Image MIME Reference
AVCS
AVC Image Sequence (HEIF Container)
image/avcs
VS
Comverse Network Systems INF2 Image
image/vnd.cns.inf2
CNS-INF2
A complete technical comparison of AVC Image Sequence (HEIF Container) and Comverse Network Systems INF2 Image — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | AVCS | CNS-INF2 |
|---|---|---|
| Transparency (Alpha) | Yes | ✕ No |
| Animation Support | Yes | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | Yes | ✕ No |
| EXIF Metadata | Yes | ✕ No |
| ICC Color Profile | Yes | ✕ No |
AVC Image Sequence (HEIF Container)
image/avcs
Extension
.avcs.heifs
Container
HEIF / ISOBMFF (ISO/IEC 14496-12)
Compression
Lossy / Lossless
Algorithm
AVC (Advanced Video Coding / H.264)
Color Depth
8-bit, 10-bit, 12-bit
Developed by
Moving Picture Experts Group (MPEG) / ISO/IEC JTC 1
Released
2015
Magic Bytes
XX XX XX XX 66 74 79 70 61 76 63 73
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)
Browser Support Comparison
| Browser | AVCS | CNS-INF2 |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
AVCS
AVCS Strengths
- Efficiently stores bursts of images or animations utilizing inter-frame compression
- Leverages the highly compatible and widely hardware-accelerated AVC (H.264) codec
- Robust HEIF container supports extensive metadata, alpha channels, and depth maps
Limitations
- Zero native support in web browsers
- Largely superseded in efficiency by newer sequence formats like HEICS (HEVC) or Animated AVIF (AV1)
- Complicated container structure requires specialized parsing libraries
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
When to choose which format
AVCS
Use AVCS when…
- Burst Photography
- Short Animations
- Camera Capture
- Archival Storage
CNS-INF2
Use CNS-INF2 when…
- Legacy Telecom Infrastructure
- Historical Comverse Unified Messaging Systems
- Proprietary Server-to-Server Media Exchange