Source code for rastervision.core.rv_pipeline.utils

import numpy as np


def nodata_below_threshold(chip: np.ndarray,
                           threshold: float,
                           nodata_val: int = 0) -> bool:
    """Check if proportion of nodata pixels is below the threshold.

    Args:
        chip (np.ndarray): Raster as (H, W) or (H, W, C) numpy array.
        threshold (float): Threshold to check the fraction of NODATA pixels
            against.
        nodata_val (int, optional): Value that represents NODATA pixels.
            Defaults to 0.

    Returns:
        bool: Whether the fraction of NODATA pixels is below the given
        threshold.
    """
    if chip.ndim == 3:
        # (H, W, C) --> (H, W)
        chip = chip.sum(axis=-1)
    nodata_prop = (chip == nodata_val).mean()
    return nodata_prop < threshold