Wordpress Image Resizer / Optimizer

With wordpress there are a lot of plugins for optimizing previously uploaded images. Interestingly, almost all plugins direct you to use their own APIs for this task and charge high fees for this simple task. Whereas on our own server we can do it very simply. The image optimization function below will probably do the trick. I would base it on the ubuntu operating system, but you can easily find related packages for other operating systems.

Installation

Install required packages:

sudo apt install imagemagick pngquant

Add image optimizer method to .bashrc:

# WARNING: The method below will overwrite the same file.  
# If you want it to write a different file, you need to update the code accordingly.

function optimizeImage {
    imagePath=$1
    maxWidth=$2
    maxHeight=$3
    quality=$4
    filename=$(basename -- "$imagePath")
    directory=$(dirname -- "$imagePath")
    extension="${filename##*.}"
    filename="${filename%.*}"

    echo "Processing $imagePath"

    if [ "$extension" == "png" ]; then
        convert ${imagePath} -resize ${maxWidth}x${maxHeight} ${imagePath}
        pngquant ${imagePath} --force --quality=${quality} -o ${imagePath}
    else
        convert ${imagePath} -resize ${maxWidth}x${maxHeight} -quality ${quality} ${imagePath}
    fi
    
    echo "Done"
}

Reload .bashrc:

source ~/.bashrc

Usage example (resize and optimize single image):

optimizeImage "/var/www/html/wp-content/uploads/2024/04/image.png" 1400 1400 85

Usage example (resize and optimize multiple images):

declare -a files=("/var/www/html/wp-content/uploads/2024/04/image.png" "/var/www/html/wp-content/uploads/2024/04/image.jpg")

for i in "${files[@]}"
do
    optimizeImage $i 1400 1400 85
done

sakirsensoy/image-resizer-and-optimizer.md