Image MIME Reference
Olympus-ORF
Olympus Raw Format
image/x-olympus-orf
VS
Sony SRF Raw Image
image/x-sony-srf
Sony-SRF
A complete technical comparison of Olympus Raw Format and Sony SRF Raw Image — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | Olympus-ORF | Sony-SRF |
|---|---|---|
| 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 |
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)
Sony SRF Raw Image
image/x-sony-srf
Extension
.srf
Container
TIFF-based (Proprietary)
Compression
Uncompressed
Algorithm
None
Color Depth
12-bit (Per Channel)
Developed by
Sony Corporation
Released
2003
Magic Bytes
49 49 2A 00
Browser Support Comparison
| Browser | Olympus-ORF | Sony-SRF |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
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
Sony-SRF
Sony-SRF Strengths
- Retains perfectly raw, unprocessed sensor data from legacy early-2000s cameras, allowing modern raw processors to extract much better dynamic range and color than the camera's original internal JPEG engine could
- Utilizes a standard TIFF container structure, ensuring broad compatibility with community-maintained open-source decoding libraries like LibRaw
Limitations
- Completely obsolete format that has long been abandoned in favor of ARW
- MIME detection via magic bytes is unreliable due to TIFF header spoofing, requiring deeper EXIF inspection for accurate routing
- Cannot be natively viewed in web browsers or standard operating system image viewers without specialized decoders
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
Sony-SRF
Use Sony-SRF when…
- Legacy Sony Cyber-shot Photography
- Non-destructive Image Post-Processing
- Early 2000s Raw Imaging Archival