fix endianness comparison (#397)
fix endianness comparison (#397)

Fix endianness comparison between source and platform, when source
is little endian and platform is big endian, they are different too.

Co-authored-by: zhouchengming <79befeb9e63ca677bd0cc83c044a829bd4c7c026@cainiao.com>
ros-perception/vision_opencv,ros-perception/vision_opencv,ros-perception/vision_opencv,ros-perception/vision_opencv