Splitting pages and other scanned document tricks
Posted: Wed Dec 09, 2015 1:34 pm
I'm keeping some notes here for future reference when processing scanned files.
I found the following command useful for taking a bunch of image files scanned 2-up and rotating 90 degress, then splitting the 2-up scan into separate pages (down the middle) and combining into a single PDF:
convert -verbose *tiff -rotate 90 -crop 2x1@ +repage output.pdf
"convert" is part of the ImageMagick suite of command-line image manipulation tools.
Any further image manipulation tricks welcome in thread, especially if you know how to get imageMagick to convert PDF to TIFF without ruining the image quality. I know that ImageMagick used Ghostscript (gs) to convert from PDF to bitmap, but somehow the image quality is horrible. It must be in the way ImageMagic is invoking gs, since Ghostscript is certainly capable of high-quality output.
I found the following command useful for taking a bunch of image files scanned 2-up and rotating 90 degress, then splitting the 2-up scan into separate pages (down the middle) and combining into a single PDF:
convert -verbose *tiff -rotate 90 -crop 2x1@ +repage output.pdf
"convert" is part of the ImageMagick suite of command-line image manipulation tools.
Any further image manipulation tricks welcome in thread, especially if you know how to get imageMagick to convert PDF to TIFF without ruining the image quality. I know that ImageMagick used Ghostscript (gs) to convert from PDF to bitmap, but somehow the image quality is horrible. It must be in the way ImageMagic is invoking gs, since Ghostscript is certainly capable of high-quality output.