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Chapter 3 - Image Compression Manager / Image Compression Manager Reference

Image Compression Manager Functions / Changing Sequence-Compression Parameters

SetCSequenceFlushProc

The SetCSequenceFlushProc function lets you assign a data-unloading function to a sequence.

pascal OSErr SetCSequenceFlushProc (ImageSequence seqID,
                                    FlushProcRecordPtr flushProc,
                                    long bufferSize);

seqID

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

flushProc

Points to a data-unloading function structure. If there is not enough memory to store the compressed image, the compressor calls a function you provide that unloads some of the compressed data (see "Data-Unloading Functions" beginning on page 3-144 for more information on the data-unloading structure). If you have not provided a data-unloading function, set this parameter to nil. In this case, the compressor writes the entire compressed image into the memory location specified by the data parameter to the CompressSequenceFrame function (described on page 3-105).

bufferSize

Specifies the size of the buffer to be used by the data-unloading
function specified by the flushProc parameter. If you have not specified a data-unloading function, set this parameter to 0.

DESCRIPTION

Data-unloading functions allow compressors to work with images that cannot fit in memory. During the compression operation, the compressor calls the data-unloading function whenever it has accumulated a specified amount of compressed data. Your data-unloading function then writes the compressed data to some other device, freeing buffer space for more compressed data. The compressor starts using the data-unloading function with the next image in the sequence. See "Spooling Compressed Data" on page 3-44 for more information.

There is no parameter to the CompressSequenceBegin function (described on page 3-100) that allows you to assign a data-unloading function to a sequence.

RESULT CODES

noErr	0	No error
paramErr	-50	Invalid parameter specified