[Libav-user] multi-thread decoding

[YIRAN LI]

Hi guys,

I'm researching the impact multi-thread decoding may have on memory usage.
Does anyone know if enabling multi thread decoding will use more memory ?
(so that more threads used, more memory required?)

I tried to decode an H.264 encoded 4K video using command:  ffmpeg.exe -v
error -i a.mp4  -threads 0 -f null - 2>error.log
>From Win10 resource monitor, I can see decoding with -threads 0 launches 11
threads, -threads 1 launches 6 threads and -threads 2 launches 8 threads
while memory consumption are at same level.

I'm testing on a 4-core i5 cpu. Below are the screen shots when running in
-thread 0, -thread 2 and -thread 1. Seems in all 3 cases there're only 6
valid threads.
Can anyone tell me what the other threads are doing?

Thanks


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