What kind of distortion are they applying?!Looking at the waveform, it seems a large part of the track is almost a square wave. So, it isn't far from chiptune. 1131 for FLAC -r 9 --laxInteresting. The r value goes up exponentially. So -r12 means: split the block up into 2^12 partitions, which is 4096 partitions. That is equal to the blocksize, and doesn't really make sense. Furthermore, FLAC limits r internally, as specified by the format. The number of samples in the first partition has the predictor order subtracted, and the number of samples in a partition cannot be zero. Therefore, -r12 can only lead to 4096 partitions when a fixed predictor with order 0 is used, which isn't very useful here. When a predictor order of 1 is used, -r12 is internally limited to -r11, and when a predictor order of 2 is used this is further limited to -r10, with a predictor order of 4 to -r9 and so forth. 1090-ish for SAC at default. A codec that isn't usable for playback. 1073 for FLAC -r 10 --lax (only the Stellar Descent tracks benefit, the first track is to the byte same size) 1058 for FLAC -r 11 --lax (ditto) - and same byte count for -r 12. 1071 for -r 12,12 enforcing the "12" as minimum. 1058 for FLAC -8 -r 11 --lax - and same byte count going to -r 12 1052 for FLAC -8pe -r12 --lax, didn't try 11. New FLAC build improves 12 kilobytes. It seems reasonable to assume -r12 won't differ from -r11. However, the fact that -r11 is smaller than -r10 is really stunning indeed. It means that for each 2 samples, one rice parameter is stored, which is a 4-bit overhead AND it means the predictor order is no larger than 1. It is very rare this pays of, but it does here. So, why does FLAC outperform very advanced codecs like SAC here? Because these high partition orders make FLAC able to 'switch' extremely quickly if the signal does so too. If you look at the signal, it is almost a square wave: you have some samples (about 10) with exactly the same value, then a upwards slope for a few samples, than some more samples with exactly the same value, then a downward slope. With an extremely high partition order, FLAC can spend few bits on the samples with the exact same value and spend more bits on the slopes. If you use -r6 like the presets do, all these samples need to use the same number of bits (more exact: the same rice parameter) to be described. It seems this is something only FLAC does, apparently, if it beats all other codecs. It is however specific to certain kinds of music, it seems.
Last Edit: 2022-08-27 20:30:55 by ktf