Accelerated scaling on OMX RPi

Jan Schmidt thaytan at noraisin.net
Fri Apr 10 05:24:22 PDT 2015


Hi,
On 09/04/15 14:48, raphord wrote:
> I've been searching for some time but can't figure this one out... I
> have 8 threads running on a single Linux box generating 8 UDP streams
> being multicast on 8 different "channels". This much is working fine but
> in order to keep the CPU workload I am using frame sizes of 960x540 @ 30
> frames per second. I have a raspberry pi (not the absolute latest
> gstreamer code but from about 2 months ago compiled on the pi) showing
> this stream using the following pipeline: gst-launch-1.0 udpsrc
> multicast-group=226.1.1.6 auto-multicast=true port=7001
> caps='application/x-rtp,encoding-name=H264' ! rtph264depay ! h264parse !
> omxh264dec ! glimagesink This stream works fine and shows the video fine
> with about 25% CPU utilization. The screen resolution of the pi is set
> to 1920x1080 and I want to scale the image up to fill the screen. I can
> make it the right size using videoscale but I'm assuming this doesn't
> use the hardware because the CPU hits the maximum and complains of the
> computer being too slow. What do I need to put into the pipeline to
> double the size of the video in hardware? Alternatively I don't mind
> hacking the code to double the size if I can be directed where to put
> this.... I don't need a general solution as the scaling will always be 2
> times larger.

You can use glcolorscale as a substitute for videoscale which will do 
the scaling using the GPU, however you're better if you write a small 
python script or so to embed the glimagesink window into a window you 
create yourself and just make the window fullscreen - it will directly 
scale the output to fit the window, and avoid the extra texture copy you 
get from using glcolorscale.

- Jan.

> ------------------------------------------------------------------------
> View this message in context: Accelerated scaling on OMX RPi
> <http://gstreamer-devel.966125.n4.nabble.com/Accelerated-scaling-on-OMX-RPi-tp4671513.html>
> Sent from the GStreamer-devel mailing list archive
> <http://gstreamer-devel.966125.n4.nabble.com/> at Nabble.com.
>
>
> _______________________________________________
> gstreamer-devel mailing list
> gstreamer-devel at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel
>


More information about the gstreamer-devel mailing list