Image MIME Reference
Kodak-K25
Kodak K25 Raw Image
image/x-kodak-k25
VS
Portable Network Graphics (Legacy MIME)
image/x-png
PNG
A complete technical comparison of Kodak K25 Raw Image and Portable Network Graphics (Legacy MIME) — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
PNG wins on browser support
Feature Support
| Feature | Kodak-K25 | PNG |
|---|---|---|
| Transparency (Alpha) | ✕ No | Yes |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | Yes |
| HDR Support | Yes | Yes |
| EXIF Metadata | Yes | Yes |
| ICC Color Profile | ✕ No | Yes |
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)
Portable Network Graphics (Legacy MIME)
image/x-png
Extension
.png
Container
PNG Chunk Structure (IHDR, IDAT, IEND)
Compression
Deflate (Lossless)
Algorithm
Deflate (LZ77)
Color Depth
1-bit to 16-bit (Grayscale), 8-bit (Indexed Palette), 24-bit (True Color), 32-bit (True Color with Alpha), 48-bit (High Color), 64-bit (High Color with Alpha)
Developed by
PNG Development Group
Released
1996
Magic Bytes
89 50 4E 47 0D 0A 1A 0A
Browser Support Comparison
| Browser | Kodak-K25 | PNG |
|---|---|---|
Chrome
|
✕ |
✓ 1
|
Firefox
|
✕ |
✓ 1
|
Safari
|
✕ |
✓ 1
|
Edge
|
✕ |
✓ 12
|
IE (Legacy)
|
✕ |
✓
|
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
PNG
PNG Strengths
- The underlying format provides flawless, lossless compression and perfect 8-bit alpha channel transparency
- Universally supported by every modern operating system, image editor, and web browser
Limitations
- The 'image/x-png' string is an obsolete vendor quirk that forces backend developers to write redundant normalization logic in file upload scripts
- If left unnormalized, strict MIME validators or content security policies on modern systems may incorrectly reject valid PNG files
When to choose which format
Kodak-K25
Use Kodak-K25 when…
- Vintage Digital Photography Archival
- Kodak DC25 Camera Restorations
- Historical Imaging Research
PNG
Use PNG when…
- Legacy Internet Explorer File Uploads
- Older ASP/PHP Web Applications
- Lossless Web Graphics