Image magicks are free software suite for the creation, modification, and display of bitmaps images. Belows are some shortcut how to resize many images just in a wink.
open your favourite terminal, then do this magick command:
user@machine> sudo apt-get install imagemagick
Go to your folder location where your images placed.
user@machine> cd (go to your location)
Now let’s start the magick command to batch resize all images in your folder using mogrify. Mogrify is a member of imagemagick package.
user@machine> mogrify -resize 800x600 "*" *.png
Sim Sala Bim !!!. The above example will resize all of your images which have png extension to 800×600 px resolution, just simply configure the option to your needs.
Congrats, now your upload progress bar can running faster than before !