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Chapter 5 - Sequence Grabber Components / Sequence Grabber Components Reference

Sequence Grabber Component Functions / Working With Sound Channels

SGSetSoundRecordChunkSize

During record operations, the sequence grabber works with groups of sound samples. These groups are referred to as chunks. By default, each chunk contains two seconds of sound data. Smaller chunks use less memory. You can control the amount of sound data in each chunk by calling the SGSetSoundRecordChunkSize function.

pascal ComponentResult SGSetSoundRecordChunkSize (SGChannel c,
                                                   long seconds);

c

Specifies the reference that identifies the channel for this operation. You obtain this reference from the SGNewChannel function, described on page 5-29.

seconds

Specifies the number of seconds of sound data the sequence grabber is to work with at a time. To specify a fraction of a second, set this parameter to a negative fixed-point number. For example, to set the duration to half a second, pass in -0.5 in this parameter.

DESCRIPTION

You specify the number of seconds of sound data the sequence grabber is to work with at a time.

SPECIAL CONSIDERATIONS

You cannot call the SGSetSoundRecordChunkSize function during a record or preview operation, or after you have prepared the sequence grabber for a record
or preview operation (by calling the SGPrepare function, described on page 5-40).

This function may return a fraction (for details, see the discussion of the seconds parameter above).

RESULT CODES

paramErr	-50	Invalid parameter specified
cantDoThatInCurrentMode	-9402	Request invalid in current mode