2005.05.02 19:11 "Re: [Tiff] Color TIFF/JPEG compression questions", by Andrey Kiselev

Joris,

We should check that we are talking about the exact same quad-jpeg.tif.

quad-jpeg.tif does not contain the YCbCRSubsampling tag, but the one created with tiff2rgba does.

I know for a fact that AsTiffTagViewer shows exactly what is there, and, unlike LibTiff, that stuff isn't burdoned with an actual image decoder part and a subsampling-fixup scheme and such...

That is the way how tiffdump works.

So if AsTiffTagViewer doesn't mention the tag, and tiffinfo does, I know for a fact that tiffinfo must be wrong.

tiffdump shows the TIFF structures how they will be visible for a top level application. Subsampling fixing logic works here, so we can see the tag which is not set in the original TIFF file.

Regards,
Andrey

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