以 PDF 格式下载本书 (4620 KB)

audioplay(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | USAGE | ENVIRONMENT VARIABLES | ATTRIBUTES | SEE ALSO | BUGS

NAME

audioplay- play audio files

SYNOPSIS

audioplay [-iV] [-v vol] [-b bal] [-p speaker| headphone| line] [-d dev] [file...]

DESCRIPTION

The audioplay utility copies the named audio files (or the standard input if no filenames are present) to the audio device. If no input file is specified and standard input is a tty, the port, volume, and balance settings specified on the command line will be applied and the program will exit.

The input files must contain a valid audio file header. The encoding information in this header is matched against the capabilities of the audio device and, if the data formats are incompatible, an error message is printed and the file is skipped. Compressed ADPCM (G.721) monaural audio data is automatically uncompressed before playing.

Minor deviations in sampling frequency (that is, less than 1%) are ordinarily ignored. This allows, for instance, data sampled at 8012 Hz to be played on an audio device that only supports 8000 Hz. If the -V option is present, such deviations are flagged with warning messages.

OPTIONS

The following options are supported:

-i

Immediate: If the audio device is unavailable (that is, another process currently has write access), audioplay ordinarily waits until it can obtain access to the device. When the -i option is present, audioplay prints an error message and exits immediately if the device is busy.

-V

Verbose: Prints messages on the standard error when waiting for access to the audio device or when sample rate deviations are detected.

-v vol

Volume: The output volume is set to the specified value before playing begins, and is reset to its previous level when audioplay exits. The vol argument is an integer value between 0 and 100, inclusive. If this argument is not specified, the output volume remains at the level most recently set by any process.

-b bal

Balance: The output balance is set to the specified value before playing begins, and is reset to its previous level when audioplay exits. The bal argument is an integer value between -100 and 100, inclusive. A value of -100 indicates left balance, 0 middle, and 100 right. If this argument is not specified, the output balance remains at the level most recently set by any process.

-p speaker | headphone | line

Output Port: Selects the built-in speaker (the default), headphone jack, or line out as the destination of the audio output signal. If this argument is not specified, the output port will remain unchanged. Please note: Not all audio adapters support all of the output ports. If the named port does not exist, an appropriate substitute will be used.

-d dev

Device: The dev argument specifies an alternate audio device to which output should be directed. If the -d option is not specified, the AUDIODEV environment variable is consulted (see below). Otherwise, /dev/audio is used as the default audio device.

-\?

Help: Prints a command line usage message.

OPERANDS

file

File Specification: Audio files named on the command line are played sequentially. If no filenames are present, the standard input stream (if it is not a tty) is played (it, too, must contain an audio file header). The special filename `-' may be used to read the standard input stream instead of a file. If a relative path name is supplied, the AUDIOPATH environment variable is consulted (see below).

USAGE

See largefile(5) for the description of the behavior of audioplay when encountering files greater than or equal to 2 Gbyte ( 2³¹ bytes).

ENVIRONMENT VARIABLES

AUDIODEV

The full path name of the audio device to write to, if no -d argument is supplied. If the AUDIODEV variable is not set, /dev/audio is used.

AUDIOPATH

A colon-separated list of directories in which to search for audio files whose names are given by relative pathnames. The current directory (".") may be specified explicitly in the search path. If the AUDIOPATH variable is not set, only the current directory will be searched.

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
Architecture	SPARC, IA
Availability	SUNWauda
Interface Stability	Evolving

SEE ALSO

audioconvert(1), audiorecord(1), mixerctl(1), attributes(5), largefile(5), usb_ac(7D), audio(7I), mixer(7I)

BUGS

audioplay currently supports a limited set of audio format conversions. If the audio file is not in a format supported by the audio device, it must first be converted. For example, to convert to voice format on the fly, use the command:

---

example% audioconvert -f voice myfile | audioplay

---

The format conversion will not always be able to keep up with the audio output. If this is the case, you should convert to a temporary file before playing the data.

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | USAGE | ENVIRONMENT VARIABLES | ATTRIBUTES | SEE ALSO | BUGS