Merge two subtitle files into one
Drop both files. Two languages are matched line by line by time and shown together; two parts of a film are joined, with part 2 moved to start where part 1 ends.
Two languages at once
Most players show one subtitle track at a time, so learning a language with a film usually means switching back and forth. A merged file shows both: the first language, and the second under it in yellow or in italics. Saved as ASS, the second language moves to the top of the picture instead.
Lines are matched by time, not by number — translators split and join lines their own way, and a translation of 900 lines rarely meets an original of 1,100 by counting. A line of the second language goes with the line it is spoken over; one spanning two lines of the first shows under both.
When the two come from different releases
A translation downloaded separately is often timed for another release — a longer intro, or a 25 fps TV version. The two then barely meet, and the page finds the shift and the frame rate that line them up, says which file was adjusted to which, and how to do it the other way round if your video matches the other one.
Part 1 and part 2
Old releases split a film across two discs, and their subtitles come as CD1 and CD2, each starting from zero. Joined, part 2 must start where part 1 of the video ends — which the subtitle file does not know, so you enter it from your player. If part 2 already carries on the timing of part 1, the page notices and moves nothing.
Questions
- Can I add a third language?
- Yes — merge the result with one more file. The third language gets its own colour, light blue.
- Both languages are inside my MKV.
- Open the MKV itself: every subtitle track inside appears in the file list as if it were a separate file, and any two of them merge the same way.
- Which file goes first?
- The one on screen when you press Merge: it goes first and keeps its timing. To swap, pick the other file in the file list before merging.
- The two languages still do not line up.
- Then the releases differ by more than a shift or a frame rate — a cut scene, a different edit. Undo, sync one file to the video by two lines, then merge again.