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Export to Quicktime – Video & Audio Synch issues – The final word
Hi there folks
I have had issues with quicktime audio synch issues for years and googling around it seems lots of other people do, and even on this site there are various attempts to solve the issue. so i thought i would try and get to the bottom of it since i have 100 students who want answers on this topic too.——-
our workflow is this:
we create all our animation one frame at a time either by drawing, rendering from 3ds or after effects as tiff still sequences.these go into premiere cs5 currently, as sequences (sometimes as a single still for a held scene)
normally we will render preview files to work in real time
viewing in the premiere cs5 work environment everything plays back perfectly in synch
we render out by going into the encoder and choosing either animation uncompressed quicktime, avids codec, or h264 quicktime depending on whether it is a final submission or just work in progress
viewing these files in vlc or windows media player results in audio and video playing back perfectly in synch
viewing in quicktime results in the video being 6 frames late
now it was only recently that we discovered this was not entirely a render out from premiere issue, but rather more likely a quicktime issue
so there are several parts to the answer which i seek:
which is truly in synch, premiere and vlc, or quicktime? and how do i get it so that everything is in synch?
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4 Replies
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To clarify, are you experiencing this sync mis-match with every codec? In particular, this issue strongly occurs with h.264 when it’s wrapped in an MPEG container (mp4) rather than a Quicktime container and played back with Quicktime.
– Angelo Lorenzo
– https://FilmsFor.Us Helping you sell your film online -
yes the out of synch issue is present with which ever codec i am using.
i used to render out as uncompressed avi, then i switched to quicktime compressed with animation
i render straight out from premiere as h264 (mp4 extension) too and had come to forget about the synching issue because this is set to open in windows media player by default, but as a recent client of mine pointed out, the audio was out of synch on their machine and i had to get them to install a different player to view it.
so yes. what i am looking for is a bullet proof once and for all solution.
1. confirmation that if it is synched in premiere, then it should render in synch irrespective of the format or compressor
2. confirmation that rendering as quicktime uncompressed(animation), h264 mp4, and finally as DnxHD from premiere will produce in synch files
3. why quicktime is consistently out of synch on what ever machine plays it
4. any export tips which will ensure that my files are in synch irrespective of the player, in particular quicktime since most people i deal with tend to default to this as their player
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I’m going to skip question number 1. and 2. Since I’ve worked with all three codecs and used them in some combination in Premiere, Avid, Virtual Dub (uncompressed AVI) and FCP without sync issues that can be viewed in a NLE timeline. This looks purely related to playback and I’ve also warned a number of clients about it in certain situations (relating to my MP4 example in my earlier post).
With that being said, some research says that +/- a full frame late is normal on digital systems because of frame buffers and the refresh rate of your monitor (since your NLE can’t sync lock your monitor to your footage)
I did a render test of a 640×480, 29.97fps file with a test tone for two frames exactly at the 30 second mark in a number of formats. Premiere did fine bringing back in the footage, as did After Effects and Virtual Dub (AVI and MPEG). Quicktime was consistently 6 frames early on audio sync for playback.
I also went back and reviewed some h.264 MOV files from my 5DmkII that were slated with a smart slate, and again I could read a 6 frame difference from the slate timecode and the actual clap; the audio was early in this instance too. This was to confirm the issue on a file that Premiere never processed directly.
Oddly, you can search on Google and 4-6 frames drift seems to be the sweet spot, with a full 15 frames (half second) reported in some cases. I’ve also looked up forum threads all the way back to 2003 with the same issue.
I would say it’s just time to educate your clients on using VLC or other alternatives. It’s like doing design work and your clients complaining about a color when their screen isn’t calibrated… there are just going to be discrepancies when using less that professional level tools.
– Angelo Lorenzo
– https://FilmsFor.Us Sell your film and connect with your audience -
thanks for the thorough response. Apple and their shitty negligence to professional work flow is the bain of my life.
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