images.py 文件源码

def yuv2rgb(yuv):
    """
    Convert YUV image into RGB https://en.wikipedia.org/wiki/YUV
    """
    yuv = tf.multiply(yuv, 255)
    yuv2rgb_filter = tf.constant([[[[1., 1., 1.], [0., -0.34413999, 1.77199996],
                                    [1.40199995, -0.71414, 0.]]]])
    yuv2rgb_bias = tf.constant([-179.45599365, 135.45983887, -226.81599426])

    yuv = tf.expand_dims(yuv, 0)
    temp = tf.nn.conv2d(yuv, yuv2rgb_filter, [1, 1, 1, 1], 'SAME')
    temp = tf.nn.bias_add(temp, yuv2rgb_bias)
    temp = tf.maximum(temp, tf.zeros(temp.get_shape(), dtype=tf.float32))
    temp = tf.minimum(temp,
                      tf.multiply(
                          tf.ones(temp.get_shape(), dtype=tf.float32), 255))
    temp = tf.divide(temp, 255)
    temp = tf.squeeze(temp, [0])
    return temp