Yes! I managed to get gst-launch OMX-transcoding a DVB-C MPEG2-stream to 2 mb/s to a file, I saw it work fully with the RPi1 and RPi3 with MPEG2-license. With the RPi2 I saw it work until the need of a MPEG2-license (which I didn't buy yet for this second hand RPi2), but the main demuxer worked there as well.
I saw synchronous audio and video (I had to absolutely minimize the software-transcoding of audio to get it work)
I needed no compiling, just installing, so no need for the transcoding compiled into TVHeadend and even no difficult selection of an audio stream.
I used berryboot and raspbian Jessie because berryboot makes the image interchangable between RPi1, 2 and 3 and installs the root filesystem on a USB3-stick that makes installing and upgrading twice as fast.
Steps:
Get the actual berryboot image of Raspbian Jessie (I got the initially offered 2016-7-27 version)
sudo apt-get update
sudo apt-get upgrade
(Berryboot doesn't update the boot-kernel during this procedure, but that doesn't matter)
Get all packages for gstreamer (I don't know if this installs unnecessary packages as well)
sudo apt-get install gstreamer1.0
sudo apt-get install gstreamer-1.0
Follow
https://tvheadend.org/d/3969-unofficial-raspberry-pi-armhf-builds for installing tvheadend. For the RPi1 there is a special dpkg-instruction on page 2, as the right armv6hf-package doesn't come with apt-get:
dpkg -i tvheadend_4.1-2332-g38c9e89_armhf.deb
Make tvheadend tune the channels, or just copy the /home/hts/.hts tree from some working TVHeadend-install.
En then the magic:
gst-launch-1.0 souphttpsrc location="http://127.0.0.1:9981/stream/channel/41ceb7b6ef96f869d7d6c78b6b3a27a6?ticket=24A946694272F14A9994F5F2280E466AB495F745?profile=pass" num-buffers=-1 ! tsdemux name=demux demux. ! queue ! mpegvideoparse ! omxmpeg2videodec ! videoconvert ! omxh264enc target-bitrate=2097152 control-rate=variable ! video/x-h264,stream-format=byte-stream,profile=high,width=720,height=576,framerate=25/1 ! h264parse ! mux. mpegtsmux name=mux ! filesink location=robert.mp4 demux. ! queue ! mpegaudioparse ! mux.
To get the aspect-ratio 16:9 right I had to use VLC which only was able to show this file correctly after resetting the settings.
I guess the last step, streaming over the network, will be a smaller one now.
As soon as I got that working I'll also have a look at the transcoding in TVHeadend earlier in this thread.
The quality of this OMX decoding/coding appears to be good enough to invest some more time in it to get it working straight from TVHeadend.
Gstreamer contains an executable, gst-discoverer-1.0, which can tell you what audio and video-format you need to get your stream decoded.
gst-inspect-1.0 will show you what elements are to be used in the gst-launch pipeline.
