Command line switch reference

switch parameter
-a downmix stereo file to mono
-b bitrate (32, 40, 48, 56, 64, 96, 112, 128, 160, 192, 224, 256, 320)
-c copyright
-e de-emphasis (n, 5, c)
-f fast mode
-g turn on MP3x graphical frame analyser (might not be available on your release)
-h high quality
-k full bandwidth
-m stereo mode (s, j, f, m)
--nohist disable histogram display
-o non-original
-p error protection
-r input file is raw pcm
-s sampling frequency
-S silent operation
-t disable VBR tag
-V VBR quality setting (0...9)
-x swapbytes

-a    downmix 
Mix the stereo input file to mono and encode as mono. This option is only needed in the case of raw PCM stereo input (because LAME cannot determine the number of channels in the input file).
To encode a stereo PCM input file as mono, use "lame -m s -a".
For WAV and AIFF input files, using "-m m" will always produce a mono .mp3 file from both mono and stereo input.
The downmix is calculated as the sum of the left and right channel, attenuated by 6 dB.


-b    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 128kbs MPEG1, 80kbs MPEG2. When used with variable bitrate encodings (VBR), -b specifies the minimum bitrate to use. This is useful to prevent LAME VBR from using some very aggressive compression which can cause some distortion due to small flaws in the psycho-acoustic model.


-c    copyright
Mark the encoded file as being copyrighted.


-e n/5/c    de-emphasis

default=n (none)


-f    fast mode
This switch forces the encoder to use the fast encoding mode. It will reduce a lot the quality of the output. This might be useful for real-time processing or streaming on slowest computers.


-h    high quality
Enables specialized mid/side masking thresholds to be used in jstereo mode. Will sound better but is 20% slower. It is only effective on joint stereo encoding.


-k    full bandwidth
Tells the encoder to use full bandwidth. By default, the encoder uses a 16kHz bandwidth up to 64kbps per channel, and full bandwidth at higher bitrates. Increasing the bandwidth from the default setting might produces ringing artefacts at low bitrates. Use with care!


-m s/j/f/m    stereo mode
jstereo is the default mode for stereo files with VBR or fixed bitrates of 160kbs or less. At higher fixed bitrates, the default is stereo.

stereo

In this mode, the encoder makes no use of potentially existing correlations between the two input channels. It can, however, negotiate the bit demand between both channel, i.e. give one channel more bits if the other contains silence.

joint stereo
In this mode, the encoder will make use of a correlation between both channels. The signal will be matrixed into a sum ("mid") and difference ("side") signal. For quasi-mono signals, this will give a significant gain in encoding quality.
This mode does not destroy phase information like IS stereo that may be used by other encoders and thus can be used to encode DOLBY ProLogic surround signals.

forced joint stereo
This mode will force MS joint stereo on all frames. It's slightly faster then jstereo. But it should only be used if you are sure every frame of the input file has very little stereo seperation.

mono
The input will be encoded as a mono signal. If it was a stereo signal, it will be downsampled to mono.


--nohist    disable histogram display
By default, LAME will display a bitrate histogram while producing VBR mp3 files. This will disable that feature.
Histogram display might not be available on your release.


-o    non-original
Mark the encoded file as a copy.


-p    error protection
Turn on CRC error protection.


-r    input file is raw pcm
Assume the input file is raw pcm. Sampling rate and mono/stereo/jstereo must be specified on the command line. Without -r, LAME will perform several fseek()'s on the input file looking for WAV and AIFF headers.
Might not be available on your release.


-s 16/22.05/24/32/44.1/48    sampling frequency
Required only for raw PCM input files. Otherwise it will be determined from the header.


-S    silent operation
Don't print progress report.


-t    disable VBR tag
Disable writing of the VBR Tag (only valid in VBR mode).
This tag in embedded in frame 0 of the MP3 file. It lets VBR aware players correctly seek and compute playing times of VBR files.


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


-x    swapbytes
Swap bytes in the input file. For sorting out little endian/big endian type problems. If your encodings sounds like static, try this first.