Keywords : decoder
Al-Rafidain Engineering Journal (AREJ),
2012, Volume 20, Issue 3, Pages 117-127
Image compression is an important topic in commercial, industrial, and academic applications. Whether it be in commercial photography, industrial imaging, or video, digital pixel information can comprise considerably large amounts of data. Management of such data can involve significant overhead in computational complexity, storage, and time processing. This paper presents the implementation of a Modified JPEG CODEC algorithm for color images based on inter pixel redundancy. The modification uses the similarity of the adjacent pixels in blocks to omit complex calculation which AC components require in 2D-DCT unit. It applies quantize operation to one element instead of 64 coefficients and eliminates the zigzag unit. Finally , the entropy phase will process a smaller amount of data. In the decoder side the Laplacian parameter is estimated adding to a reduction in the accounts of blocks that have same neighbors pixels. The extensive experimental results demonstrate that the proposed approach can achieve best image quality. The Simulation results show that the Modified JPEG(MJPEG) algorithm can process a 512 X 512 color image in a reduced processing time ( more than 40%) compared to the original algorithm and by more resilience with higher compression ratio.
Keywords: JPEG; color image; encoder; decoder.