| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |
Arguments: device &key bits-per-sample samples-per-second channels notify-p wait-p
Sets the audio quality and other options for recording a wave file. This function is necessary for decent quality audio in MCI, since the default quality is rather low.
Each of the options bits-per-sample,
samples-per-second, and
channels may be either nil
to not modify that attribute, or else an integer
indicating a new value for that attribute. The values that have a
desirable effect may depend on the sound card's driver, and it is not
clear how to determine programmatically what values will work well.
bits-per-sample is the number of bits used to store each sample. The default is 8 (low quality). 16 is audio-CD quality and is recommended.
samples-per-second is the number of samples that are recorded for each second of sound. The default is 11025 (low quality). A common high-quality sampling resolution that has worked well in our brief tests on a basic sound card is 48000. Audio CDs use 44100, though in our tests on a basic sound card this value did not produce high-quality audio (perhaps the proper value is not exactly 44100). Some applications that burn audio CDs require that the wave file already be in 16-bit, 44.1k resolution format though.
channels (when non-nil
)
may be either 1 for a monophonic recording or 2 for a stereo
recording.
If this function is called, it must be called before any recording is done on the device, or after mci-delete is called to erase everything that has been recorded on the device.
device is an mci-wave-audio
instance. If
wait-p is true, then this function does not
return until the operation is complete; otherwise the function returns
immediately and the operation is performed asynchronously. If
notify-p is true, then mci-notify is called when the
operation has completed.
See the sample recording session at mci-record for more information.
See cg-mci.htm for information about MCI support in Common Graphics.
Copyright (c) 1998-2016, Franz Inc. Oakland, CA., USA. All rights reserved.
This page was not revised from the 8.1 page.
Created 2010.1.21.
| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |