SubFT

Embed saved subtitles in media

Add or replace a subtitle stream, check original and backup destinations, and verify the rewritten media.

Free workspaceNo credits required

Before you start

Save the subtitle text first. Connect supported original media, grant browser write access and leave space for a backup and temporary processing. Importing a container does not guarantee that FFmpeg can rewrite it. If writable handles are unavailable, download the subtitles instead.

Embed the subtitles in the media file

  1. Choose embedding and stream behavior

    Open the subtitle export and select Embed in media. Adding a stream is the default. Choose replacement only for the intended checked physical subtitle stream; inspect the destination carefully before accepting replacement.

  2. Provide the required backup access

    In a directory project, embedding creates <media>.bak beside the original. An existing .bak blocks another rewrite: inspect the backup and original before resolving it manually. In a file project, grant write access to the original and choose a separate backup destination when prompted. Check both destinations before continuing.

  3. Run and verify the rewrite

    Select Embed and keep the view open. Selected operation results for one media file are combined in one FFmpeg pass; media files are processed in turn. If an error is caught, SubFT attempts to restore the backup. Verified success removes a directory project’s temporary backup; a file project’s separately chosen backup remains. If restoration fails, keep the backup for manual recovery.

  4. Result

    The verified media contains the intended subtitle stream. The saved text remains available independently.

The export panel with Embed in media selected, the embedded subtitle stream choice and a note that a backup is created before writingThe export panel with Embed in media selected, the embedded subtitle stream choice and a note that a backup is created before writing
Review stream replacement and backup requirements before embedding

Check the result

Reopen the media in a player, select the subtitle stream and inspect representative cues. Confirm other streams still work. If registration alone failed after verified writing, retry registration instead of repeating the rewrite.

If something goes wrong

Keep the saved subtitle document if export fails. Read the destination’s error and restore its file access or permissions before trying again. A new AI operation cannot repair an output path or write permission. Follow export recovery.