imageutil.py 文件源码

def load_image(filepath, as_grey=False, dtype='uint8', no_alpha=True):
    """
    Load image as numpy array from given filepath.

    Supported formats: gif, png, jpg, bmp, tif, npy

    >>> img = load_image('tests/data/img_formats/nut_color.jpg')
    >>> shapestr(img)
    '213x320x3'

    :param string filepath: Filepath to image file or numpy array.
    :param bool as_grey:
    :return: numpy array with shapes
             (h, w) for grayscale or monochrome,
             (h, w, 3) for RGB (3 color channels in last axis)
             (h, w, 4) for RGBA (for no_alpha = False)
             (h, w, 3) for RGBA (for no_alpha = True)
             pixel values are in range [0,255] for dtype = uint8
    :rtype: numpy ndarray
    """
    if filepath.endswith('.npy'):  # image as numpy array
        arr = np.load(filepath).astype(dtype)
        arr = rgb2gray(arr) if as_grey else arr
    else:
        # img_num=0 due to 
        # https://github.com/scikit-image/scikit-image/issues/2406
        arr = ski.imread(filepath, as_grey=as_grey, img_num=0).astype(dtype)
    if arr.ndim == 3 and arr.shape[2] == 4 and no_alpha:
        arr = arr[..., :3]  # cut off alpha channel
    return arr