I have a colour PDF file, and I'm going to print it out and then photocopy it in black and white. I'd like to know what it's like in B&W before photocopying it. Is it possible to 'greyscale' a PDF on the command line using free software? I'm using Ubuntu 9.10.
ImageMagick can do this.
convert -colorspace GRAY color.pdf gray.pdf
via this email
gs \ -sOutputFile=output.pdf \ -sDEVICE=pdfwrite \ -sColorConversionStrategy=Gray \ -dProcessColorModel=/DeviceGray \ -dCompatibilityLevel=1.4 \ -dNOPAUSE \ -dBATCH \ input.pdf
Here’s a little script which in addition to the grayscale conversion can concatenate multiple input files. To use the script, put the following lines in a file, e.g. "convert2gray.sh"
#!/bin/bash gs -sOutputFile=converted.pdf -sDEVICE=pdfwrite -sColorConversionStrategy=Gray -dProcessColorModel=/DeviceGray -dCompatibiltyLevel=1.4 -dNOPAUSE -dBATCH $@
and make it executable
chmod +x convert2gray.sh
./convert2gray.sh input1.pdf input2.pdf … lastinput.pdf
will produce a single PDF "converted.pdf", which contains all pages from the input files converted to grayscale.
I had to print out mutliple files all in grayscale and found this the easiest way, since you can print out everything after inpection with one command.