How to use multicore?

I’m newly working with shotcut; unfortunatly, I just found out, that Shotcut is using just one thread… So, it takes forever to render a video.

It does not matter which format/codec/etc i use - it’s always just one thread used…

Using an i7 with 4 cores/8 threads, I could spare some cores… Is there an option that needs to be activated?

Shotcut 17.02.05
running on Linux Mint 18.1
Core i7 4970
16GB ram

Pls. let me know if you need further infos…
Thanks for your help!

Features page states:

Multi-core parallel image processing (when not using GPU and frame-dropping is disabled)

Is ‘Parallel Processing’ checked on the export panel?
All six cores on my machine are used.

Hi Steve,

Yes, Parallel Processing is activated… (GPU-Processing is disabled)

Edit: a few hours and another crash later, following observation:
when i’m using the DVD (dv_pal)-profile, it actually uses all 4 cores including hyperthreading, but never exceed 50% CPU-Usage (so it’s on “half speed only”, so to speak)

I’ll give it a try on Windows tomorrow, to check if it’s machine- or system-related… (except anybody knows where I made the mistake…?)

It is using multiple cores. It just cannot always all of them up to 100%. Heavier codecs such as x264, x265, and vp9 will use more than the others.
The feature Steve mentioned: “Multi-core parallel image processing (when not using GPU and frame-dropping is disabled)” is for when previewing, and the “Parallel Processing” option in Export does the same thing. But, again, due to bottlenecks and deficiency, it cannot always use all CPUs 100%.

Hi Dan

Thanks for the explanation…

Trying the H.264 High Profile, it actually uses all threads up to 90%.
I’ll check the codecs, as most mpeg-codecs only have the mentioned “1 thread to 100%”-behaviour…

(still have to find my ways through the codecs - I’m still (again) new to the editing-topics :slight_smile: