Stuttering in Playback Window

Luke2v52Luke2v52 Website User Posts: 5

I am working on editing some gameplay recorded with Nvidia's Geforce Experience. I am aware that the recordings are in VFR.

My Laptop Specs:

CPU: Intel 7th Gen Core i7-7700HQ

GPU: Nvidia's Geforce GTX 1060

Video RAM: 6GB GDDR5

System RAM: 16GB DDR4-2400MHz

I am trying to add the auto color, auto contrast, and auto level effects, but when I add them, it causes my video to stutter during playback. I have tried it with the original VFR footage and with another version made in handbrake using the Norman AVC method with 60 FPS. I tried to apply the effects to the transcoded version, but it did not seem to have any effect compared to the original. they both still stutter. I was wondering if the video just needed time to load the effect in properly due to the file being nearly 100 GB and 5 hours long. Any help would be appreciated.

Comments

  • NormanPCNNormanPCN Website User Posts: 3,945 Enthusiast

    The auto effects (color, contrast, levels) are much slower than using normal effects to do the same thing.

    60fps is a demanding standard. Your CPU is probably not fast enough for AVC video in Hitfilm.

    You probably need to transcode to Cineform for better edit performance. Your source media will increase from 3-5x in size from Nvidia AVC screen capture.

  • Luke2v52Luke2v52 Website User Posts: 5

    What do you mean by the auto effects being slower?

    I have worked with 60 fps before with no issues with both the raw footage and transcoded versions. It only stutters when I used those effects. So is there is a way to check if my CPU is okay to work with AVC? 

    How would I transcode to cineform using ffmpeg or handbrake? I have both, so whatever you think is best. Lastly, that file size increasing might be a bit of an issue for me since the file is 100 GB. I would like to trim it, so it multiplies a smaller number. Should I trim it in hitfilm, export that file, and then transcode, or is there another method you would recommend?

  • NormanPCNNormanPCN Website User Posts: 3,945 Enthusiast

    "What do you mean by the auto effects being slower?"

    Pretty self explanatory. They take longer to execute than normal effect that do a similar function. For example auto contrast is slower than Brightness&Contrast. A normal correction/grading effect simply performs the effect based on your settings. The auto function must do a full analysis, on every frame, to then compute the settings that will perform the actual effect.

    Then of course auto does what it thinks is reasonable. This might be different than what you want.

    "I have worked with 60 fps before with no issues with both the raw footage and transcoded versions. It only stutters when I used those effects."

    As I said, the auto effects are slower than the normal effects that perform similar functions.

    "How would I transcode to cineform using ffmpeg or handbrake?"

    You would not use Handbrake or ffmpeg to transcode to Cineform. You would likely use VirtualDub.

  • Luke2v52Luke2v52 Website User Posts: 5
    edited December 2018

    What would be your recommended settings for VirtualDub?

    Do you think using the normal effects instead of auto would remove the stuttering?

    Edit: Sorry if I am not fully understanding. I have limited knowledge about editing in general as hitfilm is my first editing software. 

  • NormanPCNNormanPCN Website User Posts: 3,945 Enthusiast
    edited December 2018

    If the auto effect causes playback to skip/stutter it (timeline playback) will never smoothen out. It will stutter for the duration of whatever effects are causing playback to stutter/skip (not real time). This assuming that playback is real time without the effect(s). Only RAM preview  can get you real time playback for a timeline that cannot make realtime playback speed (for whatever reason(s), e.g. effects, compositing, etc).

    Consider this argument. Let us say that it takes the brightness&contrast effect 1 second to do its work on a single frame. Then let us say that it takes auto contrast 2 seconds to do its work on a single frame. Then by those numbers the best playback speed you can get with brightness&contrast is 1 frame per second. With auto contrast best you could get is 1/2 (0.5) frames per second. Auto contrast is slower. The real speed of the effects is obviously much faster than the numeric examples I posed here.

    I believe the three auto effects are some of the effects that execute on both the GPU and CPU. This (CPU use) causes performance overhead (slowdown) of effects in Hitfilm.

    If auto causes timeline stutter then there is nothing you can do to stop the stutter other than to not use the auto effect. Changing the media with a transcode will not help. That only helps for when one gets playback stutter without any effects at all.

    Common Cineform recommended transcode settings are 10-bit 4:2:2 and Medium compression setting.

    https://fxhome.com/forum/discussion/42015/how-to-use-virtualdub-filtermod-to-fix-vfr-issues-and-convert-to-cineform#latest

  • Luke2v52Luke2v52 Website User Posts: 5
    edited December 2018

    I tried using the normal effects like you said, and it removes the stutter completely, so if I can't make the auto work, I will just look into how to color correct. 

    I am curious about what you said about playback stutter versus timeline stutter. It seems that timeline stutter means I can't fix the stutter, but if the issue is playback stutter, then I can change my preview to a RAM preview and that might make it play better (unless I am completely misunderstanding). If I am understanding properly, then how do I change my preview to RAM.

    edit: Nevermind I figured it out. Thank you for all the help!

  • CleverTaglineCleverTagline Moderator Las Vegas, NVModerator, Website User, Ambassador, HitFilm Beta Tester Posts: 3,038 Ambassador

    Glad that you got it figured out! Now to bring up a different issue: file size.  Even though things appear to be working well now, I strongly suggest chopping down your video into smaller bits. Asking any editing package to work with a 100GB, 5-hour file is incredibly demanding. Even a one-hour file is a bit much. Try breaking it up into 15-minute segments, give or take.  You can probably find pieces that you know you won't use in your final edit, and use those as the break points between files.

  • NormanPCNNormanPCN Website User Posts: 3,945 Enthusiast

    I created an ffmpeg file splitter script that works on typical MP4/AVC files. It's default is to split into 10 minute segments with the files named in numeric succession. e.g. MyFile_00, MyFile_01, MyFile_xx

    The script is in the ZIP in my AVC transcode thread.

    https://fxhome.com/forum/discussion/42415/transcoding-to-fast-decode-avc-for-timeline-edit-performance

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