Aligning video to audio

When you import a video, LTCast automatically aligns it by comparing the video's internal audio track to the loaded audio file using waveform matching. The result is an offset value that tells LTCast where the video start sits relative to the audio.

Auto-alignment

Auto-alignment runs immediately after import. LTCast extracts the audio from the video file and slides it against the loaded audio track, looking for the best-matching position. The resulting offset is shown in seconds in the Video Reference panel.

If the result looks wrong or the confidence is low, click Re-sync to audio in the video panel to re-run the comparison from scratch.

The Waveform Compare dialog

After import, a dialog shows the loaded audio waveform and the video's audio waveform overlaid. You can drag the video waveform left or right to slide its alignment. The offset value updates in real time as you drag. Confirm when the waveforms are visually aligned.

Manual offset adjustment

In the Video Reference panel header, the current offset is shown as a number. Click the field to type a specific offset value in seconds. Positive values move the video forward; negative values move it backward relative to the audio.

Frame nudge

For precision fine-tuning after auto-align or manual adjustment, use the ±1 frame nudge buttons. See Frame nudge for details. The offset value updates by exactly one frame per press, based on the project's current frame rate.