HitFilm keeps Crashing on longer clips

cmddata Posts: 12 Just Starting Out*

I'm trying to edit footage in composite shots that are around 1h15/30m long, at 1080p60 with playback at 1/4 resolution but changing the position of the clip on the timeline is agonizingly slow, and when I tried to jump frame by frame the app completely died on me. This has been happening fairly regularly and it's pretty annoying.

My specs:

i5-11440F, 32GB RAM, MSI 6600XT


  • Stargazer54
    Stargazer54 Posts: 3,891 Ambassador
    edited October 2021

    I expect that the slowness is due to calculating the entire clip every time you make a change. Would be best to split up the original clip into smaller chunks. That said, why edit in a comp? That is pretty much kamikaze anyway since comps are for compositing effects on shorter clips.

    Might be best to use the editor to cut down the original, render that out and then re-import to add effects. Again very long clips in either case are problematic.

  • cmddata
    cmddata Posts: 12 Just Starting Out*

    Well I need to crop my original clip to 960x1080, any better way to do that than with comps?

  • Triem23
    Triem23 Posts: 20,280 Power User

    @cmddata In general Hitfilm (and, really, any NLE) will perform better with shorter clips (admittedly Hitfilm slows down more with super long clips than, say, Vegas Pro). I usually recommend splitting long clips to 10-15 minute segments.

    There's a few boring techie reasons for this, mostly due to caching and backend stuff, but we'll stick with caching - if you load in like a 90 minute file Hitfilm has to cache the whole thing before you can edit. Splitting into shorter files means you'll be able to start editing the early segments while Hitfilm is caching later segments. That's less time waiting.

    Splitting segments would be done with a third party transcoder. Handbrake is an excellent, free choice for mp4 transcode. It can also transcode VFR to CFR if you have variable frame rate footage to correct.

    Handbrake can also change resolution of clips and can re-crop them, so Handbrake is your stop to conform timing (cuz you were also mixing 60p/30p footage if I remember correctly), fix VFR and crop your source footage.

    Plenty of tutorials on YouTube.

    I forget - did I link to you my "Optimize Footage" tutorial? That contains some encoder settings for Handbrake developed and tested by @NormanPCN which gives good edit performance in Hitfilm with high retention of detail and reasonable file size.

    About 23:40 in this video. Faster to just relink than type the prior paragraph.

  • NormanPCN
    NormanPCN Posts: 4,371 Expert
    edited October 2021

    For simple file splitting I provided an ffmpeg command file to do the splitting. ffmpeg is free, but it is command line only so no simple UI to the do steps. The good thing here is that I have the split not re-encode video. It just splits into pieces, leaving the original file as is.

    For those curious, the command is something like this. Splits into 10 minute segments. Any codec.



    ffmpeg -i %1 -map 0 -c copy -f segment -segment_time 600 -reset_timestamps 1 "%~dpn1_%%02d.mp4"

    if errorlevel 1 goto error


    if NOT %1$==$ goto top

    goto :EOF


    echo !!! error encoding !!!


    REM The segment time is in seconds.

    REM 60 = 1 minute

    REM 600 = 10 minutes



    You can use VirtualDub to split a file without re-encoding. Any codec. Not a simple one step process but not tedious.


    There exists an inexpensive Windows tool to simple splitting. It says it is capable of splitting with re-encoding. However I have not tested it as the trial download does not support the "fast" encodeless mode. The free trial only support the re-encode mode. You have to purchase a license for encodeless mode.

    the tool is named Bandicut. 29.95 USD.


  • Triem23
    Triem23 Posts: 20,280 Power User

    @NormanPCN I don't normally use FFMpeg (even Handbrake I just normally use for transcoding phone vids of my cats), but I'm certainly gonna copy out that command line you listed above. Thanks for sharing!

    And, because super slo-mo and cats are a good combo, here's Ghost doing a couple of six foot jumps to kill the red dot at 1/10th speed.

  • NormanPCN
    NormanPCN Posts: 4,371 Expert
    edited October 2021

    I edited my post with a the full command script. It is just setup to loop over many files dragged/dropped on the command script icon.

    My fast decode AVC thread has the link to my fast decode AVC scripts ZIP file. I need to update the google drive file with the zip that support MOV as well as MP4.


    Always love cat vids.

  • TheBenNorris
    TheBenNorris Posts: 2,042 Staff

    @cmddata Please contact support with as much information as possible, hopefully they can identify the issue www.fxhome.com/ask