imagemagick, imagemagick-6-doc:

• convert: convert image format and other transforms
  • convert img.jpg img.png
  • convert xx*.png -append example.png
• mogrify: similar to convert but modifies the same image in place
  • mogrify -resize 480x pic.jpg

Articles tagged with image on SysAdminTools:

2019-07-30: XFig Diagramming Tool
2019-07-20: Removing Image Metadata