This can be done for free using bash and ghostscript, or even using the free tools from ImageMagick (like convert). But there are decent third-party proprietary

This can be done for free using bash and ghostscript, or even using the free tools from ImageMagick (like convert). But there are decent third-party proprietary solutions, such as the Enfocus PitStop Pro suite of softwares. Don't use Adobe products, please.