[Octave-bug-tracker] [bug #47746] imwrite writes incorrect TIFF pixel values from uint8 array on i686-linux-gnu

[Mike Miller]

Follow-up Comment #8, bug #47746 (project octave):

Attaching the standalone C++ program I wrote to emulate what I think Octave is
doing.

In Octave running in gdb, I get the following (at __magick_read__.cc line
1215):


(gdb) p pix[1]
$6 = {blue = 256, green = 256, red = 256, opacity = 65278}
(gdb) p pix[2]
$7 = {blue = 513, green = 513, red = 513, opacity = 65021}


These are off by 1, but should still evaluate to 8-bit pixel values of 1, 2,
etc. I even added a round when constructing the Color, values went up by 1
(257, 514, etc) but the image file is still incorrect.

(file #37121)
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Additional Item Attachment:

File name: gmtest.cc                      Size:0 KB


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