ICO to RAF Converter

Encoding: the ICO uses each size stored as a headerless BMP or as a complete PNG; RAF uses uncompressed or lossless compressed sensor data in Fujifilm's own container, and the download is a Linear DNG: demosaiced 8-bit RGB with the colour matrices raw editors need.

Bit depth: 1 to 32 bits per pixel, set per size in the ICO; RAF allows 12 to 16 bits per channel depending on the camera, and the DNG written here has 8 bits per channel, linearised.

Colour: RGB or a palette, per image in the ICO; RAF supports camera RGB from an X-Trans 6×6 or Bayer 2×2 mosaic, written here as 8-bit sRGB.

Transparency: the ICO stores it as 8-bit alpha in 32-bit and PNG entries, or a 1-bit mask in old icons; the DNG has none, so transparent areas are filled with the colour you choose.

Other images: the ICO can hold several sizes of the same picture, typically 16, 32, 48 and 256 px; only the main image is converted.

Metadata: the ICO can carry only a directory of the sizes inside, with no EXIF; RAF can carry EXIF and Fujifilm maker notes, including the Film Simulation, but nothing is copied across.

ICO is a container that bundles several sizes of the same icon (16, 32, 48, 256 px) into one file. It is still the most compatible format for website favicons and Windows app icons.

An ICO starts with a 6-byte ICONDIR (type 1 for icons) and a 16-byte entry per image giving width, height, colour count and offset. Each image is either a BMP without its file header plus an AND mask, or a complete PNG.

ICO files usually come from website favicons, Windows programs and installers.

RAF is the raw format of Fujifilm cameras, from the X series to the medium-format GFX. Most X-series bodies use an X-Trans sensor with a 6×6 colour filter pattern instead of the usual Bayer 2×2.

RAF is not TIFF at the top level: it opens with the text 'FUJIFILMCCD-RAW', then a header with the camera model and offsets to three blocks: a JPEG preview near the start of the file, a header describing the sensor layout, and the sensor data.

RAF files come from Fujifilm X-T, X-H, X-S, X-E, X100 and GFX cameras.

Forms and workflows that ask for RAF usually feed a raw editor, and each of those opens DNG as well, so the DNG can take the RAF's place. Keep the ICO if you only need to view or share the picture.

What RAF offers when it comes straight from the camera: Film Simulation baked into the embedded JPEG; Lossless compressed option on recent bodies; Large medium-format files from GFX cameras. Its drawbacks: Fujifilm's own container rather than TIFF; X-Trans demosaicing differs between raw editors; Film Simulations need camera-matching profiles in third-party editors.