embed.py 文件源码

def five_crops(image, crop_size):
    """ Returns the central and four corner crops of `crop_size` from `image`. """
    image_size = tf.shape(image)[:2]
    crop_margin = tf.subtract(image_size, crop_size)
    assert_size = tf.assert_non_negative(
        crop_margin, message='Crop size must be smaller or equal to the image size.')
    with tf.control_dependencies([assert_size]):
        top_left = tf.floor_div(crop_margin, 2)
        bottom_right = tf.add(top_left, crop_size)
    center       = image[top_left[0]:bottom_right[0], top_left[1]:bottom_right[1]]
    top_left     = image[:-crop_margin[0], :-crop_margin[1]]
    top_right    = image[:-crop_margin[0], crop_margin[1]:]
    bottom_left  = image[crop_margin[0]:, :-crop_margin[1]]
    bottom_right = image[crop_margin[0]:, crop_margin[1]:]
    return center, top_left, top_right, bottom_left, bottom_right