VSS Video Codec 1.3 Readme file
================================ 

I. VSS Codec utilities
1. AviPsnr.exe

AVIPSNR is a command line tool to calculate PSNR (Peak Signal to Noise Ratio)
between 2 AVI files (frame by frame and total average).
PSNR has been calculated for Y, U, V color planes separately.
The more PSNR value, the less differences between video streams.
	
USAGE:
	AVIPSNR <avifile1> <avifile2> [maxframes]
WHERE:
	avifile1    - first AVI file to compare [MANDATORY];
	avifile2    - second AVI file to compare [MANDATORY];
	maxframes   - number of frames to process [OPTIONAL];

In most applications you don't need to specify optional parameters, they
are needed only when you want to calculate PSNR for some sub-range of
frames inside AVI file.
This utility is a console application and should be run from command line.
USAGE example:
	AVIPSNR movie1.avi movie2.avi
This command will calculate PSNR between movie1.avi and movie2.avi files
and will output resulting value to the screen.

II. Troubleshooting

VSS Video Codec uses DirectX driver. In case of any DirectX problem you should
change 'YUV Output' and 'Enable Overlay' Decoder settings. If the problem persists
you should unregister DirectX filter (regsvr32.exe /u vssv.ax).