PJPEG to RAS Converter
FileFlip converts PJPEG to RAS entirely inside your browser, using ImageMagick compiled to WebAssembly. The file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. That means no file-size limit, no queue and no account.
How do I convert a PJPEG file to RAS?#
- Drop your PJPEG file onto the converter at the top of this page, or click it to pick one from your computer. You can add as many as you like.
- Leave the target set to RAS and the conversion starts on its own. FileFlip downloads 14.1 MB of WebAssembly the first time and nothing after that, then runs ImageMagick on your own machine.
- Save the RAS file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting PJPEG to RAS lose quality?#
RAS is a lossless format, so nothing further is lost here, but nothing is recovered either. Whatever the PJPEG encoder already threw away is gone, and the RAS file will usually be several times larger for exactly the same content.
Is it safe to convert PJPEG files online?#
Yes, because nothing is uploaded. FileFlip converts PJPEG files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What PJPEG to RAS actually does to the file#
Converting PJPEG to RAS runs on ImageMagick, downloads 14.1 MB of WebAssembly the first time and nothing after that, writes a lossless file that cannot recover what the source already discarded, and drops EXIF metadata and ICC colour profile.
| Engine | ImageMagick |
|---|---|
| Conversion path | One step: PJPEG → RAS |
| Downloaded to your browser | 14.1 MB, once, then cached by your browser |
| Quality | Lossless output, but nothing is recovered |
| You get back | One file |
| Where it runs | In a background worker, so the page stays responsive |
What survives the conversion
| What is in the file | This conversion | Why |
|---|---|---|
| EXIF metadata | Dropped | The target format has nowhere to put it. |
| ICC colour profile | Dropped | The target format has nowhere to put it. |
What is a PJPEG file?#
PJPEG is progressive JPEG, a JPEG encoding choice rather than a different file format, where the image is built up through several increasingly detailed scans across the whole picture instead of filling in top to bottom in one pass.
Choose progressive encoding for images shown over a slow or uncertain connection, where a quick blurry preview beats a slow top-down reveal.
Convert to baseline JPEG when a downstream tool or embedded device only supports the simpler sequential scan order.
What is a RAS file?#
A RAS file is a Sun Raster bitmap, the raw framebuffer image format Sun Microsystems built into SunOS workstations, and it is byte-for-byte identical to the format most tools also recognise under the .sun extension.
Open a RAS file when it comes from legacy Sun or Solaris workstation software, or from an old dataset captured directly off a SunOS framebuffer.
Convert RAS to PNG or TIFF for anything beyond archival viewing, since almost no current software or web platform accepts Sun Raster natively.
PJPEG to RAS questions people ask#
What is PJPEG?
PJPEG is progressive JPEG, a JPEG file encoded in a handful of increasingly detailed scans instead of one pass from top to bottom. It's still a JPEG file, just encoded differently, and opens anywhere JPEG does.
What's the difference between PJPEG and a regular JPEG?
A regular, baseline JPEG fills the image in from top to bottom as it loads. PJPEG encodes several scans of the whole picture, each adding sharper detail, so a rough version of the entire image appears almost immediately and refines as more data arrives.
Does progressive JPEG reduce image quality?
No, PJPEG uses the same lossy JPEG compression as baseline JPEG at a given quality setting, and often produces a slightly smaller file because each scan can use its own optimized Huffman table.
Is a RAS file the same as a SUN file?
Yes. A RAS file and a SUN file are the same Sun Raster format, identified by the same magic number and header layout, just saved under two different extensions that various tools have used over the years.