arecord, aplay − command-line sound recorder and player for ALSA soundcard driver
SYNOPSIS
arecord [flags] [filename]
aplay [flags] [filename [filename]] ...
aplay is much the same, only it plays instead of recording. For supported soundfile formats, the sampling rate, bit depth, and so forth can be automatically determined from the soundfile header.
If filename is not specified, the standard output or input is used. The aplay utility accepts multiple filenames.
OPTIONS
−h, −−help
Help: show syntax.
−−version
Print current version.
−l, −−list−devices
List all soundcards and digital audio devices
−L, −−list−pcms
List all PCMs defined
−D, −−device=NAME
Select PCM by name
−q −−quiet
Quiet mode. Suppress messages (not sound :))
−t, −−file−type TYPE
File type (voc, wav, raw or au). If this parameter is omitted the WAVE format is used.
−c, −−channels=#
The number of channels. The default is one channel.
−f −−format=FORMAT
Sample format
Recognized sample formats are: S8 U8 S16_LE S16_BE U16_LE U16_BE S24_LE S24_BE U24_LE U24_BE S32_LE S32_BE U32_LE U32_BE FLOAT_LE FLOAT_BE FLOAT64_LE FLOAT64_BE IEC958_SUBFRAME_LE IEC958_SUBFRAME_BE MU_LAW A_LAW IMA_ADPCM MPEG GSM
Some of these may not be available on selected hardware
There are also two format shortcuts available:
−f cd (16 bit little endian, 44100, stereo [−f S16_LE −c2 −r44100]
−f dat (16 bit little endian, 48000, stereo) [−f S16_LE −c2 −r48000]
If no format is given U8 is used.
−r, −−rate=#
Sampling rate in Hertz. The default rate is 8000 Hertz.
−d, −−duration=#
Interrupt after # seconds. A value of zero means infinity. The default is zero, so if this option is omitted then the arecord process will run until it is killed.
−s, −−sleep−min=#
Min ticks to sleep. The default is not to sleep.
−M, −−mmap
Use memory-mapped (mmap) I/O mode for the audio stream. If this option is not set, the read/write I/O mode will be used.
−N, −−nonblock
Open the audio device in non-blocking mode. If the device is busy the program will exit immediately. If this option is not set the program will block until the audio device is available again.
−F, −−period−time=#
Distance between interrupts is # microseconds. If no period time and no period size is given then a quarter of the buffer time is set.
−B, −−buffer−time=#
Buffer duration is # microseconds If no buffer time and no buffer size is given then the maximal allowed buffer time but not more than 500ms is set.
−−period−size=#
Distance between interrupts is # frames If no period size and no period time is given then a quarter of the buffer size is set.
−−buffer−size=#
Buffer duration is # frames If no buffer time and no buffer size is given then the maximal allowed buffer time but not more than 500ms is set.
−A, −−avail−min=#
Min available space for wakeup is # microseconds
−R, −−start−delay=#
Delay for automatic PCM start is # microseconds (relative to buffer size if <= 0)
−T, −−stop−delay=#
Delay for automatic PCM stop is # microseconds from xrun
−v, −−verbose
Show PCM structure and setup. This option is accumulative. The VU meter is displayed when this is given twice or three times.
−V, −−vumeter=TYPE
Specifies the VU-meter type, either stereo or mono. The stereo VU-meter is available only for 2-channel stereo samples with interleaved format.
−I, −−separate−channels
One file for each channel
Example:
aplay −c 1 −t raw −r 22050 −f mu_law foobar
will play the raw file "foobar" as a 22050-Hz, mono, 8-bit, Mu-Law .au file.
arecord −d 10 −f cd −t wav −D copy foobar.wav
will record foobar.wav as a 10-second, CD-quality wave file, using the PCM "copy" (which might be defined in the user’s .asoundrc file as:
pcm.copy {
type plug
slave {
pcm hw
}
route_policy copy
}
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