DESIGN AND IMPLEMENTATION OF AN ON-LINE CFA DEMOSAICKING CORE

2008

The thesis introduces a low-cost algorithm for improving the demosaicking process in the texture areas such as one-pixel patterns. The algorithm first detects difficult texture regions. After the detection process is completed, the algorithm demosaicks the texture areas using special demosaicking operations whereas non-texture regions are restored using some of the existing demosaicking approaches. In this way, the quality of the texture areas in demosaicked images can be improved up to 70% while the computational complexity of the original demosaicking solution is increased only slightly.

The new algorithm is implemented as a core by using VHDL (Very High Speed Integrated Circuit Hardware Description Language) language. The operational verification of the VHDL implementation is performed on FPGA (Field Programmable Gate Array). The Virtex-II XC2V500 device is selected in the implementation. The core is capable of processing 1000x1000 pixels real-time digital video and 1000xn pixels digital still images. The system operates at 25 MHz frequency and can process 25 images per second which is a sufficient speed for video processing.