Image MIME Reference
EDMICS-MMR
Fuji Xerox EDMICS-MMR
image/vnd.fujixerox.edmics-mmr
VS
Progressive JPEG (Legacy IE Alias)
image/pjpeg
PJPEG
A complete technical comparison of Fuji Xerox EDMICS-MMR and Progressive JPEG (Legacy IE Alias) — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
PJPEG wins on browser support
Feature Support
| Feature | EDMICS-MMR | PJPEG |
|---|---|---|
| Transparency (Alpha) | ✕ No | ✕ No |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | Yes |
| HDR Support | ✕ No | ✕ No |
| EXIF Metadata | ✕ No | Yes |
| ICC Color Profile | ✕ No | Yes |
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)
Progressive JPEG (Legacy IE Alias)
image/pjpeg
Extension
.jpeg.jpg.pjpeg.pjp.jfif
Container
JPEG (ISO/IEC 10918-1)
Compression
Lossy (DCT)
Algorithm
Discrete Cosine Transform (DCT)
Color Depth
8-bit, 12-bit
Developed by
Joint Photographic Experts Group / Microsoft (Alias)
Released
1992
Magic Bytes
FF D8 FF E0 (JFIF) / FF D8 FF E1 (Exif)
Browser Support Comparison
| Browser | EDMICS-MMR | PJPEG |
|---|---|---|
|
|
✕ |
✓ All
|
|
|
✕ |
✓ All
|
|
|
✕ |
✓ All
|
|
|
✕ |
✓ All
|
|
|
✕ |
✓
|
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
PJPEG
PJPEG Strengths
- Progressive JPEGs (which this MIME type attempted to describe) provide excellent perceived loading speeds on slow connections by rendering a low-resolution preview first
- Files sent with this MIME type are fully backwards compatible with any standard JPEG decoder
Limitations
- It is a non-standard MIME type that violates IANA specifications
- Causes strict file upload validation scripts to fail if not explicitly whitelisted or mapped
- Creates unnecessary confusion, as the official image/jpeg MIME type already fully encompasses progressive encoding
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
PJPEG
Use PJPEG when…
- Legacy Internet Explorer File Uploads
- Progressive Image Rendering (Historical context)