Find Audio Delay

[sirbubby]

Hello,

Started using MKVToolNix last night and I love it. Great program! The audio on my mkv file is delayed and I wanted to find out the exact milliseconds. Is there a program that will tell you? I didn't see it in MKVToolNix.

Thanks

[hello_hello]

I do it visually with MPC-HC. Open the MKV, make sure the View/Status menu is checked and while the video is playing use the plus and minus keys on the numeric keypad to adjust the audio delay. When you're happy with the sync, make note of the delay displayed in MPC-HC status bar and set it as the audio delay when remuxing the MKV. It can be positive or negative.

[manono]

The audio on my mkv file is delayed and I wanted to find out the exact milliseconds.

You can't. If you're lucky you might get it to within 40-50ms. One way is to use a player with which you can adjust the delay on the fly. One such player is MPC-HC. Use the + and - keys to adjust the delay in 10ms increments. I think I can probably get it to within 20-30ms using an AviSynth filter that shows the wave form with the video picture.

Edit: hello_hello beat me to it.

[sirbubby]

I do it visually with MPC-HC. Open the MKV, make sure the View/Status menu is checked and while the video is playing use the plus and minus keys on the numeric keypad to adjust the audio delay. When you're happy with the sync, make note of the delay displayed in MPC-HC status bar and set it as the audio delay when remuxing the MKV. It can be positive or negative.

I've read about doing with VLC and MPC. This is a last resort for me. I'm muxing a video from one file with audio from another. The video on one of the files has added screens to the beginning compare to the other so I was trying to find the audio delay on the file I'm using the video. I just need to know when to start the other audio track.

[JVRaines]

You will be up to 40 milliseconds early or 90 milliseconds late trying to find the offset by lip sync. You need to view the video in an editor where you can step through frames with concurrent audio waveform display. Then you can match the waveform to a sharp audiovisual cue like a door slamming shut. I have done this in Vegas.

[sneaker]

I do it visually with MPC-HC. Open the MKV, make sure the View/Status menu is checked and while the video is playing use the plus and minus keys on the numeric keypad to adjust the audio delay. When you're happy with the sync, make note of the delay displayed in MPC-HC status bar and set it as the audio delay when remuxing the MKV. It can be positive or negative.

I've read about doing with VLC and MPC. This is a last resort for me. I'm muxing a video from one file with audio from another. The video on one of the files has added screens to the beginning compare to the other so I was trying to find the audio delay on the file I'm using the video. I just need to know when to start the other audio track.

Open both files in a video editor (like virtualdub), go to an identical frame in both and subtract the timecodes.

[sirbubby]

I do it visually with MPC-HC. Open the MKV, make sure the View/Status menu is checked and while the video is playing use the plus and minus keys on the numeric keypad to adjust the audio delay. When you're happy with the sync, make note of the delay displayed in MPC-HC status bar and set it as the audio delay when remuxing the MKV. It can be positive or negative.

I've read about doing with VLC and MPC. This is a last resort for me. I'm muxing a video from one file with audio from another. The video on one of the files has added screens to the beginning compare to the other so I was trying to find the audio delay on the file I'm using the video. I just need to know when to start the other audio track.

Open both files in a video editor (like virtualdub), go to an identical frame in both and subtract the timecodes.

That's a good idea but that program wont let me open mkv hevc videos.

I used VLC and watched the time when the two movies start. One starts about 18500ms before the other. They are both the same movie and run at 24fps but for some reason as the movie goes on the audio starts to get ahead of the video. It was synced when it first started.

[manono]

I used VLC and watched the time when the two movies start. One starts about 18500ms before the other. They are both the same movie and run at 24fps but for some reason as the movie goes on the audio starts to get ahead of the video. It was synced when it first started.

So, it seems to me your goal to synch it to the exact millisecond is more of a pipe dream than you imagined.

Maybe one is really 23.976fps and the other really 24fps? That would create a difference of roughly 3.5 seconds every hour, if memory serves. Or maybe one version has slightly different content than does the other, once that 18.5 seconds is taken into account. A frame here and a frame there, at scene changes, and pretty soon your audio synch flies out the window.

[sirbubby]

I tried this again using mpc-hc instead of vlc. I noticed the audio delay was about 19500ms this time in stead of 18500ms. I watched it back using mpc-hc first and had no issues at all. I then played it back on my nvidia shield and had some artifacts at the start and the audio dropped once but came back after a second. It's not prefect but it'll do. I don't have issues with any other 4k movies though. Thank everyone for the help!