2006.09.26 05:43 "Re: [Tiff] Tiffcrop beta available for testing", by Joris Van Damme

This applies to all forms of subsampled YCbCr, uncompressed, LZW compressed, flate compressed, whatever. Unfortunately, the LibJpeg library returns another

> organisation, and a convertion needs to be made...

I meant, a convertion needs to be made inside tif_jpeg.c, that may not have been clear. The purpose of this conversion is to take data organisation as returned by LibJpeg, and reformat it into the compression-independent organisation that is assumed by the rest of the library, thus making all subsampled YCbCr organisation uniform.

I think there's currently a bug left in exactly this part of tif_jpeg.c, presumably, seeing the output of some image, but I've not yet had the time to investigate properly. This may additionally make it hard for Richard to add subsampled YCbCr support inside tiffcrop, unless he chooses to work from uncompressed subsampled YCbCr testimages and drops the use of JPEGCOLORMODE_RGB if he's using it right now, which I'd recommend anyway since that is the single shortest path to full compression-independent support for subsampled YCbCr.

Best regards,

Joris Van Damme
info@awaresystems.be
http://www.awaresystems.be/
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