Ffmpeg audio sync drift Built on FFmpeg, it handles direct data copy operations Is there no > > way to record audio and video from different sources, and just use "wall > > time" or "time elapsed since executing ffmpeg" to sync up the audio / > > video? > > You can try If you try 'ffmpeg -i complaint. The video is going to fast, and audio is good. Here's some of the options I've I have a video in 1080p but for some dumb reason, the audio is only stereo. This appears to put things back together in synchronization, because after this I can use ffmpeg or Avidemux or anything else I've tried and the video and audio appear to be in sync. ly/BW-ColorGradingMasterclass🔥 Learn more & get all my free stuff here → https://bit. I'm fine with gaps, pauses, missing audio, etc in that small portion . Read our advanced CLI guide now! This document discusses how to use FFmpeg to fix common audio and video sync issues. When I try to transcode this file into something more manageable, ffmpeg makes the audio drift. The I am having an issue and am not sure if I am allowed to ask here. It becomes the best choice to convert, compress and I've tried several ffmpeg sync settings (vsync & async -1/1/2) which can be applied with the asset after its own applied ffmpeg settings (which are sent together to start up ffmpeg streaming), but they did Audio sync issue Hi Reddit! I have the problem that sometimes my audio is slightly out of sync. I use ffmpeg to ffmpeg reads the video from /dev/video1, and the audio from tcp://localhost:55555. txt -c I'm using ffmpeg to record NTSC analog video on Linux Fedora 36 using a Blackmagic Intensity Pro 4K for video and a Scarlett 2i2 for audio. I don't think I need anything quite that fancy. But the question is how do I find exact Discover effective solutions to resolve video/audio sync issues when using `ffmpeg` for concatenating videos. Goal is to put intro. Learn how to fix audio sync problems during video merging with FFMPEG by using the `-max_interleave_delta 0` flag, ensuring a smoother Using concat and encoding the video seems to work fine. Follow this step-by-step guide for Linux, Windows, and MacOS. This works almost perfectly; but the problem is that over time, the video and audio drift apart from Best and kind regards, -Tracey // **hopefully** the near ultimate fix for MPEG-TS A/V sync drifting! // Make sure we use "-vsync" param. The problem is that video is not in sync with audio. How can I fix the video stream using ffmpeg. I also have the same video in 480p but the audio is 5. I'm using a TBC to avoid dropped frames and but the file that is generated doesn't match the exact timestamps (I think this is because the file is cut at the keyframes right, in which case this isn't really an issue) and there is no audio at the start of For those that are wondering why I am using ffmpeg instead of another tool, here is some more information: 1. I also tested it and it works. Source PDR, it's not the B-frames that cause sync issues in AVI but B-pyramid. Having a problem installing a new Well, let me show you how you can quickly, and easily fix subtitles. However final video is out of sync. Fix AV sync drift and automate your pipeline. We are pushing an rtmp stream to our nginx+ffmpeg transcoder. The origin stream play fine and stays in sync. But the sound seems to go out of sync in the sequence (the inividual This guide addresses common audio sync problems that occur when splitting and merging video and audio files using FFmpeg. It explains that audio can be either too fast or slow compared to the We are pushing an rtmp stream to our nginx+ffmpeg transcoder. At the start it's not really perceptible, but within even 20 minutes it's extremely bad -- perhaps Is the audio offset consistent throughout? That is, check say, 3 spots, one near the beginning, one in the middle, and one near the end, and estimate what the amount of offset is. First parts are coming from static image which are converted to 5 Users report difficulties with FFmpeg's audio sync when concatenating multiple audio files. So I'm not 100% sure what "wallclock" is compared to "non wallclock"; but in this case The new video file looks and sounds fine but as the video plays the audio drifts out of sync and I don't know how to keep in in sync. Handbrake aligns the video and audio, but has similar sound blips as using async with I need to concat these files, but after I run the concat, all video after that problematic 10s file is out of sync with the audio. Practical examples for fixing A/V sync problems. Learn how to fix these issues for optimal video 1 you need to delay all the audio channels with the same value using adelay=milliseconds:all=true, and use -async 1 at the end of your command so ffmpeg will just ffmpeg reads the video from /dev/video1, and the audio from tcp://localhost:55555. Video has strange frame rate: 26. I tried some suggestions, like using I am trying to concatenate multiple files together using ffmpeg concatenate demuxer. However, simply concatenating the I have one 2-hour video file and want to add a 10-second title sequence to its start. Also, the script is using ffmpeg to launch the streams. That I'll figure out, using FFMPEG's timeline editing filter. Verified ffmpeg 6. What kind of sync problem do you have? How do you combine audio and video? You have to be sure that explicit sample and frame rates are correct, and match the original, otherwise Why is FFmpeg not reading the video stream itself? Why is the pipe (that makes keeping A/V sync probably impossible) necessary? > At the beginning audio & video are in sync but slowly but Learn how to merge video and audio of different lengths with FFmpeg. After me. This works almost perfectly; but the problem is that over time, the video and audio drift apart from eachother. Of course, just like last time, "out of sync" I am trying to add two videos using ffmpeg and the output video/audio is out of sync (and fast forwarded). I've tried recoding the whole file using both Handbrake and FFmpeg. I've got a video file that has and e-ac3 audio track and i've extracted it using VLC as a wav file, i've run the following The reason I bring this up is because there's a considerable audio sync drift in that video. Since the drift rate is constant, you can use a combination of FFmpeg filters to retime the audio. mp4 -y I want to fix these slow motions and make it synced with audio with ffmpeg or if not possible I want to tell ffmpeg to cut those slow frames along with audio channel so video and audio FFMPEG audio out of sync when transcoding (demuxing) from DV Ask Question Asked 10 years, 1 month ago Modified 6 years, 1 month ago This article discusses solutions to out-of-sync glitches encountered when using FFmpeg's concatenate filter and cut segments. Check the frame rate for both, check the audio sampling frequency for both. i have tried below two link/so answer by Mulvya, but none of them work :( here is the code i am Can FFmpeg sync audio and video directly?" --- A question from SuperUser FFmpeg is a free and open-source programming project consisting of a set-up of libraries and projects that takes care of video, sound, and other media documents and streams. The audio stays in sync as ffmpeg does the full conversion calculations and seems to get everything right. I configured my setup from scratch and I cannot say what exactly fixed the I need an ffmpeg script to shift the audio or video by a specific fraction of a second to correct an out-of-sync problem in an mp4 file with standard stereo audio. I am hopeful someone can offer Fix audio-video sync issues with FFmpeg: when to use -itsoffset, adelay filter, and -async. Ever since there was a fall-out and the ffmpeg developer community split in two (forking ffmpeg into I have a problem saving a streaming with ffmpeg. I had been having My tests with long running streams are showing minor drift back and forth around proper sync, but no long-term desync using my patched ffmpeg copy that passes the hardware timestamps straight After a lot of frustration and several hours of wasted time for testing I quit and tried again some days later. So we're going to set a minimum number of consecutive calls to the synchronize_audio function that have to be out of sync before we bother doing anything. e. Nginx forwards the stream and transcodes it to 2x lower Learn how to synchronize two audio streams using FFmpeg when the talk track and soundtrack are out of sync. org > Forums > Linux Forums > Linux - Software [SOLVED] ffmpeg audio/video sync issues Linux - Software This forum is for Software issues. However, when I use ffmpeg -f concat -i mylist. I've merged several videos taking the 1080p video from The ffmpeg command is left untouched the whole time, only the piped command is changed. After searching on Internet, I found that this can be fixed using itsoffset switch in ffmpeg. I think I I am recording the desktop with gdigrab and the audio with dshow, but they are out of sync. Here is my setup. The problem is the left- I've also read from the ffmpeg resource regarding seeking and copying: Which leads me to believe that maybe because ffmpeg is using timestamps instead of frames, seeking isn't accurate I've also read from the ffmpeg resource regarding seeking and copying: Which leads me to believe that maybe because ffmpeg is using timestamps instead of frames, seeking isn't accurate Maybe VLC is choking on screwy timestamps? FFmpeg 5. ly/m/BradWe I am using FFmpeg's built-in gdigrab & dshow to record the display & audio of my system. My question is about whether there is a way to detect if the audio I bring the video in using raspivid and mix in the audio via ALSA and combine it all and stream using FFmpeg. I am encoding to uncompressed H. I have identified the times of audioA and videoA and audioB and videoB. Read our advanced CLI guide now! 🔗 Get Better at Color Grading in 90 minutes → https://bit. x changed how it handles timestamps when trimming videos. Is it possible to use ffmpeg to encode I have a tool that spits out video from a 3D application and then concats the individual videos to make a sequence. This lets me suppose that when the output buffer is completely filled, the input buffers will get filled, but one of A note on your specific problem: have you considered possible different driver and frame-per-second encoding issues? Seldom you can rule out the problem if this is the cause, by first I am using ffmpeg to live stream video from a Decklink SDI card, and audio with DShow (Dante Virtual Soundcard), and packaging it into an fMP4 HLS livestream. If it's different over time (a Long-term sync issues between audio and video in %ffmpeg #1091 Closed dhannyz opened on Feb 13, 2020 FFMPEG: audio out of sync Ask Question Asked 5 years, 5 months ago Modified 5 years, 4 months ago The ffmpeg developers and their libav antipodes are engaged in a healthy battle. To fix them, you have to use the I guess this has something to do with ffmpeg. In the beginning everything sounds fine, but slowly the audio goes faster than the video. E. mp4 before the original file clip. This is the first thing I tried, there was always about the same delay (about 20-30 frames): // After updating to Mint 21 (aka Ubuntu 22. flv complaint. if the audio is 5 seconds behind at 1 min video, is it 10 seconds behind at 2 min? They key thing to check is the rate of drift at various points. 📊 Michael, I'm focusing on rtmp at the moment. If your audio goes out of sync by the end of your edit. My sources are LosslessCut FFmpeg-Powered Media Editor Perform ultra-fast lossless trimming, cutting, and merging of video and audio files with LosslessCut. flv My approach is to Change the I'm using FFmpeg to record a virtual X11 screen in automated tests. 04) ffmpeg capture with x11grab using -f pulse results in audio out-of-sync with video by a few seconds. problem: Splits may occur before i am having issue, to concat video, it looses the audio sync and audio started from previous video. I try by removing and editing options but It has audio/video synchronization problems. Initially I am having serious audio and video synchronization problems with ffmpeg when trying to either record or stream live screen capture and audio capture. Her is what I try to do: First, I decode a video into single frames: ffmpeg -vsync 0 -i video. Let's Video and audio out of sync after stream recording Ask Question Asked 5 years, 11 months ago Modified 5 years, 11 months ago I'm encountering a problem when using FFmpeg to stream a stereo soundtrack (audio-only) from (internet-)location A to B. Storing B-frames in AVI is trivial with hacks but there's no way to use B Tutorial for fixing audio drift in videos when syncing audio recorded on an external recorder. g. Some of them are not explained very well in the documentation, and many websites have Audio/video gets out of sync significantly in the resulting file, most noticeably on the right-side video. I've added a timestamp to the video to align it with log file times, but the clock in the video becomes out of sync I'm not asking about how to fix an audio video sync issue or lag. 1. The video comes 2-3 seconds before the audio. At the The options -vcodec copy and -acodec copy instruct FFmpeg to directly copy the video and audio bitstreams into the output file, without re-encoding. After some research, I've learned that this might be due to timestamp differences between the Directly downloaded. My problem is the audio and video are out of sync, and seem to drift. I think the audio skips I'm getting from the -async option are I've encountered an issue with a video file where the audio and visual streams are out of sync. 07 fps. I'm The ffmpeg program has numerous “switches” that help to adjust and convert audio and video files. Recently I did a re-encode using ffmpeg and encountered an inaudible but waveform visible audio desynchronization in the process. As far as I can tell, the desync is progressive - it's getting obvious in the middle, and by Is the sync drift linear i. Most of the archives are webm video and audio together. The audio file is the same length as the video, they should be a 1:1 After removal, the finshed file has synced audio at the start, but by the end (an hour or two later), it can be as much as 3 to 5 seconds off, it's a gradual drift. Nginx forwards the stream and transcodes it to 2x lower quality streams. mp4', does is it still out of sync? Is the original file out of sync when you play it in VLC? Description Hello, video/audio sync drift while doing real time recording with mp4 or mkv while with ffm it's totaly fine I know there's a ton of questions on here about video and audio being out of sync when using ffmpeg, however I couldn't find a single one that solved my problem, so I'm hoping you all can help. Learn how to fix the issue by under If the audio is recorded separately from the video (edit: or if there are 2 or more video angles) then even on the very best cameras the sync will drift based on Fix audio drifts in video records with Kdenlive and FFmpeg Dec 03, 2017 Audio Video I recorded some old VHS tapes to digitize them to video Fix audio drifts in video records with Kdenlive and FFmpeg Dec 03, 2017 Audio Video I recorded some old VHS tapes to digitize them to video I have a series of videos with the audio going at the wrong speed and not starting in the correct place. Learn step-by-step techniques to LinuxQuestions. Unlock Perfect Sync: Master FFmpeg to Align Audio & Video Durations in MKV Files Seamlessly match your MKV audio and video track lengths with these powerful FFmpeg techniques. Name of the game: ffmpeg In general, in life, if in doubt, and you're Tried "stretching" the audio with FFMpeg using "aresample=async=1000", which synchronises but the audio is distorted. I didn't force pulse to use wallclock, I just told it to use pulse for audio and now it seems to stay in sync. 264/AVC video & uncompressed PCM/WAV audio. Learn how to merge video and audio of different lengths with FFmpeg. This issue persists across various players, but is more noticeable in some than others. The long file has perfect a/v sync from start to finish. // This came about from ~Dec 2012 "new" TV programs that were Drift in audio synchronisation when converting from one audio track to another. Make sure they're the same or you'll have to include that in your calculations. \