pix2pix_preprocess.js

function preprocess(imgData) {
    return tf.tidy(() => {
        //convert to a tensor 
        const tensor = tf.fromPixels(imgData).toFloat()

        //resize 
        const resized = tf.image.resizeBilinear(tensor, [256, 256])
                
        //normalize 
        const offset = tf.scalar(127.5);
        const normalized = resized.div(offset).sub(tf.scalar(1.0));

        //We add a dimension to get a batch shape 
        const batched = normalized.expandDims(0)
        
        return batched
    })
}