Convert Pdf to Png with Image Magick

This uses Image Magick (or ImageMagick)

convert -density 150 presentation.pdf -quality 90 output-%3d.jpg # all pages
convert -density 150 presentation.pdf[0] -quality 90 test.jpg # one page
convert -density 150 presentation.pdf[0] -quality 90 -resize 50% test.jpg

To force width, use resize and a height larger than needed, e.g. for A4 we can use a height twice the desired width (-resize will not stretch to fill, but resize until the image just fits in the box).

convert -density 300 inv1.pdf -resize 1920x3840 -quality 80 inv1-%02d.jpg

also

convert -density 300 inv1.pdf -resize 1920x3840 -background white -alpha remove -alpha off %d.png

Cygwin

Make sure you have ghostscript installed.

Security Error

If you get

attempt to perform an operation not allowed by the security policy `PDF'

then edit /etc/ImageMagic-6/policy.xml and find the line

    <policy domain="coder" rights="none" pattern="PDF" />

and change it to

    <policy domain="coder" rights="read|write" pattern="PDF" />