A lag between recording audio & video

jashothi
jashothi Website User Posts: 3 Just Starting Out*
edited August 17 in HitFilm

Hi there,

I'm new to HitFilm and loving the software. I have recorded video using my Windows native 'Camera App' software, and then imported into HitFilm.

I'm using a Lenovo Yoga laptop. When I filmed on Camera App, there's a very slight lag when I play the video back.

When I import to HitFilm, the lag is slightly more noticeable... I'm wondering if this is down to HitFilm, or the laptop I am using?

Has anyone else encountered this? Is there a way I can stop this happening?

Update: I've also noticed the lag seems to be different in different portions of the final video... [the final file consists of 24 videos edited/merged together)

Thanks in advance :)

Jas

Best Answer

  • triforcefx
    triforcefx United StatesModerator, Website User Posts: 1,269 Moderator
    Accepted Answer

    @jashothi

    Welcome to the forums! I’m glad you’re enjoying HitFilm so far!

    Unfortunately, pretty much all laptop built-in webcams are garbage. Even in the most expensive laptops they can be low quality, low framerate, steaming piles of trash. This is your first cause of “lag”. Your phone’s cameras are probably better. Consider using your phone for future videos if possible.

    The second issue is something called Variable Frame Rate (VFR). Note that this will affect your phone too, so keep on reading even if you decide to switch to a phone or tablet to record. Phones, tablets, and laptop webcams record in VFR, while more “professional” cameras record in Constant Frame Rate (CFR). Video editors (including HitFilm) don’t count in milliseconds, they count in frames. Because of this, they prefer a Constant (exact same over time) Frame Rate, rather than a Variable (always changing) one. VFR requires extra processing for HitFilm, and it tends to bring the audio and video out of sync.

    The fix for this is Transcoding (converting) your video to CFR. This video from Film Sensei shows you one of the easiest ways to get up and running with that:

    If you want a more in-depth explanation of all this, check out this video from HitFilm University (Triem23):


Answers

  • Triem23
    Triem23 Moderator Moderator, Website User, Ambassador, Imerge Beta Tester, HitFilm Beta Tester Posts: 19,928 Ambassador

    To build on what @triforcefx writes - your phone camera is probably better quality than the built-in Webcam, but 1) your phone will also be VFR, so you'll need to transcode, 2) instead of the built in Windows webcam software, you can use something like OBS instead. By default OBS records VFR, but it can be set to record Constant Frame Rate (CFR) so you won't have to transcode.

  • jashothi
    jashothi Website User Posts: 3 Just Starting Out*

    Wow, thank you both, this is all really helpful.

    Gosh, looks like I'll need to start recording differently... off of my laptop, for starters. I might give my iPhone SE a whirl.

    Alternatively, do either of you know a reasonable priced ($150 or less) simple, portable video camera? I really just want decent quality recording, with point-n-press recording. For me, the simpler the better!

    Thanks again.

  • triforcefx
    triforcefx United StatesModerator, Website User Posts: 1,269 Moderator

    @jashothi

    Are you using the older iPhone SE (looks like iPhone 5S) or the newer 2020 SE (looks like iPhone 8)?

    Both cameras on either phone will be far better than any laptop webcam.

    The rear cameras on both phones will be better than any camera at or under $150 (unless you can find an amazing deal on a used dslr/mirrorless camera).

    If you want to use the front camera, you will lose some quality, but it can be worth it to have a viewfinder if you’re filming yourself. The old SE is just ok and only films in 720p, but the newer SE films in 1080p and is actually pretty decent. Both front cameras are still probably better than a sub-$150 camera, especially in the audio department.

  • jashothi
    jashothi Website User Posts: 3 Just Starting Out*

    hey @triforcefx, I'm on the smaller one (same size as 5s).

    My front camera is real blurry, but the rear one works just fine, so given my budget I might try to find a tripod for it and go from there. I think it'll be good enough - thanks for the reassurance :)

  • triforcefx
    triforcefx United StatesModerator, Website User Posts: 1,269 Moderator

    Interesting. I used to have a 5S and I don’t remember the front camera being particularly “blurry” per se. If there’s a screen protector over or near it, that could be affecting the camera (even if it’s a clear-looking glass one). Also be sure to clean the area (with rubbing alcohol if needed), as it’s easy for the cameras to get covered in fingerprints and other gunk.