Transform any image to WebP from the terminal

Author

Affiliation

Dylan Castillo

Iwana Labs

I was annoyed by the file size of my photo in the About page, because it was slowing down the page load.

Is it important? No.

Don’t I have better things to do on a Saturday afternoon? Yes.

But it’s like going to bed with the closet door open—you know there’s nothing in there, but you just can’t shake the feeling that the devil (or Diosdado Cabello) might jump out and kill you in your sleep unless you get up and shut it.

So I got o1-mini to write a simple script for me, and thought others might find it useful.

Here it is:

function img2webp() {

  # Check if the input file is provided or if help is requested
  if [[ $# -lt 1 || "$1" == "--help" || "$1" == "-h" ]]; then
    echo "Usage: img2webp input_image [quality]"
    echo "  input_image: Path to the input image file"
    echo "  quality: Quality of the output WebP image (0-100, default is 80)"
    return 1
  fi

  local input="$1"
  local quality="${2:-80}"  # Default quality is 80 if not specified
  local output="${input%.*}.webp"

  # Convert the image to WebP using ffmpeg
  ffmpeg -i "$input" -qscale:v "$quality" "$output"

  # Check if the conversion was successful
  if [[ $? -eq 0 ]]; then
    echo "Successfully converted '$input' to '$output' with quality $quality."
  else
    echo "Failed to convert '$input' to WebP."
    return 1
  fi
}

If you’re using MacOS, you first need to install ffmpeg using Homebrew:

brew install ffmpeg

Then you can add it to your .zshrc and use it by running img2webp <path_to_image> [quality].

Just as reference, keeping the same quality, I decreased my profile picture from 234KB to 36KB by just changing from PNG to WebP.

Hope you found this useful.