12
votes
Timestamps are unset in a packet for stream 0. This is deprecated and will stop working in the future. Fix your code to set the timestamps properly
The usual solution for this situation: -fflags +genpts
It should eliminate the warning, but there's no guarantee your sync issues will be solved.
- 221
9
votes
Accepted
ffmpeg concat introduces a/v sync problem
Run
ffmpeg -i titlefile.mp4 -vf setdar=16/9 -video_track_timescale 29971 -ac 1 newtitle.mp4
and then run concat with the new title video.
Modern containers like MP4 have Presentation TimeStamps, ...
- 32.6k
7
votes
Remove flickering due to artificial light with ffmpeg
The following worked well for me, based on the same ideas
http://www.premiumbeat.com/blog/quick-trick-for-de-flickering-your-video-shots/
https://superuser.com/questions/1025794/merge-two-videos-...
- 71
5
votes
Accepted
By how much can video and audio be out of sync?
There are, in fact, several standards on audio/video or lip sync. The problem is, they can't all agree on what the acceptable error is. What is well understood is that if the audio lags the video it ...
- 2,405
4
votes
Sync several movie clips with one audio file
This sounds like a perfect candidate for using multi-camera editing. You can automagically synch all the clips using their audio, and turn them into a multicam source, which lets you edit from the ...
- 13.7k
4
votes
Accepted
What is the best way to plan and sync voiceover?
In addition to @Mulvya answer I will suggest to use not Flash, but After Effects for animation, if possible. Then you will be able to make Dynamic Link to your AE project. Than will be easier to jump ...
- 1,729
4
votes
Accepted
Timestamps are unset in a packet for stream 0. This is deprecated and will stop working in the future. Fix your code to set the timestamps properly
this worked for me as an option to ffmpeg: -use_wallclock_as_timestamps 1
- 323
4
votes
Accepted
ffmpeg to cut subtitle file in sync with the cut video
Found out that ffmpeg works on the text based subtitle file just as well:
$ cat subtitles.srt
1
00:00:06,000 --> 00:00:20,000
This is demo subtitle 1
2
00:00:20,000 --> 00:00:40,000
This is ...
- 185
3
votes
Accepted
Audio without video is OK, but WITH video it is delayed
You've to reset the timestamps:
[1:a]atrim=start=2.52:end=1:38.0,aloop=100:7700,asetpts=N/SR/TB[audio]
- 32.6k
3
votes
Accepted
Syncing audio and video from different sources
This is a rather common problem. The issue is NOT sample-rate. And the issue is NOT frame-rate, either. Most modern editing software (or file-manipulation software) is capable of easily resolving ...
- 686
3
votes
Accepted
Is it possible to capture video signal waveform as audio for video replay?
The short answer to your question is "no". The sample rate of video is typically measured in MHz or GHz. If you have a 1080p24 signal at 8 bits per pixel, the actual frame is 2750 x 1125 pixels (...
- 4,730
3
votes
Accepted
OBS Studio: desktop audio falls out of sync
So with everything I've tried I'm not sure if I messed anything up, but....
Turning off "Use device timestamps" in the properties of "desktop audio" fixed the problem.
- 141
3
votes
Accepted
Sync Video to Audio in SonyVegasPro13 with multiple anchors
Short Answer
Split your Video track into separate Events;
Adjust the Events individually by dragging them along the timeline and stretching/expanding them;
Overlap the adjacent Events so that there ...
3
votes
What is the best way to plan and sync voiceover?
If the audio is primary and the visuals convey or complement the narration, then record the audio first. Use the audio timings to guide the pacing of your animations - if some demo takes longer than ...
- 32.6k
3
votes
What causes audio sync drift when digitizing VHS?
Audio drift can have a couple of causes, dropped frames (which a TBC can help with), and unstable clocks, where the audio isn't recorded at quite the precise rate it should be, causing drift, as ...
- 687
3
votes
Accepted
How to combine multiple audio tracks without sounding blasted?
When you record each track, make sure that the level never goes up to zero on the meter. If it hits zero, it means that the recording is clipping. Clipping is when the computer can no longer ...
- 7,585
2
votes
Losing audio/video sync in Adobe Premiere with mp4's
I had the same issue on Windows 10 with a Variable Frame Rate (VFR) video recorded using Shadowplay. Here's how I fixed it without requiring to convert the video using Handbrake or any other converter:...
- 121
2
votes
Losing audio/video sync in Adobe Premiere with mp4's
I would strongly suggest that you don't work with mp4/H264 files for sync-sensitive work. Transcode the files and work with those.
- 686
2
votes
Losing audio/video sync in Adobe Premiere with mp4's
Download the 32-bit static build ffmpeg from here and try either of the two methods:
1) regenerate the timestamps
ffmpeg -i input.mp4 -c copy -fflags genpts new-input.mp4
2) Extract audio, import ...
- 32.6k
2
votes
Sync several movie clips with one audio file
Premiere and FCP-X both have auto-sync features to get multiple audio and video clips synced together. Chances are very good that you can get your first video clip to align with the audio clip ...
- 4,730
2
votes
Sync several movie clips with one audio file
Create a timeline from the master audio track, then drop the video clips one by one onto a matching video track using the native sound from those clips as a guide to line them up with the good audio. ...
- 4,674
2
votes
Accepted
How is 29.97 timecode generated over a full day without frame errors?
As per the Broadcast Engineer's Reference Book, p. 203
This correction will match DF time to real time to within
approximately 2.6 frames per day; to eliminate the residual error the
timecode ...
- 32.6k
2
votes
Accepted
Rolling shutter strobe pattern
No matter when the camera shutter is active, if the frequencies of the video vertical timing (the frame rate) and the laser pulse are not congruent, you'll see partial exposures as they drift apart.
...
- 4,674
2
votes
Resynchronizing audio in a variable framerate video with missing timing data
No matter how you slice it, this sounds like it's going to be painful if not impossible, mostly because you say the rate changes dynamically. My best suggestion would be to use a software like Adobe ...
- 829
2
votes
Accepted
Subtitles do not match spoken dialogue. Why?
This is an educated guess as I'm not sure anyone can give a concrete answer as to this particular show's specific reason, but since it was dubbed, there's a solid possibility that the subtitles are a ...
- 19.3k
2
votes
Timestamps are unset in a packet for stream 0. This is deprecated and will stop working in the future. Fix your code to set the timestamps properly
This error can also be eliminated in some situations (VFR source files with unusual timebases) by using -vsync 0 -enc_time_base -1
2
votes
Audio/video sync software for Linux (preferably open source)
I assume that you have a sound channel recorded on the camera which is in sync with the picture. In that case you only have to find the offset between the audio channels.
This tool claims just that: ...
- 121
2
votes
Accepted
Add timecode information to file
@Gyan gives the answer in comments:
MP4s and MOVs store only the TC of the first frame, as a literal frame count, along with the framerate. The consuming app converts that frame count back to a TC ...
- 241
2
votes
What causes audio sync drift when digitizing VHS?
No, a TBC won't solve an audio-video sync problem. Most likely the sync problem is coming from a shortcut in the capture device or driver that samples the audio and video with separate and/or unstable ...
- 2,405
1
vote
Accepted
Syncing Multiple Audio Streams With One Video Stream (FFMPEG)
Just thought I'd let you guys know that I got this working.
I needed to use -framerate instead of -r to get it to duplicate dropped frames, the reason I wasn't using -framerate in the first place is ...
- 121
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