def _seek(self, index, offsets=None):
data_stream = self._data_stream
data_base = self._data_base
if offsets is None:
offset = self.offsetof(index)
else:
offset = offsets[sequence_index(index, len(offsets))]
data_stream.seek(data_base + offset)
def _seek(self, index, offsets=None):
data_stream = self._data_stream
data_base = self._data_base
if offsets is None:
offset = self.offsetof(index)
else:
offset = offsets[sequence_index(index, len(offsets))]
data_stream.seek(data_base + offset)
def extract_chunk(self, index):
chunk_count = self._chunk_count
data_stream = self._data_stream
huffman_nodes = self._huffman_nodes
index = sequence_index(index, chunk_count)
chunk = b''
chunk_size = self.sizeof(index)
if chunk_size:
self._seek(index)
compressed_size, expanded_size = self._read_sizes(index)
chunk = stream_read(data_stream, compressed_size)
chunk = huffman_expand(chunk, expanded_size, huffman_nodes)
return chunk
def extract_chunk(self, index):
self._log_extract_chunk(index)
chunk_count = self._chunk_count
data_stream = self._data_stream
huffman_nodes = self._huffman_nodes
index = sequence_index(index, chunk_count)
chunk = b''
chunk_size = self.sizeof(index)
if chunk_size:
self._seek(index)
compressed_size, expanded_size = self._read_sizes(index)
chunk = stream_read(data_stream, compressed_size)
chunk = huffman_expand(chunk, expanded_size, huffman_nodes)
return chunk
def sizeof(self, index):
chunk_offsets = self._chunk_offsets
index = sequence_index(index, len(self))
return chunk_offsets[index + 1] - chunk_offsets[index]
def offsetof(self, index):
return self._chunk_offsets[sequence_index(index, len(self))]
def sizeof(self, index):
chunk_offsets = self._chunk_offsets
index = sequence_index(index, self._chunk_count)
return chunk_offsets[index + 1] - chunk_offsets[index]
def offsetof(self, index):
return self._chunk_offsets[sequence_index(index, self._chunk_count)]
