Hitcachi TV is showing all purple and green color on the pictures

My Hitachi ultravision 60 inch TV is suddenly showing all purple and green colors on the upper half of the screen. They are not running lines but more like the pictures are painted over by purple and greens and they look like there is  a shadow of the picture above the actual picture.  I tried the auto convergence/auto focus feature but it did not help.  Can someone tell me if this kind of problem can be fixed by ourselves  or should we call a trained technician. Any ideas how much would it cost to get it fixed.

thanks in advance

varsha