Exception: Mask format 'png' does not allow 'binary' encoding! Allowed are: integer,rgb,rgba

[robmarkcole]

I want to annotate change detection and generate 8 bitmask.png which is single channel and 0 is no-change and 255 is change, which I think is pretty standard format. However the config below:

    "segmentation": {
        "path": "{id}/mask.png",
        "mask_encoding": "binary",
        "score": "f1",
        "mask_area": [0, 0, 256, 256],
        "unverified_threshold": 1,
        "test_images": null
    },

Returns

Exception: Mask format 'png' does not allow 'binary' encoding! Allowed are: integer,rgb,rgba