Samsung PL64E8000GFXZP - Manual (Page 560)

labeled Pb, Pr, and Y, to connect your
TV and video source, make sure you
have connected the blue Pb jack on
the video source to the blue Pb jack
on the TV, the red Pr jack on the
source to the red Pr jack on the TV.
Screen Brightness
If you find that the colors on your
Samsung TV are correct but just a little
too dark or bright, try adjusting the
following settings in the Picture option