keras-team/keras · error · ValueError

Expected `padding` to be a tuple of 2 tuples of 2 integers.

Error message

Expected `padding` to be a tuple of 2 tuples of 2 integers. Received: padding={padding}

What it means

Error "Expected `padding` to be a tuple of 2 tuples of 2 integers. Received: padding={padding}" thrown in keras-team/keras.

Source

Thrown at keras/src/legacy/backend.py:2016

        valid_mask = tf.reshape(valid_mask, res_shape)
        res = tf.scatter_nd(tf.where(valid_mask), res, res_shape)
        res._keras_mask = valid_mask

        return res

    if update_shape and output_rank >= 3:
        # If our output includes timesteps or
        # spatial dimensions we need to reshape
        res = tf.reshape(res, output_shape[:-1])

    return res


@keras_export("keras._legacy.backend.spatial_2d_padding")
def spatial_2d_padding(x, padding=((1, 1), (1, 1)), data_format=None):
    """DEPRECATED."""
    if len(padding) != 2 or len(padding[0]) != 2 or len(padding[1]) != 2:
        raise ValueError(
            "Expected `padding` to be a tuple of 2 tuples of 2 integers. "
            f"Received: padding={padding}"
        )
    if data_format is None:
        data_format = backend.image_data_format()
    if data_format not in {"channels_first", "channels_last"}:
        raise ValueError(f"Unknown data_format: {data_format}")

    if data_format == "channels_first":
        pattern = [[0, 0], [0, 0], list(padding[0]), list(padding[1])]
    else:
        pattern = [[0, 0], list(padding[0]), list(padding[1]), [0, 0]]
    return tf.compat.v1.pad(x, pattern)


@keras_export("keras._legacy.backend.spatial_3d_padding")
def spatial_3d_padding(x, padding=((1, 1), (1, 1), (1, 1)), data_format=None):
    """DEPRECATED."""

View on GitHub (pinned to 7a34a03db6)

When it happens

Trigger: Thrown at keras/src/legacy/backend.py:2016 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/1c04179c96a569ab. Report an issue: GitHub.