Timing Rules
Three fundamental parameters determine whether a subtitle is properly timed: reading speed, duration, and gap with the next subtitle. Scene Cut checks these three criteria continuously and flags any violation.
Reading Speed (CPS)
Reading speed is measured in characters per second (CPS). It is the ratio between the amount of text and the display time. A CPS that is too high means the viewer won't have time to read.
| Profile | Minimum CPS | Maximum CPS |
|---|---|---|
| ATAA Cinema | 4 c/s | 15 c/s |
| Netflix | 4 c/s | 17 c/s |
The CPS indicator is visible on each subtitle in the list. It changes color when a threshold is approached or exceeded:
- Gray — speed is within limits
- Orange — speed exceeds the allowed maximum
- Red — speed greatly exceeds the threshold (beyond 110%)
Cmd + K) automatically adjusts the duration to stay within limits.Duration
Each subtitle must remain on screen long enough to be read, but not so long that it disrupts the editing rhythm.
| Profile | Minimum duration | Maximum duration |
|---|---|---|
| ATAA Cinema | 16 frames (~0.67 s) | 5 seconds |
| Netflix | 20 frames (~0.83 s) | 7 seconds |
The minimum duration is also tied to CPS: even a very short subtitle cannot go below the time needed for the text to be readable at the maximum allowed speed.
Gap Between Subtitles
A minimum gap between two consecutive subtitles is necessary for the viewer to perceive the change. Without this gap, two back-to-back subtitles are perceived as a single block — the eye doesn't "reset" for reading.
| Profile | Minimum gap |
|---|---|
| ATAA Cinema | 4 frames (~0.17 s) |
| Netflix | 2 frames (~0.08 s) |
In the subtitle list, the gap between each entry is displayed in milliseconds. An insufficient gap or an overlap appears in red.
Customizing the Rules
All these thresholds are defined by the active validation profile. Scene Cut provides two ready-to-use profiles — ATAA Cinema and Netflix — and lets you customize each value in the project preferences.
The active profile is always visible in the toolbar. Click on it to switch between profiles or adjust the settings.