Free webp to jpg
EN
Image MIME Reference
Generic-RAW

Digital Camera Raw (Generic Linux MIME)

image/x-dcraw
VS

Nikon Electronic Format

image/x-nikon-nef
Nikon-NEF

A complete technical comparison of Digital Camera Raw (Generic Linux MIME) and Nikon Electronic Format — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.

Equal browser support

Feature Support

Feature Generic-RAW Nikon-NEF
Transparency (Alpha) ✕ No ✕ No
Animation Support ✕ No ✕ No
Progressive Loading ✕ No ✕ No
HDR Support Yes Yes
EXIF Metadata Yes Yes
ICC Color Profile Yes Yes
Digital Camera Raw (Generic Linux MIME)
image/x-dcraw
Extension
.raw
Container Varies (Predominantly TIFF/EP)
Compression Lossless / Uncompressed
Algorithm
Varies (Often Lossless JPEG ITU-T81 or uncompressed)
Color Depth 12-bit, 14-bit, 16-bit
Developed by freedesktop.org (MIME mapping) / Dave Coffin (dcraw tool)
Released 1997
Magic Bytes
Varies by vendor format
Full Generic-RAW reference →
Nikon Electronic Format
image/x-nikon-nef
Extension
.nef
Container TIFF
Compression Uncompressed / Lossless Compressed / Lossy Compressed (High Efficiency)
Algorithm
NoneNikon Proprietary LosslessNikon High Efficiency Lossy
Color Depth 12-bit (Per Channel), 14-bit (Per Channel)
Developed by Nikon Corporation
Released 1999
Magic Bytes
49 49 2A 00 or 4D 4D 00 2A
Full Nikon-NEF reference →

Browser Support Comparison

Browser Generic-RAW Nikon-NEF
Chrome Chrome
✕ ✕
Firefox Firefox
✕ ✕
Safari Safari
✕ ✕
Edge Edge
✕ ✕
IE IE (Legacy)
✕ ✕
Generic-RAW

Generic-RAW Strengths

  • Provides a unified, highly useful catch-all MIME type for application developers who just need to know if a file is a raw image, rather than tracking 50+ individual camera extensions
  • Deeply integrated into the Linux desktop ecosystem, ensuring file manager thumbnails work seamlessly via tools like ufraw-thumbnailer
Limitations
  • Not an official IANA standard
  • Can cause conflicts where standard TIFF files are misidentified as raw camera data by over-aggressive MIME sniffers
  • The underlying 'dcraw' tool was abandoned by its creator in 2018 (though its successor, LibRaw, continues to maintain the ecosystem)
Nikon-NEF

Nikon-NEF Strengths

  • Retains maximum sensor data, allowing extreme recovery of highlights and shadows that would be permanently lost in a JPEG
  • White balance, sharpening, and color profiling are saved as metadata instructions rather than 'baked in', meaning they can be completely altered in post-production without degrading the image
  • Embeds a high-quality JPEG preview inside the raw file for rapid culling and viewing
Limitations
  • Proprietary format means it requires constant updates to raw processing engines every time Nikon releases a new camera model
  • Produces very large file sizes (often 20MB to 50MB+ per image depending on sensor resolution and bit-depth)
  • Cannot be directly embedded into web pages or used in standard HTML/CSS contexts

When to choose which format

Generic-RAW
Use Generic-RAW when…
  • Linux Desktop File Associations (GNOME/KDE)
  • Thumbnail Generation for Raw Images (UFRaw/LibRaw)
  • Server-side Image Processing Fallbacks
Nikon-NEF
Use Nikon-NEF when…
  • Professional Digital Photography
  • Non-destructive Image Post-Processing
  • High Dynamic Range (HDR) Imaging Archival

More comparisons

Generic-RAW vs ACES → Nikon-NEF vs ACES → Generic-RAW vs APNG → Nikon-NEF vs APNG → Generic-RAW vs AVCI → Nikon-NEF vs AVCI → Generic-RAW vs AVCS → Nikon-NEF vs AVCS → Generic-RAW vs AVIF → Nikon-NEF vs AVIF → All comparisons →
Share this comparison