Image MIME Reference
CGM
Computer Graphics Metafile
image/cgm
VS
Kodak KDC Raw Image
image/x-kodak-kdc
Kodak-KDC
A complete technical comparison of Computer Graphics Metafile 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 | CGM | Kodak-KDC |
|---|---|---|
| Transparency (Alpha) | Yes | ✕ No |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | ✕ No | Yes |
| EXIF Metadata | ✕ No | Yes |
| ICC Color Profile | Yes | Yes |
Computer Graphics Metafile
image/cgm
Extension
.cgm
Container
CGM
Compression
Uncompressed / Binary / Character / Clear Text
Algorithm
Deflate (in some WebCGM profiles)
Color Depth
8-bit, 16-bit, 24-bit, 32-bit
Developed by
ISO / IEC
Released
1987
Magic Bytes
00 20 (Binary) / 42 45 47 49 4E 20 4D 45 54 41 46 49 4C 45 (Clear Text)
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 | CGM | Kodak-KDC |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
CGM
CGM Strengths
- Strictly standardized by ISO, ensuring long-term archiving and cross-platform compatibility in engineering
- Excellent support for rich metadata, hyperlinks, and technical hotspots via the WebCGM profile
- Can store complex 2D geometry, rasters, and text in a single lightweight file
Limitations
- Multiple encoding schemes (Binary, Character, Clear Text) make parser development difficult
- Zero native support in modern web browsers without third-party plugins
- Largely replaced by SVG for general-purpose 2D vector graphics on the web
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
CGM
Use CGM when…
- Technical Illustrations
- Aerospace & Defense (S1000D)
- CAD/CAM
- Geophysics
Kodak-KDC
Use Kodak-KDC when…
- Vintage Digital Photography Archival
- Kodak DC and EasyShare P-Series Raw Post-Processing
- Historical Imaging Research