2009.01.13 21:56 "Re: [Tiff] Libtiff compression ratios", by Toby Thain

On 13-Jan-09, at 4:01 PM, Nick wrote:

Setting TIFFTAG_PREDICTOR to PREDICTOR_HORIZONTAL worked beautifully. With the predictor running, libtiff's compression ratios reach parity with Photoshop.

Increasing the deflate compression ratio to its maximum via TIFFTAG_ZIPQUALITY had only marginal effects on compression (a 2% improvement) while tripling the computation time required.

I appreciate the advice! Perhaps PREDICTOR_HORIZONTAL might make a good default value for the libtiff predictor tag?

It would restrict compatibility to those readers that implement the predictor.

--Toby

> Nick
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