2006.03.04 03:12 "Re: [Tiff] LZW Compression with 16-bit TIFF", by Bob Friesenhahn
On Fri, 3 Mar 2006, Frank Peters wrote:
With 16-bit tiff files, however, the compressed file is actually LARGER. For example, using the above command a 36 megabyte 16-bit tiff file will "compress" to about 46 megabytes. For the other possible options, "-c lzw:1" and "-c lzw", the results are essentially the same. The compressed file is always significantly larger.
If I use "-c zip" as the option, 16-bit files are reduced somewhat (from 36 Mb to 34 Mb).
Is there possibly a bug in the 16-bit lzw code or does the fault lie elsewere?
16 bit data can be difficult to compress. Have you tried enabling horizontal differencing?
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