Your files stay on your Mac.
AVCHD MTS files embed a full audio track inside camcorder footage. Convertessa pulls that track out and encodes it to Ogg Vorbis — an open, royalty-free format supported by browsers and media players everywhere. Everything runs locally on your Mac; your footage never leaves the machine.
Drag one file or an entire folder of MTS clips onto Convertessa. The app queues them all for conversion in one pass.
Choose Ogg Vorbis from the output list. Set quality to control the trade-off between file size and audio fidelity.
Click Convert. Convertessa extracts and encodes the audio track from each MTS file and writes the Ogg Vorbis output alongside the originals.
Images, audio, video, documents, archives and eBooks — all converted natively, right on your Mac.
Pick a format you have — see everything Convertessa can turn it into.
Convert hundreds of files at once with per-type group defaults and individual overrides.
First-class support for HEIC, AVIF and WebP — encode and decode, both ways. Read JPEG XL and a dozen more modern formats too.
Drop files anywhere on the window. Native, instant, and exactly what you’d expect on a Mac.
Dial in compression, resolution and bitrate. Keep originals pristine or shrink for sharing.
Never overwrite a file by accident. Convertessa appends safe suffixes automatically.
Every job is logged locally. Re-run a previous conversion or revisit recent outputs in a click.
Bundle your converted files straight into a single ZIP, TAR or 7z — packaged and ready to share the moment a job finishes.
Right-click any file in Finder and choose Convert. A Quick Action handles it on the spot — no need to open the app first.
Shrink Convertessa to a tidy mini window that tucks into a corner — just a drop zone and a format picker for quick, one-off conversions.
No cloud. No account. No upload. Every conversion happens entirely on-device, using the power already in your Mac. What you convert is nobody’s business but yours.
Script conversions, wire them into your build, or batch a folder from the terminal. The same engine, no GUI required.
Read the full CLI documentation →Shrink Convertessa down to a small, focused window — drop, convert, done, with your recent conversions one click away.
macOS 14+ · Apple Silicon & Intel
New formats, new features, and fixes — every release, on the record.
Ogg Vorbis is a pure audio format, so Convertessa extracts the audio track from your MTS file and discards the video stream. If you need the video preserved, choose a video output format instead.
Yes. Drop the folder (or pass a glob on the command line) and Convertessa converts every MTS file inside in a single batch — no need to queue files one by one.
Metadata stripping applies to image and document conversions only. Ogg Vorbis output retains any embedded tags carried over from the source file.