[flac-dev] Why Rice order in "--best" switch is limited to 6?

Барт Гопник bart.gopnik at gmail.com
Tue Jan 7 07:46:15 PST 2014


I think "-r 8" is "highest reasonable". E.g. from 5 to 12 values of
"-compression_level" switch in FFMPEG uses value 8 of Rice order
parameter.


> IMHO it just means "highest reasonable", not "highest theoretically possible".


>> "--best" preset is designed for highest compression, not for faster
>> compression, isn't it?


>>> Because -r 8 is noticeable slower? The size difference is 0,0003%,
>>> the speed difference is 30...40%.
>>>
>>> BTW, you can also use -A=... options to increase compression ratio.


>>>> The "--best" switch currently synonymous with "-8" that synonymous
>>>> with "--compression-level-8" that synonymous with "-l 12 -b 4096 -m -e
>>>> -r 6".
>>>>
>>>> Why value of "-r" switch in "--best" is limited to 6?
>>>>
>>>> The maximum Rice order is 8 (not 6) for the stream to be Subset compatible.
>>>>
>>>> "-r 8" ("-l 12 -b 4096 -m -e -r 8") produces better results than "-r
>>>> 6" ("-l 12 -b 4096 -m -e -r 6") and and also Subset compatible.


More information about the flac-dev mailing list