For vector graphics, ImageMagick has both a render resolution and an output size that are independent of each other.
Try something like
convert -density 300 image.eps -resize 1024x1024 image.jpg
Which will render your eps at 300dpi. If 300 * width > 1024, then it will be sharp. If you render it too high though, you waste a lot of memory drawing a really high-res graphic only to down sample it again. I don't currently know of a good way to render it at the "right" resolution in one IM command.
The order of the arguments matters! The -density X
argument needs to go before image.eps
because you want to affect the resolution that the input file is rendered at.
This is not super obvious in the manpage for convert
, but is hinted at:
SYNOPSIS
convert [input-option] input-file [output-option] output-file