Convert ORF to APNG Online

ORF to APNG Converter

ORF is the Olympus Raw Format — the unprocessed sensor file an Olympus or OM System body writes before white balance, exposure or an Art Filter look is applied. APNG is Animated PNG: an extension of PNG that stores a frame sequence losslessly in full colour, formally folded into the W3C's PNG specification Third Edition on 24 June 2025. Converting ORF to APNG means rendering each raw frame and assembling the set into one looping animation — the natural target for an interval-shot timelapse or a burst sequence, because unlike GIF it never crushes a sky down to 256 colours. Upload one file and you get a still; upload the sequence and you get the animation.

ORF Format at a Glance

APNG Format at a Glance

How to Convert ORF to APNG

1. Upload Your ORF Files: Drag and drop the Olympus .orf files onto the page or click "Add Files". Upload order is playback order, so add an interval or burst sequence in shooting order.
2. Set the Framerate: Pick a value from the Framerate dropdown — 10 FPS is the default; 1 FPS gives a slideshow pace and 50 FPS the fastest playback. The delay written into each frame is exactly one over this number of a second.
3. Choose Combine and Image resolution: Leave "Combine?" on "Single animation" to build one APNG from every file, or switch to "Individual files" for one output per photo. Under Image resolution, "Keep original" holds native pixels, or set a Preset, a Width, a Height or a Width x Height to shrink a large sequence.
4. Convert and Download: Click Convert and save the .apng. Files upload over an encrypted connection, are processed on our servers, and are deleted automatically after a few hours. No sign-up, no watermark.

What Happens to Each Frame

Three things happen between your raw file and the finished animation, and none of them are exposed as a setting:

• Every ORF is demosaiced and re-rendered to a clean PNG first. That render bakes in white balance, exposure and tone. The raw latitude that lets you rescue a blown sky in OM Workspace does not survive into the APNG, so keep the .orf as your master and treat the animation as an export.
• The long edge is capped at 4096 pixels. A 20-megapixel Micro Four Thirds frame at 5184 × 3888 comes out of the render step at 4096 × 3072; smaller files pass through untouched. Dimensions are also rounded down to even numbers. If you want something smaller than that cap, set it explicitly under Image resolution.
• Mismatched frames are letterboxed, never cropped. The assembler cannot resize, so frames of different sizes are centred on a common canvas — the largest width by the largest height across the set, or whatever you asked for — with the padding left transparent. Aspect ratio is always preserved.

There are no quality, colour-palette, compression-level or bit-depth controls on this page, and that is by design rather than an omission: APNG frames are stored losslessly, so there is no quality dial to turn. After assembly the file is run through a Zopfli-based optimiser on a best-effort basis, which shrinks it without touching a pixel.

APNG vs GIF for Photographic Frames

For rendered raw photography the palette step is the deciding factor: a sunset gradient that occupies thousands of tones in the ORF has to be squeezed into 256 entries for GIF, which is where the banding comes from. If you need the animation to play absolutely everywhere including very old software, ORF to GIF is the compatibility choice.

Frequently Asked Questions

Why did my single ORF come out as a still image instead of an animation?

Because a one-frame animation is not an animation. The assembler this converter uses collapses duplicate frames, so a single uploaded photo produces a plain static PNG carrying the .apng name — no acTL chunk, nothing to play. We ran the same assembler, apngasm 2.91, over two identical copies of one frame and it reports "frame 1 of 1" and writes no animation control chunk at all. Upload two or more ORF files and you get a real APNG with the animation chunks present.

How do I control the order the frames play in?

By the order you add the files. Upload order is playback order, which is what matters for an interval sequence — add them in shooting order rather than dropping a folder in and hoping. Each file becomes exactly one frame, and the Framerate setting decides how long each of them is held.

Can I stop the animation from looping forever?

Not from this page. The loop count is written as zero, which the APNG specification defines as "play indefinitely", and there is no control exposed for it. If a fixed number of plays matters, you will need a dedicated APNG editor after the fact — the value lives in a single field of the acTL chunk.

Will the APNG be at my camera's full resolution?

Only if your frames are already 4096 pixels or smaller on the long edge. The render step that turns each raw file into a frame caps the long edge at 4096 px, so a 5184 × 3888 Micro Four Thirds file becomes 4096 × 3072. That is usually welcome — an uncapped multi-frame APNG from 20-megapixel raws would be enormous — but if you need something specific, set it yourself under Image resolution rather than relying on the cap.

Why are there no quality or colour settings on this page?

Because APNG stores its frames losslessly, so the quality dials that appear on JPEG, WebP or AVIF targets have nothing to act on. Colour-palette reduction is a compression tool that belongs on the compress side, not on a raw-to-animation convert. The only levers that change the output size here are Image resolution and how many frames you upload.

Do I lose the raw editing latitude by converting?

Yes, and permanently for that copy. An ORF holds an undemosaiced sensor readout — typically 12 bits per pixel — which is why white balance, exposure and highlight recovery are still negotiable long after the shutter fired. Producing a viewable frame means demosaicing it and baking those decisions in. Keep the original .orf files; convert copies. For a high-bit-depth still that keeps more room to edit, ORF to TIFF is the better target.

What happens in a browser or app that does not support APNG?

It shows the first frame. The APNG chunks are ancillary, so a decoder that does not recognise them ignores them and renders the base image as an ordinary PNG — that backwards compatibility is written into the specification. In practice this affects very little: caniuse currently puts APNG support at 95.94% of global traffic, with Chrome, Firefox, Safari and Edge all covered for years.

Can I convert an APNG back to ORF?

No, and no tool can. A raw file is a record of what a specific sensor measured through a specific colour filter array, complete with the camera's own metadata — once it has been demosaiced into RGB pixels there is nothing to reconstruct it from. ORF is an input-only format here for that reason. If you want a still frame out of the sequence instead, ORF to PNG renders each photo on its own.

How are my files handled during conversion?

Files are uploaded over an encrypted connection, rendered and assembled on our servers, and deleted automatically after a few hours — no sign-up, no watermark, never shared or made public. The practical constraint on a long sequence is upload size and time, since Olympus raw files commonly run into the tens of megabytes each.