2005.11.02 16:58 "[Tiff] Writing bilevel and transparent TIFFs efficiently", by Rupali Holmes

2005.11.03 17:06 "Re: [Tiff] Writing bilevel and transparent TIFFs efficiently", by Frank Warmerdam

On 11/3/05, Bob Friesenhahn <bfriesen@simple.dallas.tx.us> wrote:

Ultimately, the PHOTOMETRIC_RGB photometric with associated alpha at 8 bits per sample is the best supported by readers even though it is not very efficient.

Bob / Rupali,

It seems to me that with a suitable compression format (Deflate or LZW) the RGBA data form should compress very well if there are only two 32bit values ever used.

As Bob notes this would likely be the most portable way of transporting a color image with transparency.

Best regards,

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