def compress(filename):
text = util.load_file_as_text(filename)
encoded_values = encode(text)
encoded_bytes = bytes(encoded_values)
output = util.get_output_filename(filename)
util.save_file_as_bytes(output, encoded_bytes)
print(util.get_compression_ratio(encoded_bytes, text))
def compress(filename):
text = util.load_file_as_text(filename)
encoded_text = encode(text)
encoded_bytes = util.to_byte_array(encoded_text)
output = util.get_output_filename(filename)
save(encoded_bytes, output)
print(util.get_compression_ratio(encoded_bytes, text))
def compress(filename):
text = util.load_file_as_text(filename)
probs = util.calc_prob(text)
ranges = calc_range(probs)
encoded_value = encode(text, ranges)
encoded_bytes = bytearray(struct.pack("f", encoded_value))
output = util.get_output_filename(filename)
save(encoded_bytes, ranges, len(text), output)
print(util.get_compression_ratio(encoded_bytes, text))
def compress(filename, n=8):
text = util.load_file_as_text(filename)
probs = calc_prob(text)
codes = build_code(probs, n)
encoded_text = encode(text, codes)
encoded_bytes = util.to_byte_array(encoded_text)
output = util.get_output_filename(filename)
save(encoded_bytes, codes, output)
print(util.get_compression_ratio(encoded_bytes, text))
def compress(filename):
text = util.load_file_as_text(filename)
freq = calc_freq(text)
heap = make_heap(freq)
root = build_tree(heap)
codes = build_codes(root)
encoded_text = encode(codes, text)
encoded_bytes = util.to_byte_array(encoded_text)
output = util.get_output_filename(filename)
save(encoded_bytes, codes, output)
print(util.get_compression_ratio(encoded_bytes, text))
def coding_test(compress_function, decompress_function):
filename = 'test/files/bookkeeper'
backup_filename = filename + '.backup'
output_filename = util.get_output_filename(filename)
shutil.copyfile(filename, backup_filename)
try:
compress_function(filename)
decompress_function(output_filename)
with open(filename) as source:
with open(backup_filename) as backup:
equal = source.read() == backup.read()
os.remove(output_filename)
except RuntimeError:
equal = False
os.remove(filename)
os.rename(backup_filename, filename)
return equal
def test_get_output_filename_with_extension(self):
self.assertEqual(self.bookkeeper + '.ext', util.get_output_filename(self.bookkeeper, 'ext'))
def test_get_output_filename(self):
self.assertEqual(self.bookkeeper + '.output', util.get_output_filename(self.bookkeeper))