QuickTime 3 Reference
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QuickTime has permitted compressed image data to be included in QuickDraw pictures since QuickTime 1.0. However, the technical challenges of parsing, interpreting and spooling picture files can make them a discouraging choice for applications which are primarily interested in accessing the compressed data inside. Determining if compressed data is present, and extracting it, requires special code installed in QuickDraw bottlenecks to detect and copy compressed data as it processes. Additional problems are posed by special cases such as multiple compressed images in a single file.
The QuickTime Image file format (QTIF) provides a much simpler container for compressed still images. The format uses the same atom-based structure as a QuickTime movie. (See Chapter 1, "Movie Toolbox," in this reference guide for information about atoms.) Because the QuickTime Image file is a single fork format, it works well in cross-platform applications. On Mac OS systems, QuickTime Image files are identified by the file type 'qtif' . On other platforms, Apple recommends that you use the filename extension .QIF to identify QuickTime Image files.
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