mxfmux : Mxfmux is not functional with splitmuxsink

Submitted by Baby octopus

Link to original bug (#788827)

Description

There are two issues

1. Pad templates of mxfmux is not generic like that of mp4. Splitmuxsink does't have support for such pad templates(ex: mpeg_audio_sink_%u). Its good to have generic pad template such as audio_%d, video_%d etc
2. With workaround for above issue(hardcoding in splitmuxsink), I tried to run a pipeline to fragment filed and mux them into MXF. Issue happens during the creation of second fragment. EOS isn't handled properly I guess which is leading to crash.

Here is the pipeline
gst-launch-1.0 videotestsrc is-live=1 ! video/x-raw,format=I420 ! x264enc ! splitmuxsink muxer=mxfmux location=/root/out_%d.mxf max-size-time=4000000000

ERROR:mxfmux.c:1571:gst_mxf_mux_handle_eos: assertion failed: (mux->offset == body_partition)

Version: 1.12.1