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Best way to benchmark 32 vs 64 bit transcodes

Posted: Sun Feb 15, 2015 10:28 pm
by joshag
I just picked up some new hardware and I'd like to run some benchmarks on my old system and compare it to my new one.

I'm running Windows 7 64 bit.

I'd like to compare 32 bit vs 64 bit performance on both systems.

The new server has quite a bit more RAM then my older one. Any performance tweaks for ffmpeg I might be missing? (64 GB) It's also quad processor, quad core.

What's the best way to get accurate results? Command line? Or use a pre-existing benchmark app?

Appreciate the replies.

Re: Best way to benchmark 32 vs 64 bit transcodes

Posted: Tue Feb 17, 2015 8:32 pm
by llogan
Simply time each command.

Use the same inputs, commands, and ffmpeg versions (I'm referring to the same commit hashes, not the same exact binaries).

You can compare decoding with:

Code: Select all

ffmpeg -i input -f null -
(Windows users may have to use NULL instead of -, but I'm not sure about that).

Decoding and encoding with:

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ffmpeg -i input -c:v <your desired video encoder>  -c:a <your desired audio encoder> -f null -
Decoding, encoding, and muxing to an actual file with:

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ffmpeg -i input -c:v <your desired video encoder>  -c:a <your desired audio encoder> output
The "-benchmark" global option may be of interest to you.

Re: Best way to benchmark 32 vs 64 bit transcodes

Posted: Wed Feb 18, 2015 5:01 pm
by qyot27
llogan wrote:You can compare decoding with:

Code: Select all

ffmpeg -i input -f null -
(Windows users may have to use NULL instead of -, but I'm not sure about that).
No need to use NULL on Windows, - will work fine. I was running benchmarks yesterday or the day before to find total number of frames FFmpeg could detect in a file, and that was the easiest way to do it.

Re: Best way to benchmark 32 vs 64 bit transcodes

Posted: Thu Feb 19, 2015 8:39 pm
by llogan
Good to know, thanks.