Your files stay on your Mac.
Convertessa reads the audio track embedded in your AVCHD MTS clips and writes it out as AIFF, an uncompressed lossless format. No network connection is required; every file stays on your Mac from start to finish. Drag a single clip or a whole camera-card folder and Convertessa queues everything at once.
Drag one clip or an entire AVCHD folder onto Convertessa. It finds every MTS file in the tree and queues them all for conversion.
Pick AIFF from the output format list. Because AIFF is a lossless format there is no quality setting to configure.
Click Convert. Convertessa extracts the audio track from each MTS file and writes a matching AIFF file alongside the original.
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.
Yes. Convertessa passes through all audio channels present in the MTS stream — stereo or multi-channel — to the AIFF output without downmixing.
Yes. Drop the root folder of an AVCHD card onto Convertessa and it locates every MTS file in the folder tree, converting them all in a single run. You can also use the CLI: convertessa /Volumes/AVCHD --to aiff.
Yes. Convertessa removes embedded metadata from the source MTS files during conversion, so the resulting AIFF files do not carry over camera-specific tags from the original clip.