Legacy ImageMagick Discussions Archive

The reason for the inefficient compression ratio of CMYK images has been found and explained in the comments of the bug report at tiffinfo , and it is indeed something that should be fixed in ImageMagik, not tiffinfo. As a matter of fact, the issue, reason and potential solution was already hinted ...

contact the libtiff developers. Do you know how? The contact info for bug reports at libtiff.org refers to a mailing list whose interface returns 404 and a bugtracker whose domain does not even resolve. UPDATE: Duh… Apparently libtiff.org is not the official site for libtiff anymore. Wikipedia s ...

ImageMagick does not seem to efficiently compress TIFF CMYK images. Photoshop manages to Zip/LZW compress the same images to about 1/10 the size of what ImageMagick outputs. If I create an LZW-compressed RGB TIFF with ImageMagick of a full rainbow gradient: convert -size 8500x5000 \ -define gradient ...

`-colorspace sRGB` instead of `-colorspace RGB` did indeed fix it. Thanks!

I found that I can query if the composite PSD "is image fully-opaque?" with

I want to batch convert multiple PSD to a TIFF files without layers. If I am not mistaken, I can just grab the composite version of the PSD by appending [0] to its filename, but then, regarding the alpha, is there a way to programmatically keep it or discard it depending on whether there actually ...

When running any of the two example commands in Gradients in other Colorspaces to create a full rainbow gradient, convert -size 30x600 gradient:'#FFF-#0FF' -rotate 90 \ -set colorspace HSB -colorspace RGB \ gradient_rainbow_2.jpg the result is different depending on whether I output to JPEG or to ...

You need to include the geometry specifiers, the "+0+0" part, with the crop dimensions. ... -crop 520x256+0+0 ... Ouch! Indeed, works! I am using this version: $ convert --version Version: ImageMagick 6.9.5-5 Q16 x86_64 2016-08-07 http://www.imagemagick.org Copyright: Copyright (C) 1999-2016 ...

Works. Thanks!

convert "input.png" \ \( "input.png" -alpha extract \) \ -matte -bordercolor none -border 100x100 \ -alpha off -compose copy_opacity -composite -compose over \ \( -clone 0 -background black -shadow 25x4+3+4 \) \ +swap \ -background none -layers merge \ \( -alpha extract -colors 256 -alpha off ...

convert in.png -gravity Center -crop 512x512+0+0 +repage out.png I tried with an image 520×256 , but -gravity seems not to be doing anything: cropping starts from the left with both -gravity center and -gravity east , with the a first output being 520×256. Then it outputs an additional file p ...

the obvious way to do that is to extract the alpha, "-colors 256", and CopyOpacity it back to the image. Could you please rewrite my command above to include your suggested modification? I tried, but am not too sure would it should go (the alpha must be reduced to 8 bit after the generation of the ...

What version IM are you using? What Q-number, with or without HDRI? $ convert --version Version: ImageMagick 6.9.5-5 Q16 x86_64 2016-08-07 http://www.imagemagick.org Copyright: Copyright (C) 1999-2016 ImageMagick Studio LLC License: http://www.imagemagick.org/script/license.php Features: Cipher DPC ...

How can I crop an image to a maximum width × height (512×512), ideally also specifying -gravity center. If any of the image's dimension is lower than the specified size, it should be left as is. I.e:

600×600 → 512×512
200×600 → 200×512
600×200 → 512×200

The color that -trim cuts out seems to be of a higher color depth than the output's, and therefore leaves in colors that in the output will be the same as the corner pixels onced rounded down to the output's color depth. How do I reduce the bit depth of ImageMagick's buffer so that -trim works based ...