README - updates for samples (#98)

* update readme for samples

* readme clean up

* readme clean up

samples/videoDecodePerf/README.md

@@ -1,7 +1,5 @@
 # Video Decode Sample
-This sample illustrates the FFMPEG demuxer to get the individual frames which are then decoded on AMD hardware using VAAPI.
-
-This sample supports both YUV420 8-bit and 10-bit streams. 
+This sample illustrates the FFMPEG demuxer to get the individual frames which are then decoded on AMD hardware using rocDecode library.
 
 This sample uses multiple threads to decode the same input video parallely.
 
@@ -34,4 +32,6 @@ make -j
 ```
 ./videodecodeperf -i <input video file [required]> 
                   -t <number of threads [optional - default:4]>
+                  -d <Device ID (>= 0) [optional - default:0]>
+                  -z <force_zero_latency - Decoded frames will be flushed out for display immediately [optional]>
 ```