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Chapter 3 - Image Compression Manager / Image Compression Manager Reference

Image Compression Manager Functions / Changing Sequence-Decompression Parameters

SetDSequenceMask

The SetDSequenceMask function assigns a clipping region to the sequence.

pascal OSErr SetDSequenceMask (ImageSequence seqID, 
                                 RgnHandle mask);

seqID

Contains the unique sequence identifier that was returned by the DecompressSequenceBegin function (described on page 3-107).

mask

Contains a handle to a clipping region in the destination coordinate system. If specified, the decompressor applies this mask to the destination image. If you want to stop masking, set this parameter to nil.

DESCRIPTION

The decompressor draws only that portion of the decompressed image that lies within the specified clipping region. The new region takes effect with the next frame in the sequence. You should not dispose of this region until the Image Compression Manager is finished with the sequence, or until you set the mask either to nil or to a different region by calling the SetDSequenceMask function again.

RESULT CODES

noErr	0	No error
paramErr	-50	Invalid parameter specified

Memory Manager errors

SEE ALSO

You set the default clipping region for a sequence with the mask parameter to the DecompressSequenceBegin function.