Trim MTS — Free Online Tool
Trim MTS camcorder footage to a specific clip without re-encoding, preserving the original H.264 video and AC-3/AAC audio streams intact. Ideal for cutting down AVCHD recordings from Sony or Panasonic camcorders directly in your browser — no quality loss, no upload required.
to
FFmpeg Command
Copy this command to run the same conversion locally with FFmpeg on your desktop. Download FFmpeg
Drop your MTS file here
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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
Because the input and output are both MTS (AVCHD), this tool uses stream copying (`-c copy`) rather than re-encoding. FFmpeg reads the MPEG-2 Transport Stream container, seeks to the specified start point, and copies the H.264 video and AC-3 or AAC audio packets directly into a new MTS file up to the specified end point. No transcoding occurs, so there is no generation loss and processing is extremely fast. The only caveat is that the actual cut points are snapped to the nearest keyframe (I-frame) in the H.264 stream, which means the trim may be a fraction of a second off from the exact timestamps you specify — a normal behavior when stream copying any H.264 container.
What Each Flag Does
| Flag | What it does |
|---|---|
ffmpeg
|
Invokes the FFmpeg binary — the open-source multimedia processing engine that powers this tool via its WebAssembly (FFmpeg.wasm) build running entirely in your browser. |
-i input.mts
|
Specifies the input MTS file — an AVCHD MPEG-2 Transport Stream as recorded by Sony or Panasonic camcorders, containing H.264 video and AC-3 or AAC audio. |
-ss 00:00:00
|
Sets the trim start time to the beginning of the file (0 seconds). Change this timestamp to seek to any point in the MTS recording; FFmpeg will snap to the nearest preceding H.264 keyframe when stream copying. |
-to 00:00:10
|
Sets the absolute end time of the output clip to 10 seconds. FFmpeg stops copying the AVCHD stream at this point, producing a trimmed MTS file of approximately 10 seconds in duration. |
-c copy
|
Instructs FFmpeg to copy all streams — H.264 video, AAC/AC-3 audio, and any subtitles — directly from the input MTS to the output MTS without re-encoding. This preserves original quality and makes the trim operation nearly instantaneous regardless of file size. |
output.mts
|
The filename of the resulting trimmed AVCHD clip. The MTS extension ensures the output retains the MPEG-2 Transport Stream container format, compatible with video editors and media players that support AVCHD footage. |
Common Use Cases
- Extract a specific scene from a Sony Handycam or Panasonic HC-series recording to share without re-encoding the footage
- Remove the camera-on and camera-off dead footage at the beginning and end of an AVCHD clip before importing into a video editor
- Create a short highlight clip from a longer MTS event recording (wedding, concert, sports) to send to clients for review
- Trim a long AVCHD recording into multiple shorter segments to stay within file size or duration limits when archiving to disc or cloud storage
- Isolate a problematic segment of an MTS file for troubleshooting playback or compatibility issues before editing the full project
- Cut a quick preview clip from raw camcorder footage to check exposure, focus, or audio quality before committing to a full editing workflow
Frequently Asked Questions
No. Because both the input and output are MTS, this tool uses `-c copy` to stream-copy the H.264 video and AAC/AC-3 audio directly — no re-encoding takes place. The video quality of the output is bit-for-bit identical to the original. The only minor imprecision is that cut points are aligned to the nearest H.264 keyframe, which may shift the trim by up to a second depending on the camcorder's keyframe interval.
This is expected behavior when stream-copying H.264 video. FFmpeg cannot cut mid-GOP (Group of Pictures) without re-encoding, so it snaps the start point to the nearest preceding keyframe (I-frame). AVCHD camcorders typically insert a keyframe every 0.5–2 seconds, so the actual cut may differ from your requested time by that amount. If frame-accurate trimming is critical, you would need to re-encode the output by removing the `-c copy` flag and specifying video and audio codecs instead.
Yes. The `-c copy` flag copies all streams from the MPEG-2 Transport Stream, including multiple audio tracks and subtitle streams if present in the original AVCHD file. The container structure and stream mappings are preserved. However, MTS does not support chapter markers, so no chapter data will be present in the output regardless.
Possibly, but camcorder playback from a memory card relies on a proprietary directory structure (AVCHD folder hierarchy with BDMV and CERTIFICATE folders) and an index database file. A standalone trimmed MTS file created by FFmpeg will play in most desktop media players and video editors, but re-importing it into the camcorder's memory card for on-device playback typically requires rebuilding that folder structure, which is outside the scope of this tool.
Modify the values after `-ss` (start time) and `-to` (end time) in the command. Both accept the format `HH:MM:SS` or `HH:MM:SS.mmm` for millisecond precision — for example, `-ss 00:01:30 -to 00:03:45` trims from 1 minute 30 seconds to 3 minutes 45 seconds. You can also use `-ss 00:01:30 -t 00:02:15` if you prefer to specify a duration rather than an end timestamp; `-t` sets the length of the output clip rather than the absolute end time.
Yes. On Linux or macOS you can wrap the command in a shell loop: `for f in *.mts; do ffmpeg -i "$f" -ss 00:00:00 -to 00:00:10 -c copy "trimmed_$f"; done`. On Windows Command Prompt, use `for %f in (*.mts) do ffmpeg -i "%f" -ss 00:00:00 -to 00:00:10 -c copy "trimmed_%f"`. This is especially useful for processing large batches of AVCHD clips from a camcorder dump, and since `-c copy` is used, the operation is very fast even for large files.
Technical Notes
MTS files are MPEG-2 Transport Stream containers carrying AVCHD content — specifically H.264 (AVC) video and AC-3 or AAC audio, as defined by the AVCHD specification used in Sony and Panasonic camcorders. Because this trim operation uses `-c copy`, the H.264 Baseline/Main/High profile and level from the original recording are preserved exactly, including any camera-specific SEI metadata embedded in the stream. The MPEG-2 TS container uses a fixed 188-byte packet structure, and FFmpeg handles packet-level copying cleanly for this format. One known limitation with transport streams is that PTS (Presentation Timestamp) discontinuities can occasionally occur at the trim boundary, which some players may handle differently — if you encounter playback issues at the start of the clip, adding `-avoid_negative_ts make_zero` to the command can help normalize timestamps. Audio stream selection defaults to the first detected track; if your camcorder recorded dual-channel or multi-language audio, all tracks are preserved with `-c copy` unless you explicitly map streams with `-map`. Files larger than 1GB are best processed using the FFmpeg command locally on your desktop, as browser memory constraints may apply.