Read 32bit bmp weird

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dlemstra
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Re: Read 32bit bmp weird

Post by dlemstra »

I will take a look at the BMP when I am back behind a pc again. There might be a something that should tell us to ignore the extra bits. I cannot find the link I found earlier when I researched this but zero is transparent and 255 opaque.
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wizard29
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Re: Read 32bit bmp weird

Post by wizard29 »

I found some interesting facts about the problem. Maybe it would be helpful.
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dlemstra
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Re: Read 32bit bmp weird

Post by dlemstra »

It seems like they are writing BMP3 files but I cannot test that at this moment. I think our code should not enable the alpha channel if the bmp header version is lower then 4. I will work on a patch to test this next week.
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fmw42
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Re: Read 32bit bmp weird

Post by fmw42 »

See http://www.imagemagick.org/Usage/formats/#bmp. It appears that BMP3: does not support transparency (at least not that IM can do).
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dlemstra
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Re: Read 32bit bmp weird

Post by dlemstra »

This is fixed and will work properly in the next release of ImageMagick (6.9.0-1)
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