Go Back   Cockos Incorporated Forums > REAPER Forums > REAPER for Video Editing/Mangling

Reply
 
Thread Tools Display Modes
Old 11-25-2022, 08:03 PM   #1
bd32
Human being with feelings
 
Join Date: Jun 2012
Posts: 332
Default Any plans to auto sync audio from video to other audio in Reaper?

I have constant problems trying to align the video I shoot at the same time as I'm recording multi tracks on Reaper. I brought this up several years ago and learned a few tricks trying to use alt and drag to align bits that were out of sync. Really hit or miss for me. Today I have a mic recording a percussion instrument in Reaper. My camera is recording video and audio. Even within 15 minutes, if I adjust the video to match the start wav image and use alt/drag to align the back, and also do this in the middle it still gets off very quickly.It would be so happening if Reaper developers could just let the computer analyze the wave form from audio track and do whatever it takes to make the audio from the video match. Thanks.

Last edited by bd32; 11-25-2022 at 08:58 PM.
bd32 is offline   Reply With Quote
Old 11-27-2022, 01:06 PM   #2
papagirafe
Human being with feelings
 
papagirafe's Avatar
 
Join Date: Aug 2020
Location: Brasil
Posts: 389
Default

Hi,

Having had little control on video footage in some of my projects, the synchronisation seems very dependent on the equipement used. I would give a shot at re-encoding the recorded audio track to the same parameters/encoding as audio track of the video and look if it makes a difference. If it does then you can then tweak the parameters to improve quality if needed.

Last edited by papagirafe; 11-27-2022 at 02:22 PM.
papagirafe is online now   Reply With Quote
Old 11-27-2022, 05:11 PM   #3
Spirit
Human being with feelings
 
Join Date: Jul 2008
Location: MotherDiskLand
Posts: 154
Default

Quote:
Originally Posted by bd32 View Post
I have constant problems trying to align the video I shoot at the same time as I'm recording multi tracks on Reaper. I brought this up several years ago and learned a few tricks trying to use alt and drag to align bits that were out of sync. Really hit or miss for me. Today I have a mic recording a percussion instrument in Reaper. My camera is recording video and audio. Even within 15 minutes, if I adjust the video to match the start wav image and use alt/drag to align the back, and also do this in the middle it still gets off very quickly.It would be so happening if Reaper developers could just let the computer analyze the wave form from audio track and do whatever it takes to make the audio from the video match. Thanks.
I make long videos (1-hour+) using multiple video cameras and Reaper audio almost every week and the sync is never an issue. Your audio rates are probably mismatched. My guess is you are mixing 44kHz and 48kHz audio.
Spirit is offline   Reply With Quote
Old 11-27-2022, 06:04 PM   #4
Illusion
Human being with feelings
 
Join Date: Jan 2011
Posts: 14
Default

Quote:
Originally Posted by Spirit View Post
I make long videos (1-hour+) using multiple video cameras and Reaper audio almost every week and the sync is never an issue. Your audio rates are probably mismatched. My guess is you are mixing 44kHz and 48kHz audio.
My guess is no, it's not about sample rates. It's because the clocks in the different recording devices isn't running steady. It is common in prosumer devices. However, it could be just one of them, or both.

This isn't mostly going to be a feature in REAPER, but I guess there are external programs that could sync them up. Another option would be to calculate the drift, and pitch the audio recording. But the best option would be to get devices with internal clocks that runs rock solid steady (like the RME Fireface interface that I have).

Last edited by Illusion; 11-27-2022 at 06:09 PM.
Illusion is offline   Reply With Quote
Old 11-27-2022, 06:19 PM   #5
jamesp
Human being with feelings
 
Join Date: Feb 2007
Location: Hampshire, UK
Posts: 328
Default

You need everything locked to a single clock while shooting. There's no way that even the best digital clocks are going to stay in sync over an hour without this.

If you want an easy way to sync things up you could look at stretch markers which allow you to drag the audio to match but the best way sonically is to very slightly adjust the playback speed of the audio items in the item properties dialog. You may need to split the audio into sections with slightly different adjustments for each section but I've synced things up to within a few milliseconds over an hour using this method.
__________________
JRP Music - audio mastering and restoration. https://www.jrpmusic.co.uk
https://www.facebook.com/JRPMus/
jamesp is online now   Reply With Quote
Old 11-27-2022, 08:20 PM   #6
bd32
Human being with feelings
 
Join Date: Jun 2012
Posts: 332
Default

At the minimum these replies point me in the direction I have to go. I was just hoping, since the last time I checked, there might be an automatic way to do this. I have no idea how to code and sometimes it takes all of my ability to even implement some things people do here. If I switch cameras or use my phone it's starting all over again in terms of the format they record in. It's been quite a while since I last tried to sync audio and video and these replies make remember some of the tips I got then.For my level, pretty difficult. I still hope someone will bring auto sync for video and audio, for Reaper, in the future and/or allow me to record video directly into Reaper as I record multi track audio and just let me avoid the whole snyc issue. Thanks.
bd32 is offline   Reply With Quote
Old 11-28-2022, 09:19 AM   #7
papagirafe
Human being with feelings
 
papagirafe's Avatar
 
Join Date: Aug 2020
Location: Brasil
Posts: 389
Default

Quote:
Originally Posted by bd32 View Post
At the minimum these replies point me in the direction I have to go. I was just hoping, since the last time I checked, there might be an automatic way to do this. <snip>
I have seen a lot of discussions about sync'ing multiple audios in audio forums and I haven't seen any automatic option. From experience, it is better to "loosely" sync using audio from the video track to match the pure audio track: the eye is slower than the ear. I would suggest your listen to the Reaper video about transcient guides that will save you a lot of time. Good luck.
papagirafe is online now   Reply With Quote
Old 11-28-2022, 04:46 PM   #8
bd32
Human being with feelings
 
Join Date: Jun 2012
Posts: 332
Default

Quote:
Originally Posted by Spirit View Post
I make long videos (1-hour+) using multiple video cameras and Reaper audio almost every week and the sync is never an issue. Your audio rates are probably mismatched. My guess is you are mixing 44kHz and 48kHz audio.
Well, I kind of learned about that the last time I tried this and all the tricks needed are slowly starting to come back. That's right about mixing 48khz and others in my case. I had two projects with different ones. I thought I'd set project settings in Reaper for 48 to match my camera (which can't be changed from 48khz) but missed one checkbox and got another mismatch. Regardless, yesterday I got all audio recording tracks on 48 to match the video and it's still drifting a lot over one hour. So that was disappointing.I'm trying to familiarize myself with stretch markers now. Thanks.
bd32 is offline   Reply With Quote
Old 11-28-2022, 04:49 PM   #9
bd32
Human being with feelings
 
Join Date: Jun 2012
Posts: 332
Default

Quote:
Originally Posted by jamesp View Post
You need everything locked to a single clock while shooting. There's no way that even the best digital clocks are going to stay in sync over an hour without this.

If you want an easy way to sync things up you could look at stretch markers which allow you to drag the audio to match but the best way sonically is to very slightly adjust the playback speed of the audio items in the item properties dialog. You may need to split the audio into sections with slightly different adjustments for each section but I've synced things up to within a few milliseconds over an hour using this method.
I'm just trying to recall how to use these. I tried a few in the most recent video but it seems I'll need many. In a very general sense, about how many stretch markers might I expect to have to stick in for an hour video? Just to get a rough idea. Thanks
bd32 is offline   Reply With Quote
Old 11-28-2022, 10:54 PM   #10
bd32
Human being with feelings
 
Join Date: Jun 2012
Posts: 332
Default

Quote:
Originally Posted by papagirafe View Post
I have seen a lot of discussions about sync'ing multiple audios in audio forums and I haven't seen any automatic option. From experience, it is better to "loosely" sync using audio from the video track to match the pure audio track: the eye is slower than the ear. I would suggest your listen to the Reaper video about transcient guides that will save you a lot of time. Good luck.
Is this the one you're talking about? https://www.youtube.com/watch?v=GRO-ecLZqmw It gives some info about shortcuts on stretch markers but I wish it dealt with syncing various audio tracks. It seems (as much as I can follow it's higher technical level) about lining up beat rhythms. I wish it was much simpler either through automation program or allowing Video to be recorded along with audio right in Reaper.

Last edited by bd32; 11-28-2022 at 11:05 PM.
bd32 is offline   Reply With Quote
Old 11-29-2022, 04:34 AM   #11
papagirafe
Human being with feelings
 
papagirafe's Avatar
 
Join Date: Aug 2020
Location: Brasil
Posts: 389
Default

Quote:
Originally Posted by bd32 View Post
Is this the one you're talking about? https://www.youtube.com/watch?v=GRO-ecLZqmw It gives some info about shortcuts on stretch markers but I wish it dealt with syncing various audio tracks. It seems (as much as I can follow it's higher technical level) about lining up beat rhythms. I wish it was much simpler either through automation program or allowing Video to be recorded along with audio right in Reaper.
I think so. Basically all you need to do right click on the selected item -> stretch markers -> transient guide -> calculate. That will give you little green floating "potential" markers. Each time you click on one it becomes a stretch marker. Saves time.
papagirafe is online now   Reply With Quote
Old 11-30-2022, 06:48 PM   #12
bd32
Human being with feelings
 
Join Date: Jun 2012
Posts: 332
Default

Quote:
Originally Posted by papagirafe View Post
I think so. Basically all you need to do right click on the selected item -> stretch markers -> transient guide -> calculate. That will give you little green floating "potential" markers. Each time you click on one it becomes a stretch marker. Saves time.
Thanks for the comment. I still am kind of hazy on how this works. Just trying it now. If I line up the two tracks at the beginning by dragging the video's audio and then put in a stretch marker at, for example, 10 seconds later and pull the audio a bit to the left doesn't it affect what precedes it. I don't need to split the tracks at every stretch marker, transient area? Everything on both sides seems to be moving when I move one stretch marker.
bd32 is offline   Reply With Quote
Old 11-30-2022, 08:13 PM   #13
ashcat_lt
Human being with feelings
 
Join Date: Dec 2012
Posts: 6,894
Default

As long as both were recorded digitally, the drift is going to be a constant speed multiplier. You don’t need stretch markers. Line up the beginning, then stretch the video (alt+drag the item) so that the end lines up. Then whatever mark you matched at the beginning will probably be off again, so go back and stretch or slide til it’s lined up again, but then you’ll have to go back to the end and…it can be fiddly and repetitive and annoying, but as long as you’re not actually trying to mix the audio together, it doesn’t have to be perfect down to the sample. Just go back and forth til it’s close enough for you.
ashcat_lt is online now   Reply With Quote
Old 12-01-2022, 12:23 AM   #14
bd32
Human being with feelings
 
Join Date: Jun 2012
Posts: 332
Default

Quote:
Originally Posted by ashcat_lt View Post
As long as both were recorded digitally, the drift is going to be a constant speed multiplier. You don’t need stretch markers. Line up the beginning, then stretch the video (alt+drag the item) so that the end lines up. Then whatever mark you matched at the beginning will probably be off again, so go back and stretch or slide til it’s lined up again, but then you’ll have to go back to the end and…it can be fiddly and repetitive and annoying, but as long as you’re not actually trying to mix the audio together, it doesn’t have to be perfect down to the sample. Just go back and forth til it’s close enough for you.
I'll give this way a try next. Actually the audio from the video adds something useful to the mix. It catches certain sounds the other mic didn't. However, your comment makes me realize that next time I need to set up a room mic because if that video audio isn't perfectly in sync you hear the ricochet sound of it being off. I'll try this different approach without stretch markers for now (at least until I get the hang of them). It can be very technically challenging for my level when reviewing other approaches and the settings you have to keep an eye on.I try to do this thing a few times a year and by the time I get going again I forgot some of the more technical things I almost learned last time. For example...unchecking the box to'preserve pitch when changing rate' in item properties. No matter whhat way I try it seems I have to make a bunch of splits in it. One adjustment at the front and alt-dragging the ends left a huge amount out of sync in 1/2 hour. Thanks

Last edited by bd32; 12-01-2022 at 02:24 AM.
bd32 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -7. The time now is 06:37 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2023, vBulletin Solutions Inc.