weird png file

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squ
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weird png file

Post by squ »

convert makes this image dark, is this a 'convert' problem or something wrong is with the image ?
Image
for example, after

Code: Select all

convert file.png -resize 100% out.png

resulting image is:
Image
snibgo
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Re: weird png file

Post by snibgo »

It doesn't go darker for me, IM 6.7.9 or 6.8.3, on Windows 7. If you have an older version, try an upgrade.
snibgo's IM pages: im.snibgo.com
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fmw42
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Re: weird png file

Post by fmw42 »

What version of IM are you using? It may be that you were in the transition time when IM was changing to conform to sRGB and linear RGB and grayscale standards. See viewtopic.php?f=4&t=21269

It started about IM 6.7.6.7 and probably was not fully complete until 6.7.8.3.
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glennrp
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Re: weird png file

Post by glennrp »

If you build IM with libpng-1.6.0, which identifies and checks sRGB ICC profiles, you get this warning with your input file:
identify: iCCP: known incorrect sRGB profile `remtext-arr_zps047ada59.png' @ warning/png.c/MagickPNGWarningHandler/1787.
squ
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Re: weird png file

Post by squ »

Code: Select all

$ convert -version
Version: ImageMagick 6.8.0-7 2013-03-01 Q16 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2012 ImageMagick Studio LLC
Features: OpenCL
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fmw42
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Re: weird png file

Post by fmw42 »

Your conversion works fine for me using IM 6.8.3.7 Q16 Mac OSX Snow Leopard using libpng 1.4.11
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