Convert M2TS to AIFC — Free Online Tool
Extract and convert audio from M2TS Blu-ray or AVCHD files into AIFC format using PCM big-endian encoding. This tool strips the video stream entirely and outputs a lossless-quality AIFC file suitable for professional audio workflows on macOS and legacy Apple systems.
to
FFmpeg Command
Copy this command to run the same conversion locally with FFmpeg on your desktop. Download FFmpeg
Drop your M2TS file here
or click to browse
Free — no uploads, no signups. Your files never leave your browser.
Settings
Note: Browser-based encoding uses approximate quality targets. For precise CRF compression, copy the FFmpeg command above and run it on your desktop.
Estimated output:
Conversion Complete!
DownloadHow It Works
M2TS files are MPEG-2 Transport Stream containers typically carrying H.264 or H.265 video alongside multi-channel audio encoded as AAC, AC-3, or DTS. During this conversion, FFmpeg discards the video stream entirely and extracts only the primary audio track, re-encoding it to PCM signed 16-bit big-endian (pcm_s16be) — the native codec for AIFC. Because M2TS audio is usually compressed (lossy), the output is not a true lossless capture of the original source, but the PCM encoding in AIFC introduces no additional generation loss beyond what existed in the M2TS audio. The result is an uncompressed or minimally compressed AIFC file with big-endian byte ordering, as defined by Apple's AIFF-C specification.
What Each Flag Does
| Flag | What it does |
|---|---|
ffmpeg
|
Invokes the FFmpeg tool, which handles demuxing the M2TS transport stream, decoding the compressed audio inside it, and re-encoding to PCM for the AIFC output. |
-i input.m2ts
|
Specifies the input M2TS file — a Blu-ray or AVCHD container that FFmpeg will demux to access its video, audio, and subtitle streams separately. |
-c:a pcm_s16be
|
Sets the audio codec to signed 16-bit big-endian PCM, which is the native encoding for AIFC files. This decodes whatever compressed audio format exists in the M2TS (such as AAC or AC-3) and writes it as uncompressed PCM with big-endian byte ordering required by the AIFF-C specification. |
-b:a 128k
|
Specifies a target audio bitrate of 128 kbps, though this flag is effectively inert for PCM codecs like pcm_s16be — uncompressed PCM output size is determined by sample rate and bit depth, not a bitrate target. It is included by the tool's defaults but does not alter the AIFC output. |
output.aifc
|
Defines the output filename and triggers FFmpeg to use the AIFC muxer. The .aifc extension is essential — it tells FFmpeg to write an AIFF-C container with the FORM/AIFC chunk structure, as distinct from a plain .aiff file. |
Common Use Cases
- Extracting the audio commentary or dialogue track from a Blu-ray rip to edit in Logic Pro or Final Cut Pro on macOS, where AIFC is a natively supported professional format
- Archiving the audio portion of AVCHD camcorder footage (.m2ts files) into AIFC for long-term storage in a format compatible with Apple-based post-production pipelines
- Preparing audio from a Blu-ray concert or live performance recording for mastering in a DAW that accepts AIFC as a lossless interchange format
- Converting M2TS broadcast captures to AIFC for use with legacy Mac audio software or hardware samplers that require big-endian PCM in AIFF-C containers
- Stripping video from AVCHD interview footage to produce a clean AIFC audio file for transcription or podcast post-processing on macOS
Frequently Asked Questions
It depends on what audio codec is in your M2TS file. Most M2TS files from Blu-ray or AVCHD camcorders contain lossy audio — typically AAC, AC-3 (Dolby Digital), or DTS. Converting this to PCM in AIFC does not add any further lossy compression, but it cannot recover quality that was already lost during the original encoding. If your M2TS source happened to carry lossless audio (like Dolby TrueHD or DTS-HD MA), the conversion to 16-bit PCM may reduce dynamic range compared to a 24-bit lossless representation.
The default codec selected is pcm_s16be (signed 16-bit big-endian PCM), which is the baseline standard for AIFC and provides CD-quality audio at 44.1 or 48 kHz. If your M2TS source contains high-resolution audio (e.g., from a Blu-ray with 24-bit lossless tracks) and you want to preserve that bit depth, you can manually change the command to use -c:a pcm_s24be instead, which AIFC also supports natively and is commonly used in professional audio contexts.
No. AIFC does not support multiple audio tracks within a single file, so only the first (default) audio track from the M2TS is extracted. If your M2TS contains multiple tracks — such as a main feature mix and a director's commentary — you would need to run separate FFmpeg commands using the -map flag to select each track individually, producing one AIFC file per track.
Both are discarded entirely. AIFC is a pure audio container and has no provision for subtitle data or chapter metadata. If you need to preserve subtitles or chapter timing from the original M2TS, you would need to extract them separately using a different tool or FFmpeg command targeting subtitle stream output formats like SRT or WebVTT.
Because the output uses PCM encoding (pcm_s16be), the -b:a 128k bitrate flag has no practical effect — PCM audio in AIFC is uncompressed and its size is determined entirely by sample rate, bit depth, and duration, not a target bitrate. To change audio quality meaningfully, switch the codec with -c:a pcm_s24be for higher bit depth, or specify a sample rate with -ar 48000 to match the source M2TS sample rate. For example: ffmpeg -i input.m2ts -c:a pcm_s24be -ar 48000 output.aifc
Yes. On Linux or macOS you can use a shell loop: for f in *.m2ts; do ffmpeg -i "$f" -c:a pcm_s16be "${f%.m2ts}.aifc"; done. On Windows Command Prompt, use: for %f in (*.m2ts) do ffmpeg -i "%f" -c:a pcm_s16be "%~nf.aifc". This is especially useful when extracting audio from a large library of AVCHD camcorder clips, which are often stored as dozens of individual .m2ts segment files.
Technical Notes
M2TS uses MPEG-2 Transport Stream framing with a fixed 192-byte packet structure (including a 4-byte timestamp header on top of the standard 188-byte TS packet), which FFmpeg demuxes transparently. The audio streams inside M2TS can vary significantly: AVCHD camcorders typically write AC-3 or AAC stereo, while Blu-ray discs may carry multi-channel AC-3, DTS, Dolby TrueHD, or DTS-HD MA. FFmpeg will decode whichever primary audio stream it finds and re-encode it to pcm_s16be for the AIFC output. AIFC uses big-endian byte ordering for its PCM data, in contrast to WAV which uses little-endian — this matters when integrating with systems that read raw PCM data directly. The output file will have the .aifc extension and the FORM/AIFC chunk structure defined by Apple. Note that AIFC is sometimes confused with AIFF; while both use the FORM container, AIFC explicitly signals the compression type in its COMM chunk (even for uncompressed PCM, it uses the 'NONE' compression type identifier rather than defaulting to AIFF's implicit PCM). File sizes will be substantially larger than the M2TS source audio because PCM is uncompressed: a 90-minute stereo 48 kHz 16-bit track will produce approximately 950 MB of AIFC output regardless of the original M2TS audio bitrate.