How do I find large files on the command line under Linux?

With the command “find” not only files can be found by their name, but also by other characteristics:

# Find all ".jpg" files larger than 1 megabyte
find ./foldername -name "*.jpg" -size +1M

This command finds all files in a directory and its subdirectories, which are are larger than 1 megabyte.

How can I resize large image files?

Most Linux systems have ImageMagick already installed. If not,

sudo apt install imagemagick

will install it (if we have a system with apt support). The following command resizes a file to a maximum edge length (1200px in the example):

convert -resize "1200>" test.jpg

Combining both results in:

find ./foldername -name "*.jpg" -size +1M | xargs convert -resize "1200>"