YUYV to JPEG conversion with libjpeg

Sharing a small libjpeg snippet.
Some SO questions about it have only partial snippets:

• http://stackoverflow.com/questions/16390783/how-to-save-yuyv-raw-data-to-jpeg-using-libjpeg
• http://stackoverflow.com/questions/17029136/weird-image-while-trying-to-compress-yuv-image-to-jpeg-using-libjpeg
• http://stackoverflow.com/questions/19282402/how-to-compress-a-yuyv-image-into-a-jpeg

Enjoy!
Roy