TWI271686B - Apparatus and method for adjusting brightness - Google Patents

Abstract

The invention discloses an apparatus for adjusting the output back light used for displaying the ith image frame of an imputed image sequence in a display system. The apparatus includes a light sensing module, a memory unit, an image processing module, and a back light module. The light sensing module is used for sensing a current environmental light. The memory unit is used for storing a look-up table, and the look-up table records a plurality of environmental light each of which corresponds to a plurality of brightness ratios and back light adjusting parameters. The image processing module is used for calculating a current brightness ratio of the ith image frame and, according to the current environmental light, the current brightness ratio and the look-up table, further determining a back light parameter. The back light module is used for adjusting the output back light based on the determined back light parameter.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brightness adjusting device and a method thereof, and more particularly to adjusting an input video sequence in a display system. Brightness adjusting device for output brightness and method thereof. [Prior Art] The brightness of a liquid crystal display (LCD) is generated by a backlight module. By controlling the twist of the liquid crystal, the transmittance of the backlight can be changed to determine the brightness of the image. At present, LCD display methods are mostly based on cold cathode fluorescent lamps (CCFLs). When the user is viewing the bright picture on the LCD in a dark ambient light, the eyes may feel uncomfortable because the light is too strong. When the LCD is used to view the dark surface, since the brightness of the backlight is a fixed brightness, the contrast of the entire surface is reduced. Standing in the first rhyme technique, the existing LCD uses a light sensor to sense the ambient light, and then adjust the backlight brightness as the ambient light changes. However, the above-mentioned prior art ‘only for the ring i brother light to § the whole backlight, there is no adjustment according to the brightness of the face. Spring _ When the ambient light is dark and the picture is dark, the contrast will still decrease, and the shadow will be displayed.曰 π j provides a brightness adjusting device and a method thereof, and one of the exemplary arms of the present invention is to provide an output backlight brightness of a brightness adjustment and alignment image. Thereby, a better image quality can be obtained. 1271686 According to a preferred embodiment, an input image sequence (Video sequence) is input to a display system, and the input image sequence includes a video image plane ( Image frame), N is a natural number. The brightness adjusting device of the present invention is for adjusting the output backlight brightness of the i-th image frame in the input image sequence in the display system, i being an integer index in the range of 1 to N. The brightness adjusting device includes a light sensing module, a memory unit, an image processing module, and a backlight module. In the above embodiments, the light sensing module is used to sense the current ambient light. The memory unit is used to store the comparison table (L〇〇k up

Tabl:), the pair of records records a plurality of ambient lights, each ambient light corresponding to a plurality of brightness ratios (Brightness ratio) and a plurality of backlight adjustment parameters (Parameter), each backlight adjustment parameter and the brightness representation The rate corresponds to one of them. The processing module is configured to receive the current ambient light, calculate the front brightness index of the second image, and determine the backlight corresponding to the current brightness rate according to the current ambient light and the current brightness representation ratio. Adjustment parameters. The backlight module is configured to receive the #光光 parameter corresponding to the current bright silk to adjust the output backlight brightness of the i-th image. Like the history of you, the invention of the shell degree adjustment device is based on the change of ambient light and the output backlight brightness of the entire image surface, and then the ambient light can effectively improve the face-to-face ratio. In this way, the preferred embodiment and the spirit can be obtained by the following detailed description of the invention and the accompanying drawings. [Embodiment] Brightness diagram - the functional block diagram of the preferred embodiment according to the present invention . In this implementation, the input image sequence quence is input to the display system (not shown). In 1271686 t ,, the input image sequence contains N image frames, and N is a natural number. The brightness adjusting device 1 of the present invention is for adjusting the output backlight brightness of the i-th image frame in the input image sequence 10 in a display system (not shown), i is! An integer indicator to the range of N. The input image sequence 1 is RGB color space or other color space. As shown in FIG. 1 , the brightness adjusting device 1 includes a light sensing module 12 , an analog to digital converter (AD converter) 14 , a memory unit 16 , and an image processing module. (Image processing module) 18, a digital to analog converter (DA converter) 20, a backlight module (Back light module) 22, and a display module (Display module) 24. In this embodiment, the light sensing module 12 is configured to sense current ambient light. Since the current ambient light sensed by the light sensing module 12 is an analog signal, the analog digital converter 14 is used to convert the current ambient light from an analog signal to a digital signal. Please refer to FIG. 2, which is a schematic diagram of the comparison table 16〇 in FIG. The memory unit 16 is used to store a look-up table (L〇〇k-up table) 160. The comparison table 160 records a plurality of ambient light EL#, and each ambient light EL# corresponds to a plurality of brightness ratios BR# and a plurality of backlight adjustment parameters (Parameter) p#, each backlight adjustment parameter P #All correspond to one of these brightness representation rates BR#. As shown in FIG. 2, the comparison table 160 records 16 ambient light ELrEL16, and each ambient light ELrELi6 corresponds to 6 brightness ratios BRrBR6 and 6 backlight adjustment parameters PlrP16, P21_P26, ..., pi6i, respectively. -Pi66. The image processing module 18 is configured to receive the uranium ambient light converted by the analog digital converter 14. At the same time, the image processing module 18 calculates the current brightness representation rate of the second image frame of the input image sequence, and determines the current brightness according to the current environment 7 1271686 t light received, the current brightness display rate, and the comparison table 16〇. Indicates the backlight adjustment parameter corresponding to the rate. Since the backlight adjustment parameter determined by the image processing module 18 is a digital signal, the digital analog converter 20 converts the backlight adjustment parameter from a digital signal to an analog signal. The backlight module 22 is configured to receive the digital analog converter 20, and then replace the backlight adjustment parameter corresponding to the current brightness representation rate, and adjust the output backlight brightness of the ith image frame accordingly. Finally, the display module 24 displays the second image frame of the input image sequence 1 by the adjusted rounding backlight brightness.

For example, if the current ambient light sensed by the light sensing module 12 is ,^, and the current brightness of the first surface is BR4, the image processing module 18 will be based on the current ambient light EL2. The current brightness representation rate and the comparison table ι6〇, & set the backlight adjustment parameter p24 corresponding to the current brightness representation rate BI. Then, the backlight module 22 adjusts the parameters of the backlight adjustment & adjusts the image of the second image to the rear of the image group 24 to display the image of the image by the adjusted output f brightness. Therefore, the hair brightness adjusting device can adjust the backlight brightness according to the change of the ambient light and the brightness of the image surface, and further, when the ambient light is dark and the back surface is also dark, Effectively improve the picture contrast. ^ In some display systems, before the input image sequence 1 is displayed in the sheet metal display module 24, I will be converted by Gamma to increase the drawing. "Please refer to FIG. 3, and FIG. 3 is a preferred embodiment according to the present invention. And the flow chart of the adjustment method. Please - and refer to Figure 1 to Figure 2, the second method is used in the display system to adjust the input image & brightness adjustment method comprises the following steps: ^ Body embodiment 'The invention Step S100: sensing the current ambient light; Step S1G2: calculating the current brightness table of the i-th image, and the current brightness representation rate of the root f ring and the backlight adjustment parameter corresponding to the daily rate ; , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , i images inside. The degree of brightness is not rounded into the image sequence. Compared with the prior art, the brightness adjusting device of the present invention adjusts the image of the light and the brightness of the image to adjust the image of the image. When it is darker and the back surface is also darker, it can be brightened by t # backlight, which can get better image quality. Hadan face the ratio. The detailed description of the specific embodiments of the present invention is intended to provide a clearer description of the spirit of the present invention, and is not intended to be a preferred embodiment of the invention disclosed above. The broadest interpretation so that it covers all possible changes and equal arrangements. 9 1271686. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a brightness adjusting device according to a preferred embodiment of the present invention. FIG. 2 is a schematic diagram of a comparison table in FIG. 1; and FIG. 3 is a flow chart of a brightness adjustment method according to a preferred embodiment of the present invention.

[Main component symbol description] 1 : Brightness adjusting device 12 : Light sensing module 16 : Memory unit 18 : Image processing module 22 : Backlight module ELrEL16 : Ambient light 10 : Input image sequence 14 : Analog to digital converter 160 : Comparison Table 20: Digital Analog Converter 24: Display Module BRi-BRg: Party Degree Representation Rate

Pu_Pl6, P21-P26, P16rPl66: backlight adjustment parameters S100-S106: process steps

Claims (1)

1271686 X. Patent application scope: l A brightness adjustment device inputs an input image sequence in a display system, the input image sequence includes N image planes, and the brightness adjustment device is used in the display system to adjust the One of the i-th image planes in the input image sequence outputs a backlight vanishing degree, where N is a natural number 'i is an integer index from the range of 1 to N, and the brightness adjusting device comprises: a light sensing module, To sense a current ambient light; a memory unit for storing a comparison table, the comparison table recording a plurality of ambient lights' each of the ambient lights respectively corresponding to a plurality of brightness representation rates and a plurality of backlight adjustment parameters Each of the backlight adjustment parameters corresponds to one of the brightness representation rates; an image processing module is configured to receive the current ambient light and calculate a current brightness representation rate of the one of the second image frames and Determining the backlight adjustment parameter corresponding to the current brightness representation rate according to the current ambient light, the target degree of representation, and the comparison table; and The backlight module is configured to receive the backlight adjustment parameter corresponding to the current brightness representation rate, and adjust the output backlight brightness of the ith image plane. The brightness adjustment device of claim 1, further comprising an analog converter coupled between the light sensing module and the image processing module, wherein the cheek ratio digital converter is used for the light One analog signal of the sensing module output is converted into a digital signal. The brightness adjustment device described in item 1 of the mouth, the step-by-step includes a digital converter, DA converter, and is lightly connected to the fourth item, as described in item 1 of the patent application scope. The brightness adjustment device includes a display 1271686 display module for outputting the ith image plane of the input image sequence by the adjustment. Yue You, U degree,,, and Bay 5, as described in the scope of claim 4, the brightness adjustment device, in front of the display module, will first pass the Ga ~ brother 1 private comparison. Conversion to enhance the picture 6. The brightness adjustment device as described in the fourth aspect of the patent scope, wherein the column conforms to the RGB color space. μ input ~ like sequential input - a brightness adjustment method, inputting an input image in a display system, and the human image sequence includes a plurality of image planes, and in the brightness adjustment system, adjusting the input image sequence The length of the video book, N is a natural number, and i is the range. The whole method consists of the following steps: sensing the first sight as the ambient light; counting the current brightness and expressing the rate according to the current ring. The rate of expression and a comparison table determine the adjustment parameter of the backlight, wherein the reference table i, the solid backlight adjustment parameter, each of the back and the shell table does not rate one of the Corresponding to; and less adjusting the output backlight brightness of the image plane according to the backlight corresponding to the current brightness representation rate. ^ Number I the younger brother! 8. In i, please refer to the brightness adjustment method described in item 7 of the patent scope, and the step further includes the following steps: the brightness of the rim is displayed to display the first sequence of the image sequence of the wheeled image, and the eighth item of the special fiber package is received. Before the display method is displayed, it will pass through the Ga Na Lai to enhance the brother of the 昼 面 ^ ^ 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 The input image sequence conforms to the RGB color space. 13