initial/preprocess.json

{
    "stages": [
        {
            "background_color": [
                0,
                0,
                0
            ],
            "interpolation": "lanczos",
            "size": [
                512,
                512
            ],
            "type": "pad_to_size"
        },
        {
            "type": "to_tensor"
        }
    ]
}