With this mode enabled, the MPEG decoder uses a different algorithm for interlaced frames so that the
4:2:0 format chroma interlacing is preserved.
+\section{DVD with LPCM audio}%
+\label{sec:dvd_lpcm_audio}
+
+By default, the audio when creating a DVD is always \textit{AC3}. However you can switch to \textit{PCM} (Pulse Code Modulator) with just a few additional steps as outlined below.
+Note that Audio must be $48Khz$ or $96Khz$, nothing else is supported, even by ffmpeg's dvd pcm encoder.
+
+\begin{enumerate}
+ \item Start \CGG{} from a terminal window so you will be able to see what is happening. Only the final step when you actually want to write to a
+DVD media writer, requires privileges of either root or the system has
+granted the user this privilege.
+ \item Make sure you have your video with audio loaded and edited to your satisfaction and you are positioned at the start of the video.
+ \item Use the \texttt{File} pulldown and select the \textit{DVD Render} option.
+ \item In the\textit{Create DVD} window, accept the defaults or select different values and then click \texttt{OK}. Do not check "Use FFMPEG" as that will not work.
+ \item When the \textit{Batch Render} window pops up, in the big box towards the bottom will be 2 lines with the first line for \textit{Video} already highlighted. Instead, click on the second line, which is for \textit{Audio}, so that it is highlighted.
+ \item On the top left, you will see the \textit{File Format} set as AC3. Use the down arrow next to the box and change it to \textit{Raw PCM} by clicking on it.
+ \item When you switch to Raw PCM, you see the extension in the \texttt{Output path} above change to pcm
+ instead of ac3. Now just reset the extension from pcm to lpcm as that is required. In most cases if you click on the \texttt{Audio} wrench to see the settings, you will find that the standard settings of 16 bit Linear / Signed / Hi Lo work. If not, experiment for alternatives.
+ \item Now click on the \texttt{Start} box in the bottom left hand corner and \CGG{} will process what it can of the job and put you back at your terminal startup window.
+ \item You will see a few lines of output, some of which are shown below, to include the ERROR:
+ \begin{lstlisting}[style=sh]
+ running /dev/shm//dvd_20240116-182336/dvd.sh
+ INFO: [mplex] mplex version 2.1.0 (2.2.7 $Date: 2012/11/17 01:55:16 $)
+ **ERROR: [mplex] Unable to open file
+ /dev/shm/dvd_20240116-182336/dvd.ac3 for reading.
+ \end{lstlisting}
+ \item Change directory to the location as shown on the terminal window of \texttt{dvd.sh}.
+ \item Using an editor, modify the line in dvd.sh to change \texttt{dvd.ac3} to \texttt{dvd.lpcm} and change the mplex parameter to include:
+ \begin{lstlisting}[style=sh]
+ -L 48000:2:16
+ \end{lstlisting}
+ The full line will look like this:
+ \begin{lstlisting}[style=sh]
+ mplex -f 8 -L 48000:2:16 -o $dir/dvd.mpg $dir/dvd.m2v $dir/dvd.lpcm
+ \end{lstlisting}
+ \item Now the script is ready to run in the same manner it would have had it been ac3. That is just run via:
+ \begin{lstlisting}[style=sh]
+ ./dvd.sh
+ \end{lstlisting}
+ \item Check to make sure there are no errors in the output shown on the window and proceed as usual.
+\end{enumerate}
+
+
\section{MPEG utility programs}%
\label{sec:mpeg_utility_programs}