ImageMagick's `convert` utility takes *too much* memory with PDF input
Solution 1:
I am using the following:
convert -limit memory 64 -limit map 128 original.djvu newfile.pdf
My main drive has limited space, so I prepend a variable
env MAGICK_TMPDIR=/host/Temp convert -limit memory 64 -limit map 128 original.djvu newfile.pdf
Solution 2:
Solved with the following:
cat <<EOF > /etc/profile.d/ImageMagick.sh
# Set ImageMagick memory limits: it eats too much
export MAGICK_MEMORY_LIMIT=1024 # Use up to *MB of memory before doing mmap
export MAGICK_MAP_LIMIT=1024 # Use up to *MB mmaps before caching to disk
export MAGICK_AREA_LIMIT=4096 # Use up to *MB disk space before failure
export MAGICK_FILES_LIMIT=1024 # Don't open more than *file handles
EOF
Solution 3:
Have you tried cache?
From the man page
-cache threshold
megabytes of memory available to the pixel cache.
Image pixels are stored in memory until 80 megabytes of
memory have been consumed. Subsequent pixel operations
are cached on disk. Operations to memory are significantly
faster but if your computer does not have a sufficient
amount of free memory you may want to adjust
this threshold value.