Sync - Resample audio from video source of 29 FPS to 25 FPS

[Chastepe]

Hi, I have two camcorders one of them records in 25 FPS and the other one in 29 FPS. I want to edit a 2-cam footage using these two cameras, but I will use as main audio the sound from the camcorder that records at 29FPS. The other camcorder's sound will be used as a reference. My question is: If I extract the audio from the 29FPS Camcorder and stitch it to the video with 25 FPS, will the audio be synced? If not, how can I fix this problem and convert the sound to fit with my 25FPS footage? Thanks a lot.

[poisondeathray]

Audio doesn't have an FPS

The 2 audio tracks should approximately be in sync, if they are not genlocked to the same signal you can get audio drift. Over short durations it might not be noticable, but audio drift over long durations will be noticable . To check, you can line up the audio tracks and compare the waveforms in an audio editor or NLE - they should be fairly close

[Chastepe]

If the audio drifts as you said, is there any way to fix it? Thanks

[poisondeathray]

If it drifts, you have to manually sync it in an editor. This can be very painful, or if you luck out , it might be a breeze

[pandy]

Audio length and video length must be the same - if audio length is same as video length and same on both recording i see no source for audio drift unless there is somewhere error. Or in other words - both audios shall be perfectly exchangable when both video (and audio) tracks have same play time.

[Cornucopia]

The problem the OP is going to have is that in order to edit the 2 cameras' footage together, ONE of those camera's video is going to need a framerate conversion (FIRST). Depending upon how the conversion goes, it could necessitate stretching/shrinking of the time (plus, pitch correction if desired/needed) which makes the whole job a LOT more complicated.

You really should re-think your whole 2-camera setup and try to go with 2 cameras that use the same system (either PAL/25 or NTSC/29.97) - maybe too late for this shoot, but not for future shoots. If you live in Manchester, UK it should be PAL, if Manchester, N.H., USA it should be NTSC...

Scott

[pandy]

If i understand correctly - those two cameras are intentionally different and they will be used to comparison (one of them as a reference) not sure on this however - my point is that if they (camera's) recording at the same time moment then audio same length can be used independently (not sure why but it is up to the OP)