<div dir="ltr"><div>I'm using gstreamer 1.0 from python. </div>The gst script is something like: <pre style="background-color:rgb(255,255,255);color:rgb(0,0,0);font-family:"courier new"">default_script = "videotestsrc pattern=smpte is-live=1" " ! timeoverlay" " ! video/x-raw,width=640,height=480,framerate=30/1" " ! x264enc key-int-max=3" " ! tee name = branch" # udp sink "branch." " ! queue silent = true name = queue_stream " " ! rtph264pay config-interval = 1 pt = 96" " ! udpsink host = 192.168.0.12 port = 9000 name = sink_stream" # app sink for capture " branch." " ! queue silent = true max-size-buffers = 1 name = queue_capture " " ! openh264dec" " ! jpegenc" " ! multifilesink location=alma%d.jpg name = capture_sink </pre><pre style="background-color:rgb(255,255,255);color:rgb(0,0,0);font-family:"courier new"">Pad-probes are to drop data on the multifilesink branch like this. First a wait for wait-preroll probe, than an dropp buffer probe is added: </pre><pre style="background-color:rgb(255,255,255);color:rgb(0,0,0);font-family:"courier new""> def pad_data_probe_preroll_capture(pad, info, cam): <a href="http://log.info">log.info</a>("preroll capture") queue = cam._pipeline.get_by_name("queue_capture") pad = queue.get_static_pad("sink") pad.add_probe(Gst.PadProbeType.BUFFER, pad_data_probe_capture, cam) return Gst.PadProbeReturn.REMOVE def pad_data_probe_capture(pad, info, cam): if cam._capture_counter.acquire(False): <a href="http://log.info">log.info</a>("enable data, capture") return Gst.PadProbeReturn.OK else: #<a href="http://log.info">log.info</a>("info drop: {} {}".format(pad, info.get_buffer().dts)) return Gst.PadProbeReturn.DROP queue = self._pipeline.get_by_name("capture_sink") pad = queue.get_static_pad("sink"); pad.add_probe(Gst.PadProbeType.BUFFER | Gst.PadProbeType.BLOCK, pad_data_probe_preroll_capture, self) self._pipeline.set_state(Gst.State.PLAYING) if self._pipeline.get_state(Gst.CLOCK_TIME_NONE) == Gst.StateChangeReturn.FAILURE: raise CameraError("pipeline cannot be prerolled") It seems to work, but multifilesink captures some old frames instead of new one (player is at 10s but captures saves frames from the 1st seconds) </pre><pre style="background-color:rgb(255,255,255);color:rgb(0,0,0);font-family:"courier new"">Any suggestions, I've tried to play with the queue parameters but without any success. </pre><pre style="background-color:rgb(255,255,255);color:rgb(0,0,0);font-family:"courier new"">Is it the preferred way to capture screen on events ? As events are quite frequent (but not time based) disconnect the capture branch seemed overkill. </pre><pre style="background-color:rgb(255,255,255);color:rgb(0,0,0);font-family:"courier new"">Also note that, multifilesink will be replaced by appsink once it is working. </pre><pre style="background-color:rgb(255,255,255);color:rgb(0,0,0);font-family:"courier new"">Thanks, gzp </pre></div>