omxh264 enc and qtmux

Tonu Jaansoo tonu at innotal.com
Thu Sep 8 12:44:04 UTC 2016


Hi! 

I wanted to ask if omxh264enc is usable to mux h264 stream with qtmux on RPi? I want to stream HTML5 compatible H264/AAC stream in qt cotainer. Muxing into TS works, but this is not what I want.

I have pipeline like this: 
videotestsrc is-live=true ! video/x-raw,width=1280,height=720,framerate=30/1 ! omxh264enc ! h264parse ! qtmux ! fakesink
qtmux needs codec_data cap and this cap is not coming from h264parse. So pipeline doesnt get linked.

gst-plugins-good-1.9.2/gst/isomp4/gstqtmux.c:4072 :
    if (!codec_data) {
      GST_WARNING_OBJECT (qtmux, "no codec_data in h264 caps");
      goto refuse_caps;
    }

Alternative way works (not using omxh264enc)
first encode into file using v4l2-ctl:
v4l2-ctl -d /dev/video0 --stream-mmap=3 --stream-count=100000 --stream-to=file.264
then read from this file and feed it -> …! h264parse ! qtmux ! fakesink

So from this I conclude the byte stream is somewhat different between v4l2 encoded and omxh264enc encoded...

Tonu.


More information about the gstreamer-devel mailing list