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2006.12.05 15:52 "[Tiff] Grayscale, or is it?", by Joris Van Damme
2006.12.05 17:18 "Re: [Tiff] Grayscale, or is it?", by Bob Friesenhahn
2006.12.05 17:34 "Re: [Tiff] Grayscale, or is it?", by Joris Van Damme
2006.12.05 17:45 "Re: [Tiff] Grayscale, or is it?", by Bob Friesenhahn
2006.12.05 18:44 "Re: [Tiff] Grayscale, or is it?", by Joris Van Damme
2006.12.05 22:10 "Re: [Tiff] Grayscale, or is it?", by Frank Warmerdam
2006.12.05 20:37 "Re: [Tiff] Grayscale, or is it?", by Joris Van Damme
2006.12.05 21:16 "Re: [Tiff] Grayscale, or is it?", by Edward Lam
2006.12.05 21:30 "Re: [Tiff] Grayscale, or is it?", by Joris Van Damme
2006.12.05 22:28 "Re: [Tiff] Grayscale, or is it?", by Edward Lam
2006.12.05 22:41 "Re[2]: [Tiff] Grayscale, or is it?", by Jean-Yves Le Ridant
2006.12.05 23:13 "Re[2]: [Tiff] Grayscale, or is it?", by Bob Friesenhahn
2006.12.05 23:29 "Re: [Tiff] Grayscale, or is it?", by Phillip Crews
2006.12.06 02:05 "Re: [Tiff] Grayscale, or is it?", by Graeme Gill
2006.12.05 22:56 "[Tiff] Re: Tiff Digest, Vol 31, Issue 3", by Glenn Widener
2006.12.05 23:26 "Re: [Tiff] Re: Tiff Digest, Vol 31, Issue 3", by Toby Thain
2006.12.06 01:58 "Re: [Tiff] Re: Tiff Digest, Vol 31, Issue 3", by Graeme Gill
2006.12.06 04:45 "Re: [Tiff] Re: Tiff Digest, Vol 31, Issue 3", by Edward Lam
2006.12.06 20:56 "Re: [Tiff] Re: Tiff Digest, Vol 31, Issue 3", by Joris Van Damme
2006.12.06 22:19 "Re: [Tiff] Re: Tiff Digest, Vol 31, Issue 3", by Graeme Gill
2006.12.06 23:30 "Re: [Tiff] Re: Tiff Digest, Vol 31, Issue 3", by Joris Van Damme
2006.12.07 01:28 "Re: [Tiff] Re: Tiff Digest, Vol 31, Issue 3", by Graeme Gill
2006.12.07 07:45 "Re: [Tiff] Re: Tiff Digest, Vol 31, Issue 3", by Joris Van Damme
2006.12.06 20:56 "[Tiff] Re: Grayscale, or is it?", by Joris Van Damme
2006.12.06 21:57 "Re: [Tiff] Grayscale, or is it?", by Graeme Gill

2006.12.05 21:30 "Re: [Tiff] Grayscale, or is it?", by Joris Van Damme

Edward,

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?

Best regards,

Joris Van Damme
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