Image MIME Reference
EDMICS-MMR
Fuji Xerox EDMICS-MMR
image/vnd.fujixerox.edmics-mmr
VS
X Window Dump (Legacy MIME Alias)
image/x-xwindowdump
XWD
A complete technical comparison of Fuji Xerox EDMICS-MMR 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 | EDMICS-MMR | XWD |
|---|---|---|
| Transparency (Alpha) | ✕ No | Yes |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | ✕ No | ✕ No |
| EXIF Metadata | ✕ No | ✕ No |
| ICC Color Profile | ✕ No | ✕ No |
Fuji Xerox EDMICS-MMR
image/vnd.fujixerox.edmics-mmr
Extension
.mmr.edm
Container
Fuji Xerox EDMICS Wrapper
Compression
Modified Modified READ (MMR / Group 4 Fax)
Algorithm
MMR (ITU-T T.6 / CCITT Group 4)
Color Depth
1-bit (Monochrome / Bi-level)
Developed by
Fuji Xerox Co., Ltd.
Released
1990s
Magic Bytes
Unknown (Proprietary Container wrapped around MMR bitstream)
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 | EDMICS-MMR | XWD |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
EDMICS-MMR
EDMICS-MMR Strengths
- Utilized the highly efficient MMR (Group 4) algorithm, which allowed massive, E-size engineering blueprints to be compressed into tiny file sizes suitable for 1990s hard drives and networks
- Deeply integrated into Fuji Xerox hardware and database systems for seamless scan-to-archive workflows
Limitations
- Completely proprietary and closed-source, making modern archival extraction and migration extremely difficult
- No support in modern image processing libraries like ImageMagick, libvips, or standard TIFF viewers without first stripping the proprietary header
- Strictly limited to 1-bit monochrome images
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
EDMICS-MMR
Use EDMICS-MMR when…
- Fuji Xerox EDMICS Enterprise Systems
- Archival of Large-Format Engineering Drawings
- Legacy Corporate Document Scanning Pipelines
XWD
Use XWD when…
- X Window System (X11) Display Debugging and Screenshots
- Legacy Unix/Linux System Administration