Performance results for libjpeg-turbo

Awesome performance gain with libjpeg-turbo !!! It performs significantly faster than the older libjpeg62 / libjpeg8 implementation. I used the jpeg test app in v4l4j and here are the conversion timings for both libjpeg62 and libjpeg-turbo8

The table below shows the average conversion times over 10 runs for a 1280x1024 image in various YUV source format. Tests were run from a VM running Ubuntu 12.04 Precise beta1, so the conversion time itself does not mean much, but what's interesting is the comparison between the two implementations. In my tests, the turbo implementation was 3x to 4x faster.

	libjpeg-turbo8	libjpeg62
YUYV to JPEG	5.5 ms	21.5 ms
UYVY to JPEG	5.7 ms	21.1 ms
YVYU to JPEG	6.8 ms	22.0 ms
YUV420p to JPEG	3.8 ms	15.6 ms
ARGB to JPEG	4.6 ms	16.4 ms
RGB24 to JPEG	4.6 ms	16.4 ms
BGRA to JPEG	4.6 ms	16.4 ms
BGR24 to JPEG	4.9 ms	16.4 ms