Convert 3GP to M2TS — Free Online Tool
Convert 3GP mobile video files to M2TS (Blu-ray AVCHD) format using H.264 video and AAC audio encoding entirely in your browser. This upgrade path takes compressed, low-bandwidth 3G phone footage and repackages it into a broadcast-grade MPEG-2 Transport Stream container suitable for Blu-ray authoring and HD video workflows.
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FFmpeg Command
Copy this command to run the same conversion locally with FFmpeg on your desktop. Download FFmpeg
Drop your 3GP file here
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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
3GP files store video using H.264 or MPEG-4 compression optimized for the tight bandwidth and storage constraints of 3G mobile networks, with audio typically encoded in AAC at low bitrates. During this conversion, the video stream is re-encoded using libx264 with a CRF of 23, which resamples and reframes the source to meet M2TS container requirements — including enforcing even pixel dimensions via the scale filter that was required for 3GP's codec alignment. The audio is re-encoded to AAC at 128k, doubling the typical 3GP audio bitrate to better match the higher-fidelity expectations of the M2TS format. The output is wrapped in an MPEG-2 Transport Stream container, the same packetized structure used on Blu-ray discs and AVCHD camcorders, which supports subtitle tracks and multiple audio streams even though the 3GP source carried neither.
What Each Flag Does
| Flag | What it does |
|---|---|
ffmpeg
|
Invokes the FFmpeg binary — in the browser this runs as a WebAssembly (FFmpeg.wasm) instance with no server involvement; on the desktop this calls your locally installed FFmpeg. |
-i input.3gp
|
Specifies the input 3GP file. FFmpeg reads the container to detect the video codec (typically H.264 or MPEG-4) and audio codec (typically AAC or AMR-NB) packaged inside the 3GP wrapper. |
-c:v libx264
|
Re-encodes the video stream using the libx264 H.264 encoder. Even if the 3GP source already contains H.264, a full re-encode is performed here to ensure the output conforms to the M2TS container's stream requirements and to apply the CRF quality setting. |
-c:a aac
|
Encodes the audio stream to AAC using FFmpeg's native AAC encoder. This upgrades the audio from the typically low-bitrate (32k–64k) AAC or AMR audio in the 3GP source to a 128k AAC stream suited for the higher-fidelity context of an M2TS file. |
-crf 23
|
Sets the Constant Rate Factor for libx264 to 23, the standard default quality level. Given that 3GP source footage is already heavily compressed and low resolution, this CRF provides a reasonable quality-to-filesize balance without introducing excessive re-encoding bloat. |
-b:a 128k
|
Sets the AAC audio output bitrate to 128 kilobits per second. This is double the typical 3GP audio bitrate, matching the quality baseline expected in M2TS/AVCHD workflows while avoiding inflating the file unnecessarily beyond what the source audio quality can support. |
output.m2ts
|
Specifies the output filename with the .m2ts extension. FFmpeg uses this extension to select the MPEG-2 Transport Stream muxer with the 192-byte Blu-ray packet format, which is the correct container structure for AVCHD and Blu-ray authoring workflows. |
Common Use Cases
- Archiving old 3G-era mobile phone footage into a Blu-ray-compatible format for long-term storage or disc authoring
- Importing mobile video captured on early smartphones into professional NLE timelines that prefer AVCHD or M2TS ingest
- Preparing historical 3GP news or documentary footage for broadcast playout systems that require MPEG-2 Transport Stream delivery
- Upscaling and repackaging 3GP clips for inclusion in a Blu-ray disc project alongside high-definition AVCHD camcorder footage
- Converting mobile-shot event footage (concerts, sports, family moments) into an M2TS archive that can be played back on Blu-ray players or PlayStation consoles
- Migrating a library of 3GP clips from a feature phone backup into an M2TS workflow for color grading or post-production
Frequently Asked Questions
No — the visual quality of the output is fundamentally bounded by what was captured in the original 3GP file. 3GP was designed for low-bandwidth 3G networks, so source footage is typically low resolution (often 176×144 or 320×240) and heavily compressed. Re-encoding to M2TS with libx264 at CRF 23 will produce a larger, cleaner-looking file, but it cannot recover detail that was discarded during the original mobile encoding. Think of this as a format upgrade for compatibility, not an upscale.
3GP was purpose-built for minimal file size — it uses aggressive compression and very low audio bitrates to fit within 3G network and handset storage limits. M2TS is a container designed for Blu-ray and broadcast environments where storage is not a constraint and quality is the priority. The re-encoding at CRF 23 and 128k AAC, combined with the packetized MPEG-2 Transport Stream overhead, will produce files several times larger than the 3GP source even at the same resolution.
The M2TS container format is the correct wrapper for Blu-ray, but a compliant Blu-ray disc also requires a specific directory structure (BDMV/BACKUP folders, index files, and a MovieObject) that this converter does not generate. The output file is valid AVCHD-style M2TS and will be compatible with Blu-ray authoring software like Encore or Wondershare DVD Creator, which can then wrap it into a proper disc structure. You should not simply copy the raw .m2ts file to a disc and expect it to play.
3GP files can embed metadata such as capture timestamps, GPS coordinates, and device information in their container atoms. M2TS has limited native metadata support compared to containers like MKV or MP4, and the FFmpeg command used here does not include explicit metadata mapping flags. Most 3GP-specific metadata will not be preserved in the output M2TS file. If metadata preservation is important, consider extracting it from the 3GP with a tool like ExifTool before converting.
To adjust video quality, change the -crf value: lower numbers like 18 produce higher quality and larger files, while higher numbers like 28 or 35 produce smaller files with more compression. The CRF scale runs from 0 (lossless) to 51 (worst quality). To change audio quality, replace 128k in -b:a 128k with a higher value like 192k or 256k for better fidelity. For example: ffmpeg -i input.3gp -c:v libx264 -c:a aac -crf 18 -b:a 192k output.m2ts
Yes — on Linux or macOS you can use a shell loop: for f in *.3gp; do ffmpeg -i "$f" -c:v libx264 -c:a aac -crf 23 -b:a 128k "${f%.3gp}.m2ts"; done. On Windows Command Prompt, use: for %f in (*.3gp) do ffmpeg -i "%f" -c:v libx264 -c:a aac -crf 23 -b:a 128k "%~nf.m2ts". The browser-based tool processes one file at a time, so the command-line approach is strongly recommended for bulk conversions or files larger than 1GB.
Technical Notes
The 3GP container spec requires that video frame dimensions be divisible by 2, which is why the special scaling filter (scale=trunc(iw/2)*2:trunc(ih/2)*2) is part of the 3GP format's handling — this ensures any odd-dimension source is padded to even pixels before encoding. M2TS imposes no such constraint at the container level, but libx264 still requires even dimensions, so the filter remains relevant. The M2TS container supports multiple audio tracks and subtitle streams, neither of which 3GP can carry; the output file will have a single H.264 video track and a single AAC audio track. 3GP audio is often encoded at 64k or below in the original file, so the 128k AAC output represents a quality ceiling imposed by the source — transcoding low-bitrate AAC to higher-bitrate AAC will not recover lost frequency information. If the 3GP source uses AMR-NB audio (common on very early feature phones), FFmpeg will transcode it to AAC automatically, but the speech-optimized AMR codec's narrow frequency response (300–3400 Hz) will be apparent in the output regardless of the AAC bitrate used. The MPEG-2 Transport Stream packetization in M2TS adds fixed-size 192-byte packets (with a 4-byte timestamp prefix over the standard 188-byte MPEG-TS packet), which contributes to the larger file size but also makes the format robust for streaming and broadcast playout.