Image MIME Reference
Kodak-DCR
Kodak Digital Camera Raw
image/x-kodak-dcr
VS
X Window Dump (Legacy MIME Alias)
image/x-xwindowdump
XWD
A complete technical comparison of Kodak Digital Camera Raw and X Window Dump (Legacy MIME Alias) — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | Kodak-DCR | XWD |
|---|---|---|
| Transparency (Alpha) | ✕ No | Yes |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | Yes | ✕ No |
| EXIF Metadata | Yes | ✕ No |
| ICC Color Profile | Yes | ✕ No |
Kodak Digital Camera Raw
image/x-kodak-dcr
Extension
.dcr
Container
TIFF/EP
Compression
Uncompressed / Lossless JPEG
Algorithm
NoneLossless JPEG (ITU-T81)
Color Depth
12-bit (Per Channel)
Developed by
Eastman Kodak Company
Released
1998
Magic Bytes
49 49 2A 00 or 4D 4D 00 2A
X Window Dump (Legacy MIME Alias)
image/x-xwindowdump
Extension
.xwd.wd
Container
XWDHeader / XWDFileHeader Structure
Compression
Uncompressed
Algorithm
None
Color Depth
8-bit (Indexed), 16-bit (High Color), 24-bit (True Color), 32-bit (True Color with Alpha/Padding)
Developed by
MIT / X Consortium (X Window System)
Released
1987
Magic Bytes
00 00 00 64 (Typically indicates a 100-byte header size followed by version)
Browser Support Comparison
| Browser | Kodak-DCR | XWD |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
Kodak-DCR
Kodak-DCR Strengths
- Preserves the full dynamic range and uncompressed raw sensor data captured by foundational professional digital cameras
- Utilizes the standard TIFF container structure, ensuring that open-source decoders like LibRaw can easily parse and interpret the files long after official vendor support has ended
Limitations
- Completely obsolete proprietary format tied to camera hardware that is no longer manufactured
- Shares the TIFF magic header, leading to widespread misidentification by automated MIME detection libraries
- Cannot be natively viewed in web browsers or standard operating system image viewers without specialized codecs
XWD
XWD Strengths
- Provides an exact, raw pixel dump directly from the X11 display server memory without compression overhead
- Extremely fast for Unix environments to generate during low-level graphical debugging
Limitations
- Completely uncompressed, resulting in large, bloated file sizes
- Zero support in web browsers or modern desktop environments without specialized graphics translation tools
- Verbose legacy MIME strings like 'image/x-xwindowdump' require backend normalization in modern applications
When to choose which format
Kodak-DCR
Use Kodak-DCR when…
- Vintage Professional Digital Photography (Kodak DCS series)
- Non-destructive Image Post-Processing
- Raw Imaging Archival
XWD
Use XWD when…
- X Window System (X11) Display Debugging and Screenshots
- Legacy Unix/Linux System Administration