Convert MTS to captions

Sonix transcribes your MTS file and creates closed captions that make your content accessible to everyone.

Free to start — no credit card required.See pricing

ADA compliant
5-min turnaround
Accessible
MTS conversion guide

Create captions from MTS in 6 steps

  1. 1
    Create account~30 sec

    Sign up for a free Sonix trial with 30 free minutes.

  2. 2
    Upload file~1 min

    Upload your MTS file from your computer or cloud storage.

    44+ formats supported
  3. 3
    Select language~10 sec

    Select the language spoken in your file.

    54+ languages
  4. 4
    Auto-transcribe~5 min

    Sonix AI transcribes your MTS with word-level timestamps.

  5. 5
    Edit captions~2 min

    Fine-tune timing and formatting for accessibility.

  6. 6
    Export~10 sec

    Download your closed captions as SRT or VTT files.

    30+ export formats
The MTS file format

Understanding MTS files

What is a MTS file?

HD camcorder video format (AVCHD)

MTS files are also Advanced Video Codec High Definition (AVCHD) video files that contain high definition MPEG videos that have been captured by certain models of video camcorders. Originally designed by Sony and Panasonic for their High Definition camcorders, JVC, Sanyo, and Canon camcorders also now record audio and video in the MTS file format. Typically MTS videos have high definition streams and support both 720p and 1080i HD videos.

Common uses for MTS files

  • HD camcorder recordings
  • Consumer video production
  • Event videography
  • Sony camcorders
  • Panasonic camcorders
  • Canon camcorders
  • JVC camcorders

Who works with MTS files?

Documentary filmmakers, local news crews, and families digitizing home videos often have large archives of MTS footage from AVCHD camcorders that were common between roughly 2008 and 2015. Video editors also encounter MTS files when ingesting camcorder SD cards into tools like Adobe Premiere Pro or Final Cut Pro, where the files sit inside the AVCHD folder structure.

MTS vs MP4: which should you use?

MTS wraps H.264 video in an MPEG-2 transport stream, a structure designed for in-camera recording and broadcast-style error resilience, while MP4 uses the MPEG-4 Part 14 container with much broader software and device support. Because both formats commonly carry H.264 video, MTS footage can often be remuxed to MP4 without re-encoding or quality loss. MTS is what you get straight off an AVCHD camcorder; MP4 is the better choice for editing, sharing, and playback on modern devices.

Convert MP4 to text
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Get your MTS captions in minutes
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Accuracy rate
Industry-leading AI for MTS files
53+
Languages
Captions in any language
30+
Export formats
SRT, VTT, and TTML
MTS conversion FAQ

MTS captions: frequently asked questions

Can you create closed captions from MTS files?

Yes! Sonix transcribes your MTS file with precise timestamps and creates closed captions in standard formats.

What's the difference between subtitles and closed captions?

Closed captions include non-speech elements like [music], [applause], and speaker identification. They're designed for deaf and hard-of-hearing viewers.

Are Sonix captions ADA compliant?

Yes! Sonix captions meet accessibility requirements when properly reviewed and edited. Our editor helps ensure timing and accuracy standards.

What caption formats are supported?

Export captions as SRT, VTT, or TTML. Each format has specific use cases.

Can I add sound descriptions?

Yes! Use our editor to add [music], [laughter], and other non-speech descriptions for full accessibility.

Do captions help with SEO?

Absolutely! Captions make your video content searchable and improve accessibility, both of which can boost SEO rankings.

Why won't my MTS file play on my computer?

MTS files use the AVCHD transport-stream structure, which some default media players do not support, and clips copied out of the camcorder's AVCHD folder can lose playback context. Opening the file in VLC or remuxing it to MP4 usually resolves the issue.

Do I need to convert MTS to MP4 before transcribing?

No. You can upload the MTS file directly, and its audio track is extracted and transcribed the same way as an MP4 upload.

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