Hi Anoop,
Thanks for the detailed documentation on this and sorry for the delay. By the sounds of it, regardless of whether you use the data from your processor or whether you use the internal test pattern, the image is being cropped at the left and right side of the image. Is it also being cropped at the top and bottom? It sounds like this is an issue with the display. Have you tried using a TV instead of a PC monitor? It could be something with the over-scan or the aspect of the monitor.
Could you measure the active video length on a 'scope that will tell you for definite if the analog output timing is correct.
Regards,
Paul