I have just recently flash a TX2 with JP 4.2 and inspect the GStreamer plugins looking for the MPEG-TS support related elements, it seems that they are enabled by default.
nvidia@nvidia:~$ gst-inspect-1.0 | grep mpegts
libav: avmux_mpegts: libav MPEG-TS (MPEG-2 Transport Stream) muxer (not recommended, use mpegtsmux instead)
typefindfunctions: video/mpegts: ts, mts
mpegtsdemux: tsparse: MPEG transport stream parser
mpegtsdemux: tsdemux: MPEG transport stream demuxer
mpegtsmux: mpegtsmux: MPEG Transport Stream Muxer
If the plugins don’t appear at all, you should try installing the gstreamer-plugins-bad package as follows:
sudo apt-get install gstreamer1.0-plugins-bad
If the package can´t be found, you should modify the “/etc/apt/sources.list” file by uncommenting the lines to get access to more packages repositories.
On the following link you can find some GStreamer MPEG2 TS example pipelines: