Add gray mode to speed up & input_uvc for autoend task without ctrl-c

[ywz978020607]

1. Add gray mode, to speed up.
2. for some reason, my linux init cam wrongly, but will recover after ctrl-c 1~2 times. But when I use new shell, then I need re-run, so add this to avoid input ctrl-c, which is difficult in popen subprocess.