Image MIME Reference
EDMICS-MMR
Fuji Xerox EDMICS-MMR
image/vnd.fujixerox.edmics-mmr
VS
Silicon Graphics Image
image/x-rgb
SGI-RGB
A complete technical comparison of Fuji Xerox EDMICS-MMR and Silicon Graphics Image — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | EDMICS-MMR | SGI-RGB |
|---|---|---|
| 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)
Silicon Graphics Image
image/x-rgb
Extension
.rgb.sgi.rgba.bw.int.inta
Container
SGI Image Header (512 bytes)
Compression
Uncompressed / Run-Length Encoding (RLE)
Algorithm
NoneScanline RLE
Color Depth
8-bit (Per Channel), 16-bit (Per Channel)
Developed by
Silicon Graphics, Inc. (Paul Haeberli)
Released
1988
Magic Bytes
01 DA
Browser Support Comparison
| Browser | EDMICS-MMR | SGI-RGB |
|---|---|---|
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
SGI-RGB
SGI-RGB Strengths
- Supports 16-bit precision per channel and an embedded alpha channel, making it ideal for the demanding compositing workflows of 1990s cinema VFX
- The scanline-based RLE compression was exceptionally fast to decode on classic MIPS-based SGI workstations
- Features a straightforward 512-byte header, making it relatively easy to parse and write custom decoders in C or Python
Limitations
- Completely obsolete and unsupported in modern web environments
- Replaced entirely by TIFF, OpenEXR, and PNG in modern visual effects and 3D rendering pipelines
- Lacks support for modern color management via ICC profiles or advanced EXIF metadata
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
SGI-RGB
Use SGI-RGB when…
- Legacy 3D Animation and VFX Textures
- Silicon Graphics IRIX Workstation Archival
- 1990s Medical Imaging