Image MIME Reference
Kodak-KDC
Kodak KDC Raw Image
image/x-kodak-kdc
VS
Radiance HDR
image/vnd.radiance
Radiance
A complete technical comparison of Kodak KDC Raw Image and Radiance HDR — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | Kodak-KDC | Radiance |
|---|---|---|
| Transparency (Alpha) | ✕ No | ✕ No |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | Yes | Yes |
| EXIF Metadata | Yes | ✕ No |
| ICC Color Profile | Yes | ✕ No |
Kodak KDC Raw Image
image/x-kodak-kdc
Extension
.kdc
Container
TIFF/EP
Compression
Uncompressed / Proprietary Lossless
Algorithm
NoneLossless JPEG (ITU-T81)Proprietary Kodak Compression
Color Depth
10-bit, 12-bit (Per Channel)
Developed by
Eastman Kodak Company
Released
1995
Magic Bytes
49 49 2A 00 or 4D 4D 00 2A
Radiance HDR
image/vnd.radiance
Extension
.hdr.pic.rgbe.xyze
Container
Radiance Information Header
Compression
Run-Length Encoding (RLE) / Uncompressed
Algorithm
Adaptive Run-Length Encoding (RLE)
Color Depth
32-bit (8-bit per channel RGB + 8-bit shared Exponent)
Developed by
Greg Ward (Lawrence Berkeley National Laboratory)
Released
1989
Magic Bytes
23 3F 52 41 44 49 41 4E 43 45
Browser Support Comparison
| Browser | Kodak-KDC | Radiance |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
Kodak-KDC
Kodak-KDC Strengths
- Preserves original raw sensor data, allowing modern demosaicing software to extract significantly more detail and dynamic range than the camera's built-in JPEG engine could at the time
- Utilizes the standard TIFF container structure, ensuring broad compatibility with open-source decoding libraries (like LibRaw)
Limitations
- Completely obsolete proprietary format tied to a defunct line of consumer digital cameras
- Subject to widespread misidentification by automated MIME detection libraries due to structural similarities with standard TIFFs
- Cannot be natively viewed in web browsers or standard operating system image viewers without specialized decoders
Radiance
Radiance Strengths
- Universally supported by almost every 3D modeling software, renderer, and game engine in existence
- RGBE encoding offers a brilliant balance between High Dynamic Range capability and small file size (compared to 32-bit float OpenEXR)
- Simple, easy-to-parse ASCII header followed by straightforward RLE binary data
Limitations
- Does not support alpha transparency (no way to store an isolated light source with a transparent background)
- The shared exponent architecture can occasionally introduce banding or color artifacts in extreme edge cases compared to true 16-bit/32-bit floating-point formats like OpenEXR
- Zero native browser support for 2D viewing
When to choose which format
Kodak-KDC
Use Kodak-KDC when…
- Vintage Digital Photography Archival
- Kodak DC and EasyShare P-Series Raw Post-Processing
- Historical Imaging Research
Radiance
Use Radiance when…
- Image-Based Lighting (IBL)
- 3D Environment Maps (HDRI Skydomes)
- Lighting Simulation
- VFX and CGI Rendering