Nowadays more and more cameras that support higher and higer resolution are available to the consumer market at an affordable price. The question is, is it really always that useful to have a 12Mb jpeg image?

In linux you can downsize your pictures by reducing the image resolution and size automatically through the command line with the tools provided by ImageMagick program.

We are talking about mogrify comamnd.

after having installed imagemagick in Ubuntu and Debian through command

sudo apt-get install imagemagick

type

mogrify -resize 3000x3000 -verbose *.JPG

the extension is case sensitive according to the case of your files. You may also specify a singele file or a bunch of them according to the filename. * is a wildcard that means every/all

The resolution of 3000×3000 means that the images are going to have at most 3000px on the longest side. The other side of the picture will be resized accordingly and proportions will not be affected.

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