Blackmagic Forum

I tried to sync the two tracks... it is NOT working in 17.4.2 build 9 on M1 - App Store install.

The waveform is very simple, and I can do it manually. But not auto.

Looking at the pic I would say that the waveforms are too dis-similar for a match to be made. You can see the effect of the mp3s compression. Also that mp3 is possibly not the same speed either as you can see that the waveform is progressively going more and more out of sync, so even if you sync the front manually it will still not be in sync by the end. Using a wav file would be a much better option.

Also, though I don't know if things are different with a Mac, but according to Nvidia the GTX 680MX only has a Compute Capability of 3.0 and Resolve from version 16.2.8 requires an Nvidia GPU to have a minimum Compute Capability of 3.5.

the MP3 should not 48khz and may also variable bitrate

transcode it to a 48khz WAV file with constant bitrate

@charles
it is a M1 mac, no nvidia or amd involved

Only going by what's in his signature where it says GTX 680MX.

ok, now i have seen it

maybe he will clear it up and the apple store version
is a limited version anyway - i would never buy it

Mark Foster wrote:the MP3 should not 48khz and may also variable bitrate

transcode it to a 48khz WAV file with constant bitrate

hmm, a workaround... since it works in premiere pro, but I will give it a go

Mark Foster wrote:the MP3 should not 48khz and may also variable bitrate

transcode it to a 48khz WAV file with constant bitrate

@charles
it is a M1 mac, no nvidia or amd involved

it CAN work with MP3, 48000 Hz but I can't see if the file was constant or variable. But there is no need to transcode as you said. Since I can do it on my other files I have made.

Variable bitrate should not be a problem, but it seems that the speed is different.

As Charles says, the waveforms are too dis-similar. The mp3 looks extremely affected by automatic gain control. Sync manually and move on.

Gary Hango wrote:As Charles says, the waveforms are too dis-similar. The mp3 looks extremely affected by automatic gain control. Sync manually and move on.

no is NOT the problem (what I think is more the problem, is that, when not the hole file can be linked to the original file, so instead of e.g. take first 1-2 min. and just try to align them it take the full 60 min. and if somethings is missing it just say NO this is not the same!

It doesn't need to look at the whole track it needs just one main sync point such as the peak of a clapper board or handclap. If you are expecting the syncing function to retime your audio to make it fit that's not what it is for or can do.
As I said before the waveforms are too dissimilar with the mp3 missing all the peaks, and it is clearly not running at the same speed as you can see the drift.

I believe Plural Eyes can correct for drift. It's expensive though, so likely only an option if you'll be doing this regularly.

Yes, it can, with certain limits.
If you only need it for one project, IIRC they have a 10 days fully functional demo.

TheBloke wrote:I believe Plural Eyes can correct for drift. It's expensive though, so likely only an option if you'll be doing this regularly.

Plural eyes is ****... I have been there and it is the same... it is NOT listen to the track and I have gotten more mistakes on a bigger production! So dont talk it up!

On a bigger production you should use proper TC. Any kind of waveform syncing is for small indie endeavours. As Charles already explained in detail, your waveforms are too different. If Premiere can handle them, use Premiere.

Uli Plank wrote:On a bigger production you should use proper TC. Any kind of waveform syncing is for small indie endeavours. As Charles already explained in detail, your waveforms are too different. If Premiere can handle them, use Premiere.

I know! I use tentacle sync! But sometimes you forget or like here it is impossible. Still would be nice if it will have some options, maybe say "only listen to this part of the file". So could be better but sometimes it works.

Well, looking at your waveforms there is an obvious drift and maybe too much for PluralEyes too. As I wrote, it has its limits when compensating for drift, which DR can't do at all. Sometimes it has helped us in such cases.

So, if you have to sync by hand or try to use the automatic, you'll have to cut it into shorter pieces to shift. Then you can try to tell it to listen "only to this part" anyway.

Uli Plank wrote:Well, looking at your waveforms there is an obvious drift and maybe too much for PluralEyes too. As I wrote, it has its limits when compensating for drift, which DR can't do at all. Sometimes it has helped us in such cases.

So, if you have to sync by hand or try to use the automatic, you'll have to cut it into shorter pieces to shift. Then you can try to tell it to listen "only to this part" anyway.

This is a really BAD advice... if you cut a 60 min. file down without sync of the audio, that is just stupid, since you only need for it to line up ones!

I think there has been very good advice from the users here.
Your waveforms don't match. That is not a fault of Resolve.

Uli is not telling you to cut it down from 60mins. He's telling you to merely place cuts at intervals so that you can try the waveform syncing on smaller sections. Going by your screenshot the drift is likely to be so great that you won't be able to manually sync it either.
Post a screen shot of the entire timeline so we can see how much drift there is between the tracks by the end.

Thanks, Charles, that’s what I meant.

Peter Cave wrote:I think there has been very good advice from the users here.
Your waveforms don't match. That is not a fault of Resolve.

nothing wrong with the waveforms, when zooming in, there I can see it visually, that they match.

ADMIN - delete this post - since I dont think anyone here wants to have this function work better!

It's actually you who doesn't like it to be fixed.
If you seriously want that instead of just complaining, post two samples with which to reproduce the problem, not just screenshots.

Uli Plank wrote:It's actually you who doesn't like it to be fixed.
If you seriously want that instead of just complaining, post two samples with which to reproduce the problem, not just screenshots.

¨well no one from Blackmagic has asked for them...

You may get more attention from BM if others can confirm the issue.

Hmm, would be nice if anybody from BM would answer!

I just align two new projects... (same kind of files like the ones not working). This time with another tvserie ontop of the other track... I would think this it would find out... like last time... now it is working... so my question is this some kind of A.I. offline or online or just offline sync or it sends to a server and there is gets better and better...

am beginner, but appears that my similar problem fixed by moving audio clip to track right under video track.

Before, it was a few tracks below.

Anyway, that's the only thing I changed besides disabling "snap into place" magnet.