Poor Optimization for Timeline Playback; crashing with DNxHD codec

ChessChallenger Website User Posts: 2 Just Starting Out*

Hey all, I've been trying to edit a video but the incredibly delayed and choppy playback window is making that nearly impossible for me. I searched online for solutions, including things like reducing playback quality and effects, but that didn't work. During this, I found out about video codecs.

I had been using the NVENC H.264 codec for recording; I record stuff through OBS. I wanted to record a game and my webcam in full definition to be able to cut between them while editing, so I set my OBS canvas size to 3840x1080 and recorded like that. Importing this file into Express is when the playback was simply far, far too choppy to edit properly with, though these problems have always happened.

While researching this, I found out that many people claim the DNxHD codec works very well in Hitfilm, so I looked for a way to transcode my file into that codec to solve this problem. MPEG Streamclip seems to be a commonly used program to transcode to DNxHD, but I couldn't get it to work; it always crashed. To be clear, I recorded a 6 second clip in 1920x1080 with my original codec to test, assuming things could go south with the real clip due to the length.

I found another thread talking about other options to transcode to DNxHD, but none of the options there worked. Video2Video didn't ever launch, and ClipToolz2 is no longer available, nor is 3. Seems there's a V6, but I don't know whether or not it works and there's no free trial.

I found two other programs that had free trials that converted to DNxHD codec in the .mov container, but importing that to Hitfilm caused a near instantaneous crash. I tried multiple times, and reinstalled Hitfilm, no dice. This was true of both files from these programs. Normal .mov files work just fine in Hitfilm, and changing those DNxHD encoded files back to .mp4 didn't help either. The only thing I could conclude is that 6 (or 3) second clips encoded in DNxHD caused immediate crashes in Hitfilm.

So... I'm now at a complete loss for what to do. DNxHD seems to be a dead end at the moment in terms of smoothing out timeline playback, but no other methods have made any headway either. Does anyone have suggestions? Something obvious I missed, hopefully?

Processor: Intel Core i7-4790 CPU @ 3.60GHz

Installed RAM: 16GB

Graphics Card: GeForce GTX 1060 6GB (newest drivers)

Windows 10, 64 bit


  • triforcefx
    triforcefx United StatesModerator, Website User Posts: 1,271 Moderator


    I’m guessing you’ve been looking at some very old threads, as DNxHD is pretty much never recommended for use in HitFilm these days- especially because, last I heard, it requires the outdated QuickTime on Windows which is considered a security risk.

    The main codecs recommended for use in HitFilm 2021 are AVC or Cineform.

    With hardware decoding, your system should handle most AVC files like a champ, so that is what you should use. You most likely have Variable Frame Rate video, which doesn't play nice in HitFilm or any other video editor.

    Even though this tutorial is a bit older, it shows you the easiest way to transcode your footage to Constant Frame Rate, which should fix the majority of your issues.

    If you want an in-depth look at video optimization, check out this video:

    @TheBenNorris While DNxHD is no longer a preferred format, it shouldn't be causing HitFilm to crash. Perhaps this has something to do with the change to OS codecs in Express?

  • Alk3mist
    Alk3mist Website User Posts: 6 Just Starting Out*

    I am having the same issue since updating to the latest version. And now I'm back up on videos to edit for you channel.

  • triforcefx
    triforcefx United StatesModerator, Website User Posts: 1,271 Moderator

    @Alk3mist Please see my previous response to this thread to fix your issue.

  • Alk3mist
    Alk3mist Website User Posts: 6 Just Starting Out*

    My issue is not with the Codec. I haven't made a single change to any of my settings since updating to the most recent release. I was good for a little bit and then all of a sudden, the most simple actions (changing font size) completely freezes the software for a few seconds at a time.