On Mon, 11 Jul 2016 10:52:08 -0700, jonas.thornvall wrote: > What kind of statistic law or mathematical conjecture or is it even a > physical law is violated by compression of random binary data?
You can't create an invertable mapping between a set with 2^N elements (e.g. the set of all N-bit binary sequences) and any set with fewer than 2^N elements (e.g. the set of all M-bit binary sequences for M<N). Lossless compression requires an invertable mapping. For any lossless compression algorithm, there will always be inputs where the output is larger than the input, even if only by a single bit. Practical lossless compression schemes operate by mapping likely inputs to short outputs and unlikely inputs to longer outputs, resulting in outputs which are /on average/ shorter than the inputs. Lossy compression can achieve as much compression as you want, providing that you're willing to tolerate the resulting loss of information. -- https://mail.python.org/mailman/listinfo/python-list
