2004.01.23 20:12 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Chris Cox
Frank Warmerdam wrote:
>"sample" == "band" == "channel" == "component" ==?
Thanks Frank. Now I know I finally did understand it correctly. Am I also
correct in thinking that the only proper way ignorant software (as in
>>software that doesn't know about how the image came about or what it is
intended to contain) can correctly interpret this 3-channel image as a
>grayscale image with 2 extra channels that have no specified
application/meaning? If ignorant software were to have to render this image,
the correct thing to do is to render the first channel as grayscale, and
>>discard the others as far as rendering is concerned, is that right? I
realize this may also be trivial questions, but this thread is very
I am by no means an authority on the TIFF specification. My interpretation of the file in question is that a sensible application should render the first band in greyscale and ignore the 2nd and 3rd since they are extra samples with no meaning attached.
Or load the 2nd and 3rd channels as alpha (not transparency) channels -- as Photoshop does.
It would be incorrect to interpret this image as RGB.