Without modifying the source of GraphicsMagick itself, you can’t. The gm module interacts with the GraphicsMagick program through the command line. The arguments you’re passing through the .in() method are being converted into command-line arguments. The GraphicsMagick program only accepts filenames for this argument and will not attempt to process any direct form of data. … Read more
Finally I find THE solution: convert in.pdf -append out%d.png Thanks to this post. edit As a plus, the opposite operation is: convert *.png output.pdf or if you have foo1.png, foo2.png..fooN.png convert foo?.png output.pdf Notice that does not work with foo01.png, foo02.png..foo0N.png
ImageMagick can do it, although it’s a bit convoluted. One way is: convert img1 img2 -fx “(((255*u)&(255*(1-v)))|((255*(1-u))&(255*v)))/255” img_out (img1,img2,img_out are the two input and single output file names respectively). Explanation It’s a bit ugly (I’m sure someone with more ImageMagick-fu than me could clean it up but it works like this: -fx “xxx” basically says … Read more
You can batch convert HEIC to jpg with the following, but you’ll lose quality: mogrify -format jpg *.HEIC
You can use one commandline with two commands (gs, convert) connected through a pipe, if the first command can write its output to stdout, and if the second one can read its input from stdin. Luckily, gs can write to stdout (… -o %stdout …). Luckily, convert can read from stdin (convert -background transparent – … Read more
You can further reduce quality of PNG by using posterization: https://github.com/pornel/mediancut-posterizer (Mac GUI) This is a lossy operation that allows zlib to compress better. Convert image to PNG8 using pngquant. It reduces images to 256 colors, so quality depends on the type of image, but pngquant makes very good palettes, so you might be surprised … Read more
The problem is that your source PNGs have an alpha channel which is not supported by GIFs. So you have to remove transparency from your source images first. Since you’re dealing with multiple source images, you can’t use the -flatten method. With newer ImageMagick versions the following should work: convert -background white -alpha remove -layers … Read more
sdaau, the command you used for trying to convert your PDF to CMYK was not correct. Try this one instead: gs \ -o test-cmyk.pdf \ -sDEVICE=pdfwrite \ -sProcessColorModel=DeviceCMYK \ -sColorConversionStrategy=CMYK \ -sColorConversionStrategyForImages=CMYK \ test.pdf Update If color conversion does not work as desired and if you see a message like “Unable to convert color space … Read more
After another half hour of searching I have stumbled upon the overly simple answer. The following will resize an image with the exact dimensions given: mogrify input.png -resize 256×256! output.png If you want to read more about it, I got the answer from this link: https://superuser.com/questions/212752/how-to-stretch-an-image-in-one-dimension
I just managed to tell ImageMagick about the fonts on my OSX system like this: # Make a new directory for ImageMagick local settings and cd into it mkdir ~/.magick cd ~/.magick # Grab script to find all fonts on system and store them in a config file curl -L http://www.imagemagick.org/Usage/scripts/imagick_type_gen > type_gen # Run … Read more