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Cookbook : Separating out lots of channels from a recorded DVB broadcast

Find this code here:
/Code/Python/Kamaelia/Examples/DVB_Systems/TransportStreamDemuxer.py

This simple example shows how to read back in a recorded transport stream from a file and separate out (demultiplex) several channels from it:

from Kamaelia.Device.DVB.Core import DVB_Demuxer
from Kamaelia.File.ReadFileAdaptor import ReadFileAdaptor
from Kamaelia.Chassis.Graphline import Graphline
from Kamaelia.File.Writing import SimpleFileWriter

Graphline(
    SOURCE=ReadFileAdaptor("BBC_MUX_1.ts"),
    DEMUX=DVB_Demuxer({
        640: ["NEWS24"],
        641: ["NEWS24"],
        600: ["BBCONE"],
        601: ["BBCONE"],
        610: ["BBCTWO"],
        611: ["BBCTWO"],
        620: ["CBBC"],
        621: ["CBBC"],
        18:  ["NEWS24", "BBCONE"],# "BBCTWO", "CBBC"],
    }),
    NEWS24=SimpleFileWriter("news24.data"),
    BBCONE=SimpleFileWriter("bbcone.data"),
    BBCTWO=SimpleFileWriter("bbctwo.data"),
    CBBC=SimpleFileWriter("cbbc.data"),
    linkages={
       ("SOURCE", "outbox"):("DEMUX","inbox"),
       ("DEMUX", "NEWS24"): ("NEWS24", "inbox"),
       ("DEMUX", "BBCONE"): ("BBCONE", "inbox"),
       ("DEMUX", "BBCTWO"): ("BBCTWO", "inbox"),
       ("DEMUX", "CBBC"): ("CBBC", "inbox"),
    }
).run()

The DVB_Demuxer component takes, at initialization, a dictionary mapping packet IDs (PIDs) to outbox names. Each of those outboxes has been linked to a SimpleFileWriter component to write it to a file.

For all the channels there are two PIDs - one for the audio and one for the video. For two of them, we also include PID 18 which carries Event Information Tables (tables containing now & next and EPG data)