arecord, aplay − command-line sound recorder and player for ALSA soundcard driver |
arecord [flags] [filename] |
arecord is a command-line soundfile recorder for the ALSA soundcard driver. It supports several file formats and multiple soundcards with multiple devices. If recording with interleaved mode samples the file is automatically split before the 2GB filesize. 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. |
−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. Valid values are 1 through 32. |
−f −−format=FORMAT |
Sample format −f cd (16 bit little endian, 44100, stereo) [−f S16_LE −c2 −r44100] −f cdr (16 bit big endian, 44100, stereo) [−f S16_BE −c2 −f44100] −f dat (16 bit little endian, 48000, stereo) [−f S16_LE −c2 −r48000] If no format is given U8 is used. |
−r, −−rate=#<Hz> |
Sampling rate in Hertz. The default rate is 8000 Hertz. If the value specified is less than 300, it is taken as the rate in kilohertz. Valid values are 2000 through 192000 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. This option disables max−file−time and use−strftime, and ignores SIGUSR1. The stereo VU meter is not available with separate channels. |
−P |
Playback. This is the default if the program is invoked by typing aplay. |
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−C |
Record. This is the default if the program is invoked by typing arecord. |
−i, −−interactive |
Allow interactive operation via stdin. Currently only pause/resume via space or enter key is implemented. |
−−disable−resample |
Disable automatic rate resample. |
−−disable−channels |
Disable automatic channel conversions. |
−−disable−format |
Disable automatic format conversions. |
−−disable−softvol |
Disable software volume control (softvol). |
−−test−position |
Test ring buffer position. |
−−test−coef=<coef> |
Test coefficient for ring buffer position; default is 8. Expression for validation is: coef * (buffer_size / 2). Minimum value is 1. |
−−test−nowait |
Do not wait for the ring buffer--eats the whole CPU. |
−−max−file−time |
While recording, when the output file has been accumulating sound for this long, close it and open a new output file. Default is the maximum size supported by the file format: 2 GiB for WAV files. This option has no effect if −−separate−channels is specified. |
−−process−id−file <file name> |
aplay writes its process ID here, so other programs can send signals to it. |
−−use−strftime |
When recording, interpret %-codes in the file name parameter using the strftime facility whenever the output file is opened. The important strftime codes are: %Y is the year, %m month, %d day of the month, %H hour, %M minute and %S second. In addition, %v is the file number, starting at 1. When this option is specified, intermediate directories for the output file are created automatically. This option has no effect if −−separate−channels is specified. |
When recording, SIGINT, SIGTERM and SIGABRT will close the output file and exit. SIGUSR1 will close the output file, open a new one, and continue recording. However, SIGUSR1 does not work with −−separate−channels. |
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 } |
arecord −t wav −max-file_time 30 mon.wav |
Record from the default audio source in monaural, 8,000 samples per second, 8 bits per sample. Start a new file every 30 seconds. File names are mon-nn.wav, where nn increases from 01. The file after mon-99.wav is mon-100.wav. |
arecord −f cd −t wav −max-file-time 3600 --use-strftime %Y/%m/%d/listen-%H-%M-%v.wav |
Record in stereo from the default audio source. Create a new file every hour. The files are placed in directories based on their start dates and have names which include their start times and file numbers. |
alsamixer(1), amixer(1) |
Note that .aiff files are not currently supported. |
arecord and aplay are by Jaroslav Kysela <perex@perex.cz> This document is by Paul Winkler <zarmzarm@erols.com>. Updated for Alsa 0.9 by James Tappin <james@xena.uklinux.net> |