2006.12.05 21:30 "Re: [Tiff] Grayscale, or is it?", by Joris Van Damme
So that's three out of three in favor of option 1), and confirming option 1) is common practice.
For the record, I don't use LibTiff's RGBA interface (ie. use TIFFReadEncodedStrip() or TIFFReadEncodedTile() instead) so I should probably abstain from voting. :)
None of your previous comments were public, so I didn't actually include you in the count. I did include myself, hence that number three, even though I used to prefer option 3) before, because I got convinced option 3) has little basis.
Nonetheless... You don't need to use LibTiff's RGBA interface to explicitely or implicitely have an opinion. Just answer this question: when you read 8bit MinIsBlack greyscale (Photometric 1, otherwise known as BlackIsZero and PHOTOMETRIC_MINISBLACK) from TIFF, in order to display on a normal sRGB monitor, do you do any non-lineair conversion in between decoding and display, or do you just set the R, G, and B values directly with the greyscale values as read from the TIFF file?
Joris Van Damme
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