1 AUDIORECORD(1) User Commands AUDIORECORD(1) 2 3 4 5 NAME 6 audiorecord - record an audio file 7 8 SYNOPSIS 9 audiorecord [-af] [-v vol] [-c channels] [-s rate] 10 [-e encoding] [-t time] [-i info] [-d dev] 11 [-T au|aif[f]|wav] [file[.au|.aif[f]|.wav]] 12 13 14 DESCRIPTION 15 The audiorecord utility copies audio data from the audio device to a 16 named audio file, or to the standard output if no filename is present. 17 If no output file is specified and standard output is a tty, the 18 program exits with an error message. 19 20 21 By default, monaural audio data is recorded at 8 kHz and encoded in u- 22 law format. If the audio device supports additional configurations, the 23 -c, -s, and -e options may be used to specify the data format. The 24 output file is prefixed by an audio file header that identifies the 25 format of the data encoded in the file. 26 27 28 Recording begins immediately and continues until a SIGINT signal (for 29 example, Control-c) is received. If the -t option is specified, 30 audiorecord stops when the specified quantity of data has been 31 recorded. 32 33 34 If the audio device is unavailable, that is, if another process 35 currently has read access, audiorecord prints an error message and 36 exits immediately. 37 38 OPTIONS 39 The following options are supported: 40 41 -? 42 Help: Prints a command line usage message. 43 44 45 -a 46 Append: Appends the data on the end of the 47 named audio file. The audio device must support 48 the audio data format of the existing file. 49 50 51 -c channels 52 Channels: Specifies the number of audio 53 channels (1 or 2). The value may be specified 54 as an integer or as the string mono or stereo. 55 The default value is mono. 56 57 58 -d dev 59 Device: The dev argument specifies an alternate 60 audio device from which input should be taken. 61 If the -d option is not specified, the AUDIODEV 62 environment variable is consulted (see below). 63 Otherwise, /dev/audio is used as the default 64 audio device. 65 66 67 -e encoding 68 Encoding: Specifies the audio data encoding. 69 This value may be one of ulaw, alaw, or linear. 70 The default encoding is ulaw. 71 72 73 -f 74 Force: When the -a flag is specified, the 75 sample rate of the audio device must match the 76 sample rate at which the original file was 77 recorded. If the -f flag is also specified, 78 sample rate differences are ignored, with a 79 warning message printed on the standard error. 80 81 82 -i info 83 Information: The `information' field of the 84 output file header is set to the string 85 specified by the info argument. This option 86 cannot be specified in conjunction with the -a 87 argument. 88 89 90 -s rate 91 Sample Rate: Specifies the sample rate, in 92 samples per second. If a number is followed by 93 the letter k, it is multiplied by 1000 (for 94 example, 44.1k = 44100). The default sample 95 rate is 8 kHz. 96 97 98 -t time 99 Time: The time argument specifies the maximum 100 length of time to record. Time can be specified 101 as a floating-point value, indicating the 102 number of seconds, or in the form: hh:mm:ss.dd, 103 where the hour and minute specifications are 104 optional. 105 106 107 -T au | aif[f] | wav 108 Specifies the audio file type to create. If the 109 -a option is used, the file type must match the 110 file to which it is being appended. Regardless 111 of the file suffix, the type is set as 112 specified in this option. If this option is not 113 specified, the file suffix determines the type. 114 115 116 -v vol 117 Volume: The recording gain is set to the 118 specified value before recording begins, and is 119 reset to its previous level when audiorecord 120 exits. The vol argument is an integer value 121 between 0 and 100, inclusive. If this argument 122 is not specified, the input volume remains at 123 the level most recently set by any process. 124 125 126 OPERANDS 127 file[.au|.aif[f]|.wav] 128 129 File Specification: The named audio file is rewritten, or appended. 130 If no filename is present, and standard output is not a tty, or if 131 the special filename "-" is specified, output is directed to the 132 standard output. 133 134 If the -T option is not specified, the file suffix determines the 135 type of file. If the suffix is not recognized, the default is .au. 136 If the -T option is specified, that file type is used regardless of 137 the file suffix. 138 139 140 USAGE 141 See largefile(5) for the description of the behavior of audiorecord 142 when encountering files greater than or equal to 2 Gbyte (2^31 bytes). 143 144 ENVIRONMENT VARIABLES 145 AUDIODEV 146 The full path name of the audio device to record from, if 147 no -d argument is supplied. If the AUDIODEV variable is not 148 set, /dev/audio is used. 149 150 151 SEE ALSO 152 audioconvert(1), audioplay(1), largefile(5), audio(7I) 153 154 155 156 February 8, 2020 AUDIORECORD(1)