M2TS to OPUS Converter

Extract Opus Audio from M2TS

An .m2ts file is a BDAV MPEG-2 transport stream — the container Blu-ray discs and AVCHD camcorders record into — and the soundtrack inside it is normally Dolby AC-3 or uncompressed linear PCM, with DTS also possible on Blu-ray. This tool decodes that track and re-encodes it as Opus, the royalty-free codec the IETF standardised as RFC 6716, delivered in the Ogg encapsulation defined by RFC 7845 that gives the format its .opus extension. The picture is discarded; you get the audio on its own, typically a fraction of the size of the source clip.

How to Convert M2TS to Opus

1. Upload Your M2TS File: Drag the .m2ts onto the page or click "+ Add Files". Imports from Blu-ray or camcorder software often appear as numbered streams such as 00001.m2ts inside a BDMV/STREAM folder — those are the files to select. Several clips can be queued with one set of settings.
2. Pick a Quality Preset or Bitrate: Under File Compression, Quality Preset runs from Highest down to Lowest with "Very High (Recommended)" flagged as the sensible middle. Switch to Constant Bitrate for a fixed rate from the 8 kbps–384 kbps list, Custom Bitrate to type your own, or Specific file size to aim at an exact output size.
3. Set Audio Channel, Sample Rate, or Trim: Audio Channel offers Original, Mono, or Stereo — Original keeps a 5.1 mix intact, Mono roughly halves a dialogue-only file. Leave Audio Sample Rate on Original for Opus (see the note below on 44.1 kHz), and use Trim → Time Range to export a start time plus duration instead of the whole recording.
4. Convert and Download: Click Convert and save the .opus file. Files upload over an encrypted connection, are processed on our servers, and are deleted automatically after a few hours. No sign-up, no watermark.

What Reaches the Opus File

Sample Rate, Bitrate, and Where Opus Behaves Differently

Opus is not a general-purpose resampler target — the codec operates natively at 48 kHz, and the Audio Sample Rate dropdown here is shared across every audio format we output. The rates the Opus encoder accepts are 8000, 12000, 16000, 24000, and 48000 Hz. Leave Audio Sample Rate on Original, or choose 48000 HZ; picking 44100 HZ asks the encoder for a rate it does not support. AVCHD audio is 48 kHz and Blu-ray tracks are 48 kHz or higher, so Original is the right answer almost every time.

Bitrate behaves differently from MP3 too. Opus was designed to stay usable across an unusually wide range, and the project's own published listening tests compare it against other codecs at 64 kb/s and 96 kb/s rather than at the 256–320 kbps people habitually pick for MP3 — while cautioning against reading exact values off a quality curve. The practical reading is that you can be less generous with Opus than with MP3. A 5.1 source still needs proportionally more than a stereo one, because the rate is shared across channels.

Frequently Asked Questions

Does this keep the video, or only the audio?

Only the audio. The converter decodes the M2TS, discards the H.264 picture, and writes the soundtrack as a standalone .opus file. If you wanted the video in a modern container, M2TS to MP4 keeps both streams together; if you wanted a shorter piece of the video, trim it first with our video cutter and extract audio from the result.

Will Opus sound better than the AC-3 track already in my M2TS?

No — nothing can add back what the camcorder's AC-3 encoder already discarded. What Opus does well is carry that same audio at a much lower bitrate than a straight AC-3 copy would need. Treat the goal as "keep what is there while getting a smaller, web-friendly file", and stay at a high preset if the file will be edited or re-encoded again later.

Can the Opus file keep my 5.1 or 7.1 surround mix?

Yes. Opus supports multichannel audio, and with Audio Channel left on Original the source layout is carried through rather than folded down. Give a surround mix more bitrate than you would a stereo one, since the same rate is shared across every channel. Choose Stereo explicitly if you actually want a two-channel downmix for headphones or a web player.

Why should I avoid picking 44100 Hz for an Opus output?

Because the Opus encoder does not accept 44.1 kHz. The codec runs natively at 48 kHz and its encoder takes 8, 12, 16, 24, or 48 kHz input; the shared Audio Sample Rate dropdown on this page lists 44100 HZ because other output formats use it. AVCHD audio is 48 kHz to begin with, so Original is both the safest and the most faithful choice here.

Will the .opus file play on my phone, car stereo, or smart TV?

In browsers, almost certainly — Opus reaches roughly 96% of tracked users, with support in Chrome 33+, Edge 14+, Firefox 15+, and Opera 20+; Safari's support is partial on macOS and complete on iOS from Safari 18.4. Standalone hardware is patchier: many car head units and older TVs never added Opus. When the target is a device rather than a browser, M2TS to MP3 is the safer choice, and M2TS to AAC suits the Apple ecosystem.

What exactly is a .opus file — is it an Ogg file?

Yes. Opus is a codec, not a container, so it has to be wrapped in something. The IETF specified Ogg encapsulation for Opus in RFC 7845, and that combination — Opus inside Ogg, named .opus — is what this converter writes and what browsers expect. The same codec can also live inside WebM and MP4, which is why a WebM video's soundtrack is often Opus too.

My M2TS has more than one audio track. Which one do I get?

The first audio track the decoder finds. Multi-track material — a director's commentary, a second language, a separate mic feed on a professional recording — cannot be selected from this page. If you need a specific track, demux it in a desktop tool such as MKVToolNix or tsMuxeR first, then convert the extracted track here.

Why did my conversion fail on a Blu-ray file?

Almost always AACS encryption. Retail Blu-ray discs are protected, sometimes with BD+ as well, and a protected stream cannot be decoded by any converter. Unprotected material converts normally: camcorder recordings, your own renders, and files you have already decrypted legally. A truncated or partially-copied .m2ts will also fail, because the transport stream ends mid-packet.

Is .m2ts the same as .mts, and how are my files handled?

They are the same BDAV transport stream — .MTS is what a camcorder writes under AVCHD's 8.3 filename rules, .m2ts is the Blu-ray and desktop spelling — so either converts identically here. Whichever you upload travels over an encrypted connection, is processed on our servers, and is deleted automatically after a few hours. Nothing is shared or made public, and no account is required.