A simple tool, for a strict principle.
MediaBay was born of a frustration: converting an image shouldn't mean sending that image to the other side of the world. We built the opposite — a converter that does its job on your machine, no detour.
Our only promise: your images never leave your device. It's technically guaranteed — and it's the sole reason this service exists.
Why this tool exists.
Online image converters almost all follow the same pattern: you upload your photo, a server processes it, and you download it a few seconds later. That model creates three problems:
- Privacy. Your photos pass through a third-party server whose jurisdiction, backups and operators you don't control.
- Slowness. Uploading a 30 MB file often takes longer than the conversion itself.
- Hidden costs. To stay free, many of these services indirectly monetize the uploaded content.
MediaBay solves all three problems by removing the upload step. The computation happens right in your browser, through native and WebAssembly decoders, without any of your pixels reaching our servers.
How it works.
Three key technologies make processing entirely local while keeping it fast:
HTML5 Canvas & OffscreenCanvas
For traditional formats (JPG, PNG, WebP, GIF, BMP), the browser has native decoders and encoders, run inside an OffscreenCanvas off the main thread. No external dependency required.
WebAssembly
For the newer formats — HEIC (Apple iPhone) and AVIF (AV1 Image Format) — we bundle the libheif and libavif libraries compiled to WebAssembly. The native C code runs at near-machine speed, right in your browser.
Web Workers
All decoding and encoding happens inside an isolated Web Worker. The direct result: the interface stays smooth even while converting a 100 MB file.
MediaBay's server side only serves the HTML page, the CSS, the scripts and the WebAssembly binaries. None of our endpoints accept a file as input — by design.
Markovic Technologies.
MediaBay is published by Markovic Technologies, a French company specialized in building web tools focused on performance, privacy and usability.
Our approach is simple: we build tools we'd want to use ourselves. That means favoring local processing whenever it's technically possible, hosting in Europe, and limiting data collection to the strict minimum needed to run and fund the service.
- Publisher
- Markovic Technologies — French company
- Hosting
- OVH SAS — France & Germany (European Union)
- Stack
- Python · Flask · Vanilla JS · WebAssembly
- Contact
- contact@markovictechnologies.com