Lossless Image Compression And Dsp

The purpose of lossless image compression is to reduce the amount of data used to represent the image without any information loss, so the original image can be recovered correctly when decodeing. It's mainly applied in some applications where the images are subjected to further processing, repeated compression/decompression, high cost of the image acquiring, the desired quality of the rendered image is yet unknown. But the general compression methods haven't achieved the best compression result, therefore developing a real time compression method based DSPs are of significant practical and commercial interest.Lossless image compression based on integer wavelet transform and it's implementation along with optimization is discussed in this paper. The main work is:1. The process of development of image coding technology is reviewed, the basic coding technique and some international standards in this field is summarized.2. A integer to integer wavelet transform is constructed based lifting scheme, and then the typical embedded wavelet coefficient coding methods including EZW, SPIHT are discussed subsequently.3. The software development on TMS320DM642 is studied. A multitask system framework based on DSP/BIOS and RF5 is designed, the image capture driver module and TCP/IP network module along with system boot module are also designed according to the hardware.4. The improvement and it's simulation on hardware of this algorithm. A modified blocking lifting wavelet algorithm is proposed, which eliminates CACHE misses mostly and solves the problem of low efficiency in DSP, the efficiency was raised significantly after optimizations. The combination of NLS and arithmetic coding is designed for the problem of low speed and compression ratio in coefficient coding of small ones, the new method reduced compress time and improved compression ratio on the premise of keeping it's embedded stream property.