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Transcoding performance

Added by A T over 5 years ago

Hi,

my Wifi is not good so i tried to transcode to save bandwidth.
Currently im running HTS Tvheadend 4.1-2346 on Odroid XU4

Not sure if my hardware is capable but using ffmpeg:
ffmpeg -i HD.mkv -c:v libx264 -preset ultrafast -crf 28 -c:a copy -y out.mkv
HD.mkv is a recording from a Hd-channel and i get around 80-90fps.

When setting x264 ultrafast in the transcoding settings my video is stuttering even on sd channels and hd are like 3-4fps at best.

What makes me wonder is that my cpu usage is only 200/800% (8 core system) so maybe its not transcoding on all cores?

Is there something i can try or another way to save some bandwith?


Replies (3)

RE: Transcoding performance - Added by Poul-Henning Hemberg over 5 years ago

Could you post a little more about you hardware/software. Processor ram Linux os etc. With 8 cores (all working)I don't think that there will be a performance issue.

RE: Transcoding performance - Added by A T over 5 years ago

http://www.hardkernel.com/main/products/prdt_info.php?g_code=G143452239825

  • Samsung Exynos5422 Cortex™-A15 2Ghz and Cortex™-A7 Octa core CPUs
  • Mali-T628 MP6
  • 2Gbyte LPDDR3 RAM PoP stacked

OS is Debian Jessie.

From what i found its still not enough power.
I did myself a favor and changed to a J4205. Roughly same power consumption but more power and better software support.
Even Vaapi-Hardware encoding is working for live transcoding. (with "okay" quality and only h264, h265 produces black errors)

RE: Transcoding performance - Added by Poul-Henning Hemberg over 5 years ago

I'm absolutely no expert on the subject. I know for a fact that transcoding on a raspberry pi is very unlikely to work (tried it my self). That said this setup looks a lot more powerful. But if you have some kind of desktop installed you could try looking at system monitor (as the screen dump). This would indicate if OS/TVH Transcoding uses all cores.

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