AudioSynchro

audioSynchro takes the French dubbed audio track from one video and lines it up with the English video it was dubbed from, so the sound no longer drifts away from the picture. You drop in the two videos and it finds the offset by analysing the audio signal with FFT cross-correlation, and it shows a confidence level for the sync it found.

There are two modes. Series applies a constant offset, which suits episodes. Film also corrects the gradual drift that some dubs have over the length of the video. You can fine-tune the result by hand with a ±10 second slider and precision buttons.

The original video is never re-encoded: its stream is copied bit for bit, so the export is quick and lossless. The output can be saved as MKV or MP4 in the folder you choose.