Free webp to jpg
EN
Image MIME Reference
Sigma-X3F

Sigma X3F RAW Image

image/x-sigma-x3f
VS

Sony SR2 Raw Image

image/x-sony-sr2
Sony-SR2

A complete technical comparison of Sigma X3F RAW Image and Sony SR2 Raw Image — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.

Equal browser support

Feature Support

Feature Sigma-X3F Sony-SR2
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
Sigma X3F RAW Image
image/x-sigma-x3f
Extension
.x3f
Container Foveon Proprietary Header
Compression Uncompressed / Proprietary Lossless
Algorithm
NoneFoveon Proprietary Huffman-based
Color Depth 12-bit (Per Channel), 14-bit (Per Channel)
Developed by Foveon, Inc. / Sigma Corporation
Released 2002
Magic Bytes
46 4F 56 62
Full Sigma-X3F reference →
Sony SR2 Raw Image
image/x-sony-sr2
Extension
.sr2
Container TIFF-based (Proprietary)
Compression Uncompressed / Sony Proprietary Lossless
Algorithm
NoneSony Proprietary Lossless
Color Depth 12-bit (Per Channel)
Developed by Sony Corporation
Released 2005
Magic Bytes
49 49 2A 00
Full Sony-SR2 reference →

Browser Support Comparison

Browser Sigma-X3F Sony-SR2
Chrome Chrome
✕ ✕
Firefox Firefox
✕ ✕
Safari Safari
✕ ✕
Edge Edge
✕ ✕
IE IE (Legacy)
✕ ✕
Sigma-X3F

Sigma-X3F Strengths

  • Provides absolute per-pixel color accuracy without the interpolation artifacts or moiré patterns typical of Bayer-sensor RAW files
  • Unique 'FOVb' magic byte signature prevents accidental misidentification by standard file sniffers, unlike many TIFF-based raw formats
  • Incredible sharpness and detail resolution at the raw sensor level
Limitations
  • Decoding is extremely computationally expensive and completely proprietary, meaning third-party software often struggles to match the color science of Sigma's own (famously slow) Photo Pro application
  • Massive file sizes because it records three complete RGB channels for every single spatial pixel coordinate
  • Zero support in web browsers or standard OS image viewers
Sony-SR2

Sony-SR2 Strengths

  • Retains raw, unprocessed sensor data from legacy cameras, allowing modern raw processors to extract vastly superior image quality than what was possible in 2005
  • Utilizes a standard TIFF container structure, ensuring that community-maintained open-source decoding libraries (like LibRaw) can easily parse and maintain support for it indefinitely
Limitations
  • Completely obsolete format that has not been utilized in a new camera release in over a decade
  • MIME detection via magic bytes is unreliable due to TIFF header spoofing, requiring deeper EXIF inspection
  • Cannot be natively viewed in web browsers or standard operating system image viewers without specialized decoders

When to choose which format

Sigma-X3F
Use Sigma-X3F when…
  • Professional Digital Photography
  • Sigma / Foveon High-Acuity Imaging
  • Non-destructive RAW Post-Processing
Sony-SR2
Use Sony-SR2 when…
  • Legacy Sony Cyber-shot/Alpha Photography
  • Non-destructive Image Post-Processing
  • Raw Imaging Archival

More comparisons

Sigma-X3F vs ACES → Sony-SR2 vs ACES → Sigma-X3F vs APNG → Sony-SR2 vs APNG → Sigma-X3F vs AVCI → Sony-SR2 vs AVCI → Sigma-X3F vs AVCS → Sony-SR2 vs AVCS → Sigma-X3F vs AVIF → Sony-SR2 vs AVIF → All comparisons →
Share this comparison