Image MIME Reference
JPX
JPEG 2000 Part 2 (Extended)
image/jpx
VS
Kodak K25 Raw Image
image/x-kodak-k25
Kodak-K25
A complete technical comparison of JPEG 2000 Part 2 (Extended) and Kodak K25 Raw Image — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | JPX | Kodak-K25 |
|---|---|---|
| Transparency (Alpha) | Yes | ✕ No |
| Animation Support | Yes | ✕ No |
| Progressive Loading | Yes | ✕ No |
| HDR Support | Yes | Yes |
| EXIF Metadata | Yes | Yes |
| ICC Color Profile | Yes | ✕ No |
JPEG 2000 Part 2 (Extended)
image/jpx
Extension
.jpx.jpf
Container
ISOBMFF / JPX (ISO/IEC 15444-2)
Compression
Lossy / Lossless
Algorithm
Discrete Wavelet Transform (DWT)
Color Depth
8-bit, 16-bit, 32-bit, 38-bit
Developed by
Joint Photographic Experts Group (JPEG)
Released
2002
Magic Bytes
00 00 00 0C 6A 50 20 20 0D 0A 87 0A ... 66 74 79 70 6A 70 78 20
Kodak K25 Raw Image
image/x-kodak-k25
Extension
.k25
Container
Proprietary Kodak Raw (TIFF-based variant)
Compression
Uncompressed / Proprietary Lossless
Algorithm
Proprietary Kodak Compression
Color Depth
10-bit, 12-bit (Per Channel)
Developed by
Eastman Kodak Company
Released
1996
Magic Bytes
Varies (Often resembles TIFF header 49 49 2A 00 or requires proprietary parsing)
Browser Support Comparison
| Browser | JPX | Kodak-K25 |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
JPX
JPX Strengths
- Removes the color space limitations of baseline JP2, adding native support for CMYK, CIE Lab, and custom vendor color spaces
- Supports multiple codestreams in a single file, allowing for rich compositing and animation
- Enables fragmented files where image data and metadata can reside in separate physical files via data references
Limitations
- Extremely complex specification makes full software implementation rare, leading to compatibility issues
- Zero web browser support, rendering it unsuitable for public internet distribution
- Often overkill for standard imaging tasks where baseline JP2 or modern alternatives like AVIF suffice
Kodak-K25
Kodak-K25 Strengths
- Historically significant format tied to the first digital camera to adopt CompactFlash memory
- Preserves original raw sensor data, allowing modern demosaicing algorithms (via LibRaw) to extract much better image quality than 1996-era software could
Limitations
- Completely obsolete and deeply proprietary, lacking modern raw format features found in DNG
- Cannot be natively viewed in web browsers or standard operating system image viewers without specialized decoders
- Subject to misidentification by automated MIME detection libraries due to structural similarities with standard TIFFs
When to choose which format
JPX
Use JPX when…
- Prepress & Commercial Printing (CMYK)
- Geospatial Data
- Archival Preservation
- Medical Imaging
Kodak-K25
Use Kodak-K25 when…
- Vintage Digital Photography Archival
- Kodak DC25 Camera Restorations
- Historical Imaging Research