GL_MESA_ycbcr_texture http://www.opengl.org/registry/specs/MESA/ycbcr_texture.txt GL_MESA_ycbcr_texture GL_UNSIGNED_SHORT_8_8_MESA 0x85BA GL_UNSIGNED_SHORT_8_8_REV_MESA 0x85BB GL_YCBCR_MESA 0x8757