How to resize photos through she'll?

Question

bash

Hello
There is a \images\ folder, there are a lot of photos with a guid name and .jpg format in the folder
Question - how to compress all photos so that the size of the photo decreases by at least % 30?

Answer 1

Use the imagemagick utility.
And then read MAN.
We change the quality
We change the sizes
And many other goodies)
You can write a batch processing script!

Answer 2

We go to the directory where the necessary photos are located and execute the command:

mkdir new; for f in *.jpg ; do convert -resize 840x460 "$f" "new/${f%.jpg}.jpg" ; done