Image MIME Reference
DNG
Adobe Digital Negative
image/x-adobe-dng
VS
Kodak KDC Raw Image
image/x-kodak-kdc
Kodak-KDC
A complete technical comparison of Adobe Digital Negative and Kodak KDC Raw Image — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | DNG | Kodak-KDC |
|---|---|---|
| Transparency (Alpha) | Yes | ✕ No |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | Yes | Yes |
| EXIF Metadata | Yes | Yes |
| ICC Color Profile | Yes | Yes |
Adobe Digital Negative
image/x-adobe-dng
Extension
.dng
Container
TIFF/EP
Compression
Lossless JPEG / Deflate / Lossy JPEG (DNG 1.4+)
Algorithm
Lossless JPEG (Standard)Lossy JPEG (Compression option)Uncompressed
Color Depth
12-bit, 14-bit, 16-bit, 32-bit (Floating Point HDR)
Developed by
Adobe Systems
Released
2004
Magic Bytes
49 49 2A 00 or 4D 4D 00 2A
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
Browser Support Comparison
| Browser | DNG | Kodak-KDC |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
DNG
DNG Strengths
- Openly documented specification guarantees long-term archival accessibility, freeing photographers from proprietary manufacturer lock-in
- Lossless compression algorithms often result in files 15-20% smaller than uncompressed proprietary raw formats
- Natively supported by modern smartphone operating systems (iOS and Android) for high-end mobile photography
Limitations
- Conversion from proprietary raw to DNG takes processing time and can strip specific, proprietary manufacturer metadata (like active D-Lighting or in-camera lens corrections)
- File sizes are massive compared to standard JPEGs or HEIC files
- Cannot be rendered natively in web browsers without server-side processing or WebAssembly decoders
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
When to choose which format
DNG
Use DNG when…
- Digital Photography Archival
- Mobile Raw Capture (iOS ProRAW / Android Camera2 API)
- Cross-Platform Raw Editing Workflows
Kodak-KDC
Use Kodak-KDC when…
- Vintage Digital Photography Archival
- Kodak DC and EasyShare P-Series Raw Post-Processing
- Historical Imaging Research