Imagemagick

1. Converting all files to jpg

In a folder, convert all png, webp, gif files to jpg.

magick mogrify -format jpg *.png
magick mogrify -format jpg *.webp
magick mogrify -format jpg *.gif

2. File renaming

In Powershell, this will rename all jpeg to jpg.

dir *.jpeg | rename-item -newname { [io.path]::ChangeExtension($_.name, "jpg") }

3. Resizing all jpg files

This command "Shrinks an image with dimension(s) larger than the corresponding width and/or height argument(s)."

magick mogrify -resize '720x720>' *.jpg

Others

These are other commands that may be useful.

magick mogrify -resize 960x528 *.jpg

This command resizes all of the .png files in your directory to a size of 960 pixels by 528 pixels. Perhaps the height isn’t as important as the width. You can simply enter:

magick mogrify -resize 960 *.jpg

This will scale all of your images to a width of 960 pixels, the height will be scaled accordingly, preserving the aspect ratio.

This command will optimize all jpg images to Google Pagespeed recommendations.

magick mogrify -sampling-factor 4:2:0 -strip -quality 85 -interlace JPEG -colorspace sRGB *.jpg