<html><head></head><body><div>Le lundi 27 février 2017 à 07:05 -0800, Adam Plocher a écrit :</div><blockquote type="cite"><div dir="ltr">Nicolas, thank you for your response. fdsrc seems like it would be a good solution, but I'm having issues getting it to work.<div><br></div><div>It seems like I need to specify the caps after the fdsrc, otherwise it fails in other ways. e.g.</div><div><br></div><div><br></div><div>Specifying text/x-raw:</div><div><br></div><div>tail -f /home/pi/test.txt | /opt/gst/bin/gst-launch-1.0 fdsrc fd=0 ! "text/x-raw" ! txt. videotestsrc ! videoconvert ! decodebin ! textoverlay name=txt ! omxh264enc target-bitrate=800000 control-rate=3 ! tcpserversink host=0.0.0.0 port=9000<br></div></div></blockquote><div><br></div><div>I think you forgot to keep subparse element.</div><div><br></div><blockquote type="cite"><div dir="ltr"><div><br></div><div>Results in:</div><div><br></div><div><div>Pipeline is PREROLLING ...</div><div>ERROR: from element /GstPipeline:pipeline0/GstCapsFilter:capsfilter0: Filter caps do not completely specify the output format</div><div>Additional debug info:</div><div>gstcapsfilter.c(455): gst_capsfilter_prepare_buf (): /GstPipeline:pipeline0/GstCapsFilter:capsfilter0:</div><div>Output caps are unfixed: text/x-raw, format=(string){ pango-markup, utf8 }</div><div>ERROR: pipeline doesn't want to preroll.</div></div><div><br></div><div><br></div><div>Specifying text/plain:</div><div><br></div><div>tail -f /home/pi/test.txt | /opt/gst/bin/gst-launch-1.0 fdsrc fd=0 ! "text/plain" ! txt. videotestsrc ! videoconvert ! decodebin ! textoverlay name=txt ! omxh264enc target-bitrate=800000 control-rate=3 ! tcpserversink host=0.0.0.0 port=9000<br></div><div><br></div><div>Results in:</div><div><br></div><div><div>0:00:00.501757360 4549 0x1e085c0 ERROR GST_PIPELINE grammar.y:714:gst_parse_perform_link: could not link fdsrc0 to txt, txt can't handle caps text/plain</div><div>WARNING: erroneous pipeline: could not link fdsrc0 to txt, txt can't handle caps text/plain</div></div><div><br></div><div><br></div><div>No caps at all:</div><div><br></div><div>tail -f /home/pi/test.txt | /opt/gst/bin/gst-launch-1.0 fdsrc fd=0 ! txt. videotestsrc ! videoconvert ! decodebin ! textoverlay name=txt ! omxh264enc target-bitrate=800000 control-rate=3 ! tcpserversink host=0.0.0.0 port=9000<br></div><div><br></div><div>Results in:</div><div><br></div><div><div>Pipeline is PREROLLING ...</div><div>WARNING: from element /GstPipeline:pipeline0/GstTextOverlay:txt: Could not multiplex stream.</div><div>Additional debug info:</div><div>gstbasetextoverlay.c(2449): gst_base_text_overlay_video_event (): /GstPipeline:pipeline0/GstTextOverlay:txt:</div><div>received non-TIME newsegment event on video input</div><div>WARNING: from element /GstPipeline:pipeline0/GstDecodeBin:decodebin0: Delayed linking failed.</div><div>Additional debug info:</div><div>./grammar.y(510): gst_parse_no_more_pads (): /GstPipeline:pipeline0/GstDecodeBin:decodebin0:</div><div>failed delayed linking some pad of GstDecodeBin named decodebin0 to some pad of GstTextOverlay named txt</div><div>ERROR: from element /GstPipeline:pipeline0/GstVideoTestSrc:videotestsrc0: Internal data stream error.</div><div>Additional debug info:</div><div>gstbasesrc.c(2951): gst_base_src_loop (): /GstPipeline:pipeline0/GstVideoTestSrc:videotestsrc0:</div><div>streaming stopped, reason not-linked (-1)</div><div>ERROR: pipeline doesn't want to preroll.</div></div><div><br></div><div><br></div><div>There is some information here (regarding the older version of gst-launch): </div><div><a href="http://gstreamer-devel.966125.n4.nabble.com/Dynamic-text-again-td3676141.html">http://gstreamer-devel.966125.n4.nabble.com/Dynamic-text-again-td3676141.html</a><br></div><div><br></div><div>And that links to this bug that was resolved (again, old gst-launch): </div><div><a href="https://bugzilla.gnome.org/show_bug.cgi?id=654959">https://bugzilla.gnome.org/show_bug.cgi?id=654959</a><br></div><div><br></div><div><br></div><div>I've seen a couple examples which used the "text/plain" caps.</div><div><br></div><div>I'm certainly open to cracking open the Python lib and giving it a shot. I would need to read up on it a bit and I'm not familiar with the appsrc, either, but that's something else I'm open to. I have done very basic stuff with the Python libs but nothing too fancy or dynamic (basic pipelines, no more complex than I would get from gst-launch-1.0).</div><div><br></div><div>What would you recommend? Is there an example or resource you could point me towards?</div><div><br></div><div>Thank you for your help</div><div><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Sun, Feb 26, 2017 at 2:46 PM, Nicolas Dufresne <span dir="ltr"><<a href="mailto:nicolas@ndufresne.ca" target="_blank">nicolas@ndufresne.ca</a>></span> wrote:<br><blockquote type="cite"><span class="">Le dimanche 26 février 2017 à 06:18 -0800, Adam Plocher a écrit :<br> > Hello, I apologize if I'm posting this in the wrong place. I've<br> > previously asked this on stackoverflow and never got a response: http<br> > ://<a href="http://stackoverflow.com/questions/42128804/polling-a-text-file-and-" rel="noreferrer" target="_blank">stackoverflow.com/<wbr>questions/42128804/polling-a-<wbr>text-file-and-</a><br> > overlaying-the-result-in-<wbr>gstreamer<br> ><br> > I have a Raspberry Pi with a camera and I'm live streaming that back<br> > to another unit (it's for a baby monitor). On the same Pi, I have a<br> > temperature sensor that is dumping the current temp to a file every 5<br> > seconds.<br> ><br> > My question: Is it possible to somehow poll that txt file and update<br> > a text-overlay on the live stream based on the current contents of<br> > that file?<br> <br> </span>filsesrc does not have this feature unfortunatly. I believe using<br> fdsrc, you could:<br> <br> tail -f text.txt | gst-launch-1.0 fdsrc ! ...<br> <br> Let me know if that is a good work-around. If you are writing an app,<br> this can be done with a pipe, or if you prefer, with appsrc.<br> <span class=""><br> ><br> > I've tried using a filesrc and subparse, and it will grab it<br> > initially if I format the input text file properly, but it doesn't<br> > seem to update itself:<br> ><br> > gst-launch-1.0 -v \<br> > filesrc location=/home/pi/temp.txt ! subparse ! txt. rpicamsrc<br> > awb-mode=0 awb-gain-red=1 awb-gain-blue=2 rotation=0 bitrate=820000<br> > preview=false brightness=67 contrast=30 sharpness=40 \<br> > ! video/x-h264,width=800,height=<wbr>480,framerate=10/1 \<br> > ! h264parse ! decodebin ! videoconvert ! clockoverlay shaded-<br> > background=true draw-shadow=true font-desc="Nimbus Mono" \<br> > ! textoverlay name=txt shaded-background=yes \<br> > ! omxh264enc control-rate=3 target-bitrate=850000 \<br> > ! tcpserversink host=0.0.0.0 port=5555 sync=true<br> ><br> > The input file looks like this:<br> > 1<br> > 00:00:00,000 --> 99:59:59,000<br> > 69 degrees<br> > Thank you!<br> </span>> ______________________________<wbr>_________________<br> > gstreamer-devel mailing list<br> > <a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.<wbr>freedesktop.org</a><br> > <a href="https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" rel="noreferrer" target="_blank">https://lists.freedesktop.org/<wbr>mailman/listinfo/gstreamer-<wbr>devel</a><br>______________________________<wbr>_________________<br> gstreamer-devel mailing list<br> <a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.<wbr>freedesktop.org</a><br> <a href="https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" rel="noreferrer" target="_blank">https://lists.freedesktop.org/<wbr>mailman/listinfo/gstreamer-<wbr>devel</a><br> <br></blockquote></div><br></div> <pre>_______________________________________________ gstreamer-devel mailing list <a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.freedesktop.org</a> <a href="https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel">https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a> </pre></blockquote></body></html>