Exemplo n.º 1
0
    def __init__(self, method):
        if not isinstance(method, str):
            raise ValueError(f'Invalid method type "{type(method)}"')

        from compressai import available_entropy_coders

        if method not in available_entropy_coders():
            methods = ", ".join(available_entropy_coders())
            raise ValueError(f'Unknown entropy coder "{method}"'
                             f" (available: {methods})")

        if method == "ans":
            from compressai import ans

            encoder = ans.RansEncoder()
            decoder = ans.RansDecoder()
        elif method == "rangecoder":
            import range_coder

            encoder = range_coder.RangeEncoder()
            decoder = range_coder.RangeDecoder()

        self.name = method
        self._encoder = encoder
        self._decoder = decoder
Exemplo n.º 2
0
    def __init__(self, method):
        if not isinstance(method, str):
            raise ValueError(f'Invalid method type "{type(method)}"')

        from compressai import available_entropy_coders
        if method not in available_entropy_coders():
            methods = ', '.join(available_entropy_coders())
            raise ValueError(f'Unknown entropy coder "{method}"'
                             f' (available: {methods})')

        if method == 'ans':
            from compressai import ans  # pylint: disable=E0611
            encoder = ans.RansEncoder()
            decoder = ans.RansDecoder()
        elif method == 'rangecoder':
            import range_coder  # pylint: disable=E0401
            encoder = range_coder.RangeEncoder()
            decoder = range_coder.RangeDecoder()

        self._encoder = encoder
        self._decoder = decoder
Exemplo n.º 3
0
def apply_range_decoder(seq_data_len, decodepath, args, config):
    resolution = config['resolution']
    prob = np.load('data_info/distribution_info_{}.npy'.format(args.model_num))

    # Avoid zero prob
    modified_freq = prob * resolution + 1
    modified_prob = modified_freq / np.sum(modified_freq)

    # print(modified_prob)

    cum_freq = range_coder.prob_to_cum_freq(modified_prob,
                                            resolution=resolution)

    # print('-----')
    # print(cum_freq)

    # cum_freq = [0] + [i for i in range(1, 256 + 1)]

    range_decoder = range_coder.RangeDecoder(decodepath)

    # Whether cum_freq resolution influences performance ?
    seq_data = range_decoder.decode(seq_data_len, cum_freq)

    return seq_data