keras-team/keras · error · ValueError

If imagenet weights are being loaded, alpha can be one of `0

Error message

If imagenet weights are being loaded, alpha can be one of `0.75`, `1.0` for non minimalistic or `1.0` for minimalistic only.

What it means

Error "If imagenet weights are being loaded, alpha can be one of `0.75`, `1.0` for non minimalistic or `1.0` for minimalistic only." thrown in keras-team/keras.

Source

Thrown at keras/src/applications/mobilenet_v3.py:277

    if backend.image_data_format() == "channels_last":
        row_axis, col_axis = (0, 1)
    else:
        row_axis, col_axis = (1, 2)
    rows = input_shape[row_axis]
    cols = input_shape[col_axis]
    if rows and cols and (rows < 32 or cols < 32):
        raise ValueError(
            "Input size must be at least 32x32; Received `input_shape="
            f"{input_shape}`"
        )
    if weights == "imagenet":
        if (
            not minimalistic
            and alpha not in [0.75, 1.0]
            or minimalistic
            and alpha != 1.0
        ):
            raise ValueError(
                "If imagenet weights are being loaded, "
                "alpha can be one of `0.75`, `1.0` for non minimalistic "
                "or `1.0` for minimalistic only."
            )

        if rows != cols or rows != 224:
            warnings.warn(
                "`input_shape` is undefined or non-square, "
                "or `rows` is not 224. "
                "Weights for input shape (224, 224) will be "
                "loaded as the default.",
                stacklevel=2,
            )

    if input_tensor is None:
        img_input = layers.Input(shape=input_shape)
    else:
        if not backend.is_keras_tensor(input_tensor):

View on GitHub (pinned to 7a34a03db6)

When it happens

Trigger: Thrown at keras/src/applications/mobilenet_v3.py:277 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of keras-team/keras@7a34a03db6 (2026-08-25). Data as JSON: /api/errors/2f01c1062e796df6. Report an issue: GitHub.