[Libav-user] Threading a h264 video decoder - timing is odd.

[Karel Vorechovsky]

"threaded video reader to spread the decode workload on some more cores 
and gain some speed"

Decoding of the same stream must happen within one codec context. If you 
want speedup, read and buffer packets in one thread and do decoding in 
another. If that's not enough, look for faster decoder.

Karel


Dne 3.6.2016 v 14:09 Jesper Taxbøl napsal(a):
> Hi Guys,
>
> I am working on a threaded video reader to spread the decode workload 
> on some more cores and gain some speed. My source is included below:
>
> The thing is that I dont see a time improvement when starting two 
> processes instead of one. On a 80mb mp4 file it takes 6 seconds to 
> decode the video, while doing two in parallel takes 12 seconds. I can 
> see that two cores's are used 100 percent. Im on a fast SSD disk so I 
> dont think im IO limited.
>
> What could be the case. Is it the same decoder taht is doing all the 
> work? Do I perhaps need to instantiate a context or something?
>
> kind regards
>
> -- 
> Jesper Taxbøl
>
> _______________________________________________
> Libav-user mailing list
> Libav-user at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/libav-user