image_color_augment.py 文件源码

def random_saturation(img, label, lower=0.5, upper=1.5):
    """
    Multiplies saturation with a constant and clips the value between [0,1.0]
    Args:
        img: input image in float32
        label: returns label unchanged
        lower: lower val for sampling
        upper: upper val for sampling
    """
    alpha = lower + (upper - lower) * rand.rand()
    hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)

    # saturation should always be within [0,1.0]
    hsv[:, :, 1] = np.clip(alpha * hsv[:, :, 1], 0.0, 1.0)

    return cv2.cvtColor(hsv, cv2.COLOR_HSV2BGR), label