readers.py 文件源码

def get_video_matrix(self,
                       features,
                       feature_size,
                       max_frames,
                       max_quantized_value,
                       min_quantized_value):
    """Decodes features from an input string and quantizes it.

    Args:
      features: raw feature values
      feature_size: length of each frame feature vector
      max_frames: number of frames (rows) in the output feature_matrix
      max_quantized_value: the maximum of the quantized value.
      min_quantized_value: the minimum of the quantized value.

    Returns:
      feature_matrix: matrix of all frame-features
      num_frames: number of frames in the sequence
    """
    decoded_features = tf.reshape(
        tf.cast(tf.decode_raw(features, tf.uint8), tf.float32),
        [-1, feature_size])

    num_frames = tf.minimum(tf.shape(decoded_features)[0], max_frames)
    feature_matrix = utils.Dequantize(decoded_features,
                                      max_quantized_value,
                                      min_quantized_value)
    feature_matrix = resize_axis(feature_matrix, 0, max_frames)
    return feature_matrix, num_frames