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Record to audio file on disk


Save an audio file containing "real world" sound and/or sound created in MSP


Name Type Opt Description
number-of-input-channels int opt Sets the number of input channels, which determines the number of inlets that the sfrecord~ object will have. The maximum number of channels is 28, and the default is 1. The audio file created will have the same number of channels as this argument. Whether you can actually record the maximum number of channels is dependent on the speed of your processor and hard disk.


int recording-start/stop-flag (0 or nonzero) [int]
In left inlet: If a file has been opened with the open message, a non-zero value begins recording, and 0 stops recording and closes the file. sfrecord~ requires another open message to record again if a 0 has been sent.

Recording may also stop spontaneously if there is an error, such as running out of space on your hard disk.
format bit-depth [int]
A backwards-compatible message for file format. Use the samptype message for full soundfile specification.
loop looping-flag (0 or 1) [float]
In left inlet: The word loop, followed by 1, turns on looping. loop 0 turns off looping. By default, looping is off.
open file-type [symbol]
filename [symbol]
In left inlet: Opens a file for recording. By default, the file type is AIFF, but sfrecord~ also supports NeXT/Sun, and WAV formats. The word open without a filename argument brings up a standard Save As dialog allowing you to choose a filename. The optional symbols aiff, au, raw, or wave specify the file format (which can also be set in the Save As dialog with a Format pop-up menu). If open is followed by another symbol, it creates a file in the current default volume. An existing file with the same name will be overwritten. The format symbol (e.g., aiff) can follow the optional filename argument.
nchans number-of-channels [int]
The word nchans, followed by a number in the range 1-28, sets the number of channels for the audio file to be recorded. The default is 1.
print Outputs cryptic status information about the progress of the recording.
record recording-time (milliseconds) [float]
In left inlet: If a file has been opened with the open message, the word record, followed by a time in milliseconds, begins recording for the specified amount of time. The recording can be stopped before it reaches the end by sending sfrecord~ a 0 in its left init.
samptype sample-type [symbol]
bit-depth [int]
In left inlet: The word samptype, followed by a symbol, specifies the sample type to use when recording the audio file (thus overriding the audio file's actual sample type). This is sometimes called "header munging." When reading files in response to the openraw message, the assumed sample type is 16-bit integer.

The following types of sample data are supported:

int8: 8-bit integer
int16: 16-bit integer
int24: 24-bit integer
int32: 32-bit integer
float32: 32-bit floating-point
float64: 64-bit floating-point
mulaw: 8-bit "mu"-law encoding
alaw: 8-bit a-law encoding
resample sampling-rate-coefficient [float]
The word resample, followed by a float, will upsample or downsample the file. Sample rates are expressed as floating-point values - 1.0 is the current sampling rate, 0.5 is half the current, 2.0 is twice the current sample rate, etc.
signal Each inlet of sfrecord~ accepts a signal which is recorded to a channel of an audio file when recording is turned on.

Information for box attributes common to all objects


signal: The time, in milliseconds, since recording of the file began. If recording has stopped, the signal value will remain at the length of the last recording until a new recording is started.


Save an audio file containing 'real world' sound and/or sound created in MSP

See Also

Name Description
sfplay~ Play audio file from disk
MSP Tutorial 16: Record and Play Audio Files MSP Tutorial 16: Record and Play Audio Files