Free webp to jpg
Image MIME Reference
Fuji-RAF

Fujifilm RAW Image

image/x-fuji-raf
VS

JPEG Network Graphics

image/x-jng
JNG

A complete technical comparison of Fujifilm RAW Image and JPEG Network Graphics — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.

Equal browser support

Feature Support

Feature Fuji-RAF JNG
Transparency (Alpha) ✕ No Yes
Animation Support ✕ No ✕ No
Progressive Loading ✕ No Yes
HDR Support Yes ✕ No
EXIF Metadata Yes Yes
ICC Color Profile Yes Yes
Fujifilm RAW Image
image/x-fuji-raf
Extension
.raf
Container Proprietary RAF Container
Compression Uncompressed / Lossless Compressed / Lossy Compressed (Modern firmware)
Algorithm
NoneProprietary LosslessProprietary Lossy
Color Depth 14-bit (Per Channel - X-Series), 16-bit (Per Channel - GFX Series)
Developed by Fujifilm Corporation
Released 2000
Magic Bytes
46 55 4A 49 46 49 4C 4D 43 43 44 2D 52 41 57 20
Full Fuji-RAF reference →
JPEG Network Graphics
image/x-jng
Extension
.jng
Container PNG-style Chunk Structure (JHDR, JDAT, IDAT, IEND)
Compression Lossy (JPEG/DCT for color) / Lossless (Deflate for alpha mask)
Algorithm
JPEG (Discrete Cosine Transform)Deflate (LZ77)
Color Depth 8-bit, 12-bit, 24-bit (RGB), 32-bit (RGBA)
Developed by MNG Development Group (Glenn Randers-Pehrson et al.)
Released 2001
Magic Bytes
8B 4A 4E 47 0D 0A 1A 0A
Full JNG reference →

Browser Support Comparison

Browser Fuji-RAF JNG
Chrome Chrome
Firefox Firefox
Safari Safari
Edge Edge
IE IE (Legacy)
Fuji-RAF

Fuji-RAF Strengths

  • Retains absolute maximum sensor data, enabling massive shadow recovery and highlight protection compared to compressed in-camera JPEGs
  • Stores proprietary Fujifilm Film Simulation metadata (like Classic Chrome or Acros), allowing editors to perfectly replicate in-camera aesthetics
  • Very distinct and reliable magic header makes programmatic file detection foolproof
Limitations
  • Proprietary format requires continuous updates to third-party software (like Lightroom) whenever Fujifilm releases a new camera
  • The X-Trans sensor matrix requires highly specialized demosaicing algorithms that are extremely computationally expensive, leading to slower import and rendering times
  • Completely unsupported in standard web browsers and basic operating system image viewers
JNG

JNG Strengths

  • Solved a massive technical hurdle in the early 2000s by combining high-compression lossy photographic data with crisp, 8-bit alpha transparency
  • Utilized the highly robust, extensible chunk-based architecture of the PNG format
  • Provided an excellent, bandwidth-saving alternative to massive 32-bit transparent PNGs for web design
Limitations
  • Failed to achieve critical mass; browser vendors largely abandoned the MNG/JNG standard due to implementation complexity
  • Completely obsolete today, having been superseded by natively supported, superior formats like WebP, AVIF, and HEIC
  • Decoding requires a hybrid engine that can parse PNG chunks while simultaneously decoding a JPEG stream and a Deflate stream, complicating software support

When to choose which format

Fuji-RAF
Use Fuji-RAF when…
  • Professional Digital Photography
  • Fujifilm X-Trans Sensor Image Archival
  • High Dynamic Range (HDR) Post-Processing
JNG
Use JNG when…
  • Embedded frames in MNG animations
  • Historical web graphics requiring lossy compression with transparency
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