This is a very quick script to resize all files of type jpg to 1024×1024 (longest edge becomes 1024 pixels) and name them “1024-originalfile name.jpg” using ImageMagick for Windows

Open a command prompt and cd into the folder containing your jpg’s and run the following.

for /f "usebackq delims=" %x in (`dir /b *.jpg`) do convert "%x" -resize 1024x1024 "1024-%x"