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<p class="MsoNormal">I’m working on an application that renders video streamed via WebRTC, and I am a little puzzled by the amount of CPU and GPU that this uses. The pipeline is basically as follows:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">webrtcbin ! queue ! glimagesink<br>
<br>
While streaming an HD video source, my application (on Windows) is using appr. 10% CPU and 25% GPU. If I view the exact same WebRTC stream in the Chrome browser, it uses appr 4% CPU and 0% GPU.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I know the absolute number given here mean nothing, but I am struck by the fact that Chrome can render this using half the CPU and without using the GPU at all.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am fairly certain that the resources are consumed in glimagesink and not the other elements of the pipeline, because if I replace glimagesink with fakesink, then my application’s resource consumption essentially goes to zero. Also, if
I insert a caps filter before the sink to reduce the resolution, this also reduces total resource usage, despite being an additional processing step.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’ve also tried replacing glimagesink with d3dvideosink. Both use roughly the same resources.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Given that Chrome is likely highly optimized for this particular use case where Gstreamer is a much more general framework, I would not necessarily expect performance parity in this case, but does anyone have any suggestions for possibly
reducing resource usage while maintaining video quality and resolution in this scenario? I’m also struggling to understand why glimagesink and d3dvideosink would be using the GPU at all (much less so heavily) when Chrome seems to do entirely without.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">/ Thorsten<o:p></o:p></p>
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