Convert MPEG to MTS — Free Online Tool
Convert MPEG files (MPEG-1/MPEG-2 video with MP2 audio) to MTS, the AVCHD transport stream format used by Sony and Panasonic camcorders, by re-encoding the video to H.264 and audio to AAC. This brings legacy broadcast or DVD-compatible MPEG content into the modern H.264 ecosystem while retaining the MPEG-2 Transport Stream container structure that MTS is built on.
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FFmpeg Command
Copy this command to run the same conversion locally with FFmpeg on your desktop. Download FFmpeg
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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
MPEG files typically carry MPEG-1 or MPEG-2 video alongside MP2 audio in a program stream container — a format designed for storage and broadcast in the pre-HD era. MTS uses an entirely different codec stack: H.264 (libx264) video inside an MPEG-2 Transport Stream container, with AAC audio replacing the legacy MP2 track. Because the video codecs are incompatible, the video must be fully re-encoded from MPEG-2 to H.264 using the CRF quality model, which is a computationally intensive step. The audio is similarly transcoded from MP2 to AAC. The resulting MTS file is structurally identical to footage shot on an AVCHD camcorder, making it importable into editing software like Premiere Pro, Final Cut Pro, and DaVinci Resolve that natively understands the AVCHD/MTS format.
What Each Flag Does
| Flag | What it does |
|---|---|
ffmpeg
|
Invokes the FFmpeg binary — the open-source multimedia processing engine that powers this conversion entirely within your browser via WebAssembly (FFmpeg.wasm). No data leaves your device. |
-i input.mpeg
|
Specifies the input MPEG file, which may contain MPEG-1 or MPEG-2 video and MP2 audio in a program stream container. FFmpeg auto-detects the specific MPEG variant and codec in use. |
-c:v libx264
|
Re-encodes the MPEG-1 or MPEG-2 video stream to H.264 using the libx264 encoder — the codec required by the AVCHD/MTS specification and expected by camcorder-oriented editing software like Premiere Pro and Final Cut Pro. |
-c:a aac
|
Transcodes the MP2 audio track (standard in MPEG files) to AAC, the audio codec used in AVCHD/MTS recordings. AAC provides better audio quality than MP2 at equivalent or lower bitrates. |
-crf 23
|
Sets the Constant Rate Factor for the H.264 encoder to 23, the default quality level. This controls the perceptual quality of the re-encoded video — lower values (e.g., 18) produce higher quality larger files, while values above 28 produce smaller files with more visible compression artifacts in the converted footage. |
-b:a 128k
|
Sets the AAC audio output bitrate to 128 kbps. This is sufficient for most speech and moderate-quality audio from MPEG sources; raise to 192k or 320k if your source MPEG contained high-quality stereo audio worth preserving more faithfully. |
output.mts
|
The output filename with the .mts extension, which signals to FFmpeg to use the MPEG-2 Transport Stream container — the same container format used by AVCHD camcorders from Sony and Panasonic. The extension also ensures compatibility with software that identifies MTS files by extension. |
Common Use Cases
- Importing archived MPEG broadcast recordings or DVD rips into an AVCHD-based video editing workflow that expects MTS files from camcorder media cards
- Modernizing legacy MPEG-1 or MPEG-2 video from old capture cards or VHS digitization projects into the far more efficient H.264 codec, significantly reducing file size at comparable visual quality
- Preparing MPEG footage for playback on Sony or Panasonic cameras and camcorders that support MTS/AVCHD playback from SD cards
- Combining archival MPEG content with MTS footage shot on a modern camcorder so both clips share the same codec and container for consistent editing timelines
- Converting MPEG recordings from older DVRs or set-top boxes into MTS for long-term archival storage with better compression efficiency than MPEG-2
- Re-encoding MPEG-format video files to deliver H.264 inside a transport stream for broadcast or streaming infrastructure that consumes MPEG-TS compatible files
Frequently Asked Questions
Yes, this conversion involves a generation loss because both the video and audio must be fully re-encoded — there is no way to copy the MPEG-2 or MP2 streams directly into an MTS container without transcoding. The default CRF value of 23 for H.264 produces good visual quality for most content, but CRF values of 18 or lower will preserve more detail at the cost of larger file sizes. If your source MPEG is already heavily compressed, the re-encode will not recover lost quality, so using a conservative (lower) CRF is advisable for archival purposes.
H.264 (used in MTS) is dramatically more efficient than MPEG-1 or MPEG-2 video compression — H.264 typically achieves the same visual quality at roughly half the bitrate of MPEG-2 and a quarter the bitrate of MPEG-1. Additionally, AAC audio is more efficient than the MP2 audio tracks common in MPEG files. So even at CRF 23, the output MTS file is often noticeably smaller than the source MPEG despite representing the content at equivalent or better perceptual quality.
Yes. Both Adobe Premiere Pro and Final Cut Pro have native AVCHD/MTS support and will read MTS files produced by this conversion directly. Since the file uses H.264 video and AAC audio inside a proper MPEG-2 Transport Stream container — exactly what AVCHD specifies — it is treated as native camcorder footage. Final Cut Pro may copy it into an Event library on import, which is standard behavior for AVCHD media.
MPEG program stream files carry very limited metadata compared to modern containers, and MTS is also sparse in this regard — it is primarily designed to carry video and audio timecode rather than descriptive metadata like title, author, or creation date. The conversion will preserve basic stream timing and duration information, but any extended metadata embedded in the source MPEG (such as EXIF or ID3 tags in unusual cases) will not carry over. If metadata preservation is critical, note this limitation before converting.
The video quality is controlled by the -crf flag, which accepts values from 0 (lossless) to 51 (lowest quality) for H.264. The default of 23 is a balanced midpoint. To improve quality for archival MPEG footage, lower the CRF — for example, replace '-crf 23' with '-crf 18' for near-transparent quality. To reduce file size aggressively (for streaming or sharing), raise it toward 28-30. Separately, audio bitrate is set by -b:a; changing '128k' to '192k' or '320k' will improve audio fidelity from the transcoded MP2 source.
Yes. On Linux or macOS, you can use a shell loop: 'for f in *.mpeg; do ffmpeg -i "$f" -c:v libx264 -c:a aac -crf 23 -b:a 128k "${f%.mpeg}.mts"; done'. On Windows Command Prompt, use: 'for %f in (*.mpeg) do ffmpeg -i "%f" -c:v libx264 -c:a aac -crf 23 -b:a 128k "%~nf.mts"'. This is especially useful when converting large batches of archival MPEG recordings, and since MPEG-to-H.264 re-encoding is CPU-intensive, consider adding '-preset fast' to the command to speed up processing at a slight quality tradeoff.
Technical Notes
MPEG program streams (.mpeg, .mpg) were designed around the constraints of CD-ROM storage and early broadcast infrastructure, typically carrying MPEG-1 video at up to 1.5 Mbps or MPEG-2 video at 2-15 Mbps alongside MP2 audio. MTS is the file extension for AVCHD streams, which use an MPEG-2 Transport Stream (M2TS) container — so both formats share MPEG lineage at the container level, but the codec inside MTS is H.264, which is fundamentally incompatible with MPEG-2 at the bitstream level, making full re-encoding mandatory. The H.264 encoder (libx264) used here supports the CRF quality scale rather than the fixed quantizer scale (-q:v) used by MPEG-2, so quality behaves differently: lower CRF numbers mean better quality and larger files, while higher numbers compress more aggressively. MTS supports multiple audio tracks, which means if your MPEG source had multiple audio streams (rare but possible in broadcast captures), only the first audio track will be transcoded by default — use '-map 0:a' to map all audio streams if needed. Subtitles are not supported in either MPEG program streams or MTS containers for this conversion path. One notable limitation: some MTS-aware devices and software validate the AVCHD structure (requiring specific folder hierarchy like AVCHD/BDMV/STREAM/) rather than accepting bare .mts files; this tool produces a standalone MTS file, which works in software but may not be recognized by camcorders expecting a full AVCHD directory structure.