Image MIME Reference
CNS-INF2
Comverse Network Systems INF2 Image
image/vnd.cns.inf2
VS
Portable Anymap
image/x-portable-anymap
PNM
A complete technical comparison of Comverse Network Systems INF2 Image and Portable Anymap — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | CNS-INF2 | PNM |
|---|---|---|
| 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 |
Comverse Network Systems INF2 Image
image/vnd.cns.inf2
Extension
.inf2
Container
Proprietary Comverse Container
Compression
Proprietary
Algorithm
Unknown (Proprietary Telecom Encoding)
Color Depth
Unknown
Developed by
Comverse Network Systems (Ann McLaughlin)
Released
1999
Magic Bytes
Unknown (Proprietary)
Portable Anymap
image/x-portable-anymap
Extension
.pnm
Container
Netpbm
Compression
Uncompressed
Algorithm
None
Color Depth
1-bit (PBM), 8-bit to 16-bit (PGM), 24-bit to 48-bit (PPM)
Developed by
Jef Poskanzer (Netpbm Project)
Released
1988
Magic Bytes
50 31, 50 32, 50 33, 50 34, 50 35, or 50 36
Browser Support Comparison
| Browser | CNS-INF2 | PNM |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
CNS-INF2
CNS-INF2 Strengths
- Historically allowed Comverse to standardize media transmission internally across their global telecom messaging platforms
Limitations
- Completely obsolete and non-functional outside of decommissioned telecom infrastructure
- Undocumented, closed-source binary structure
- Zero support in modern image processing libraries like ImageMagick, libvips, or FFmpeg
PNM
PNM Strengths
- Unparalleled simplicity: parsers and writers for PNM files can be written from scratch in C or Python in just a few minutes without relying on external libraries
- Serves as an excellent foundational teaching tool for computer science students learning about image arrays and raster graphics
- Flawlessly pipes through Unix command-line utilities for robust automated image processing (via the Netpbm suite)
Limitations
- Zero compression natively results in astronomical file sizes, making it entirely impractical for web delivery or consumer storage
- No support for standard metadata formats like EXIF, XMP, or ICC color profiles
- No native alpha channel support in the classic PNM specification (though the newer PAM format 'P7' addresses this)
When to choose which format
CNS-INF2
Use CNS-INF2 when…
- Legacy Telecom Infrastructure
- Historical Comverse Unified Messaging Systems
- Proprietary Server-to-Server Media Exchange
PNM
Use PNM when…
- Unix/Linux Command-Line Image Processing (Netpbm suite)
- Academic Computer Vision Research
- Intermediary Format for Image Format Conversion