Qt5 Video playing takes 200% CPU

Technical Support
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1

Hello,
I’ve compiled a custom linux for Apalis-T30 based on the instructions of this page: High performance, low power Embedded Computing Systems | Toradex Developer Center.

I’m working with Qt-5.9, and QtQuick (qml) with X11.

All QML animations and effects works correctly, except videos. When playing a video, the CPU loads to 200%.

QtMultimedia plugin is linked with the gstreamer-0.10 libraries.

It seems that the DRI is not working. Can it be because the tegra3 graphics drivers?

With Apalis-TK1 and Apalis-IMX6 all works fine.

Bellow there is my image recipe attatched, and my xorg.conf:

xorg.conf
zokeypad-image.bb

2

hi @Oscar

Could you provide the version of the hardware and software of your module?

All QML animations and effects works correctly, except videos. When playing a video, the CPU loads to 200%.

Can you share the log of top -n 1 in a file? What display with which resolution and interface are using to display the video?

It seems that the DRI is not working. Can it be because the tegra3 graphics drivers?

Why do you think this? Did you check the GPU Usage?

With Apalis-TK1 and Apalis-IMX6 all works fine.

What is the CPU usage on these modules?

Thanks and best regards, Jaski

3

Hi @jaski.tx
Many thanks for your promt reply.

Model: Toradex Apalis T30 1GB V1.1B, Serial# 06373176

I think the DRI is not working, at least in the videos, because the CPU is >200%.

The CPU usage in the TK1 and IMX6 is about 25% - 40%

You’ll see in the screenshot that process “zokeypad” is playing the video with 219% of CPU usage in this case. It can vary from ~ 200% - 230%

Thanks !

alt text

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I forgote to reply: What display with which resolution and interface are using to display the video?

I’ve connected a monitor in the HDMI interface with a resolution of 1920x1080, but the video resolution is very low (960x540). mp4

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On T20/T30 one usually has to fine tune a particular gstreamer pipeline more or less by hand which is probably not what QtMultimedia does.

Do you know whether that particular file would play fine in our regular Angstrom LXDE demo image e.g. using nvgstplayer?

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Running gstream by hand with this command works fine:

gst-launch filesrc location=/home/video.mov ! qtdemux name=demux demux.video_00 ! nv_omx_h264dec ! nv_gl_eglimagesink demux.audio_00 ! nv_omx_aacdec

It seems that qtmultimedia uses playbin, how can I force qtmultimedia to use this command?

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hi @Oscar

I saw you wrote also on E-Mail Support. Is the issue now solved or not?
Best regards, Jaski