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2005.09.12 17:12 "[Tiff] extracting 16-bit grayscale from photoshop", by Hoan Chau
2005.09.12 19:12 "Re: [Tiff] extracting 16-bit grayscale from photoshop", by Chris Cox
2005.09.12 19:38 "Re: [Tiff] extracting 16-bit grayscale from photoshop", by Joris

2005.09.12 17:12 "[Tiff] extracting 16-bit grayscale from photoshop", by Hoan Chau

I have a 16-bit grayscale image that when read by TiffReadScanline identifies the first byte for the first pixel as 0x14 = 20; and the second byte as 0x5e = 94. Compared to another program called PolyView (just to check my sanity), the first byte is indeed a value of 20. However, when i go to view the image in Photoshop, I have completely different information displayed: pixel value = 29 = r = g = b. Furthermore, if I view it as a 16-bit value it is 3,726.

Thus, I don't understand how the data can be interpreted one way in Photoshop and in another way by TiffReadScanline.

Is there a tag/mask that Photoshop uses which converts each two bytes per pixel to its 16-bit value (e.g. 0x145e to 3,726)?

Hoan