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\section{Interfacing the Tools}
\subsection{Files and Pipes}
The first versions of these tools used files and pipes to exchange data. For
offline generation of a multiplex or a modulated I/Q, it is possible to
generate all files separately, one after the other.
Here is an example to generate a two-minute ETI file for a multiplex containing two programmes:
\begin{itemize}
\item one DAB programme at 128kbps, encoded with toolame-dab
\item one \dabplus{} programme at 88kbps, encoded with fdk-aac-dabplus
\end{itemize}
We assume that the audio data for the two programmes is located in uncompressed
48kHz WAV in the files \filename{prog1.wav} and \filename{prog2.wav}. The first step
is to encode the audio. The DAB programme is encoded to \filename{prog1.mp2} using:
\begin{lstlisting}
toolame -b 128 prog1.wav prog1.mp2
\end{lstlisting}
The DAB+ programme is encoded to \filename{prog2.dabp}. The extension
\filename{.dabp} is arbitrary, but since the framing is not the same as for
other AAC encoded audio, it makes sense to use a special extension. The command
is:
\begin{lstlisting}
dabplus-enc -i prog2.wav -b 88 -a o prog2.dabp
\end{lstlisting}
These resulting files can then be used with ODR-DabMux to create an ETI file.
ODR-DabMux supports many options, which makes it much more practical to set
the configuration using a file than using very long command lines. Here is a short
file that can be used for the example, which will be saved as \filename{2programmes.mux}:
\begin{lstlisting}
general {
dabmode 1
nbframes 5000
}
remotecontrol { telnetport 0 }
ensemble {
id 0x4fff
ecc 0xec ; Extended Country Code
local-time-offset auto
international-table 1
label "mmbtools"
shortlabel "mmbtools"
}
services {
srv-p1 { label "Prog1" }
srv-p2 { label "Prog2" }
}
subchannels {
sub-p1 {
type audio ; MPEG
inputfile "prog1.mp2"
bitrate 128
id 10
protection 5
}
sub-p2 {
type dabplus
inputfile "prog2.dabp"
bitrate 88
id 1
protection 1
}
}
components {
comp-p1 {
label Prog1
service srv-p1
subchannel sub-p1
}
comp-p2 {
label Prog2
service srv-p2
subchannel sub-p2
}
}
outputs { output1 "file://myfirst.eti?type=raw" }
\end{lstlisting}
This file defines two components, that each link one service and one
subchannel. The IDs and different protection settings are also defined.
The bitrates defined in the subchannels must correspond to the bitrate set at the encoder.
The duration of the ETI file is limited by the \lstinline{nbframes 5000} setting. Each frame
corresponds to $24$\ms, and therefore $120 / 0.024 = 5000$ frames are needed
for $120$ seconds.
The output is written to the file \filename{myfirst.eti} in the ETI(NI) format. Please
see Appendix~\ref{etiformat} for more options.
To run the multiplexer, run:
\begin{lstlisting}
odr-dabmux -e 2programmes.mux
\end{lstlisting}
This will generate the file \filename{myfirst.eti}, which will be $5000 * 6144
\approx 30$\si{MB} in size.
Congratulations! You have just created your first DAB multiplex! With the configuration file,
adding more programmes is easy. More information is available in the \filename{doc/example.mux}
\subsection{Over the Network}
\subsubsection{Authentication Support}
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