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Chapter 3 - Image Compression Manager / Image Compression Manager Reference

Image Compression Manager Functions / Changing Sequence-Decompression Parameters

SetDSequenceMatrix

The SetDSequenceMatrix function assigns a mapping matrix to the sequence.

pascal OSErr SetDSequenceMatrix (ImageSequence seqID,
                                  MatrixRecordPtr matrix);

seqID

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

matrix

Points to a matrix structure that specifies how to transform the image during decompression. You can use the matrix structure to translate or scale the image during decompression. To set the matrix to identity, pass nil in this parameter. See the chapter "Movie Toolbox" in this book for more information about matrix operations.

DESCRIPTION

The decompressor uses the matrix to create special effects with the decompressed image, such as translating or scaling the image. The new matrix takes effect with the next frame in the sequence.

RESULT CODES

noErr	0	No error
paramErr	-50	Invalid parameter specified

SEE ALSO

You set the default matrix for a sequence with the matrix parameter to the DecompressSequenceBegin function.