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Chapter 3 - Image Compression Manager / Image Compression Manager Reference

Image Compression Manager Functions / Constraining Compressed Data

SetCSequenceDataRateParams

The SetCSequenceDataRateParams function allows your application to set parameters in the data rate parameters structure, which communicates information to compressors that can constrain compressed data in a particular sequence to a specific data rate.

pascal OSErr SetCSequenceDataRateParams
                           (ImageSequence seqID,
                            DataRateParamsPtr params);

seqID

Contains the unique sequence identifier that was returned by the CompressSequenceBegin function (described on page 3-100).

params

Points to the data rate parameters structure to be associated with the sequence identifier specified in the seqID parameter.

DESCRIPTION

If your application is keeping track of data overrun, you should call the SetCSequenceDataRateParams function before each use of the CompressSequenceFrame function (described on page 3-105). If not, you only need to call SetCSequenceDataRateParams before the first use of CompressSequenceFrame, with the dataOverrun parameter of the data rate parameters structure set to 0. In this case, it is assumed that the frame duration is valid for all frames. Setting the dataRate field in the data rate parameters structure to 0 is the same as not performing data rate constraint.

RESULT CODES

noErr	0	No error
paramErr	-50	Invalid parameter specified