Legacy ImageMagick Discussions Archive

Thanks, fmw42 -- I'll keep that in mind!

truecoloralpha does work in a way but it still generates an empty alpha channel for images with no alpha channels and I prefer it wouldn't do that. It's Ok for now though -- I have a non-IM related solution.
(btw., I don't believe that truecoloralpha is mentioned in command line options reference)

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A very interesting suggestion regarding JP2 and Photoshop seems to be opening it correctly.
Unfortunately, I'm constrained by the formats which are supported by Unity3D and it currently doesn't have a support for JP2.

Thanks, snibgo. At first, I thought it might be the libtiff trouble but it turns out to be something entirely different. I spent many hours just to find out that the Photoshop indeed doesn't support JPEG-compressed TIFF containing alpha channels . The problem is that it won't notify you about the in...

It didn't work with Q16 either. Q8, Q16, Dynamic, Static, Win32 -- they all produce corrupt alpha. Oddly XnView doesn't see the image as corrupted but I don't trust XnView anymore. And Photoshop shows the image as corrupted. I was under the impression that IM install has everything that is required....

Version: ImageMagick 7.0.8-0 Q8 x64 2018-06-12 http://www.imagemagick.org Copyright: Copyright (C) 1999-2018 ImageMagick Studio LLC License: http://www.imagemagick.org/script/license.php Visual C++: 180040629 Features: Cipher DPC Modules OpenMP Delegates (built-in): bzlib cairo flif freetype gslib ...

Compressing TIFF images containing alpha channel using JPG compression will randomly produce corrupt images. The very same images without alpha channels will produce the correct output. Source TIF image: https://www.dropbox.com/s/3kehra55qw8308q/rgba.tif?dl=0 Screenshot of the compressed source imag...

Thank you very much! It looks like -type truecolor does work. True, it discards alpha channel completely and using -type truecolormatte does just the opposite by forcing an alpha channel in images which don't have one initially but it's good solution for now. I'm still not happy about IM converting ...

Thanks, fmw42 , and snigbo . I actually did find the same solutions before posting but they didn't quite work or so I thought. I gave it another try and here's what I found: When converting an RGBA image containing non-grayscale color values everything works as expected (i.e. alpha un/association wo...

Hello, everyone. It seems that ImageMagick turns a regular alpha channel into an associated alpha channel if a converted image has only grayscale color values despite being an RGB image. How to force the conversion process not to change the output color space and most importantly keep an alpha chann...