TWI531246B - Color adjustment method and its system - Google Patents

Description

Color adjustment method and system thereof

The invention relates to a color adjustment method and a system thereof, in particular to a color saturation adjustment method and a system thereof, so that when the intensity of the color (Intensity or Luminance) changes, the saturation degree also follows Change in brightness.

With the advancement of technology, imaging has moved toward digital and high quality. In order to meet the needs of people for high quality and bright colors in the future, the way of color adjustment will be more and more important.

At present, when performing color adjustment, there are basically two ways. One is to directly process the RGB information to increase or decrease the value of the RGB information. The advantage is that directly calculating the RGB information can save a lot of color conversion time. However, since the color adjustment is to directly calculate the RGB information, it is easy to over-saturate during the adjustment, so that the adjusted image color often has an unnatural condition and does not conform to the human visual characteristics.

For example, Capra A. proposed "Dynamic range optimization by local contrast correction and histogram image analysis" in the 2006 International Consumer Electronics Conference, which can effectively adjust the shadow and high-brightness parts at the same time, but at the same time make the whole sheet The contrast and color of the image produced an unnatural phenomenon; as in Yadong Wu. at the 2010 International Conference on Image and Signal Processing, "An image illumination The correction algorithm based on tone mapping" can effectively improve the contrast and saturation of the image, but the problem of exposure and supersaturation is likely to occur in the high-luminance portion.

The other way is to convert the color information into Intensity or Luminance, Saturation and Hue information, and according to the current image information, if the image is too dark or too bright, or the image saturation is too high and too low ...and image information to adjust the brightness, saturation and hue independently. For example, in the 2007 IEEE International Conference on Image Processing, Yihua Shi. proposed "Reducing Illumination Based on Nonlinear Gamma Correction" to adjust image brightness using adaptive gamma curves, but in color vividness and saturation. The performance is weaker, and while adjusting the brightness, if the saturation is not corrected at the same time, it is prone to over-saturation; and, as Yi-Chong Zeng at the 2008 IEEE International Conference on Circuits and Systems, the proposed "Video enhancement" Based on saturation adjustment and contrast enhancement, the luminance and saturation are separately enhanced, and the brightness and the saturation during the adjustment process are not related, so that the overall color continuity is not good, and the image is prone to unnaturalness. Therefore, when the brightness, saturation, and hue are individually adjusted, the overall effect cannot be achieved because the overall effect cannot be achieved, and the over-saturation is likely to occur, resulting in an unnatural picture.

The inventor, in view of this, in the spirit of active invention, considers a "color adjustment method and system" that conforms to human vision, so that when the brightness of the image changes, its saturation will correspond with the change of brightness. Adjustments, after several research experiments, to complete the invention of the Jiahui world.

In view of the prior art, the brightness, saturation, and hue information of the image are individually adjusted, resulting in image oversaturation and poor overall color continuity, which makes the image unnatural. In the color space model, the color saturation, the brightness and the brightness of the image are used to change the brightness of the image, and the saturation is also regularly adjusted. It can effectively avoid color oversaturation, and it is unnatural due to discontinuous image, which is more in line with human visual characteristics.

In addition, if the color space model is based on the component color difference (YCbCr) color space, it can be widely used in most of today's digital image products, such as Liquid Crystal Display Television (LCD-TV), and high. High Definition Television (HD-TV) and the like. It can also be applied to image pre-processing. Moreover, since the amount of calculation of the YCbCr color space is not large, the color adjustment system of the present invention can be integrated to process images in real-time.

To achieve the above object, the present invention provides a color adjustment method comprising the steps of: (A) capturing an image signal having a first color space, and converting the image signal to a second color space such that the image signal corresponds to a color point in the second color space (ie, a coordinate point of the second color space), and the color point has a hue value, a saturation value, and a brightness value; (B) when the brightness value changes, a Representing a new brightness value after the brightness value is changed, and selecting one of the color gamut blocks corresponding to the second color space according to the hue value and the saturation value of the color point, wherein each color gamut block has a feature vertice, Indicates the luminance value and saturation value in each gamut block (C) in the gamut block, according to the saturation value, the brightness value, the new brightness value, and the feature vertices, a new saturation value is generated to represent the saturation value when the brightness value is changed. Correspondingly adjusted to a new saturation value; and (D) generating a new color point including a hue value, a new saturation value, and a new brightness value, and converting the new color point from the second color space back to the first color space output .

In addition, the first color space of the present invention may be a three-color (RGB) color space having a red (R) axis, a green (G) axis, and a blue (B) axis.

Furthermore, the second color space of the present invention can be divided into at least one gamut block according to the hue value.

Furthermore, the second color space of the present invention may be an HSL color space having a Hue, a Saturation, and a Lightness; it may have a Hue (Hue) ), a saturation axis (Saturation), and a HSV color space of a tone color (Value); or may be a YUV color space having a Luminance, Chrominance axis.

Furthermore, the second color space of the present invention may be a component color difference (YCbCr) color space having a luminance (Y) component, a blue offset (Cb) component, and a red offset (Cr) component. And the YCbCr color space can be divided into six gamut blocks, which are one of the magenta domain blocks representing the magenta phase, one red domain block representing the red phase, one yellow domain block representing the yellow phase, and representing the green phase. One green domain block, one green-green domain block representing a cyan phase, and one blue domain block representing a blue phase.

Furthermore, the YCbCr color space of the present invention can be cut according to the three-dimensional regions covered by the Y component, the Cb component, and the Cr component to generate at least one hue triangle for each color gamut block, and each hue triangle includes a bottom edge. , one side, one upper side, and each bottom side is the same.

Furthermore, each color gamut block of the present invention may be selected from the lower side of each hue triangle as the lower side of the maximum slope as a feature lower side, and from the upper side of each hue triangle, the upper side of the minimum slope is selected as a feature upper side. And forming feature vertices at the intersection of the feature and the upper edge of the feature, and in each gamut block, generating a feature triangle including a bottom edge, a feature lower edge, a feature upper edge, and a feature vertice to represent each color gamut block. The relationship between hue, saturation, and brightness. This prevents over-saturation from occurring during color adjustment.

Furthermore, the slope limit of the lower side of the present invention may be the lower slope ≧1, and the slope limit of the upper side may be the upper slope ≦-1, that is, when the color is adjusted, the amount of change of the brightness is greater than or equal to the change of the saturation to match The characteristics of human vision.

In addition, the new saturation value of the present invention can be described by the following expression: S'=S×(S _after /S _before ), where S' is a new saturation value, S is a saturation value, and S _before is a first operational parameter, and S _after is a second operational parameter; and S _before is described by the following expression: S _before = (x / y) × V, V ≦ y; S _before = (x / (y- 255)) × (V-255 ), V> y, which, x, y system wherein the color gamut of the color point located at the vertex, and a luminance value V system; and the S _after operation compared by the following expression: S _after =(x/y)×V',V'≦y;S _after =(x/(y-255))×(V'-255), V'>y, where x and y are colors The point is at the characteristic vertices of the color gamut, and V' is the new brightness value.

To achieve the above object, the present invention provides a color adjustment system including a first color space conversion unit, a storage unit, a saturation adjustment unit, and a second color space conversion unit. The first color space conversion unit captures an image signal of a first color space generated by an image capturing device to convert the image signal from the first color space to a second color space, and correspondingly generates a color point, and the color point has a hue value, a saturation value, and a brightness value; a storage unit stores at least one color gamut block of the second color space, and at least one color gamut block is distinguished according to the hue value Forming a second color space, and each gamut block has a feature vertice; a saturation adjustment unit determines whether the brightness value changes, if any, according to the saturation value, the brightness value, the new brightness value, and the feature vertices, Generating a new saturation value and outputting a new color point, and the new color point has a hue value, a new saturation value, and a new brightness value representing a change in the brightness value; and a second color space conversion unit that will be new The color point is converted from the second color space back to the first color space output; wherein the feature vertex is used to represent the relative relationship between the brightness value and the saturation value in each color gamut block While the color point to adjust the brightness value, the saturation value is adjusted to correspond to the new saturation value.

The above summary and the following detailed description are exemplary in order to further illustrate the scope of the claims. Other objects and advantages of the present invention will be described in the following description and drawings.

Please refer to FIG. 1 , which is a structural diagram of a color adjustment system according to a preferred embodiment of the present invention. As shown in FIG. 1 , the color adjustment system 100 includes a first color space conversion unit 110 , a storage unit 120 , a saturation adjustment unit 130 , and a second color space conversion unit 140 . The first color space conversion unit 110 captures an image signal Im having a first color space generated by the image capturing device 10 to convert the image signal Im from the first color space to a second color space. And correspondingly generating a color point Tm in the second color space, and the color point Tm has a hue value, a saturation value, and a brightness value.

In the embodiment, the image capturing device 10 is a camera to capture the external image information to generate the image signal Im to the first color space converting unit 110. The first color space is an RGB color space having a red (R) axis, a green (G) axis, and a blue (B) axis.

The second color space is a YCbCr color space having a luminance (Y) component, a blue offset (Cb) component, and a red offset (Cr) component. Of course, it can also be other color space models, such as an HSL color space model with a Hue, a Saturation, and a Lightness; for having a Hue axis (Hue) , a saturation axis (Saturation), and a hue axis (Value) HSV color space model; or have a luminance axis (Luminance), two color difference axis (Chrominance) YUV color space model...equal color space model to segment the color information of brightness, saturation, and hue.

For convenience of explanation, the following description will be made with the second color space as the YCbCr color space.

The storage unit 120 is configured to store at least one color gamut block of the second color space, and at least one color gamut block is formed into a second color space according to the hue value, and each gamut block has a feature vertice. In order to adjust the color more simply and efficiently, in the embodiment, the YCbCr color space is divided into several color gamut blocks by using the Cb-Cr plane, and the gamut blocks are not the same size but different colors. Domain blocks have their own different color characteristics to distinguish them to provide more efficient adjustments, as further explained below.

As shown in FIG. 3, the RGB color space has six endpoints on the Cb-Cr projection plane of the YCbCr color space, that is, magenta M (magenta), red R (red), and yellow Ye (yellow) of the RGB color space. The hue endpoints of green G (green), cyan C (cyan), and blue B (blue). In this embodiment, the RGB color space is used to convert the YcbCr color space, and then the Cb component and the Cr component are intercepted, and the range of each color gamut block is obtained by another arithmetic expression, and the operation formula is as follows: Y=0.2989 ×R+0.5866×G+0.1145×B; Cb=-0.1688×R-0.3312×G+0.5000×B; Cr=0.5000×R-0.4184×G-0.0816×B; Div=tan ^-1 (Cr/Cb) Where R, G, B are the coordinates of a certain pixel in the RGB color space; Y, Cb, Cr are the corresponding coordinate values of the RGB color space corresponding to the YCbCr color space; and Div is the distinction of the color gamut block value.

In the embodiment, the distinguishing manner is the point of the end point of the B color phase and the end point of the M color phase, the end point of the M color phase end point and the end point of the R color phase end point, the end point of the R color phase end point and the middle point of the Ye color phase end point, Ye The Cb-Cr plane (with the Cb component right) is the point of the hue end point and the G color end point, the G color end point and the C color end point, and the C color end point and the B color end point. The square starts to calculate 0 to 359 degrees) and is divided into 6 gamut blocks. The Div discrimination value is obtained by taking the B color phase end point and the M color phase end point as an example. The point coordinates of the B color phase end point and the M color phase end point are (R, G, B) = ( 128,0,255), so the Div discriminant value is 22 degrees when substituting the above expression; and the Div discriminant value here is obtained by the midpoint of the M color phase end point and the R color phase end point, M color phase The coordinates of the endpoints of the endpoint and the R phase are (R, G, B) = (255, 0, 128). Substituting the above expression gives a Div discrimination value of 80 degrees.

Therefore, the Div discriminant value of the point among the endpoints of each adjacent hue is calculated sequentially, and the Cb-Cr projection plane of the YCbCr color space can be divided into six gamut blocks, respectively representing the magenta phase M. The red domain block (22 degrees to 79 degrees on the Cb component), the red domain block representing the red phase R (80 degrees to 137 degrees on the Cb component), and the yellow domain block representing the yellow phase Ye (Cb) The component is 138 degrees to 201 degrees), represents a green domain block of green phase G (202 degrees to 258 degrees on the Cb component), and represents a blue-green domain block of cyan phase C (259 degrees on the Cb component) ~318 degrees), and represents a blue domain block of blue phase B (319 degrees to 21 degrees on the Cb component). And as can be observed from the above, the area of the six gamut blocks The area is not the same. Of course, other arithmetic expressions can be used to distinguish the gamut blocks, or the area of each gamut block is the same.

In addition, the feature vertex is used to indicate the relative relationship between the luminance value and the saturation value in each color gamut block, and when the brightness value of the color point is adjusted, the saturation value is correspondingly adjusted to the new saturation value. Similarly, in the present embodiment, the second color space is used as the YCbCr color space, as shown in FIGS. 4a to 4c, the YCbCr color space is based on the Y component, and the black color of the RGB color space is Bk (Black). The connection between the end of the hue and the end of the white W (White) hue, coaxial with the Y component of the YCbCr color space, and 360 degrees of the area covered by the Cb and Cr components, for each gamut The block generates at least one hue triangle Hta. In the present embodiment, since the YCbCr color space is divided into six gamut blocks, the dicing is performed in units of one degree. Therefore, each gamut block can be cut into a plurality of hue triangles Hta (in this embodiment, 58 magenta domain blocks, 58 red domain blocks, 64 yellow domain blocks, and green domains) There are 58 blocks, 58 blocks in the cyan field, and 64 blocks in the blue field, and each hue triangle Hta has a bottom Bs, a lower edge Ds, an upper side Us, and a plurality of hue. The triangles Hta are all the same bottom edge Bs, that is, each bottom edge Bs is the same. Among them, the horizontal axis represents saturation and the vertical axis represents brightness.

Next, each gamut block (six in this embodiment) is selected from the lower side of the maximum slope by the lower side Ds of each hue triangle Hta (Fig. 4b, the hue triangle Hta1-Hta58 of the magenta domain block). Ds is used as a feature lower edge Df, and from the upper side Us of each hue triangle, the upper side of the minimum slope Us is selected as a feature upper side Uf, and the feature lower side Df and the feature upper side Uf A feature vertice P is formed at the fork, and in each gamut block, a feature triangle Fta including a bottom edge Bs, a feature lower edge Df, a feature upper edge Uf, and a feature vertex P is generated. That is, the six gamut blocks have a characteristic triangle Fta sufficient to represent their corresponding gamut blocks. Further, the relative relationship between the luminance value and the saturation value in each color gamut block is obtained. In addition, in the human eye, the brightness changes to be greater than the saturation change. Here, the present invention limits the slope of the feature lower side Df to the characteristic lower side Df slope ≧1, and the characteristic upper side Uf slope is limited to the characteristic upper side Uf slope ≦ -1 to make the feature triangle Fta more in line with human visual characteristics. Of course, the slope of the lower Ds of each hue triangle Hta is limited to the lower side Ds slope ≧1, and the upper side Us slope is limited to the upper side Us ≦-1, which can achieve the same effect and purpose.

Referring to FIG. 5a, 5b at the same time, the saturation adjustment unit 130 will determine whether the brightness value has changed, and if so, the new brightness value V' after the change according to the saturation value S, the brightness value V, and the representative brightness value V. And the characteristic vertices P of the characteristic triangle Fta, to generate a new saturation value S' by using the following expression, and generating a new color point having a hue value, a new saturation value S', and a new brightness value V' Nm to the second color space conversion unit 140, thereby achieving the purpose of correspondingly adjusting the saturation according to the change in brightness. The new saturation value S' is described by the following expression: S'=S×(S _after /S _before ); among them, S′ is the new saturation value, S is the saturation value, and S _before is one. The first operational parameter, and S _after is a second operational parameter.

The S _before is described by the following expression: S _before = (x / y) × V, V ≦ y; S _before = (x / (y - 255)) × (V - 255), V >y; x and y are the coordinates of the characteristic vertices P of the associated feature triangle Fta, and V is the luminance value.

And S _after is operated by the following expression: S _after = (x / y) × V', V' ≦ y; S _after = (x / (y - 255)) × (V'-255), V'>y; where x and y are the coordinates of the characteristic vertices P of the associated feature triangle Fta, and V' is the new brightness value.

Finally, the second color space conversion unit 140 converts the new color point Nm from the second color space back to the first color space. In this embodiment, the YCbCr color space is converted back to the RGB color space, and then output to the display device 20 for display. .

Next, please refer to FIG. 2 at the same time, which is a flowchart of a color adjustment method according to a preferred embodiment of the present invention. For convenience of explanation, the first color space referred to below will be exemplified by the RGB color space, and the second color space will be exemplified by the YCbCr color space for further explanation.

First, the color adjustment system 100 receives the image signal Im to the RGB color space conversion unit 110 having the RGB color space intercepted by the image capturing device 10 (step S210). Next, the RGB color space to conversion unit 110 converts the image signal Im into the YCbCr color space such that the image signal Im corresponds to one of the color points Tm in the YCbCr color space, that is, the coordinate point in the YcbCr color space. And the color point Tm has a hue value, a saturation value, and a brightness value, and is sent to the saturation adjustment unit 130 (step S220).

Further, the saturation adjusting unit 130 determines whether or not the brightness value of the color point has changed (step S230). When the brightness value has not changed, the color point Tm is directly converted from the YCbCr color space back to the RGB color space, and output to the display device 20 for display (step S240). When the brightness value is changed, the saturation adjusting unit 130 generates a new brightness value therein (step S250), and selects one color gamut corresponding to the YCbCr color space according to the hue value and the saturation value of the color point Tm. A block, such as a red domain block (step S260). Then, according to the characteristic vertices of the characteristic triangle corresponding to the red region, and substituting the saturation value, the brightness value, and the new brightness value into the expression of the new saturation value, a new saturation value corresponding to the new brightness value is generated. (Step S270). Then, the saturation adjustment unit 130 generates a new color point including the hue value, the new saturation value, and the new brightness value to the second color space conversion unit 140, and converts the new color point from the YCbCr color space to the RGB color. The space is output to the display device 20 for display (step S280).

Therefore, it can be seen from the above that the present invention provides a color adjustment method and system for the change of brightness, and provides a color adjustment method and system, thereby effectively avoiding the problem of color oversaturation and solving image unnaturalness. Human visual characteristics. In addition, based on the YCbCr color space for color adjustment, it can be applied to digital image products such as LCD-'TV, or HD-TV... Moreover, since the amount of calculation of the YCbCr color space is not large, the color adjustment system of the present invention can be integrated, and the image can be processed in a real-time manner.

The above-mentioned embodiments are merely examples for convenience of description, and the scope of the claims is intended to be limited to the above embodiments.

100‧‧‧Color adjustment system

110‧‧‧First color space conversion unit

120‧‧‧ storage unit

130‧‧Saturation adjustment unit

140‧‧‧Second color space conversion unit

10‧‧‧Image capture device

20‧‧‧ display device

M‧‧‧ magenta end point

R‧‧‧red phase endpoint

Ye‧‧‧Yellow phase endpoint

G‧‧‧Green phase endpoint

C‧‧‧Blue-green phase endpoint

B‧‧‧Blue phase endpoint

Bk‧‧‧black phase endpoint

W‧‧‧White phase endpoint

Y‧‧‧Brightness component

Cb‧‧‧blue offset component

Cr‧‧‧Red offset component

Hta‧‧ Hue triangle

Bs‧‧‧Bottom

Ds‧‧‧ below

Us‧‧‧上上

Uf‧‧‧ features above

Under the characteristics of Df‧‧‧

P‧‧‧ feature vertices

Fta‧‧‧Feature triangle

S‧‧‧ saturation value

V‧‧‧ brightness value

S'‧‧‧ new saturation value

V'‧‧‧ new brightness value

1 is a block diagram of a color adjustment system in accordance with a preferred embodiment of the present invention.

2 is a flow chart of a color adjustment method in accordance with a preferred embodiment of the present invention.

3 is a schematic diagram of a gamut block of a YCbCr color space in accordance with a preferred embodiment of the present invention.

4a is a schematic diagram of a hue triangle cut of a color gamut block in accordance with a preferred embodiment of the present invention.

4b is a schematic diagram of a plurality of hue triangles of a magenta domain block in accordance with a preferred embodiment of the present invention.

Figure 4c is a schematic diagram of a characteristic triangle of a preferred embodiment of the present invention.

Figure 5a is a diagram showing the relationship between the luminance value, the new luminance value, the saturation value, and the new saturation value of the characteristic triangle of a preferred embodiment of the present invention.

Figure 5b is a graph showing the relationship between the luminance value, the new luminance value, the saturation value, and the new saturation value of the characteristic triangle of a preferred embodiment of the present invention.

100‧‧‧Color adjustment system

110‧‧‧First color space conversion unit

120‧‧‧ storage unit

130‧‧Saturation adjustment unit

140‧‧‧Second color space conversion unit

10‧‧‧Image capture device

20‧‧‧ display device

Claims (18)

A color adjustment method includes the following steps: (A) capturing an image signal having a first color space, and converting the image signal to a second color space, such that the image signal corresponds to the second color space a color point, and the color point has a hue value, a saturation value, and a brightness value; (B) when the brightness value changes, generating a new brightness value representative of the brightness value change, and according to the color The hue value of the dot and the saturation value are selected to correspond to one of the second color spaces, wherein each color gamut block has a feature vertex to indicate the brightness in each color gamut block a relative relationship between the value and the saturation value; (C) generating a new saturation value according to the saturation value, the brightness value, the new brightness value, and the feature vertex in the color gamut block, Representing that when the brightness value is changed, the saturation value is correspondingly adjusted to the new saturation value; and (D) generating a new color point including the hue value, the new saturation value, and the new brightness value. And the new color point is taken by the second color Space color space conversion back to the first output; wherein the saturation value of new lines described by the following expression: S '= S × (S after / S before); which, S' new saturation value for the system, S The saturation value, S _before is a first operation parameter, and S _after is a second operation parameter; and S _before is described by the following expression: S _before = (x / y) × V, V ≦ y; S _before =(x/(y-255))x(V-255), V>y; wherein x and y are the characteristic vertices of the color gamut in which the color point is located, and V is the luminance value And S _after is operated by the following expression: S _after -(x/y)×V',V'≦y;S _after -(x/(y-255))×(V'-255),V'>y; where x and y are the characteristic vertices of the color gamut where the color point lies, and V' is the new brightness value. The color adjustment method according to claim 1, wherein the first color space is a three-color color having a red (R) axis, a green (G) axis, and a blue (B) axis. (RGB) color space. The color adjustment method of claim 1, wherein the second color space is divided into the at least one color gamut block according to the color phase value. The color adjustment method according to claim 3, wherein the second color space is an HSL color space having a hue axis, a saturation axis, and a brightness state. ; has an HSV color space with a Hue, a Saturation, and a Tone; or a YUV with a Luminance and Chrominance Color space. The color adjustment method of claim 3, wherein the second color space has a luminance (Y) component, a blue offset (Cb) component, and a red offset (Cr) component. Component color difference (YCbCr) color space. The color adjustment method according to claim 5, wherein the second color space is divided into six color gamut blocks, respectively representing a magenta domain block representing a magenta phase, and representing a red color of the red phase. The domain block, a yellow domain block representing a yellow phase, a green domain block representing a green phase, a green-green domain block representing a cyan phase, and a blue domain block representing a blue phase. The color adjustment method according to claim 5, wherein the YCbCr color space is cut according to the Y component, the Cb component, and a three-dimensional region covered by the Cr component, to generate each color gamut block. At least one hue triangle, and each hue triangle includes a bottom edge, a lower edge, an upper edge, and each bottom edge is the same. The color adjustment method according to claim 7, wherein each color gamut block is selected from the lower side of each hue triangle, and the lower side of the maximum slope is selected as a feature lower edge, and each color phase triangle is In the upper edge, the upper edge of the minimum slope is selected as a feature upper edge, and the feature vertex is formed at the intersection of the feature and the upper edge of the feature, and in each color gamut block, a bottom edge is generated. The feature triangle at the bottom of the feature, the top edge of the feature, and the vertices of the feature. The color adjustment method according to claim 8, wherein the slope of the lower side of the feature is limited to the lower slope ≧1 of the feature, and the slope of the upper side of the feature is limited to the upper slope ≦-1 of the feature. A color adjustment system includes: a first color space conversion unit that captures an image signal generated by an image capturing device and has a first color space to convert the image signal from the first color space to a first color space a color space corresponding to a color point, wherein the color point has a hue value, a saturation value, and a brightness value; and a storage unit stores at least one color gamut block of the second color space, and the at least a color gamut block is distinguished according to the hue value, and constitutes the second color space, and each gamut block has a feature vertice; a saturation adjustment unit determines whether the brightness value changes, if any, according to the a saturation value, the brightness value, the new brightness value, and the feature vertices, generating a new saturation value, and outputting a new color point, and the new color point has the color value, the new saturation value, and the representative a new brightness value after the brightness value is changed; and a second color space conversion unit that converts the new color point from the second color space back to the first color space output; wherein the feature The point is used to indicate the relative relationship between the brightness value and the saturation value in each color gamut block, and when the brightness value of the color point is adjusted, the saturation value is correspondingly adjusted to the new saturation value. Wherein, the new saturation value is described by the following expression: S'=S×(S _after /S _before ); wherein, S′ is the new saturation value, and S is the saturation value, S _before It is a first operation parameter, and S _after is a second operation parameter; and S _before is described by the following expression: S _before = (x / y) × V, V ≦ y; S _before = (x / ( Y-255))×(V-255), V>y; wherein x and y are the characteristic vertices of the color gamut in which the color point is located, and V is the brightness value; and S _after is the following expression Operation: S _after =(x/y)×V',V'≦y;S _after =(x/(y-255))×(V'-255), V'>y; among them, x, y It is the characteristic vertice of the color gamut where the color point is located, and V' is the new brightness value. The color adjustment system of claim 10, wherein the first color space is a ternary color having a red (R) axis, a green (G) axis, and a blue (B) axis. (RGB) color space. The color adjustment system of claim 10, wherein the second color space is an HSL color space having a Hue, a Saturation, and a Lightness. ; has an HSV color space with a Hue, a Saturation, and a Tone; or a YUV with a Luininance and Chrominance Color space. The color adjustment system of claim 10, wherein the second color space has a luminance (Y) component, a blue offset (Cb) component, and a red offset (Cr) component. Component color difference (YCbCr) color space. The color adjustment system of claim 13, wherein the second color space is divided into six color gamut blocks, one of which represents a magenta phase, and one of the red phases. The domain block, a yellow domain block representing a yellow phase, a green domain block representing a green phase, a green-green domain block representing a cyan phase, and a blue domain block representing a blue phase. The color adjustment system of claim 13, wherein the YCbCr color space is cut according to the Y component, the Cb component, and a three-dimensional region covered by the Cr component to generate each color gamut block. At least one hue triangle, and each hue triangle includes a bottom edge, a lower edge, an upper edge, and each bottom edge is the same. The color adjustment system of claim 15, wherein the slope of the lower side is limited to the lower slope ≧1, and the slope of the upper side is limited to the upper slope ≦-1. The color adjustment system of claim 15 or claim 16, wherein each color gamut block is selected from the lower side of each hue triangle, and the lower side of the maximum slope is selected as a feature lower edge, and each In the upper side of the chromatic phase triangle, the upper edge of the minimum slope is selected as a feature upper edge, and the feature vertice is formed at the intersection of the feature lower edge and the upper edge of the feature, thereby generating a inclusion in each gamut block. The bottom edge, the lower edge of the feature, the upper edge of the feature, and the characteristic triangle of the feature vertex. The color adjustment system of claim 17, wherein the slope of the lower side of the feature is limited to a feature lower slope ≧1, and a slope of the upper side of the feature is limited to a characteristic upper slope ≦-1.