70 lines
1.6 KiB
Python
70 lines
1.6 KiB
Python
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###############################################################################
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# RLE encoder
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###############################################################################
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# Takes any binary file and converts to RLE sequenced (ended with length 0)
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# Input: FF FF FF FF FF FF FF FF FF 0A FF FF FF
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# Output: 09 FF 01 0A 03 FF 00
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###############################################################################
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import os
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import sys
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import math
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input = sys.argv[1]
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if len(sys.argv) == 1:
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print("Usage:\n $ python3 ./rle.py <BIN_FILENAME>\n\nOutput .rle format.")
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sys.exit()
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def compress(data):
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output = []
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i = 1
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total = 0
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char = data[0]
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count = 1
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while i <= len(data):
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if i == len(data):
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output.append(bytes([count]))
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output.append(bytes([char]))
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total += count
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break
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if char == data[i]:
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count += 1
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if count == 255:
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total += count
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output.append(bytes([count]))
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output.append(bytes([char]))
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count = 0
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i += 1
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continue
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else:
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total += count
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output.append(bytes([count]))
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output.append(bytes([char]))
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count = 1
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char = data[i]
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i += 1
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continue
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print(total, "bytes compresed to", len(output))
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return output
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def read_file_bytes(file):
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with open(file, 'rb') as f:
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return f.read()
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def read_file(input):
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inbytes = read_file_bytes(input)
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output = compress(inbytes)
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f = None
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try:
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f = open(input.split('.')[0]+".rle", "wb")
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for b in output:
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f.write(b)
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f.write(b'\x00')
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finally:
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f.close()
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read_file(input)
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print("File written successfully.")
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