2004.05.18 17:58 "Re: [Tiff] Compression", by Andrey Kiselev

Efficiency of compression is depend on the nature of your data. In general LZW works better than Packbits and Deflate works better than LZW

So your question does not make sense without data description (in terms of size, type and contents).

Thanks for your answer. In fact my main concern is to understand why I have no gain when changing the compression scheme. (is it because I m writing line by line ?)

And I m wondering if I ll have better result if I don t write line by line (if possible).

Line by line writing results in stripped image. Tiled images sometimes compresses better than tiled. Size of tiles/stripes has matter too and best size differs for different algorithms.

I'm recommend you to experiment with the tiffcp utility: it is possible to probe various compression schemes and image organizations and pick up the best parameters for your data.

Andrey

Andrey V. Kiselev
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