Cpu usage

System specs:

Cpu: R5 1600

Ram: 16gb standard speed

Gpu: Geforce gtx 670


Im just wondering, when im exporting videos my cpu usage is only at ~50% and shouldnt it be at 100%? Just wondering this because it would go faster if it got as much power as possible.

Thanks for answers :)


  • Triem23Triem23 Moderator


    Here's how Hitfilm works:

    • GPU is idle. CPU reads source frames from video and decompresses frame. 
    • CPU passes data to GPU. CPU goes idle. 
    • GPU generates VFX filters and compositing then renders final frane. 
    • GPU passes back frame to CPU. GPU goes idle. 
    • CPU compresses frame and writes to file.
    • Repeat.

    There are a few more things that may happen (CPU would calculate particle physics, for example), but this is close enough. In short, rarely (if ever?) will the CPU or GPU ever peg up to 100%. 

  • Hitfilm is unable to fully load the CPU or GPU in most circumstances during export due to how it's pipeline operates. Some encoders are single threaded as well.

    Sadly is appears Cineform export/encode is single threaded from a quick look in version 8.

  • Does this mean that Hitfilm is less efficient than other programs? Would encoding in Hitfilm with the same hardware and settings be slower than in Vegas Pro, for example?

  • edited May 17

     "Does this mean that Hitfilm is less efficient than other programs?"

    Pretty much yes. Depends on what your compare against and doing exactly what. Blanket statement without specifics are not terribly useful. For example, on specifics, Vegas on Nvidia and Vegas on AMD GPUs is quite different. Vegas OpenCL code has sucked on Nvidia. Don't know if that has been fixed in 15.

    "Would encoding in Hitfilm with the same hardware and settings be slower than in Vegas Pro, for example?"

    Again a non specific scenario, but I would say most likely compared to Vegas Pro.

    In a quick specific example. I take a 1080p30 Cineform High file and put it on a 1080p30 timeline. I render/export to Cineform High. Hitfilm is very poor here. It only manages 15% utilization. (4C/8T machine so 12.5% is one thread fully loaded). There are certainly multiple threads running but there is a bottleneck somewhere and I know of at least one of the bottlenecks.

    Vegas 14 does about twice as a fast as Hitfilm at export and utilization roughly reflects this.

    Resolve however, pegs my machine to the wall and is by far the fastest of the three. It is not even close. Maybe 6-7x faster than Hitfilm.

    There is no real GPU here as this specific test has no effects. Putting some curves and wheels in does not change the result.

    You should not directly care about utilization, but more about absolute speed. The two however are closely related. That said, a crap algorithm can peg the CPU to the wall and be slower than something with less utilization. Absolute speed is what counts.

    Now encoding to AVC in MP4 will get different results which will be different from PNG or EXR export and so on.

    All this is about export/render. How much do you do that? I don't know about you but I spend forever working on something. Export is the least of my worries.

    Hitfilm has a ton going for it when it comes to using the software and the features/functions it offers. Excluding the NLE (IMO). The NLE is functional but often annoying and tedious but there is that ok so nice integration with the composite timeline.

  • Triem23Triem23 Moderator

    One should also note that exports can be very different depending on what's being done. In many ways Hitfilm can be slower than, say, Vegas, because Hitfilm has a more (potentially) complex flow of operations. Vegas certainly doesn't do a lot of the advanced things Hitfilm can do, so one would have to compared by using 2D effects only on the editor timeline with no Composite Shots. Composite Shots are tricky--is the comp proxied? In that case it's just a video file. If not, then it's a procedural media that has to be calculated for each frame. If it's an embedded comp then it's rendered before the main comp is rendered. If you have an embedded comp in a main comp and the main comp is on the editor timeline and neither comp is proxies then the deepest nested comp is rendered, then the main comp, THEN the Editor timeline can render out... So, to compare in Vegas we need to create a Vegas projected, nest that in a second project, then nest THAT into a third project... No one edits in Vegas with nesting like that.

    But, yes, if one were to drop a couple of media files in the editor, add a few basic color correction effects and a crossfade transition in both programs now we're comparing apples to apples and we can asses relative speeds of the software (in this instance). Vegas probably renders to file faster.

    So now we get to a larger question of workflow. I happen to have Vegas Pro AND Hitfilm. I obviously love both programs (hell, I've been on vegas since version 1!). With that said, Vegas Pro is a superior editor to Hitfilm. That auto-crossfade of overlapping clips is a smarter workflow and faster workflow than any other NLE, period! Vegas has vastly superior audio tools (Still probably the best around although I've not poked around in Fairlight--Resolve--yet). So Vegas is my prime editor. Hitfilm is the program I use to build all that advanced animation stuff (and 3D) that Vegas can't do at all (we're not counting Vegas's limited 3D--it's there, but one has a single, fixed focus "lens" camera that remains static and one has to move the universe around it... No lights. No DoF...).

    This could also apply to Resolve--edit in Resolve (and color correct, since resolve has the best CC tools), but use Hitfilm for the things that are easier to do in Hitfilm than Fusion (i.e. almost everything, unless nodes really make sense to you). Nothing wrong with using and moving between multiple programs. The "big boys" do that all the time! A film might take elements from Houdini, MASSIVE and Maya all composited in After Effects for one shot before being sent off to Premiere or Avid to be edited into the film then shipped off to Resolve for coloring while ProTools does the final audio mix...

    At the level most Hitfilm users are at, yes, we'd like to do everything in a single program--and Hitfilm is one of the better choices for this--but don't get married to that idea. With Hitfilm, Resolve, Krita/Gimp and Audacity any person has access to two powerful, free editor/compositors, two powerful, free image editors, and a powerful, free audio editor. That's a crapload of power for no money! Add in Blender and that's full 3D modeling and animation! Free! Blender can even export models and animation data to load into Hitfilm. Drop in Autodesk Matchmover, and that's a free point-tracking 3D camera solver that can export data to Hitfilm! As far as I can tell that basically covers pretty much every aspect of film-making. Free! So use the best program for the task and don't be afraid to move files between programs!

    Sorry, I wandered off-topic. I'll get off my soapbox.

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