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Graphic Memory Formats

This appendix describes the various formats in which pixel information is stored in frame buffers in PCI-based Power Macintosh computers. It also includes information about transforming pixel information to convert it from big-endian to little-endian format and vice versa. For information about data formats, see Big-Endian and Little-Endian Addressing

The drawings in this appendix that illustrate pixel formats are presented in three parts:

• The top diagram (denoted by BIG) shows the pixel's big-endian format, with the byte lanes numbered in big-endian order.
• The middle diagram (denoted by GIB) shows the pixel value as it appears on the PCI bus, byte swapped to fulfill the PCI bridge's address invariance. This diagram shows the little-endian PCI byte lane numbering.
• The bottom diagram (denoted by LITTLE) shows the little-endian format, with the byte lanes numbered in little-endian order.

RGB Pixel Formats

YUV Pixel Formats

Definitions of Pixel Formats in C