Extremely Sluggish Preview

Hi, so while working on Hitfilm 14 i'm noticing that no matter what i do, my preview gets extremely sluggish. For the record i'm using recordings from ShadowPlay (gaming videos) which were treated in Handbreak for turning em into Constant FPS videos and then transcoded from MP4 (h.264) in DNxHD to have a uncompressed file that could be used easily on Hitfilm... Problem is that i still get those issues of sluggish playback, especially when i start applying Chroma Key on some of the clips i have, in which case it drops frames all over the place even at 1/4 preview resolution.

For the record, nothing is running in the background and my hardware specs are:
- GTX 970 (4GB Vram)
- Ryzen 5 2600 3.5ghz
- 16 GB DDR4 Vengeance Ram (3000mhz)
- SSD 240 GB (Video files i'm working on are here)
- HDD 1.5 TB (Program is here)
- File format right now is: 1920x1080p DNxHD in .mov format


  • @RuggieroITA Your system seems to be in spec.  And you have rightly transcoded the gameplay footage to  constant frame rate. So you're doing all the right things.  I would guess that maybe the Ryzen 5 may not be keeping up once you add the key.  You might try transcoding to Cineform and see if that offers some improvement.

    Also, check your Playback Quality settings and kick that down to Draft.  Just be aware that if you go lower down to Fastest, then your effects will drop out in favor of prioritizing the footage playback.

  •  @Stargazer54 thanks, i'll give you an update as soon as i transcode again in Cineform format (i'm using Davinci Resolve to be specific) and re-link everything in Hitfilm. Alternatively i know there's also DNxHR but if i recall it seems that xHD is the preferred alternative so i don't know if it's even worth wasting time transcoding that one specifically

  • DNxHR and DNxHD are at their core the same codec. xHD was a restricted spec (frame size and rate combos) and xHR is unrestricted.

  • @NormanPCN given recent changes to Hitfilm I'm inclined to recommend transcoding to NormanAVC instead of DNxHD/R. 

    Since you figured out those settings, I figure you'd have an opinion, but Cineform/DNxHD/R seems such overkill for a Shadowplay grab I'm thinking NormanAVC and hardware decode is the way to go for this user. 

  • edited December 2019

    Ok so results from the Cineform test @Stargazer54: they work in 1/2 preview resolution combined with Playback quality set to quick and it Keeps solid even in the moment where there are 4 Chroma key effects applied to 4 different clips (again all stuff is 1080p), although it tends to get slightly choppy, it's leagues above what i had before, it's not a jump cut fest basically... however while i was ok with the filesize of DNxHD , which was slightly more than double the size of the original files, Cineform is outright too much. We go from 18GB of DNxHD files to 67GB of Cineform files, which i think it's a little overkill.

    Also thx @NormanPCN for the clarification with DNxHD/HR.

    As for @Triem23, i pretty much agree with you but again i don't mind sacrificing some space for better editing as long as we don't go the Cineform Size i guess lol As for the NormanAVC, i tried to look for a codec to download but i can't find anything about it so any link for that specific codec download would be appreciated as well as a suggestion of any other uncompressed/editing codec solutions to test out (since i'm new to Hitfilm i'm pretty much testing before dropping on bigger projects/work projects). I'm eager to learn as much as possible on this program cause i kinda like not having to jump between AE and Premier just for  a few clips (although i miss nested clips lol) Btw, one thing i forgot to mention is that i'm working on 60FPS videos ... so idk if that could be also an issue for the program (don't know, maybe it doesn't handle 60FPS well ? I know hitfilm is relatively young compared to even Davinci Resolve right now when it comes to some stuff, kinda like with Markers and Nesting)

  • @RuggieroITA "NormanAVC" is just a term coined on this forum for AVC/H.264 encode settings that have a lower decode overhead. A link to my thread is as follows.


    Since Hitfilm has Hardware decode for AVC these days it (AVC) is a good option for decode performance.


    DNx requires Quicktime for decode and as such typically will not perform as well has Cineform or Prores. Both of which are native to Hitfilm.


    You already discovered one advantage Cineform has with decode versus other codecs. Better decode performance at lower viewer resolutions. Viewer at half or quarter res.

  • @NormanPCN ok so my best bets, excluding Cineform (because good lord the size) are either Prores at this point or transcode a h.264 file in another h.264 file which is set specifically to be decoded better thanks to the recent Hardware rendering option i saw in a few Hitfilm pro 14 update videos 

    I'll try both but for the h.264 transcode with the settings: can i use Handbreak instead of Virtual Dub for it ? If so, what settings should i use in extra options ? I saw an old 2017 video that stated to use these settings:
    H.264/RF = 20 or 18 / Audio is 192kbps /Advanced options: keyint=10 bframes=0 (written exactly like this and this is the video: https://www.youtube.com/watch?v=Yqhl0mRuTng)
    If not what are the specific settings to use ?

  • edited December 2019

    "ok so my best bets, excluding Cineform (because good lord the size) are either Prores at this point or transcode a h.264 file"

    Cineform, Prores and DNx will be the same size. Equivalent relative settings. For example, Prores has LT, Standard and HQ and Cineform has Medium, High and Filmscan. These are roughly similar to each other. I often suggest one try Medium for Cineform for most source material. Your eyes are the only judge that matters here.

    If you don't want to transcode AVC to AVC, then find/use a screen recorder that does not generate variable framerate video.


    Handbrake is fine for transcoding to AVC.


    As for settings I would refer you to my thread, which I linked in my previous post. I have edited that and/or added posts to keep it enough up to date. I have listings and screenshots for Handbrake and VirtualDub and also supply ffmpeg scripts for those so inclined.

    I comment a little on what setting to use for the CRF bitrate mode of x264. That setting is somewhat subjective. I gave a couple of choices to start with.

  • So, i think i have my winner format: ProRes 422, which like you said, performed pretty much the same as Cineform. Now i just need to decide the filesize, but i think i'll stick to either Proxy or LT since i will be just doing "Editing/Cutting" with no color correction (it's a Music Video with gaming footage my current project but i don't need any fancy stuff except masking/keying) and then replace that footage with the h.264 footage i already had to finalize the project.

    Thank you for the help: @NormanPCN@Stargazer53 / @Triem23

    If you can answer me one final thing (unrleated to this) that i tried to get answered in another post but still didnt' get any answer:
    Basically in After Effect, when i "mask" an object i tend to add more masking point as time passes, so that i don't put too many unnecessary mask points and just use the necessary ones. When i do that, those new points adapt to my old keyframes so they pretty much follow the mask i was already making... now, i tried to do the same thing here and i saw that if i add a new mask point, pretty much that point doesn't try to get in line with the mask in my previous key frames and instead it remains stuck in the position i creaded it, it just adds on the other keyframes without however following the pattern of the mask, so i have to go back and place that point in any old key frame i made. Is there any setting to avoid that or it's just that Hitfilm right now is limited in that department ?

  • edited December 2019

    I would think ProRes Proxy or Cineform Low settings probably too low for an intermediate format. But as I said, "Your eyes are the only judge that matters here." 

    If you are concerned about file size then stick with AVC.

  • Hitfilm doesn't support a variable number of mask points in a mask. 

    So, if you create a mask on frame X with 24 points and, on frame Y add points 25 and 26, these points will appear on frame X... With the frame Y position data since that's the only existing data.

    So, yeah, exactly what you're seeing. Hopefully the devs will change the behavior in the future. 

  • edited December 2019

    @NormanPVC like i said above, i don't have any problem when it comes to extra file size as long as it's not too much (in fact LT is actually bearable compared to Cineform), however i wanna test all file variants of ProRes just for experience since i never worked with ProRes files. But yeah, i'll try to stick to AVC next time for simple projects

    @Triem23 thanks for the confirm, i was afraid that was the case. I guess i'll have to use a LOT more key frames to compensate or just cut during a composite shot everytime i want to add more points. It's too bad i can't make Nested shots in this case (don't know if can do something similiar here) cause they would come in handy.

  • "i don't have any problem when it comes to extra file size as long as it's not too much (in fact LT is actually bearable compared to Cineform)"

    You keep saying things like this that do not make sense. Cineform has extremely similar bitrate/size variants to Prores. I outlined this previously. It sounds like you are comparing the largest Cineform variant to smaller Prores variants. Anyway, choose what works for you and be happy.

This discussion has been closed.