Image MIME Reference
JPEG-XR
JPEG XR (HD Photo)
image/vnd.ms-photo
VS
Kodak KDC Raw Image
image/x-kodak-kdc
Kodak-KDC
A complete technical comparison of JPEG XR (HD Photo) 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 | JPEG-XR | Kodak-KDC |
|---|---|---|
| Transparency (Alpha) | Yes | ✕ No |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | Yes | ✕ No |
| HDR Support | Yes | Yes |
| EXIF Metadata | Yes | Yes |
| ICC Color Profile | Yes | Yes |
JPEG XR (HD Photo)
image/vnd.ms-photo
Extension
.jxr.wdp.hdp
Container
TIFF-like Image File Directory (IFD)
Compression
Lossy (Lapped Bi-orthogonal Transform) / Lossless
Algorithm
Lapped Bi-orthogonal Transform (LBT)
Color Depth
8-bit (Grayscale, RGB, CMYK), 16-bit, 32-bit Floating Point (HDR)
Developed by
Microsoft Corporation (later Joint Photographic Experts Group)
Released
2006
Magic Bytes
49 49 BC 01
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 | JPEG-XR | Kodak-KDC |
|---|---|---|
|
|
✕ | ✕ |
|
|
✕ | ✕ |
|
|
✕ | ✕ |
|
|
✕ | ✕ |
|
|
✓
|
✕ |
JPEG-XR
JPEG-XR Strengths
- Excellent support for 16-bit and 32-bit floating-point HDR images without massive file size bloat
- Native support for alpha transparency, which standard JPEG fundamentally lacks
- Computational complexity for decoding/encoding is relatively low, making it hardware-friendly
Limitations
- Suffered a complete failure of adoption in the web browser market outside of Microsoft's ecosystem
- Fully superseded by modern, open formats like WebP, AVIF, and JPEG XL which offer better compression and universal browser support
- Multiple file extensions (.wdp, .hdp, .jxr) and MIME types cause confusion and parsing fragmentation
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
JPEG-XR
Use JPEG-XR when…
- Legacy Windows Desktop Backgrounds
- XPS (XML Paper Specification) Documents
- Early High Dynamic Range (HDR) Photography
- DirectX Textures
Kodak-KDC
Use Kodak-KDC when…
- Vintage Digital Photography Archival
- Kodak DC and EasyShare P-Series Raw Post-Processing
- Historical Imaging Research