I can enable picture loss indication if my media factory creates following pipeline:
videotestsrc is-live=True ! video/x-raw,width=640,height=480,framerate=30/1,format=NV12 ! x264enc tune=zerolatency speed-preset=superfast ! h264parse ! rtph264pay pt=96 ! capsfilter caps="application/x-rtp,rtcp-fb-nack-pli=\(boolean\)1" name=pay0
with this SDP shows:
a=rtcp-fb:96 nack pli
This does not seem to fulfill the assumption of having payloader as the last element of the pipeline, i.e. RTSP server expects to find property “pt” from element named pay0:
Warning: g_object_get_is_valid_property: object class 'GstCapsFilter' has no property named 'pt'
What is the proper way of enabling PLI?