Basic command line switch reference


Only the most usual switches are described here. However those should be sufficient for the vast majority of users.

switch parameter
--abr average bitrate encoding
-b bitrate (8...320)
--decode decoding only
-f fast mode
-h high quality
--help help
-m stereo mode (s, j, f, m)
-V VBR quality setting (0...9)

* --abr n    average bitrate encoding
Turns on encoding with a targeted average bitrate of n kbits, allowing to use frames of different sizes. The allowed range of n is 4-310, you can use any integer value within that range.



* -b n    bitrate
For MPEG1 (sampling frequencies of 32, 44.1 and 48kHz)
n = 32,40,48,56,64,80,96,112,128,160,192,224,256,320

For MPEG2 (sampling frequencies of 16, 22.05 and 24kHz)
n = 8,16,24,32,40,48,56,64,80,96,112,128,144,160

Default is 128 kbs for MPEG1 and 80 kbs for MPEG2.



* --decode    decoding only
Uses LAME for decoding to a wav file. The input file can be any input type supported by encoding, including layer I,II,III (MP3).




* -f    fast mode
This switch forces the encoder to use a faster encoding mode, but with a lower quality.




* -h    high quality
Use some quality improvements. Encoding will be slower, but the result will be of higher quality.
This switch is always enabled when using VBR.




* --help    help
Display a list of all available options.




* -m s/j/m    stereo mode
Joint-stereo is the default mode for stereo files with VBR when -v is more than 4 or fixed bitrates of 160kbs or less. At higher fixed bitrates or higher VBR settings, the default is stereo.

stereo

Normal stereo mode.

joint stereo
In this mode, the encoder will make use of a correlation between both channels in order to achieve higher compression. This will enhance the quality of constant bitrate recordings, and reduce the size of variable bitrate recordings.

mono
The input will be encoded as a mono signal.




* -V 0...9    VBR quality setting
Enable VBR (Variable BitRate) and specifies the value of VBR quality.
default=4
0=highest quality.