export CIN_HW_DEV=vaapi
\end{lstlisting}
+In addition for a computer with dual graphics cards, you can select your specific device with an environment variable
+to decode and encode. For example:
+\begin{lstlisting}[numbers=none]
+CIN_DRM_DEC=/dev/dri/renderD129 CIN_DRM_ENC=/dev/dri/renderD128 ./cin
+\end{lstlisting}
+and substituting your specific location instead of /dev/dri/renderD129 or D128.
+
It might be more difficult to analyze problems as a result of using the GPU because of the wide variation in hardware. When you do not set the \texttt{CIN\_HW\_DEV} environment variable, the code will work exactly as before since this feature is self-contained.
There is also a \texttt{Settings $\rightarrow$ Preferences, Performance} tab, \textit{Use HW device} flag