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Questions tagged [audio-video-sync]

Questions related to synchronization between audio and video during creation, transmission, reception and playback of content with both audio and video.

Audio to video synchronization (also known as audio video sync, audio/video sync, AV-sync, lip sync, or by the lack of it: lip sync error, lip-flap) refers to the relative timing of audio (sound) and video (image) parts during creation, post-production (mixing), transmission, reception and play-back processing. When sound and video have a timing related cause and effect, AV-sync can be an issue in television, videoconferencing, or film.

More details at http://en.wikipedia.org/wiki/Audio_to_video_synchronization

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FFmpeg - What does non monotonically increasing dts mean?

Observations - Part - I I saw a suggestion elsewhere to run the following command to see if there's something wrong with my .mp4. ffmpeg -v error -i ~/Desktop/5_minute_sync_output_15mn.mp4 -f null - 2>error.log When I run the above command, I see…
Mukund Manikarnike
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iOS AVFoundation audio/video out of sync

The Problem: During every playback, the audio is between 1-2 seconds behind the video. The Setup: The assets are loaded with AVURLAssets from a media stream. To write the composition, I'm using AVMutableCompositions and AVMutableCompositionTracks…
Tyler Kendrick
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Combining an audio and video stream using gstreamer

I am streaming an mp4(mpeg-4) file from one device to another using gstreamer over RTP stream. Basically I am splitting up the mp4 file into its audio and video file and then sending it all to the other device where it gets streamed. Now, I want to…
user1795516
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How to combine audio and video in Pytube?

I am trying to write a code to download YouTube videos using Pytube on Python 3.6. But for most videos progressive download(Audio and Video in same file) format is available only upto 360p. So I want to download audio and video files separately and…
Nikith Clan
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Audio Video Sync With ffmpeg

I have very strange video file. It has audio/video synchronization problems. The video is going to fast, and audio is good. Video has strange frame rate: 26.07 fps. How can I fix the video stream using ffmpeg. At the start of the video the sync is…
Marcin Kapusta
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How To : Create Video chat using gst and python and show initiators and accepter's video, in single gtk window

I am developing video chat using gst and python. where, I would like to view end user's webcam and also want to view my own webcam in one gtk window (similar to empathy video chat). for that, I have used gst.Tee object and created 2 queues, one…
Yajushi
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WebRTC: Synchronize video frames between JavaScript and Native Code peers

It follows the design I'm trying to implement a proper way: I have a JavaScript peer that is sending a video track to a Native Code peer. At some point during the transmission (actually immediately after the connection has been established, but it…
ceztko
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How to keep audio and video (GEM) synchronised?

Here is the setup: I have a video file and an audio file with the same duration. The video file is played with [pix_film] and the audio file via [readsf~], both are then distorted by several effects, triggered by user interaction. How can I keep the…
Residuum
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Syncing decoded video using Ffmpeg

I am using Ffmpeg to decode and play video files. I have currently got the video playing and the audio playing at as fast as the CPU can decode and display them. The problem is that I want to play the video and audio in sync using the system…
Infiniti Fizz
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A/V sync issue - Apple's HTTP Live Streaming

When I try to stream TS chunks generated by 3rd party multiplexers (Mainconcept/Elecard) from Safari browser in IPad 2.0/1.0 I always see Audio Video synchronization issue over a period of time. But the same clips are playing fine in standard media…
ifreeman
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Is there a higher level API for Xuggler?

After downloading and using Xuggler, my initial impressions are very good; it supports a whole host of codecs, it was relatively hassle free to get going and the getting started tutorial videos explained all the necessary concepts very…
Michael Berry
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how to merge audio and video file in python using ffmpeg?

I am trying to create a python script which merge the audio and video file in one (audio+video) file. And i am using ffmpeg to achieve this but it is not working and i am getting a errors. while running this script here is my script. import…
arvind8
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Media Foundation video re-encoding producing audio stream sync offset

I'm attempting to write a simple windows media foundation command line tool to use IMFSourceReader and IMFSyncWriter to load in a video, read the video and audio as uncompressed streams and re-encode them to H.246/AAC with some specific hard-coded…
m1keall1son
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Delay issue in Audio/Video Merging through Python

I am writing a program in python on RaspberryPi, to record video on a Picam and capture audio through a Microphone attached with USB AUDIO DEVICE. On combining both files through ffmpeg, till 30sec both Audio/video synchronize well but after 30sec,…
Fahadkalis
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ffmpeg video-concatenation - audio-/videotrack Synchronisation

I'm want to concatenate different video-files of random format. First I convert them to flv, adapt the framerate of each video to lowest of the involved videos. Next step is to decode them and remove the header (but not the header of the first video…
user1739223
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