Audio out of sync

Hi there!
I'm making a film for school but when I render it, the audio is 10(!) seconds out of sync at the end.
Is there a simple solution?
Maybe I found the answer myself: do the sample rate AND the bitrate have to be the same as the project properties?
Sorry for my bad English, hope you understand my question :)
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Comments

  • Before I forget: the duration of my video is 20 minutes.
    Don't know if it is usefull :P
  • Make sure the video framerate and audio sample rate in the project settings match the footage as the first step.
  • Thank you so much for the quick reply!
    So the audio bitrate has nothing to do with it?
    Sorry for my silly question. It's my first time you know.
  • Probably not. Pretty much all video is going to be in 16-bit, and changing the bitrate isn't something you can do in HitFilm, you'd need a dedicated audio editing program for that, I think.
    The question isn't silly at all, so no worries there. There is lots of potential for confusion in the realm of audio and video format details, and asking questions is an important part of the learning process. Please, feel free to ask questions any time you like.
  • edited April 2012
    VBR encoding can cause sync issues. Convert the audio to PCM and try it. I would assume that HF up/down samples any audio to match the project setting, so when you do that with VBR it can go off.
    VBR = Variable Bit Rate
    PCM = .WAV
    Mustard and onion on a hot dog = Yum
  • I've tried everything but it is still 5 sec out of sync?
    The first 5 minutes are good but then it is starting to go wrong.
    Got an idea?
  • edited April 2012
    That can happen with ripped DVD's.:) Ahem...cough...cough....
  • Does your video have a pulldown pattern? If you're not sure, what frame rate is the video and what camera did you use to record it? (Even better, upload a small clip of the video from your camera so that we can take a look here.)
  • edited April 2012
    Hendo, I know what you're thinking. The telecine causes the audio to accumulate a longer and longer delay as the frames are shorted.
    Yeah, maybe apply Inverse TeleCine, or "Pull Up" to the video, or run the whole thing through a remuxer that can build a new index, like TsMuxer or AviDemux.
    And is the video interlaced? If so, you can de-interlace it at the same time you remux.
    Is the video Mpeg2? With AC-3 audio? If so, you can re-process it through AutoGK to come out as an AVI(Xvid/Mp3) and it will re-process the audio at the same time.
    All utilities mentioned are FREE!
  • Sorry I can't follow you :P
    What is a pulldown?
    I've recorded with a Zoom Q3-HD and a frame rate of 29.97, but I also included some footage from the internet such as photo's and a couple short movies.
    I can't figure out what is wrong. In my comp I included AVIs, WMV, MP3, JPG, PNg and one WAV.
  • edited April 2012
    So you're trying to render a mixed bag against one audio file?
    Hmmm...I don't know what the staff will say, but if it was me I would render the video with NO AUDIO first, then bring the render back into HF and see if the audio lines up.
    Then render again WITH the audio, and maybe you can narrow down the problem. I think you can unlink the audio, then after you render, delete the video and bring in the new rendered one.
    Pulldown is not likely an issue. Pulldown is found mostly on DVD video. Your video, and YouTube video is 30p.
    Now I'm suspecting the WMV.
  • What frame rate is your video? E.G 24FPS/29.97FPS What sample rate are you using on your audio? E.G 48KHZ/44.1KHZ
  • Your audio will drift apart if your shooting at 29.97fps - and your audio sample rate is 44.1khz
    Basically , make sure your audio sample rate is 48khz
  • edited April 2012

    Probably not. Pretty much all video is going to be in 16-bit,

    I'm sure you meant audio :) Pretty much all video passed around is 8-bit. :)
    I'm gonna have to bail off this thread because I don't know if HF resamples whatever audio that comes in as 48K, which is the default project setting.
    The sample rate of audio refers to the highest frequency(dynamic range) that's recorded, and the bitrate(bit depth) refers to the resolution of that sample.
    Neither have anything to do with the playback speed. Same as video resolution and bitrate have nothing to do with playback speed. 16/24 bit and 44,48,96K sample rate all play at the same speed.
  • edited April 2012
    Sorry, I was referring to the audio embedded into video files. So you are correct, I was referring to the audio, but specifically to the audio within video files. As opposed to audio-only files from sources other than a camera, which could use all sorts of different formats and bit depths and stuff. I should have been more clear.
    If you open up 16-bit audio in a 24-bit project, it will play back much faster than it is meant to, in the same fashion as opening 24 fps footage in a 30 fps project. When working in video editing, it would be extremely rare for that to come up, but I've done it in recording music before. I high;y doubt that it is related to the issue here.
  • edited April 2012
    When working in video editing, it would be extremely rare for that to come up, but I've done it in recording music before.

    Well, now I'm puzzled. Never experienced that. Probably because my DAW takes care of that silently?
    I mix disparate audio all the time. So my software must resample everything coming in. That's what I was wondering about HF.
    Yeah, of course fps in video are going to change the playback speed, unless the software automatically conforms the media, and that would involve removing frames or blending.
    Doesn't HF "conform" the audio by default? Isn't 48K just there as a default because that's probably good enough for 99.9999999% of the time?
    That's what I was assuming, but I may have made an ass/ out of /u/ and /me.:) ass/u/me, it's an old fart joke. I'm an old fart with an 18 year old's brain. Hahahaha....
  • @budwzr No, I have multiple videos with audio. The videos work great but when I put them together it is starting to go wrong.
    @Daniel Shooting at 29.97 FPS and a sample rate of 48 kHz

  • @budwzr No, I have multiple videos with audio. The videos work great but when I put them together it is starting to go wrong.

    Hey man, I'm clueless at this point.
  • Maybe I'll try to get al the bitrates at 32-bit, maybe it will help
  • Hhhmmm, doesn't seem to work :(
  • This is the same problem I am having posted in a different place (no replies yet so I'll delete it). The audio get's a bit ahead of the video. Audio is all 44kHz so am I stuck? Daniel Morgan, how could I cenvert the files from 44 to 48 and would this solve my drift of a couple seconds by the end of a ten minut film?
  • I found my problem... No video. During the editing process I added a fade to black. But instead of adding in balck video, I just left blank space in the timeline. Obviously, HF had no idea what to render there so it took a guess. I know this isn't a bug, but it may be something to address in an update so it either warns or fills it with signal.
  • Good! I'm sure they would like to hear about this.
  • Update... Not the problem. Crap! I have tried different playback software (VLC, Quicktime, Media PLayer), rendering at different qualities etc.
    I've removed effects, possible corrupted clips, taken out the soundtrack, almost anything I can think of. Well over 20 hours of changes and rendering a 10 minute movie...
    NOTHING works. I am so dismayed right now I could just toss my CPU!
    I am so wishing I had edited this in Vegas and ONLY used HitFilm for the effects (ala the old days). All I have is a film I had to show for my GRADE that sucked audio wise and no help no these forums. Hopefully I will magically discover what is wrong. Or someone that has an idea will read the forums.
  • That sounds frustrating, but don't take it out on your computer.
    Did you submit this issue to support, so one of the experts could work through this with you one-on-one?
  • edited April 2012

    Update... Not the problem. Crap!
    I am so wishing I had edited this in Vegas and ONLY used HitFilm for the effects...

    That's what I do. Vegas is rock solid. You should get in the habit of demuxing your audio, and consider that as a separate file.
    HF is good for FX, not as a general NLE. Maybe one day that will change, but it takes a long time to polish an app, and HF is definitely good as a side program for now.
  • opened a ticket. Crossing my fingers. Strange thing is the audio is fine in the timeline.
  • I believe I am having this same problem. The audio drifts out of sync from the video and it does it very quickly. The audio is from the camera and not an external recorder. Also, when the video is played in Windows Media Player, it works just fine. I only have the sync issue in HitFilm.

    HitFilm shows the folling attributes on the file in the preview window:
    1440 x 1080 pixels
    00;02;34;16 @ 29.97fps, Stereo @ 48000Hz

    The Media Properties show the audio as:
    Format: 19-bit Stereo Sample Rate: 48000 Hz
    Codec: MPEG Layer 2

    Am I using the wrong settings on my camera perhaps?
  • edited May 2012
    You should have received a support ticket reply, but unfortunately it's something we need to look into in more details -
    Would you be able to upload a sample of your clip, just so we can test it here in the Office?
    Could you upload it to here: http://upload.fxhome.com/ (50MB Limit)
    Once we have the file we can run some tests that will hopefully solve the issue for you.
    Do let us know (by replying to the support ticket) when it is there, and what the file is called.
    We will try and get it sorted as soon as we can
  • Yes, I can do that. I will pull out a chunk of the clip and upload as soon as I can.
    Thank you for your time and the response! :)
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