Image MIME Reference
Olympus-ORF
Olympus Raw Format
image/x-olympus-orf
VS
Silicon Graphics Image
image/sgi
SGI
A complete technical comparison of Olympus Raw Format and Silicon Graphics Image — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | Olympus-ORF | SGI |
|---|---|---|
| Transparency (Alpha) | ✕ No | Yes |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | Yes | ✕ No |
| EXIF Metadata | Yes | ✕ No |
| ICC Color Profile | Yes | ✕ No |
Olympus Raw Format
image/x-olympus-orf
Extension
.orf
Container
TIFF-based (with proprietary variants)
Compression
Uncompressed / Proprietary Lossless
Algorithm
NoneOlympus Proprietary Lossless
Color Depth
12-bit (Per Channel)
Developed by
Olympus Corporation (Now OM Digital Solutions)
Released
2000
Magic Bytes
49 49 52 4F (IIRO) or 4D 4D 4F 52 (MMOR) or 49 49 53 52 (IIRS)
Silicon Graphics Image
image/sgi
Extension
.sgi.rgb.rgba.bw.int.inta
Container
SGI Image Format
Compression
Uncompressed / Lossless (Run-Length Encoding)
Algorithm
RLENone
Color Depth
8-bit, 16-bit (Per Channel)
Developed by
Paul Haeberli (Silicon Graphics)
Released
1990
Magic Bytes
01 DA
Browser Support Comparison
| Browser | Olympus-ORF | SGI |
|---|---|---|
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✕ | ✕ |
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✕ | ✕ |
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|
✕ | ✕ |
|
|
✕ | ✕ |
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|
✕ | ✕ |
Olympus-ORF
Olympus-ORF 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, meaning they can be completely altered in post-production
- Unique magic byte signatures make programmatic file sniffing highly reliable compared to other camera manufacturers' TIFF-spoofing headers
Limitations
- Proprietary format means it requires constant updates to raw processing engines every time a new camera model is released
- Produces very large file sizes (often 15MB to 30MB+ per image depending on sensor resolution)
- Cannot be directly embedded into web pages or used in standard HTML/CSS contexts
SGI
SGI Strengths
- Pioneered multi-channel and 16-bit per channel imaging capabilities required for high-end 1990s visual effects
- Extremely robust and simple header structure
- Reliable Run-Length Encoding provided solid lossless compression for flat-shaded 3D renders
Limitations
- Completely obsolete for modern web and application development
- Zero native web browser compatibility
- Largely replaced by TIFF and OpenEXR in modern professional VFX and 3D pipelines
When to choose which format
Olympus-ORF
Use Olympus-ORF when…
- Professional Digital Photography
- Non-destructive Image Post-Processing
- High Dynamic Range (HDR) Imaging Archival
SGI
Use SGI when…
- Legacy 3D Animation & VFX
- Silicon Graphics IRIX Workflows
- Historical CGI Archiving