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<p class="MsoNormal"><span lang="EN-US">Hello, <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I am new to Gstreamer. I wrote a simple RTSP server that generates a pipeline (gst_rtsp_media_factory_set_launch) like :<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">appsrc name=vsrc is-live=true do-timestamp=true ! queue ! h264parse ! rtph264pay name=pay0 pt=96<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">The SDP response is generated after the DESCRIBE request, but only after a few frames on the signal have been received by the appsrc input:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">vsrc = gst_bin_get_by_name_recurse_up(GST_BIN(element), "vsrc"); // appsrc<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">if (nullptr != vsrc)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">{<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas"> gst_util_set_object_arg(G_OBJECT(vsrc), "format", "time");<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas"> g_signal_connect(vsrc, "need-data", (GCallback)need_video_data, streamResource);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">}<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">The time from which the video is to be played is passed in the RTSP request PLAY, in the Range header as an absolute:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">PLAY rtsp://172.19.9.65:554/Recording/ RTSP/1.0<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">CSeq: 4<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">Immediate: yes<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">Range: clock=20220127T082831.039Z- // Start from ...<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">To the object GstRTSPClient attached the handler to the signal in which I process this request and make the move to the right time in my appsrc<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">g_signal_connect(client, "pre-play-request", (GCallback)pre_play_request, NULL);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">The problem is that at this point my appsrc's start time frames have already arrived in pipline and I watch them first, and then the playback continues from the time specified in the PLAY request (after seek in my appsrc).
Can you please tell me how I can cut off these initial frames that came in before the PLAY call.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I've tried:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">1. gst_element_seek - doesn't help because of peculiarities of appsrc implementation<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">2. Flush didn't help either, tried resetting sink at element rtph264pay:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">gst_pad_push_event(sinkPad, gst_event_new_flush_start());<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">GST_PAD_STREAM_LOCK(sinkPad);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">// ... seek in my appsrc<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">gst_pad_push_event(sinkPad, gst_event_new_flush_stop(TRUE));<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">GST_PAD_STREAM_UNLOCK(sinkPad);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas">gst_object_unref(sinkPad);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Thank You!</span></p>
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