[Gdal-dev] Advice on Raster Formats

[Andrey Kiselev]

On Tue, Aug 30, 2005 at 04:51:37PM -0400, Bill Binko wrote:
> > > I *think* you would have to translate your tiff files first to
> > > compressed  tiff using the -co option.
> > > 
> > > COMPRESS=[JPEG/LZW/PACKBITS/DEFLATE/NONE]
> 
> I don't have LZW enabled (gives a Unisys patent notice), but on deflate, 
> the PREDICTOR=2 saved about 2% over no predictor value, and PREDICTOR=3 
> threw an error.

That means you have outdated libtiff. Unisys patent has been expired, so
you can safely use LZW. And, as I noted in previous message, you need
libtiff 3.7.3 to utilize predictor 3. And do not forget that this type
of predictor should be used with the floating point data only and
useless in other cases.

In general, deflate method compresses better than LZW, but LZW works
faster.

Regards,
Andrey

-- 
Andrey V. Kiselev
Home phone:  +7 812 5970603  ICQ# 26871517