Polyphase Filter Image Size Conversion Engine Algorithms And Asic Structure

The thesis centers on two types of processing technology - image interpolation and image zooming which are of great importance in image processing. After it analyses present approaches to image interpolation and resizing. The paper gives the results.A. Thesis give a new way to scale the image and video used poly-phase comb filter. This algorithm can be fit to scale gray image and color image. This algorithm can reduce the alias after scaling the image and improve the quality. It can save the edge information. And can be scale in arbiter integer.B. Based on the deep analysis, give a new structure in ASIC based to (1) poly-phase filter, also give how to design the low pass filter which can be fit the ASIC ram base structure. In this structure, first , use color space converter to change the picture from true color (RGB) to (Y CB CR), then reduce CB, CR signal to half rate, so can use half ram to store CB, CR signal. Last, use the comb filter and poly-phase filter to Y, CB, CR signals. The ploy-phase filter is a digital low pass filter which has 128 TAP, divide into 32 phase, has 4 calculate path, only need 4 multiplication.C. At last give the results of still image simulation.