MJPEG to DivX Converter

MJPEG to DivX — And Whether DivX Is the Target You Want

Motion JPEG keeps every frame as a full standalone JPEG and never compares one frame to the next, which is why recordings from IP cameras, capture cards and older camcorders are so much larger than the picture quality suggests. DivX is an MPEG-4 Part 2 (Advanced Simple Profile) codec from the early 2000s that does add inter-frame compression, so the conversion genuinely shrinks the file. The short answer on target choice: pick DivX only if a specific DivX-Certified DVD player, set-top box or car head unit is waiting for the file. For anything made in the last fifteen years, MJPEG to MP4 compresses better and plays in more places. One practical detail up front — the .divx you download is an AVI file under a codec-style extension, so rename it to .avi if a player refuses it.

Side-by-side Comparison

When to Pick DivX

• A DivX-Certified DVD or Blu-ray player, or a mid-2000s set-top box, is the intended playback device and rejects MP4.
• An older car head unit or portable media player lists DivX or Xvid support on the box but nothing newer.
• You are feeding a legacy editing or authoring tool that only ingests MPEG-4 Part 2 in AVI.
• You already have a DivX-based library and want the new file to match it.

When to Pick MP4 or MKV Instead

• The file is going to a phone, tablet, browser, smart TV or modern editor — all of which prefer H.264 in MP4.
• You want the smallest result at a given quality; H.264 and especially HEVC beat MPEG-4 Part 2 comfortably.
• You want the rate-control modes to behave predictably; on DivX the quality slider is a qscale, and the Quality Preset mode has nothing useful to work from on a raw MJPEG source.
• You need a container that carries chapters, multiple tracks or rich metadata — MKV does, AVI barely does.

How to Convert MJPEG to DivX

1. Upload Your MJPEG File: Drag your .mjpeg or .mjpg onto the page, or click "Add Files" to browse. Several captures can be queued with one set of settings.
2. Switch File Compression to Constraint Quality: The codec is fixed to DivX for this target. Under File Compression choose Constraint Quality, which pairs the quality field with Max bitrate — this is the mode that behaves properly on an MPEG-4 Part 2 encoder.
3. Set the Quality Value Low, Not High: The field is labelled CRF but runs 1-31 on this codec, and lower means better. Values around 2-5 keep the picture close to the source; the top of the range is heavily compressed. Optionally set Video resolution to a preset height or exact Width x Height.
4. Convert and Download: Click Convert and save the file, renaming it to .avi if a player balks. Uploads travel over an encrypted connection, are processed on our servers, and are deleted automatically after a few hours. No sign-up, no watermark.

The Quality Field Here Is a qscale, Not an x264 CRF

This is the single most common way to get a disappointing DivX file, so it is worth spelling out. MPEG-4 Part 2 has no CRF mechanism. The quality field on this page maps to the encoder's quantiser scale, which runs 1 to 31 with lower numbers meaning better quality — a completely different scale from the 16-51 CRF you may know from H.264, where 23 is a reasonable default. Typing 23 here does not give you "default quality"; it asks for near-worst quality on a 31-point scale.

Frequently Asked Questions

Why is my downloaded file called .divx instead of .avi?

Because .divx names a codec rather than a container. DivX video has to live inside something, and the container written here is AVI — so the file you download is a valid AVI carrying a codec-style extension. Renaming it to .avi changes nothing about the bytes and gets extension-driven players, media managers and editors to accept it immediately. DivX-Certified hardware generally recognises both spellings.

What audio will the DivX file have?

None, and that comes from the source rather than the target. A bare .mjpeg or .mjpg stream is a sequence of JPEG images with no audio substream at all, so there is nothing to encode no matter what the Audio Codec dropdown is set to — that control is shared across every video target on the site and simply has no input to act on here. An AVI container carries audio perfectly well; if your footage has a soundtrack, it is living in a real container such as AVI or MOV, and you should convert that file rather than an extracted elementary stream.

Why does the Quality Preset mode give me a poor result on this page?

Because Quality Preset only maps to a true constant-quality value on codecs that implement CRF — H.264, H.265, VP8, VP9 and AV1. MPEG-4 Part 2 does not, so the preset falls back to computing a target bitrate from the source's own bitrate. A raw Motion JPEG stream carries no container metadata, which means no reported bitrate and nothing sensible to scale from. Use Constraint Quality instead, where you set the quantiser and a maximum bitrate yourself.

How much smaller should I expect the DivX file to be?

Substantially smaller, though less so than a modern codec would manage. MJPEG spends full-frame bits on every frame regardless of how little changed, which is why surveillance guidance puts it at roughly 5-20x the storage of H.264. MPEG-4 Part 2 captures most of that redundancy with I, P and B frames, so static scenes shrink dramatically. It does not match H.264, which was standardised four years later specifically to improve on it — expect a DivX file noticeably larger than an H.264 encode at matched quality.

Will the output dimensions change?

Only if you ask for a resize, and then only by a pixel. When you set a resolution the encoder floors each dimension to an even value, because MPEG-4 Part 2 works on chroma-subsampled macroblocks and cannot take an odd width or height. A request for 719 pixels wide becomes 718. Leaving Video resolution on its original setting keeps the capture's own dimensions. If you want a specific frame size, enter it under Width x Height in even numbers and there is nothing to think about.

Can I convert only part of a long recording?

Yes. The Trim control takes a start point and a duration, so you can export a single incident from a long capture rather than encoding hours of empty corridor. Bear in mind that a raw MJPEG stream stores no timing information — decoders fall back to an assumed frame rate, so the timeline you are addressing may not line up with wall-clock time on the original recording. For heavier editing before conversion, the video cutter is the better starting point.

Is DivX the same thing as Xvid?

They are two implementations of the same underlying standard, MPEG-4 Part 2 Advanced Simple Profile, so the decoded picture is equivalent and most players that handle one handle the other. DivX began as commercial software and drove the "DivX-Certified" hardware badge; Xvid grew up as the open-source alternative. If your target device specifically lists one, use that; MJPEG to Xvid writes the other under the same AVI-bytes arrangement.

What happens to my upload afterwards?

It is sent over an encrypted connection, converted on our servers, and both the source and the output are deleted automatically after a few hours. Files are never shared or made public, no account is required, and no watermark is added. Since processing is server-side, the practical ceiling on a very large MJPEG recording is upload time — trimming before you convert is the fastest way to keep that manageable.