I need to quickly convert odfs to image for both online processing and one off processing. Luckily imagemagick had me covered for both.
First install imagemagick:
sudo apt-get install imagemagick
Then use the convert function to do the work:
convert example.pdf example.png
This will append ## to the file name if the pdf is multiple pages. convert also has a few options that effect the quality, size, trimming, etc.