Image MIME Reference
3DS
Autodesk 3D Studio
image/x-3ds
VS
T.38 Fax over IP (FoIP)
image/t38
T.38
A complete technical comparison of Autodesk 3D Studio and T.38 Fax over IP (FoIP) — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | 3DS | T.38 |
|---|---|---|
| Transparency (Alpha) | Yes | ✕ No |
| Animation Support | Yes | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | ✕ No | ✕ No |
| EXIF Metadata | ✕ No | ✕ No |
| ICC Color Profile | ✕ No | ✕ No |
Autodesk 3D Studio
image/x-3ds
Extension
.3ds
Container
Binary Chunk System
Compression
Uncompressed Binary (Chunk-based)
Algorithm
None
Color Depth
Not Applicable (Stores 3D geometry and material RGB definitions)
Developed by
Autodesk (The Yost Group)
Released
1990
Magic Bytes
4D 4D
T.38 Fax over IP (FoIP)
image/t38
Extension
.t38
Container
UDPTL or TCP (Network Transport)
Compression
Lossless (MH, MR, MMR / T.4, T.6)
Algorithm
MH (Modified Huffman)MR (Modified Read)MMR (Modified Modified Read)
Color Depth
1-bit (Monochrome B&W)
Developed by
ITU-T (International Telecommunication Union)
Released
1998
Magic Bytes
None (Network Stream)
Browser Support Comparison
| Browser | 3DS | T.38 |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
3DS
3DS Strengths
- Nearly universal support; practically every 3D modeling application created in the last 30 years can read and write 3DS files
- Extremely simple, well-documented binary structure that is trivial to parse for custom rendering engines
Limitations
- Hard limit of 65,536 vertices and polygons per mesh due to 16-bit addressing
- Enforces archaic 8.3 MS-DOS filename length restrictions for all linked texture files
- Lacks support for modern 3D concepts like skeletal animation (rigging), normal mapping, and physically based rendering (PBR)
T.38
T.38 Strengths
- Designed specifically to overcome the timing and packet-loss issues that plague traditional fax over standard VoIP audio codecs (like G.711)
- Reduces bandwidth requirements by transmitting fax protocol data rather than uncompressed audio tones
- Universally supported by enterprise SIP trunks and Session Border Controllers (SBCs) for FoIP
Limitations
- Not an actual image file format, causing confusion due to its 'image/' MIME classification
- Extremely complex to implement correctly over lossy UDP networks (relies on UDPTL redundancy mechanisms)
- Zero support in web browsers or standard image viewing software
When to choose which format
3DS
Use 3DS when…
- Legacy 3D Model Exchange
- Low-Poly Game Assets
- Historical 3D Archival and Academic Use
T.38
Use T.38 when…
- Fax over IP (FoIP) Transmissions
- SIP/SDP Media Negotiation
- VoIP Gateways and PBX Systems
- Enterprise Fax Servers