lv2file - Apply LV2 effects to audio files
lv2file
-l|--list
-n|--nameports PLUGIN
-i INFILE -o OUTFILE [ OPTIONS ] PLUGIN
lv2file is aprogram which you can use to apply effects to your
audio files without much hassle. Possible use cases are:
* To apply an effect without having to open a GUI or
start a project.
* To apply effects to a large number of files, or in an automated manner.
* A deterministic environment to debug a plugin.
* Audio editing in a command-line only environment
lv2file uses the LV2 plugin format (http://lv2plug.in/) for the effects it uses.
lv2file follows the usual GNU command line syntax, with long
options starting with two dashes (`-'). A summary of options is included
below.
- -l, --list
- List and number all available plugins.
- -n --nameports
PLUGIN
- List all the input and control ports for the specified plugin.
- -i FILE
- Input the audio from a given FILE. Most common sampled audio formats are
supported.
- -o FILE
- Output to given FILE. If "-" is given and "--channels"
and "--rate" are both specified, then output will be written as
raw, 32-bit floating point samples to stdout.
- -n, --channels
CHANNELS
- Specify the channel count when reading from stdin and writing to
stdout.
- -r, --rate
RATE
- Specify the sample rate reading from stdin and writing to stdout.
- -c, --connect
CHANNEL:PORT
- Connect the channel CHANNEL in the input file to the audio port PORT of
the plugin. If you connect multiple channels to the same port, they will
be mixed together. The -c option is often not necessary, as lv2file will
try to guess how you would like to connect the ports.
It is possible to run multiple instances of a plugin using the syntax
"-c 5:2.left" which, for example, would connect the fifth
channel of audio to the port labeled "left" in the second copy
of the plugin. You don't need to specify how many plugins to run, lv2file
automatically makes enough according to the connections you make.
- -p, --parameters
PORT:VALUE
- Pass values to the control ports of the plugin, essentially telling the
effect how to handle the audio. PORT is the name of the control port, and
VALUE is the value to set it to. For example "-p volume:1" sets
the effects "volume" control to 1.
You should note that because lv2file uses LV2 plugins, the
VALUES will always be floating point numbers. It is not possible to vary
a parameter with time. It is also not possible to have different control
values for multiple plugin instances. Instead, split up the channels of
your audio files, and process them in batches whose parameters are all
the same.
- [ -m --mono ]
- Mix down all of the channels together and pass them to the plugin. This
will only work if the plugin has only a single audio input. This is to be
used instead of manually specifying connections.
- [ -b, --blocksize N ]
- The size of the chunks the audio is processed in. This might have
implications for speed of processing. N is measured in frames, not
samples. The default is 512.
- [ --ignore-clipping ]
- By default, lv2file will check every sample for clipping and will warn the
user if any clipping occurs. However, if know that the effect won't
produce clipping, or you don't care if it does, you can use this option to
turn off the check for clipping. This will make lv2file run slightly
faster.
lv2file was written by Jeremy Salwen
<jeremysalwen@gmail.com>.
This manual page was written by Jeremy Salwen
<jeremysalwen@gmail.com>, for the Debian project (and may be used by
others).