Using Gstreamer with OpenMax in a Raspberry Pi

This minipost shows a subgroup of commands tested in a Raspberry Pi to evaluate the possibilities of a usage of this hardware as a domestic TV Headend.

  • From UDP/TS source with video MPEG2 to another UDP multicast group transcoding the video
    stream with H264:gst-launch-1.0 -v  udpsrc uri=udp://239.123.123.3:1234 ! tsdemux ! queue ! mpegvideoparse ! omxmpeg2videodec ! videoconvert ! omxh264enc ! video/x-h264,stream-format=byte-stream,profile=high ! h264parse ! mpegtsmux ! udpsink host=239.123.124.3 port=1234 auto-multicast=true

    The Gstreamer pipeline doesn’t break/end but there is a bug in the h264parse: it sends not regularly the needed SPS / PPS information with it (http://www.raspberrypi.org/forums/viewtopic.php?f=70&t=59412). Then, resulting stream is only playable if you get the stream from the beginning.

  • From UDP/TS source with video MPEG2 and MP2 to another UDP multicast group transcoding the video stream with H264 and video with AAC:
    gst-launch-1.0 -v udpsrc uri=udp://239.123.123.1:1234 ! queue ! tsdemux name=dem \
    dem. ! queue ! mpegvideoparse ! mpeg2dec ! videoconvert ! omxh264enc control-rate=1 target-bitrate=1000000 ! video/x-h264,stream-format=byte-stream,profile=high ! h264parse config-interval=2 ! queue ! muxer. \
    dem. ! queue ! mpegaudioparse ! mpg123audiodec ! audioconvert ! faac ! queue ! muxer. \
    flvmux name=muxer ! queue ! rtmpsink location="rtmp://rtmp.server:1935/rtmp/test2 live=test2"

    The Gstreamer pipeline breaks for some unkknown reason.

  • From UDP/TS source with video MPEG2 to a RTMP server transcoding to H264:
    gst-launch-1.0 -v udpsrc uri=udp://239.123.123.1:1234 ! queue ! tsdemux name=dem \
    dem. ! queue ! mpegvideoparse ! mpeg2dec ! videoconvert ! omxh264enc control-rate=1 target-bitrate=1000000 ! video/x-h264,stream-format=byte-stream,profile=high ! h264parse config-interval=2 ! queue ! muxer. \
    flvmux name=muxer ! queue ! rtmpsink location="rtmp://rtmp.server:1935/rtmp/test2 live=test2"

    Works fine and smooth. Source is a MPEG/TS SD channel.

  • From UDP/TS source with audio MP2 to a RTMP server transcoding audio channel to AAC:
    gst-launch-1.0 -v udpsrc uri=udp://239.123.123.1:1234 ! queue ! tsdemux name=dem \
    dem. ! queue ! mpegaudioparse ! mpg123audiodec ! audioconvert ! faac ! queue ! muxer. \
    flvmux name=muxer ! queue ! rtmpsink location="rtmp://rtmp.server:1935/rtmp/test2 live=test2"

    Works fine and smooth.

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