Assembly: Bass.Net (in Bass.Net.dll) Version: 220.127.116.11
Field ValueType: Int32
Like previous versions of WavPack (and many other compressors), WavPack 4.31 normally works "symmetrically" in that encoding and decoding operate at about the same rate (regardless of the mode used). However, WavPack now has an option to work "asymmetrically", so that extra processing can be done during encoding to provide better compression, but with NO corresponding cost to decoding performance!
This is enabled with the -x option and provides an average improvement in CD music compression of about 1% in "fast" mode, about 0.5% in the normal mode, and about 0.25% in "high" mode. Because the standard compression parameters are optimized for "normal" CD music audio, this option works best with "non-standard" audio (synthesized sounds, non-standard sampling rates, etc) where it can often achieve enormous gains. It should be noted that this mode is not just a little slower than the regular mode - it is MUCH slower. However, the fact that it has no effect on decode time could make it attractive in some situations.
The "extra" option provides a level of extra processing that has been optimized for the encoding mode selected (i.e. normal, "fast" or "high"). This level can be overridden with the optional numeric parameter from 1 to 6, although this is not generally recommended.