All Databases Inside Mac - Sound Mgr

SPBRecord

Record audio data into memory

#include <SoundInput.h> Sound Manager

OSErr SPBRecord( inParamPtr, asynchFlag);

SPBPtr * inParamPtr; a pointer to a sound input parameter block

Boolean asynchFlag; TRUE=Record asynchronously

returns Error Code; 0=no error

You can use the SPBRecord function to record audio data directly from a

sound input device into memory, either synchronously or asynchronously.

SPBRecord does not present the sound input dialog box to the user.

inParamPtr SPBRecord accepts a sound input parameter block , SPB, to

control the recording process. The following fields are relevant:

Out-In Name Type Size Offset Description

Æ inRefNum long 4 0 input device reference number

´ count long 4 4 number of bytes to record

´ milliseconds long 4 8 number of milliseconds to record

Æ bufferLength long 4 12 length of buffer

Æ bufferPtr long 4 16 address of buffer

Æ completionRoutine long 4 20 pointer to completion routine

Æ interruptRoutine long 4 24 pointer to interrupt routine

Æ userLong long 4 28 for application's use

¨ error short 2 32 error returned after recording

Æ unused1 long 4 36 reserved

asynchFlag specifies whether the recording occurs asynchronously.

Returns: an operating system Error Code.

noErr (0) No error

siNoSoundInHardware (-220) No sound input hardware available

siBadSoundInDevice (-221) Invalid sound input device

siNoBufferSpecified (-222) No buffer specified

siDeviceBusyErr (-227) Sound input device is busy

Notes: SPBRecord starts recording into memory from a specified device. The

sound data recorded is simply stored in the buffer indicated, so it is up to

your application to insert whatever headers are needed to play the sound

with the Sound Manager. The asynchFlag parameter specifies whether the

recording occurs asynchronously.

SPBRecord accepts a sound input parameter block , SPB, to control the

recording process. The inRefNum field of the parameter block should contain

the reference number of the device to record from. The count field contains

the number of bytes to record and the milliseconds field contains the

number of milliseconds to record. If one of these fields specifies a longer

recording time than the other, then the longer time is used and both fields

are updated to reflect the actual amount recorded.

The bufferPtr field points to the buffer to record into, and the

bufferLength field gives the length (in bytes) of that buffer. The recording

times given in the count and milliseconds fields are always truncated to the

size of this buffer, if necessary. If the bufferPtr field contains NULL, then

the count, milliseconds, and bufferLength fields are ignored, and the

recording continues indefinitely until you call SPBStopRecording. If

bufferPtr is NULL, the audio data is not saved anywhere; this feature is

useful only if you want to do something in your interrupt routine and do not

want to save the audio data. If the recording is synchronous and bufferPtr is

NULL, SPBRecord returns the result code siNoBufferSpecified.

The completion routine specified in the completionRoutine field is called

when the recording terminates (either when you call SPBStopRecording

or when the prescribed limit is reached). The completion routine is called

only for asynchronous recording.

The interrupt routine specified in the interruptRoutine field is called by

asynchronous recording devices when their internal buffers are full.

You can set the userLong field to any value. The error field contains a value

greater than 0 while recording occurs. When recording terminates without

an error, the error field is set to 0. If an error occurs during the

recording, the error field will contain a value that is less than 0 and is of

type OSErr.

Note: If more than one channel is being recorded, the samples are

interleaved into the buffer.

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