourity calculation element 330, first table look-up device 340, second table look-up device 350 and mixing apparatus 360, adjust its carrier chrominance signal (U respectively at the different colours scope, V signal), thus reach the purpose that color is adjusted.Simultaneously, define the color of each picture element, utilize first table look-up device and second table look-up device again, can adjust its carrier chrominance signal respectively at the different colours scope, thereby access the color (favorite color) that meets hobby by form and aspect that calculate and chroma.The present invention removes according to different picture element hue value and sets different form and aspect and chroma change amount, can also set different form and aspect and chroma change amount according to different pixel saturation values, that is simultaneously according to hue value and the chroma value decision form and aspect and the chroma change amount of picture element, thereby can more accurate adjustment want the color gamut adjusted.

The foregoing description only be for convenience of description and for embodiment, the interest field that the present invention advocated should be as the criterion so that the patent application scope is described, but not only limits to the foregoing description.

Claims (20)

1. an image color Adjustment System is characterized in that, comprises:

One saturation computation device receives a rgb pixel, and produces a saturation of described rgb pixel;

One colourity calculation element receives described rgb pixel, and produces a colourity of described rgb pixel;

One first table look-up device, be connected to described colourity calculation element, it is right to be used for according to one first corresponding adjustment coefficient of the colourity output of described pixel, this first adjustment coefficient is to producing according to the first default saturation and the first default colourity, wherein, it is right that described first table look-up device stores a plurality of described first adjustment coefficients;

One second table look-up device, be connected to described colourity calculation element, it is right to be used for according to one second corresponding adjustment coefficient of the colourity output of described pixel, this second adjustment coefficient is to producing according to the second default saturation and the second default colourity, wherein, it is right that described second table look-up device stores a plurality of described second adjustment coefficients; And

One mixing apparatus, connect described saturation computation device, described first table look-up device and described second table look-up device respectively, according to the saturation of described rgb pixel, adjust coefficient to described first and adjust coefficient to carrying out ranking operation reaching described second, it is right to produce an output factor.

2. image color Adjustment System as claimed in claim 1 is characterized in that, further comprises:

One YUV to RGB conversion equipment, being used for a YUV pixel transitions is that described rgb pixel also sends to described saturation computation device and described colourity calculation element respectively.

3. image color Adjustment System as claimed in claim 2 is characterized in that, further comprises:

One UV conversion equipment connects described mixing apparatus, is used for according to U value and the V value of described output factor to adjusting described YUV pixel.

4. image color Adjustment System as claimed in claim 1 is characterized in that, the saturation of described rgb pixel is:

Sat＝fix{[1-3*min(R，G，B)/(R+G+B)]*255}，

Wherein, R, G, B are respectively red value, green value and the blue valve of described pixel, and min () is a minimum function, and fix is the ceiling function, and Sat is the saturation of described rgb pixel.

5. image color Adjustment System as claimed in claim 1 is characterized in that, the colourity of described rgb pixel is:

$\mathrm{Hue}=\left\{\begin{array}{cc}\mathrm{\θ},& B\≤G\\ 360-\mathrm{\θ},& B>G,\end{array}\right.$

Wherein, $\mathrm{\θ}={\cos }^{-1}\{0.5*[(R-G)+(R-B)]/{[{(R-G)}^2+(R-B)(G-B)]}^{\frac{1}{2}}\},$ R, G, B are respectively red value, green value and the blue valve of described pixel, and Hue is the colourity of described rgb pixel.

6. image color Adjustment System as claimed in claim 1 is characterized in that, described first table look-up device is erasable storage device.

7. image color Adjustment System as claimed in claim 1 is characterized in that, described second table look-up device is erasable storage device.

8. image color Adjustment System as claimed in claim 3 is characterized in that, and is when the saturation of described pixel is preset saturation less than one the 3rd, that described output factor is right to being set at the described first adjustment coefficient.

9. image color Adjustment System as claimed in claim 8, it is characterized in that, when the saturation of described pixel was preset saturation greater than one the 4th, described output factor is right to being set at the described second adjustment coefficient, and the described the 3rd default saturation was less than the described the 4th default saturation.

10. image color Adjustment System as claimed in claim 9 is characterized in that, when the saturation of described rgb pixel is preset saturation greater than the saturation of the described the 3rd default saturation and described rgb pixel less than the described the 4th, described output factor is set at:

α×table1_value+(1-α)×table2_value，

Wherein, table1_value is that the described first adjustment coefficient is right, and table2_value is that the described second adjustment coefficient is right, 0≤α≤1.

11. an image color method of adjustment is characterized in that, comprises the following step:

One saturation computation step receives a rgb pixel, and produces a saturation of described rgb pixel;

One colourity calculation procedure receives this rgb pixel, and produces a colourity of described rgb pixel;

One first step of tabling look-up, colourity according to described pixel is carried out table lookup operation to one first table look-up device, it is right that one first of output correspondence is adjusted coefficient, this first adjustment coefficient is to producing according to the first default saturation and the first default colourity, wherein, it is right that described first table look-up device stores a plurality of described first adjustment coefficients;

One second step of tabling look-up, colourity according to described rgb pixel is carried out table lookup operation to one second table look-up device, it is right that one second of output correspondence is adjusted coefficient, this second adjustment coefficient is to producing according to the second default saturation and the second default colourity, wherein, it is right that described second table look-up device stores a plurality of described second adjustment coefficients; And

One mixed step according to the saturation of described rgb pixel, is adjusted coefficient to described first and adjusted coefficient to carrying out ranking operation to reaching described second, and is right to produce an output factor.

12. image color method of adjustment as claimed in claim 11 is characterized in that, taking a step forward in steps in institute comprises the following step:

One YUV to RGB switch process is described rgb pixel with a YUV pixel transitions.

13. image color method of adjustment as claimed in claim 12 is characterized in that, a laggard in steps step comprises the following step in institute:

One UV switch process is according to U value and the V value of described output factor to adjusting described YUV pixel.

14. image color method of adjustment as claimed in claim 11 is characterized in that, in the described saturation computation step, the saturation that produces described rgb pixel is:

Sat＝fix{[1-3*min(R，G，B)/(R+G+B)]*255}，

Wherein, R, G, B are respectively red value, green value and the blue valve of described pixel, and min () is a minimum function, and fix is the ceiling function, and Sat is the saturation of described rgb pixel.

15. image color method of adjustment as claimed in claim 11 is characterized in that, in the described colourity calculation procedure, the colorimeter formula that produces described rgb pixel is:

$\mathrm{Hue}=\left\{\begin{array}{cc}\mathrm{\θ},& B\≤G\\ 360-\mathrm{\θ},& B>G,\end{array}\right.$

Wherein, $\mathrm{\θ}={\cos }^{-1}\{0.5*[(R-G)+(R-B)]/{[{(R-G)}^2+(R-B)(G-B)]}^{\frac{1}{2}}\},$ R, G, B are respectively red value, green value and the blue valve of described rgb pixel, and Hue is the colourity of described rgb pixel.

16. image color method of adjustment as claimed in claim 11 is characterized in that, described first tables look-up in the step, and described first table look-up device is erasable storage device.

17. image color method of adjustment as claimed in claim 11 is characterized in that, described second tables look-up in the step, and described second table look-up device is erasable storage device.

18. image color method of adjustment as claimed in claim 13 is characterized in that, and is when the saturation of described pixel is preset saturation less than one the 3rd, that described output factor is right to being set at the described first adjustment coefficient.

19. image color method of adjustment as claimed in claim 18, it is characterized in that, when the saturation of described rgb pixel was preset saturation greater than one the 4th, described output factor is right to being set at the described second adjustment coefficient, and the described the 3rd default saturation was less than the described the 4th default saturation.

20. image color method of adjustment as claimed in claim 19 is characterized in that, when the saturation of described rgb pixel was preset saturation greater than the described the 3rd default saturation and less than the described the 4th, described output factor was to being:

α×table1_value+(1-α)×table2_value，

Wherein, table1_value is that the first adjustment coefficient is right, and table2_value is that the second adjustment coefficient is right, 0≤α≤1.

Images