An Adaptive Image Enhancement Technique Based on Image Characteristic

A novel adaptive image enhancement technique based on image characteristic is proposed in this paper. At first, the spatial high-pass filter (the Laplace filter) is applied to the original image data. Then, the first-order classifying of the image is employed on the basis of the specification of the output of the Laplace filter. The low-pass filter is applied to smooth the image for the high threshold image and the high-pass filter is applied to sharpen the edge of the image for the low threshold image. After that, the second-order classifying is used to adjust the brightness of the image based on the histogram of the output of the first-order classifying. At last, the histogram equalization is applied to the image for fitting our eyes. This technique is implemented on FPGA of Xilinx Virtex4, and performs successfully.