Even the best translation is useless if the timing is off. AI Subtitle Studio provides a high-precision Timeline Editor that allows you to sync subtitles to audio with millisecond accuracy.
1. The Visual Sync Interface
The editor uses a multi-layered approach to help you “see” the timing of your subtitles.
- Audio Waveform: The studio generates a visual waveform of the video’s audio track. This allows you to see exactly when a character starts speaking (peaks) and stops (valleys).
- Active Highlight: As the video plays, the current subtitle block is highlighted in green on the waveform. If the highlight doesn’t match the audio peak, you know you need to adjust.
- Real-time Playback: Use the built-in player to listen to the dialogue. You can use Space to play/pause and J/L keys to skip backward or forward by 5 seconds for quick checking.
2. Tools for Precision Syncing
Waveform Dragging
The most intuitive way to sync is by interacting directly with the waveform.
- Shift Timestamps: You can click and drag the edges of a subtitle block on the waveform to expand or shrink its duration.
- Move Entire Blocks: Drag the center of a block to move both the start and end times simultaneously while keeping the duration identical.
Keyboard Shortcuts for Speed
For professional editors, the studio supports “Hot-key Syncing” to keep your hands off the mouse:
[(Left Bracket): Set the Start Time of the current subtitle to the current playhead position.](Right Bracket): Set the End Time of the current subtitle to the current playhead position.Up/Down Arrows: Quickly jump between the previous and next subtitle blocks.
3. Advanced Sync Features
Automatic Overlap Prevention
When you manually adjust a timestamp, the editor automatically checks if you are bumping into the next subtitle. It prevents “illegal” timings where a subtitle starts before the previous one has finished.
Waveform Zoom
If you are dealing with fast-paced dialogue, you can use the Zoom Slider (located below the waveform) to stretch the audio view. This allows you to pinpoint the exact millisecond a sound begins.
History & Undo
Syncing can be trial and error. The studio tracks every timing change you make. If you accidentally shift a block too far, you can use Cmd/Ctrl + Z to undo your last action or Cmd/Ctrl + Shift + Z to redo it.
4. How to Save Your Progress
The editor tracks the “cleanliness” of your file:
- Unsaved Changes: A yellow “Unsaved edits” icon in the footer alerts you if your new timings haven’t been written to the file yet.
- Exporting: Once synced, the studio generates a standardized SRT file. It automatically ensures the time format uses the correct SRT standard (e.g.,
00:00:01,000with commas instead of periods) to ensure compatibility with all TV and media players.