TWI394465B - Display apparatus - Google Patents

Description

Display device

The present invention relates to a display device, and more particularly to a device for displaying image contrast adjustment for a display device.

Today, with the increasing popularity of electronic technology, electronic products have become an indispensable tool in people's lives. In order to provide users with better use quality, a high-performance display device is an essential equipment that is indispensable for today's electronic products.

In order to improve the display performance of the display device, contrast adjustment of the image is an important function. In the conventional technical field, in the case of neglecting the image display content, only a linear image adjustment curve corresponding to the brightness of the input image data and the output image data is proposed as a basis for image contrast adjustment. This linear image adjustment curve is of course quite easy to implement, but since the brightness of the image is dynamically changed. This conventional linear image adjustment curve adjustment technique is not suitable for display images of all brightness. As a result, the display performance is greatly reduced.

Corresponding to this, a conventional technique (for example, U.S. Patent No. 6,870,955) proposes a contrast adjustment of the image by using the nonlinear image adjustment curve 110 as shown in FIG. Since the image adjustment curve 110 is a quadratic curve, it is computationally complicated in implementation. Although the linear image adjustment curve has better performance, the hardware cost of the implementation is higher, and the cost and performance are not considered.

The invention provides a display device, which can dynamically adjust image contrast according to image data.

The invention provides a display device, which comprises an image statistics module, a parameter calculation module and an image adjustment module. The image statistics module receives a plurality of image data, and calculates the number of pixels corresponding to different brightnesses in the image data to obtain a brightness distribution parameter. The parameter calculation module is coupled to the image statistics module for receiving the brightness distribution parameter and searching for the first specific proportion of the set brightness according to the brightness distribution parameter, and searching for the second specific ratio according to the brightness distribution parameter. The first adjustment brightness and the second adjustment brightness of the three specific ratios. The parameter calculation module calculates the brightness correspondence between the piece-wise linear input image data and the output image data according to the set brightness, the first and second adjusted brightness. Wherein, when the input image data is equal to the set brightness, the output image data is equal to the input image data. The image adjustment module is coupled to the parameter calculation module to receive the brightness correspondence and the image data. The image adjustment module adjusts the image data according to the brightness correspondence to generate a plurality of display image data.

In an embodiment of the invention, the first specific ratio is greater than the second specific ratio, and the third specific ratio is greater than the first specific ratio.

In an embodiment of the invention, the first specific ratio is greater than the third specific ratio, and the second specific ratio is greater than the first specific ratio.

In an embodiment of the present invention, when the brightness of the input image data is equal to the first adjusted brightness, the output image data is smaller than the input image data, and the brightness of the input image data is equal to the second adjusted brightness, and the output image data is larger than the input image. data.

In an embodiment of the present invention, when the brightness of the input image data is equal to the first adjusted brightness, the output image data is larger than the input image data, and the brightness of the input image data is equal to the second adjusted brightness, the output image data is smaller than the input image. data.

In an embodiment of the invention, the parameter calculation module further includes a third adjusted brightness for finding at least one of the fourth specific ratios according to the brightness distribution parameter and the at least one fourth specific ratio.

In an embodiment of the invention, when the brightness of the input image data is equal to the third brightness, the output image data is larger or smaller than the input image data.

In an embodiment of the invention, the image adjustment module uses an interpolation algorithm to adjust image data according to the brightness correspondence to generate display image data.

In an embodiment of the invention, the brightness correspondence relationship is a look-up table.

Based on the above, the present invention utilizes a plurality of dynamically received image data to obtain a brightness distribution parameter, and according to the brightness distribution parameter, the brightness occurrence probability is the first, second, and third specific ratios of the set brightness and the first and second brightness adjustments are generated. The linear relationship between the input image data and the segment of the output image data is linear. The image data received immediately is adjusted by the brightness correspondence to generate display image data for display. In this way, the effect of dynamically adjusting the display image contrast can be achieved simply and effectively. Moreover, the adjustment of the shadow display contrast is performed according to the currently displayed image brightness distribution, so that the contrast adjustment is more effective.

The above described features and advantages of the present invention will be more apparent from the following description.

Please refer to FIG. 2. FIG. 2 is a schematic diagram of a display device 200 according to an embodiment of the invention. The display device 200 includes an image statistics module 210, a parameter calculation module 220, and an image adjustment module 230. The image statistics module 210 receives the plurality of image data DIN and calculates the number of pixels corresponding to different brightnesses in the image data DIN to obtain the brightness distribution parameter HIS. Specifically, the image statistics module 210 calculates the total number of pixels corresponding to each of the different brightnesses by calculating a plurality of image data DIN. Please refer to the histogram of the brightness distribution parameter 250 illustrated in FIG. 2A. The horizontal axis of the luminance distribution parameter bar graph 250 is the luminance, and the vertical axis is the total number of pixels corresponding to each luminance. Taking the luminances A1 and A2 as an example, in the video data DIN, there are seven pixels displaying the luminance A1. In the image data DIN, there are 10 pixels with a brightness of A2.

Please note that the image data DIN is a material that dynamically changes as the display screen changes, that is, the brightness distribution parameter 250 is also dynamically changed. The image data DIN used to establish the brightness distribution parameter 250 can be a frame or a plurality of frame materials, and there is no certain limit on the number of image data.

Referring to FIG. 2 again, the parameter calculation module 220 is coupled to the image statistics module 210. The parameter calculation module 220 receives the brightness distribution parameter HIS generated by the image statistics module 210, and searches for the set brightness of the first specific ratio, the first adjusted brightness of the second specific ratio, and the third according to the brightness distribution parameter HIS. A second adjustment of brightness for a particular ratio. here. The so-called first specific ratio, the second specific ratio and the third specific ratio do not limit the scale value, and the designer can set it according to the requirements. The relationship between the first, second and third specific ratios is that the first specific ratio is between the second and third specific ratios, and the second specific ratio may be greater than (not equal to) the third specific ratio or less than the third specific ratio. . For example, the first specific ratio used to find the set brightness can be set to 50%, while the second and third specific ratios can be set to 25% and 75%, respectively.

Referring again to FIG. 2A, in accordance with the above example, in the case where the first, second, and third specific ratios are set to 50%, 25%, and 75%, respectively, the parameter calculation module 220 is based on the bar graph of the brightness distribution parameter 250. It can be found that the set brightness is the brightness C, and the first adjusted brightness and the second adjusted brightness are the brightness A and the brightness B, respectively.

After finding the set brightness, the first adjusted brightness, and the second adjusted brightness, the parameter calculation module 220 obtains the brightness correspondence between the segment linear input image data and the output image data according to the set brightness, the first and second adjusted brightness. Please refer to FIG. 2B. FIG. 2B illustrates the brightness correspondence 280 obtained according to the brightness distribution parameter of FIG. 2A. Wherein, in the brightness correspondence 280, when the input image data is equal to the set brightness (brightness C), the brightness of the output image data and the input image data are equal to the brightness C. That is to say, the set point P1 positioned according to the set brightness C falls between the diagonal lines 281. In addition, in the brightness correspondence 280, when the input image data is equal to the first adjusted brightness (brightness A), the brightness of the corresponding output image data is set to be smaller than the brightness A, that is, according to the first adjusted brightness A. The set point P2 falls below the diagonal 281. Moreover, when the input image data is equal to the second adjusted brightness (brightness B), the brightness of the corresponding output image data is set to be greater than the brightness B, that is, the set point P3 positioned according to the first adjusted brightness B falls in the pair Above the corner 281.

Accordingly, the parameter calculation module 220 only needs to sequentially connect the origin O, the set point P2, the set point P1, the set point P3, and the end point T of the diagonal 281, that is, the brightness correspondence 280 can be obtained.

Please note that the set point P2 located according to the first adjusted brightness A can also be positioned above the diagonal 281, and the set point P3 positioned according to the second adjusted brightness B can also be positioned in the pair. Below the corner 281. The set points P2 and P3 are not limited to the set position, and can be changed according to the needs of the user or the designer.

In addition, since the brightness distribution parameter as the basis for establishing the brightness correspondence 280 is dynamically changed, the brightness correspondence 280 is also dynamically changed.

It is worth noting that in the digital design mode, the brightness correspondence can be implemented by means of a lookup table. In brief, the brightness of the 8-bit resolution is taken as an example, and the data of the brightness of the output image sequentially calculated by the brightness correspondence 280 according to the brightness of the input image is recorded in the lookup table.

In addition, please refer to FIG. 2C. FIG. 2C illustrates another brightness correspondence 290 obtained according to the brightness distribution parameter of FIG. 2B. Among them, in the brightness correspondence 290, different adjusted brightnesses D and E are found in the brightness distribution parameters according to different specific ratios. The brightness correspondence 290 is increased by a plurality of set points P4 and P5. As a result, the turning point of the brightness correspondence 290 will be more than the brightness correspondence 280, which can provide finer image contrast adjustment.

That is to say, the set point on the brightness correspondence 290 in the embodiment of the present invention is not limited to the number thereof, and the number of set points as the turning point can be increased, decreased, and adjusted according to the needs of the designer or the user.

Referring to FIG. 2 again, the image adjustment module 230 is coupled to the parameter calculation module 220 for receiving the brightness correspondence and the image data DIN. The image adjustment module 230 adjusts the image data DIN according to the brightness correspondence to generate a plurality of display image data DOUT for display. Further, when the brightness correspondence is implemented by using a lookup table, the image adjustment module 230 only needs to find the brightness of the corresponding output image according to the received image data DIN as an input image to obtain the displayed image data. DOUT. In addition, when the brightness correspondence is not implemented by the lookup table, since the brightness correspondence is a piece linear curve, the image adjustment module 230 can receive the information of all the set points in the brightness correspondence relationship (the input of the set point) And the brightness of the output image), and according to the information of the two set points adjacent to each image data DIN, the display image data DOUT corresponding to each image data DIN can be obtained.

The above-described interpolation algorithm for performing the interpolation operation is a technique well known to those skilled in the art and will not be described here.

Please refer to FIG. 3 . FIG. 3 is a flow chart showing the operation of the display device according to the embodiment of the present invention. First, image data is received (S310), and then the number of pixels corresponding to different brightnesses in the image data is calculated to obtain a brightness distribution parameter (S320). After obtaining the brightness distribution parameter, the brightness of the first specific ratio is found according to the brightness distribution parameter, and the first adjustment brightness and the second adjustment of the second specific ratio and the third specific ratio are found according to the brightness distribution parameter. The brightness is calculated, and the brightness corresponding to the brightness of the segmented linear input image data and the output image data is calculated (S330). Finally, the image data is adjusted according to the brightness correspondence to generate a plurality of display image data (S340).

In summary, the present invention utilizes a plurality of image data based on dynamic statistics to obtain brightness distribution parameters. The brightness distribution parameter is used to find the set brightness and the brightness of the different ratios of occurrence probability, and the brightness corresponding to the linearity of the input image data and the output image data is calculated according to the set brightness and the adjusted brightness. In this way, the brightness of the input image data can be adjusted according to the dynamically adjusted brightness correspondence to obtain the display image data actually used for display. Excellent contrast adjustment can be achieved in different brightness display screens. Moreover, due to the linear characteristics of the segments of the luminance correspondence, the hardware complexity of the display device is also effectively simplified, and the circuit cost is effectively reduced.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the invention, and any one of ordinary skill in the art can make some modifications and refinements without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.

110‧‧‧Image adjustment curve

200‧‧‧ display device

210‧‧‧Image Statistics Module

220‧‧‧Parameter calculation module

230‧‧‧Image Adjustment Module

250‧‧‧Brightness distribution parameters

280, 290‧‧ ‧ brightness correspondence

281‧‧‧ diagonal

P1~P5‧‧‧ set point

A~E‧‧‧Brightness

HIS‧‧‧Brightness distribution parameters

DIN‧‧ ‧ imagery

DOUT‧‧‧Display image data

S310~S340‧‧‧Compare adjustment steps

FIG. 1 illustrates a non-linear image adjustment curve 110.

FIG. 2 is a schematic diagram of a display device 200 according to an embodiment of the invention.

FIG. 2A is a bar graph of the brightness distribution parameter 250.

FIG. 2B illustrates a brightness correspondence 280 obtained according to the brightness distribution parameter of FIG. 2A.

FIG. 2C illustrates another luminance correspondence 290 obtained according to the luminance distribution parameter of FIG. 2B.

FIG. 3 is a flow chart showing the operation of the display device for performing contrast adjustment according to an embodiment of the invention.

200. . . Display device

210. . . Image statistics module

220. . . Parameter calculation module

230. . . Image adjustment module

HIS. . . Brightness distribution parameter

DIN. . . video material

DOUT. . . Display image data

Claims (10)

A display device includes: an image statistics module, which receives a plurality of image data, and calculates a number of pixels corresponding to different brightnesses in the image data to obtain a brightness distribution parameter; a parameter calculation module coupled to the The image statistics module receives the brightness distribution parameter, searches for a set brightness according to the brightness distribution parameter, and finds the occurrence probability as a second specific ratio and a third specific according to the brightness distribution parameter. a first adjustment brightness and a second adjustment brightness of the ratio, and calculating a brightness correspondence relationship between an input image data of the segment linearity and an output image data according to the set brightness, the first and second adjustment brightness, wherein When the brightness of the input image data is equal to the set brightness, the brightness of the output image data is equal to the brightness of the input image data; and an image adjustment module is coupled to the parameter calculation module to receive the brightness correspondence and the Image data, adjusting the image data according to the brightness correspondence to generate a plurality of display images . The display device of claim 1, wherein the first specific ratio is greater than the second specific ratio, and the third specific ratio is greater than the first specific ratio. The display device of claim 1, wherein the first specific ratio is greater than the third specific ratio, and the second specific ratio is greater than the first specific ratio. The display device of claim 1, wherein the display device When the brightness of the input image data is equal to the brightness of the input image data, and the brightness of the input image data is equal to the second brightness, the brightness of the output image data is greater than the brightness of the input image data. Enter the brightness of the image data. The display device of claim 1, wherein the brightness of the input image data is greater than the brightness of the input image data, and the brightness of the input image data is equal to the brightness of the input image data. When the second brightness is adjusted, the brightness of the output image data is less than the brightness of the input image data. The display device of claim 1, wherein the parameter calculation module further comprises at least one third adjustment for finding the at least one fourth specific ratio according to the brightness distribution parameter and the at least one fourth specific ratio. brightness. The display device of claim 6, wherein the parameter calculation module further adjusts the brightness correspondence according to the at least one third adjustment brightness. The display device of claim 6, wherein the brightness of the input image data is greater than or less than the brightness of the input image data when the brightness of the input image data is equal to the at least one third adjusted brightness. The display device of claim 1, wherein the image adjustment module uses an interpolation algorithm to adjust the image data according to the brightness correspondence to generate the display image data. The display device of claim 1, wherein the brightness correspondence is a lookup table.