The best format and data type combinations to use for texture data are:
GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV
GL_BGRA, GL_UNSIGNED_SHORT_1_5_5_5_REV)
GL_YCBCR_422_APPLE, GL_UNSIGNED_SHORT_8_8_REV_APPLE
The combination GL_RGBA and GL_UNSIGNED_BYTE needs to be swizzled by many cards when the data is loaded, so it's > not recommended.
Originally posted by @ccawley2011 in #11889 (comment)
It would be interesting to know that's true for modern Macs, and if it's worth prioritising it for SDL's OpenGL renderer on Mac OS X.