Legacy ImageMagick Discussions Archive

I would like replace the color of the background, based on the color of pixel 10,10, to tranpsarency.

I managed the get the color of pixel 10, 10 by issueing:

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convert logo: -format %[pixel:p{10,10}] info:
white

I also manage to replace the white in the logo to transparency by:

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convert logo: -transparent white logo.png

However, somehow the combination does not work. What am I doing wrong?
Both on Windows and Mac I can not get it to work.
I tried with and without quotes ...

convert logo: -transparent %[pixel:p{10,10}] logo.png
convert.exe: unrecognized color `%[pixel:p{10,10}]' @ warning/color.c/GetColorCompliance/1045.

convert logo: -transparent "%[pixel:p{10,10}]" logo.png
convert.exe: unrecognized color `%[pixel:p{10,10}]' @ warning/color.c/GetColorCompliance/1045.

convert -version
Version: ImageMagick 6.8.8-10 Q16 x86 2014-03-25 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2014 ImageMagick Studio LLC
Features: DPC OpenMP
Delegates: bzlib cairo freetype jbig jng jp2 jpeg lcms lqr pangocairo png ps rsvg tiff webp xml zlib

"white" is a colour constant. "%[pixel:p{10,10}]" is a colour expression. In v6, "-transparent" needs a colour constant.

EDIT: I should add, in v7 "magick", you can use that colour expression:

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magick logo: -transparent "%[pixel:p{10,10}]" logo.png

Legacy ImageMagick Discussions Archive

Convert %[pixel:p{10,10}] to transparent

Convert %[pixel:p{10,10}] to transparent

Re: Convert %[pixel:p{10,10}] to transparent