METHOD OF PROCESSING BRIGHTNESS OF AN IMAGE AND RELATED DEVICE

Abstract

Brightness values of image frames are collected and counted to form a brightness distribution. The brightness distribution of the image frames is compared with predetermined brightness distributions. Brightness values of all pixels of successive image frames are adjusted according to a result of the comparison, so as to improve image contrast.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an image processing device according to the prior art.

FIG. 2 is a block diagram of an image processing device according to the present invention.

FIG. 3 to FIG. 6 are predetermined brightness distributions.

FIG. 7 is a brightness distribution of an image.

FIG. 8 is a graph of a brightness adjustment function.

FIG. 9 is the brightness distribution in FIG. 7 after being adjusted with the brightness adjustment function of FIG. 8.

FIG. 10 is a flowchart of a method of image processing according to the present invention.

Claims

1. A method for processing brightness of an image comprising: generating a brightness distribution of a plurality of pixels of the image according to brightness values of the pixels;determining whether a difference between the brightness distribution of the pixels and a predetermined brightness distribution is within a predetermined range; andif the difference between the brightness distribution of the pixels and the predetermined brightness distribution is within the predetermined range, adjusting brightness values of upcoming pixels according to a transformation rule corresponding to the predetermined brightness distribution.

2. The method of claim 1 wherein generating the brightness distribution of the plurality of pixels according to the brightness values of the pixels comprises calculating a number of pixels whose brightness value is within a predetermined brightness interval.

3. The method of claim 2 wherein determining whether the difference between the brightness distribution of the pixels and the predetermined brightness distribution is within the predetermined range comprises: determining whether the difference between the brightness distribution of the pixels and the predetermined brightness distribution is within a predetermined range according to an equation

4. The method of claim 1 wherein adjusting the brightness values of the upcoming pixels according to the transformation rule comprises using a transformation function to transform the brightness values of the upcoming pixels.

5. The method of claim 1 wherein adjusting the brightness values of the upcoming pixels according to the transformation rule comprises adjusting the brightness values of the upcoming pixels according to a look-up table.

6. The method of claim 1 wherein generating the brightness distribution of the pixels comprises collecting data on brightness values of a plurality of pixels of an image.

7. The method of claim 1 wherein generating the brightness distribution of the pixels comprises collecting data on brightness values of pixels of a plurality of images.

8. An image processor for adjusting a brightness of images, the image processor comprising: a brightness comparator for comparing a brightness distribution of a plurality of pixels with a plurality of predetermined brightness distributions; anda brightness gain unit for adjusting gains of brightness values of pixels of an upcoming image according to a transformation rule corresponding to one of the predetermined brightness distributions with which the brightness distribution of the pixels compares.

9. The image processor of claim 8 further comprising a brightness accumulation memory unit for accumulating brightness values of the pixels.

10. The image processor of claim 9 further comprising a timing accumulation memory unit for controlling the brightness accumulation memory unit to accumulate the brightness values of the pixels.

11. The image processor of claim 8 further comprising a static random access memory (SRAM) for storing the predetermined brightness distributions.

12. The image processor of claim 8 further comprising a static random access memory (SRAM) for storing the transformation rule.