Your files stay on your Mac.
AVCHD MTS files embed H.264 video inside Sony and Panasonic camcorder directory structures that most editors and media servers won't open directly. Converting to MPEG-TS puts the same footage into a standard broadcast container accepted by virtually every NLE, player, and streaming pipeline. Convertessa runs the conversion entirely on your Mac — files never leave your machine.
Drag one or more .mts files — or an entire folder of camcorder clips — onto Convertessa. Batch mode processes every file in the folder in one pass.
Choose MPEG-TS from the output format list. Set output quality to dial in the balance between file size and video fidelity before converting.
Click Convert. Convertessa processes each clip on-device and saves the .ts files alongside your originals — no upload, no internet dependency.
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.
MPEG-TS is the native container for broadcast playout, HLS streaming, and many professional NLEs. If your workflow expects a Transport Stream, .ts files slot in without transcoding at the next stage.
Yes. Drop the folder onto Convertessa or run convertessa /path/to/clips/ --to ts and every .mts file inside is converted in a single batch.
The quality setting controls the encoded video stream inside the .ts container. A higher value preserves more detail at the cost of a larger file; lower values shrink the file at some loss of fidelity.