1080P 60 Video Lag!

fxhomer173436 Posts: 45 Just Starting Out*


So I have been trying to edit videos now and its all very laggy, choppy etc, At first I thought to change some settings and so I did, but nothing made a difference.

So then I re-installed Hitfilm and that made no difference..

Lastly I read that someone said that "Hitfilm is very GPU heavy" So I did a little test pulling up task manager and going to performance tab, only to see that when I playback the video my CPU went straight to 100%.

Paused it's around 25%-35% so I assume for what ever reason, Hitfilm is using a lot of my CPU and I'm wondering if there is any way to reduce it...

Theres Probably Tutorials that Hitfilm has done on Youtube to fix this issue but I'm not 100% on that.

Thank you in advance! :)


  • spyresca
    spyresca Posts: 288 Enthusiast
    edited August 2021

    Make sure your footage is friendly towards editing (i.e. generally .264 constant frame rate--- See many other threads for the particulars). If not, trancode it and try working with it again.

    Also, no one will be able to help you here until you provide specification of your computer and your footage.

  • Triem23
    Triem23 Posts: 20,397 Power User

    As spyresca says, first thing we need to know are your system specs - CPU, GPU, OS, RAM and Storage.

    If you're seeing "100%" GPU utilization playing back a single video stream and "25% GPU" when idle, chances are you have a low spec, integrated GPU, probably at about bare minimum spec. Maybe even a tad below. We won't know until you post your specs.

    We'll also need to know more about the video file. You'll want to download "MediaInfo" (it's free), generate a "Tree" report for the file and paste it here.

    Other than optimizing input video for playback there's not much you can do. Your hardware will ultimately determine your level of performance.

  • fxhomer173436
    fxhomer173436 Posts: 45 Just Starting Out*

    My PC Specs:

    RAM: 16GB

    Processor: i7-7700K CPU, 4.20GHz

    System Type: 64 Bit

    As for the video side of things, I have done that and I hope there isn't anything personal in there... Like privite info such as where I live, my phone number etc..

    I doubt it would be in there but better to be safe than sorry I guess..


    Is there anything else you guys would need?

    I record with OBS as well for those who are wondering..

  • Triem23
    Triem23 Posts: 20,397 Power User

    Ok, so...

    Your system, as predicted, is on the low end for Hitfilm. The Intel HD 630 integrated into your CPU is about 50% faster than the minimum spec Intel HD 5000 (for comparison, my Nvidia 2060 is about 2800% faster than the HD 5000 and, by 2021 standards, the 2060 is a low-mid range GPU).

    Unfortunately the "HD" 630 - while technically capable of running a 4k monitor - has a video decoder designed for HD (1080p) footage. It's the UHD line that's designed for 4k.

    If you look at MediaInfo report you posted you'll see.

    Frame rate mode             : Constant

    Frame rate                : 60.000 FPS

    The bold "Constant" was what we were looking for. If it said "Variable," then that would be a problem.

    However, you said you were recording with OBS and OBS has a glitch when recording 60fps footage where it sometimes actually records a variable frame rate (VFR) alternating 59fps and 61fps. Video cameras and broadcast actually use a frame rate of 59.94fps. Since MediaInfo is reporting a "true 60," let's assume we have VFR footage.

    Ok, so no NLE likes VFR footage. NLEs want constant frame rates (CFR). VFR footage can cause all kinds of problems and should always be transcoded to CFR before import to Hitfilm...

    So... Take a look at this video starting at 23:40. There is a section on converting VFR to CFR using Handbrake (free). There are also tested settings to produce a file optimized for editing. (the later parts of the video show other software for transcoding, earlier parts discuss how digital video works, with a longer explanation of why VFR is a problem).

    Note - all cell phones and tablets shoot VFR video. If you ever use phone footage you'll need to transcode.

    Transcoding is about the only thing you can do to improve playback speed.

    NLEs don't like long clips. Since this is OBS footage I'll assume it's from a game. While you're transcoding for VFR/CFR, I would recommend splitting your source footage into segments no longer than 10-15 minutes. I had two root canals today and don't feel like typing up that part of the explanation, but there are four different reasons why splitting your footage into smaller segments will make Hitfilm faster and more stable. Take this as a note for your next project, because, later in this post I'll tell you how to preserve the Edit on your current project after transcoding. If you split the footage on your current project, you'll have to re-edit

    Your footage isn't quite "4k," which would be 3840x2160. Your footage is actually 3440x1440 - which is a little unusual. Still, make sure your project size is 3440x1400. If you're accidentally editing 3440x1440 footage in a 3840x2160 Timeline you'll 1) have "black bars" on export around your video and 2) be wasting system resources on Hitfilm "thinking about" empty space.

    The only other things you can really do to speed up playback are to open Windows Task Manager and close out anything running you don't need, don't run other programs along Hitfilm, and use the Viewer controls in Hitfilm to drop viewer resolution to 1/2 or 1/4 and trade detail for speed. Again, you have a near-minimum-spec GPU, and, in general, the GPU is the most important component in a computer for speed of editing. The transcode should make a noticeable difference. The recommended settings in the linked video were developed by a "Professional Computer Nerd," who spent a month transcoding then editing until he found settings that preserved high quality images and edited quickly in Hitfilm.

    Ok, so, you've transcoded your footage for your current project. How do we use it, but preserve your current edit? Easy! Right click your footage in the Media Bin, select "Relink" and choose the transcoded file. Done! Now, I didn't go into detail above, but VFR footage can cause frame drift, so just go through your edit and make sure nothing drifted a frame or two. If something shifted, grab the "slip" tool from the Edit tools left of the Timeline. This slips the frames used inside the in/out points of the clip on the Timeline, so that will nudge everything back into place, quickly.

    Think that covers everything. If anything is unclear, ask again. If anything is unclear, I'll blame the codeine. 😉

  • fxhomer173436
    fxhomer173436 Posts: 45 Just Starting Out*

    So firstly, That is a heck of a lot to read and 95% I don't understand. I get Handbrake is free and that I should use it to I guess "Convert File Types".. No idea what "NLE" means.. But, If this is the ONLY way to speed up playback then I got no choice. Hitfilm does work with the footage of yes a game, Just not smooth framerate. I haven't really edited much so if I have to re-edit it, it's not that big of a deal. BTW, Most things I just won't understand cause of my low IQ but that's a different topic. Back to the topic at hand, I will try Handbrake, and I'm not 100% sure why splitting up a 1hr long video into multiple 10-15 minute videos to edit is a good Idea because I'd personally rather have to edit 1 file and not really multiple. Also I don't know how to split it up into multiple little files unless I export each section 1 at a time from hitfilm then re-import it into hitfilm but not have the multi-audio track option available which kind of defeats the main part of the editing.. Unless If I use Handbrake, I can still edit with multi-track audio?? I have already done everything else like Task manager etc and that hasn't done anything so Handbrake really is my final and only option.. Also maybe about a couple of version ago (Or something like that) My PC seemed to have been running fine and had all the system requirements met. So I'm not really sure why it's "Low-End" now...

    And you are right, My videos arn't "4k" They are indeed 1080P, I used to try have 4k footage but then a friend explained and showed me that having that really isn't necessary so I stopped since then. Just wanted the best quality for my viewers..

  • fxhomer173436
    fxhomer173436 Posts: 45 Just Starting Out*

    Just tried to load it into hitfilm and found 2 problems instantly..

    1. Found that its not a multi-track audio so I can't edit it how I would like to...
    2. There is absolutely 0 Audio playing, No waveforms, nothing.
    3. It does playback a LOT smoother but there is no point until we can get the first 2 problems sorted...
  • Triem23
    Triem23 Posts: 20,397 Power User

    Oh, let me break down the prior post a little bit more, then we'll talk about your new audio issues. Sorry, again, it's a lot of reading, but... It's a complex topic, and you're getting a full crash course here.

    NLE= Non Linear Editor. Hitfilm, Premiere, Avid, Resolve, etc... Pretty much any video editor on a computer is an "NLE." Linear editing is the primitive days when we were literally slicing and taping frames of film to a reel or editing footage directly onto a videotape.

    HD = High Definition. This is any footage above the old SD (Standard Definition) standard of roughly 640x480. "HD" footage, TECHNICALLY is 1280x720. "Full_HD" footage is 1920x1080. UHD is "Ultra High Definition," and technically refers to 3840x2160 footage, although "UHD" is also used to refer to true 4k 4096x2160 resolutions and anything higher. There's a 2550x1440 resolution which, I guess, is "HD?" It's a little tricky because "HD," "Full HD" and "UHD" have specific resolution meanings, but the terms are used imprecisely.

    Point being the GPU you have is in the "HD" line and was designed to work with HD and Full_HD resolutions. UHD is higher, and some Intel processors do have "UHD" GPUs.

    CPU and GPU mean "Central Processing Unit" and "Graphics Processing Unit." In short, the CPU is a computer's brain. Around 2005 or so manufacturers started using a GPU as a "second brain" dedicated only to decoding video, drawing graphics frames and similar tasks, leaving the CPU free to do everything else.

    The GPU is, almost always, the most important link in a computer for determining Hitfilm speed. The GPU is what calculates all the effects and renders the video frames to screen.

    Why is VFR bad? A NLE needs and expects a steady "clock." If the project is set to 60 frames per second, then the NLE is thinking in frames of 1/60th of a second. In the case of VFR footage - in the case of OBS the big where it records alternating 59fps and 61fps seconds - the NLE is trying to fit in changing numbers of frames. 59 doesn't fit cleanly into 60 and 61 doesn't fit cleanly into 60. This means Hitfilm is - in real time - having to figure out where to duplicate a frame from the "59 fps" frames and throw away a frame from the "61 fps" frames to keep an even 60. This slows Hitfilm down and can cause other issues. In some extreme cases I've seen footage that was supposed to be "30 fps" that varied between 32fps and 0.5fps! When you hand Hitfilm something that's 32 frames that has to fit into 30 or something that's a half-frame that has to fit into 30 you can see that's a lot of extra thinking for Hitfilm at is tries to figure out what has to be thrown away or what has to be duplicated. VFR footage can cause all kinds of other problems besides slower performance.

    So by using other software, like Handbrake, to convert the VFR into a CFR of the proper frame rate, Handbrake only thinks about it ONCE and writes a new file so Hitfilm doesn't have the think about it at all. It just has a noce constant frame rate to use.

    Why is splitting up long video files good? There are a whole slew of reasons and I'll try to not get too techie here. Video files are BIG. There are few things we do with computers that use more data per second that video editing, and most of that is the hardcore science stuff. Video files are also highly compressed. Your original video file is encoded at a data speed of about 50mb/s or megabits per second. 50,000,000 bits per second, or so. However, the UNCOMPRESSED data rate of your footage - 3440x1400 at 60 fps - is about 7,133,184,000 bits per second. The true data in your video is 143 TIMES how much space it takes up on your drive. Those numbers will be as techie as I get, and all you really have to remember from this is that the file on disc is a lot smaller than what Hitfilm is actually working with.

    Hitfilm has to decompress the video frames before they can be edited. When a video file is loaded into a project Hitfilm has to create a "Cache" file, which is used to store some audio data and some other data, but it also has to try to hold frames in memory. You have 16GB of memory (we'll ignore that much of that is used by Windows and Hitfilm and other programs). Your original video file is 2GB. 2GB is 1/8th of 16GB so you'd think Hitfilm has all kinds of memory to play with, but, since the video is compressed by a factor of about 143 the 2GB file is holding. almost 286GB of actual data. 286GB is WAY more than 16GB, so, with the large files Hitfilm is having to use another cache file to store uncompressed data. This slows things down. Smaller files reduce the need to use cache files to store frame and help speed up editing.

    Additionally, remember how I said Hitfilm writes cache files when first loading a file? If you have a 2 hour video in a single file you'll just have to sit there and wait while Hitfilm takes a long time to write the initial chache files. If you've split the file into 10-15 minute segments, then your first segments are ready for editing while the later segments are still caching. You'll have less time sitting in front of your PC waiting to edit and more time editing. It still takes Hitfilm the same amount of total time to write the cache files, but, by doing it in several smaller segments it "feels faster" to you because you'll be able to edit the beginning of your footage while waiting for the end to cache instead of just waiting for the whole thing.

    Also, NLEs were, in general, designed to work with smaller scenes. TV shows and films very rarely have hour or two-hour single clips (except for things like award ceremonies recorded in real-time, but there, most of the editing was done live on a switchers).

    In short, it's easier for the computer and the software to deal with a several sort clips than one large one. You'll have fewer crashes working with 15 minute files than 2 hour files.

    Incidentally, it was literally impossible for computers to work with files larger than 4GB until about 2009/2010 or so. Older cameras or video capture apps used to have to split files at 4GB, no matter what. In most cases that worked out to auto-splitting a file every 10-15 minutes!

    HOW TO SPLIT UP YOUR FILES I'll link to this video here. Basically, you can use Handbrake by defining the first clip you want to split, adding that to the encode queue, then reloading the same video, defining the second segment, adding that to the queue, reload, enter the next time code, add to queue, then, finally, export the entire queue with all the video segment. Yes, I know that takes additional time to set up, but, you'll need to convert to avoid VFR issues, so you may as well take the time to split the files into short segments as well and avoid long file issues.

    Side note - there's a position on most TV shows/films, the "assistant editor." That job is actually taking all the files from all the cameras used on a show, logging them all (writing down what they are, the scene, the take, the camera, the shoot day, etc), as well as converting anything that might be VFR and splitting long clips into short clips. Yes, everything we're talking about here of making certain all footage is CFR and not super-long clips is so important to filmmaking that there's actually a specialist position for someone to do that job.

    Multiple Audio Tracks and Handbrake Sorry, I didn't pay attention to the multiple audio tracks in your original video.

    Multiple audio tracks cause a whole new set of issues in Hitfilm. First we'll discuss Handbrake.

    In Handbrake, when you're loading your original file for transcode there is an "Audio" tab in the same section where we discussed the video resolution and frame rate settings. Here you can select the different audio tracks to use in the transcode.

    Unfortunately, I don't ever work with video that have multiple audio tracks, so, best I can do is point you to this video.

    Multiple audio tracks and Hitfilm

    Here's where things get annoying again. You can load in a video with multiple audio tracks in Hitfilm, BUT, Hitfilm can only read ONE audio track at a time. This leaves you with two options.

    1. You can open up the video file in Hitfilm, right click the media file in the Media Bin and Duplicate it twice. Then right click each copy of the media file in the Media Bin, select "Properties," and select which audio track each instance is "using," then right click each copy again in the media bin and rename them to something like "Video - Audio track 1," "Video - Audio track 2," and "Video - Audio track 3." Then you'd drag one video to the timeline (it should fill a video and audio track), then hold ALT as you drag the second video file to Audio Track 2. Holding ALT means only the Audio will appear. Repeat for three. Yes, this means you'll have three audio tracks.
    2. You can use yet another third party program like Audacity (free) or VLC (free) to extract the additional audio tracks from your video and load them into Hitfilm as seperate audio clips to drag to different audio tracks.

    Either way, yeah, you have to edit three audio tracks. You can up vote this feature request thread.