Issue with decklinksrc - Precaution for any live src element

Baby Octopus jagadishkamathk at
Wed Jul 3 10:26:53 PDT 2013


I'm using decklinksrc element to capture video from an SDI camera and
streaming it over the network after encoding

*gst-launch-1.0 decklinksrc mode=10 name=src src.! video/x-raw ! tee ! queue
! h264enc ! mpegtsmux name=mux ! udpsink host= port=5050 src.!
audio/x-raw ! tee ! queue ! audioresample ! lamemp3enc ! mux.*

Here are the issues that I saw, which is probably not taken care in
decklinksrc though its a live src

1. The pipeline hangs whenever h264enc fails to run realtime(for above
720p). How should a source skip frames if the encoder can't run realtime?
2. When I add videoscale and feed 360p to h264enc, I see ocassionally a
particular frame still having part of older frame. This older frame is
always 60frames behind the current frame. I see src writing into the buffer
when h264enc is reading it. I see some buffer lock missing or release not
happening properly

As I see, this is a trivial issue a live src can encoder. Can somebody throw
some light on how to *skip frames* and *release buffer properly*

I have reproduced these issues consistently. I would like to file bug. If
somebody can throw some light, I would like to fix and give patch


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