ImageMagick (convert) tool could be used for different image manipulation tasks. Here I will mention some of them I have used it for.
Get verbose information about image
# convert some_test_image.jpg -verbose info:
Change JPEG image quality
# convert original_image.jpg -quality 50 new_image_with_50_quality.jpg
Convert/Resize image to 1600×1600 to fit ebay requirements
I need this conversion in order my images to fit the Ebay image size limits, which are also 1600×1600 pixels. Here is the the deal:
convert IMAGE_ORIG.jpeg -resize 1600×1600 IMAGE_RESIZED.jpeg