Monochrome option creates all white images

[oyvind.eide]

For some TIFF images, a convert such as:

convert -monochrome DSCF0002.tif test_ren.tif

gives a white-only output. The same happens with:

convert -threshold 0 -verbose DSCF0002.tif test_ren.tif

whereas this command gives a correct output:

convert -threshold 50% -verbose DSCF0002.tif test_ren.tif

So it looks like the auto-threshold does not work for this group of images. An example of such problem images may be found at:

http://folk.uio.no/oeide/DSCF0002.tif

Version info:

Solaris
Machine hardware: sun4u
OS version: 5.8
Processor type: sparc
Hardware: SUNW,Sun-Fire-880

> convert --version
Version: ImageMagick 6.2.9 09/15/06 Q16 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2006 ImageMagick Studio LLC


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Regards,

Øyvind Eide

[anthony]

-monocrome don't work for all images.
Look at IM Examples, Two Color Quantization
http://www.imagemagick.org/Usage/quantize/#colors_two
for a alternative technique.

PS: place the operator AFTER reading the image in, not BEFORE. Yes it works, but only for one operation. More than one will not be ordered correctly.

[oyvind.eide]

Thank you very much, the problem is solved.

No bug after all


Regards,

Øyvind Eide