Image MIME Reference
BTIF
Bank Telecommunications Image Format
image/prs.btif
VS
CMU Window Manager Raster
image/x-cmu-raster
CMU-Raster
A complete technical comparison of Bank Telecommunications Image Format and CMU Window Manager Raster — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | BTIF | CMU-Raster |
|---|---|---|
| Transparency (Alpha) | ✕ No | ✕ No |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | ✕ No | ✕ No |
| EXIF Metadata | ✕ No | ✕ No |
| ICC Color Profile | ✕ No | ✕ No |
Bank Telecommunications Image Format
image/prs.btif
Extension
.btif.btf
Container
Proprietary Check Image Container
Compression
Lossy (JPEG-based) / Lossless (TIFF-based)
Algorithm
JPEGTIFF-variant
Color Depth
1-bit (B&W), 8-bit (Grayscale)
Developed by
NationsBank (Bank of America) / Ben Simon
Released
1998
Magic Bytes
Unknown (Proprietary container)
CMU Window Manager Raster
image/x-cmu-raster
Extension
.ras
Container
CMU Window Manager Bitmap
Compression
Uncompressed
Algorithm
None
Color Depth
1-bit (Monochrome), 8-bit (Indexed/Grayscale)
Developed by
Carnegie Mellon University (CMU)
Released
1980s
Magic Bytes
F1 00 40 BB
Browser Support Comparison
| Browser | BTIF | CMU-Raster |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
BTIF
BTIF Strengths
- Allowed early digital archiving and web-based transmission of cleared bank checks
- Encapsulated both image data and ASCII transaction metadata in a single file
Limitations
- Completely proprietary and obsolete format
- Lacks native support in modern operating systems and image viewers
- Requires legacy plugins or specialized bio-format readers (like ImageC) to decode
CMU-Raster
CMU-Raster Strengths
- Incredibly simple, uncompressed binary structure that was easy for early, memory-constrained UNIX workstations to parse and render
Limitations
- Completely obsolete and unsupported outside of niche historical command-line tools like Netpbm
- The shared '.ras' file extension causes frequent file misidentification and system conflicts
- Lacks all modern imaging features, including metadata, compression, and alpha channel transparency
When to choose which format
BTIF
Use BTIF when…
- Bank Check Archiving (Legacy)
- Financial Transaction Records
CMU-Raster
Use CMU-Raster when…
- Historical UNIX / Andrew Project Archival
- Legacy Academic Computing Research