My simple transcoding app hangs, code review requested

[Andrey Utkin]

I have build equivalent gst-launch command line, but it hangs in the same way:

gst-launch-1.0 filesrc
location=/home/krieger/Downloads/big_buck_bunny_720p_h264.mov !
qtdemux name=demux demux.audio_0 ! queue ! avdec_aac ! audioconvert !
avenc_mp2 ! queue ! mpegtsmux name=mux mux. ! filesink
location=bbb_reenc.ts  demux.video_0 ! queue ! avdec_h264 !
videoconvert ! x264enc ! queue ! mux.

Setting pipeline to PAUSED ...
Pipeline is PREROLLING ...
Redistribute latency...
Redistribute latency...


I've read that some options tuning for queues may help.
How exactly should i tune it?

-- 
Andrey Utkin