Re: Huffman and LZ or LZW coding


subrata.p@xxxxxxxxx wrote:

My images were binary images with .TIF extension, and when I put the
mouse pointer on an image it was showing in it's property that it has
G3 Fax compression. Anyway, the problem is a lot of images that I
tested were giving negative results. Is that OK?


Yes, you are compressing images that are already compressed. As it
happens, LZW not being the most efficient compressor, it is unable to
improve on the compression already in your TIF file.

If the assignment is to measure the compression of images, the best
thing to do is start with an uncompressed format that has little or no
header information, such as uncompressed windows BMP files.

|
| Mark Nelson - http://marknelson.us
|

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