2008.02.11 07:43 "[Tiff] TIFFReadRGBAImage rendering upside-down", by Mick O'Neill

2008.02.11 16:38 "[Tiff] Re: Help with TIFFWriteScanline()", by James Sumners

How about I keep answering my own questions? Does that work for everyone :)

I see that I was confusing BitsPerSample with SamplesPerPixel. If I understand this correctly, 2 SPP would mean it takes 2 "pixels" to represent 1 pixel at 1 SPP? And BitsPerSample is the integer value limit for each sample?

On Feb 11, 2008 11:33 AM, James Sumners <james.sumners@gmail.com> wrote:

After browsing the mailing list archives I found out about the tiffinfo tool. tiffinfo reported that my original image had a SamplesPerPixel of 1. For some reason, unbeknownst to me, my program is getting a value of 0 for SamplesPerPixel from the original image. So I manually set the value to 8, because that is what I understand the specification to be (8 or 16 SPP for grayscale/color and 1 SPP for bilevel). After changing my manual SPP value from 8 to 1 the copied image is written correctly.

This is the first time I've done any graphics programming. So I'm sure that I am not understanding something. Would someone please explain this situation to me? Would 8 SPP squeeze the image into a smaller space? How is 1 SPP producing a grayscale image?

James Sumners

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