MJPEG to MTS Converter

MJPEG to MTS: What This Tutorial Covers

.mts is the extension AVCHD camcorders put on their recordings, so it is what a lot of editing and archive workflows are set up to ingest. This tutorial converts a raw .mjpeg capture into an MPEG transport stream under that name, and is honest about the part most pages skip: what you get is a transport stream, not a camcorder disc structure, and that difference decides whether your target software accepts it.

How to Convert MJPEG to MTS

1. Upload Your MJPEG File: Drag the .mjpeg onto the page or click "+ Add Files"; several captures can queue together. Uploads travel over an encrypted connection and convert on our servers.
2. Leave the Video Codec on H.264: H.264 is preselected, which is the codec AVCHD itself uses. The list here is deliberately short — DivX, H.265, MPEG-1, MPEG-2, MPEG-4 and Xvid are the alternatives, and most of them defeat the point of choosing MTS.
3. Set File Compression, Video Resolution or Trim: File Compression starts on Quality Preset at Very High (Recommended), with Specific file size, Constant Bitrate, Variable Bitrate, Constant Quality and Constraint Quality available. Video resolution keeps the source size by default, and Trim → Time Range takes a Start time and Duration.
4. Convert and Download: Click Convert and save the .mts. No sign-up, no watermark.

Walk-through: What .mts Does and Doesn't Give You

The conversion re-encodes your frames to H.264 and multiplexes them into an MPEG transport stream — a container designed for broadcast-style delivery, where a decoder can join the stream at any point rather than needing the file header first. That is genuinely useful: unlike your raw .mjpeg, the result carries timing, plays in ordinary media players, and imports into editors that list MTS as a supported input.

What it is not is AVCHD. We checked the framing of the output: it is a standard MPEG transport stream built from 188-byte packets. Camcorder media stores its streams inside a BDMV directory alongside index and clip-information files, and that surrounding structure is part of what makes a recording AVCHD. A single file cannot reproduce it. So use this conversion when something needs to read an MTS, not when something needs to mount a camcorder volume.

The settings that matter are few, because a raw MJPEG source constrains what is knowable about the footage:

Common Errors and How to Fix Them

• "My camcorder or Blu-ray player won't see the file" — Expected. Those devices scan for a disc structure, not a loose file. Copying an .mts into a camera's folder does not make it a recognised recording; import it into editing software instead.
• "The clip plays too fast or reports the wrong length" — A raw MJPEG stores no frame rate, so decoders assume 25 fps and the duration is derived from the frame count at that rate. Footage recorded at 10 fps therefore plays two and a half times too quickly. There is no frame-rate control on this page, so correct the speed in your editor after import.
• "My editor says the file has no audio" — Correct, and unavoidable here. The source stream contains video frames only.
• "The output is much bigger than I expected" — Check Video resolution. At the original size, H.264 still has to describe every pixel of a noisy camera image; halving the resolution roughly quarters the pixel count.
• "Playback stutters or the picture breaks up part-way" — Usually damage in the source. Interrupted camera writes leave truncated frames, and some hardware encoders append stray bytes after the last restart marker. Trim to a range before the damage and convert that.
• "An app rejects .mts but accepts .mp4" — MTS support is common in editors and rare in browsers and messaging apps. Convert to MJPEG to MP4 instead; the video inside is the same H.264.

When This Doesn't Work

If your goal is to restore or replace footage on AVCHD media, this is the wrong tool — that requires authoring the whole volume structure, not producing a stream. If your goal is a file an old camcorder will play back internally, no converter can deliver it, because the device indexes its own recordings. And if the source .mjpeg is truncated, the missing frames are simply gone; conversion cannot rebuild them. Where MTS is merely a convenient interchange format for an editing workflow, though, this conversion does the job, and MTS to MP4 takes the result back out again later.

Frequently Asked Questions

Is the file I get a real AVCHD file?

It is a real MPEG transport stream with the .mts extension, which is what most software means when it says it accepts MTS. It is not an AVCHD recording in the full sense, because AVCHD also involves the BDMV directory structure and its index and clip-information files that camcorder media carries. For import into an editor, the distinction rarely matters; for anything that expects to mount camcorder media, it matters completely.

Why is there no sound in the converted file?

Because there was none to begin with. A raw MJPEG elementary stream carries video frames and nothing else, so no audio track is written. It is worth noting that AVCHD's permitted audio formats are Dolby AC-3 and uncompressed linear PCM, so even if audio were present, matching genuine AVCHD would mean choosing one of those rather than a general-purpose codec.

Which video codec should I choose for an MTS?

Keep H.264. It is the codec AVCHD is built on, so it is the one that MTS-aware software is guaranteed to decode. H.265 produces smaller files but is far less likely to be accepted by anything that specifically wants MTS, and the MPEG-1, MPEG-2, MPEG-4, Xvid and DivX options exist for compatibility with much older pipelines rather than for this workflow.

Why does the duration not match my recording?

Because the recording never stored one. Raw MJPEG has no container and therefore no duration, bitrate or frame-rate field — decoders fall back to an assumed 25 fps and the length is inferred from the frame count. A minute captured at 15 fps becomes 900 frames, which is written as a 36-second file. Every frame is present and in order; only the timebase is a guess.

Should I use MTS at all, or go straight to MP4?

Use MTS when a specific tool asks for it — some editing and broadcast ingest workflows are configured around it. For anything else, MP4 is the better container: it holds the same H.264 video, plays in browsers, phones and TVs, and is accepted by far more software. The transport stream's advantage is robustness in delivery, which matters for broadcast rather than for a file on a disk.

Can I cut the recording down before converting?

Yes. Set Trim to Time Range and enter a Start time and Duration in seconds or as HH:MM:SS.sss. Because the timebase is the assumed 25 fps described above, work from frame numbers divided by 25 rather than from real elapsed time. For repeated cuts on an already-converted file, Video Cutter handles it directly.

Will the picture look the same as my MJPEG source?

Close, with two deliberate changes. The frames are re-encoded to H.264, which adds one generation of loss on top of the JPEG compression the camera already applied, and the colour is normalised to the limited-range 4:2:0 form that players and hardware decoders expect — MJPEG is stored as full-range JPEG, frequently with finer chroma. Raise the quality level if the footage is detailed or noisy.

Can I get the frames back out as images afterwards?

Yes, though it is better to take them from the original. Interframe coding in H.264 means most frames in the MTS depend on their neighbours, whereas the source MJPEG holds each one whole. MJPEG to JPG extracts stills straight from the original capture.

How are my files handled and how long are they kept?

Files are uploaded over an encrypted connection, converted on our servers, and deleted automatically a few hours later. No sign-up, no watermark, nothing shared or made public.