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Chapter 3 - Image Compression Manager / Image Compression Manager Reference

Image Compression Manager Functions

Changing Sequence-Decompression Parameters

This section discusses the functions that enable your application to manipulate the parameters that control sequence decompression and to get information about memory that the decompressor has allocated. Your application establishes the default value for most of these parameters with the DecompressSequenceBegin function (described on page 3-107). Some of these functions deal with parameter values that cannot be set when starting a sequence.

You can determine the buffers used by a decompressor component when it decompresses a sequence. Use the GetDSequenceImageBuffer function to determine the location of the image buffer. Use the GetDSequenceScreenBuffer function to determine the location of the screen buffer.

You can control a number of the parameters that affect a decompression operation (note that changing these parameters may temporarily affect performance). Use the SetDSequenceAccuracy function to control the accuracy of the decompression. Use the SetDSequenceDataProc function to assign a data-loading function to the operation. Use the SetDSequenceMask function to set the clipping region for the resulting image. You can establish a blend matte for the operation by calling the SetDSequenceMatte function. You can alter the spatial characteristics of the resulting image by calling the SetDSequenceMatrix function. Your application can establish the size and location of the operation's source rectangle by calling the SetDSequenceSrcRect function. Finally, you can set the transfer mode used by the decompressor when it draws to the screen by calling the SetDSequenceTransferMode function.

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Subtopics

SetDSequenceTransferMode

SetDSequenceSrcRect

SetDSequenceMatrix

SetDSequenceMask

SetDSequenceMatte

SetDSequenceAccuracy

SetDSequenceDataProc

GetDSequenceImageBuffer

GetDSequenceScreenBuffer