ssd_batch_generator.py 文件源码

def _scale(image, min=0.9, max=1.1):
    '''
    Scale the input image by a random factor picked from a uniform distribution
    over [min, max].

    Returns:
        The scaled image, the associated warp matrix, and the scaling value.
    '''

    rows,cols,ch = image.shape

    #Randomly select a scaling factor from the range passed.
    scale = np.random.uniform(min, max)

    M = cv2.getRotationMatrix2D((cols/2,rows/2), 0, scale)
    return cv2.warpAffine(image, M, (cols, rows)), M, scale