Convert MJPEG to APNG Online

Convert MJPEG to APNG Online

MJPEG (Motion JPEG) stores a clip as a sequence of standalone, lossy JPEG frames — the format webcams, IP cameras, and many capture devices write by default. Converting it to APNG (Animated PNG) turns that clip into a single looping animation that drops straight into a web page, README, or chat with full 24-bit color, 8-bit alpha transparency, and lossless frames. Because each MJPEG frame is already a discrete image, the conversion re-encodes those frames into APNG without GIF's 256-color penalty, so smooth gradients and sharp edges survive.

How to Convert MJPEG to APNG

1. Upload Your MJPEG File: Drag and drop your .mjpeg (or .mjpg) file onto the page, or click "Add Files" to browse. Files are uploaded over an encrypted connection.
2. Set the Framerate: Open Advanced Options and pick a value from the Framerate dropdown — 10 FPS is the recommended default for a smooth, compact loop; raise it toward 30 FPS for fluid motion or drop to 2-5 FPS for a slideshow feel.
3. Tune Image Quality, Resolution, and Colors: Adjust Image Quality (%) to balance sharpness against file size, scale down under Image Resolution if you don't need full size, and optionally use Colors (By Color Reduction + Dither) to shrink the output further.
4. Convert and Download: Click Convert, then download your APNG. No sign-up, no watermark.

APNG vs GIF vs Animated WebP

For lossless quality and clean transparency, APNG wins; if you mainly care about the smallest possible file for web delivery, compare with MJPEG to WebP. When universal compatibility matters most, MJPEG to GIF is the safer pick.

Frequently Asked Questions

Will converting MJPEG to APNG lose quality?

MJPEG frames are already lossy JPEG, so any compression artifacts baked into the source carry over — that's unavoidable. APNG itself is lossless, so the conversion does not add a second round of generation loss the way re-encoding to another lossy format would. Each JPEG frame is decoded and stored pixel-for-pixel inside the APNG, preserving whatever detail the source had.

Why is my APNG file larger than the original MJPEG or a GIF?

APNG is lossless and keeps full 24-bit color, so it stores more data per frame than a 256-color GIF and far more than a lossy MJPEG stream. The output is optimized with Zopfli-based compression, but a high framerate or full resolution still produces a sizeable file. To shrink it, lower the Framerate, scale down under Image Resolution, or reduce the Colors palette — and check Compress APNG afterward.

What happens in browsers that don't support APNG?

APNG is built so that a browser without animation support simply displays the first frame as a normal static PNG. Around 94.7% of browsers (Chrome 59+, Firefox 3+, Safari 8+, Edge 79+) play the full animation; the rest fall back gracefully to that first frame rather than showing a broken image.

Is APNG an official standard or just an extension?

It is now official. The W3C published the PNG Specification (Third Edition) as a Recommendation in 2025, and it formally defines the image/apng media type — so animated PNG is part of the PNG standard rather than the unofficial extension it was for years.

How is my file handled after upload?

Your MJPEG is uploaded over an encrypted connection, converted on our servers, and deleted automatically after a few hours. There's no sign-up, no watermark, and files are never shared or made public. In our testing, a 5-second 640x480 MJPEG clip at 10 FPS produced an APNG of roughly 1-3 MB depending on motion and detail.