Is it possible to combine, lossy and lossless image compression???

Sir, is it possible to combine lossy and lossless compression together,, for eg, I've a brain MRI image (tumor) , i segmented as ROI and non ROI , so now, i've to compress ROI with lossless, and non ROI with lossy compression and to combine both.... so far i segmented the roi and non-roi separately,.. with salience i separated compressed roi, but how to combine both??? thanks in advance..

[Radhika UD]

Hi..I am in need of same type of compression now.. Please share for any solutions.. Thanks..

Answer 1

[Image Analyst]

I wasn't sure that was legal, but maybe times are changing. See this 2006 paper that proposes a method exactly as you described: http://www.vast.uccs.edu/~tboult/PAPERS/IJBRA-06-Zukowski-Boult-Medical-Image-Compression.pdf

[Subha]

Sure sir will see to it..

Answer 2

[Walter Roberson]

For example you can take

data_in_ROI = YourData(ROI_mask);
data_outside_ROI = YourData(~ROI_mask);
compressed_mask = run_length_encode_bitwise(ROI_mask);
compressed_inside = lossless_compression(data_in_ROI);
compressed_outside = lossy_compression(data_outside_ROI);
compressed_result = [compressed_mask, compressed_inside, compressed_outside];

Restoration would be decoding the compressed result to separate the parts, then uncompressing the mask, uncompressing the losslessly-compressed inside data, storing it in the positions where the mask is true, uncompressing the lossy outside data, storing that in the positions where the mask is false.