Image MIME Reference
DGN
MicroStation Design File
image/x-vnd.dgn
VS
JPEG Stereo Image
image/x-jps
JPS
A complete technical comparison of MicroStation Design File and JPEG Stereo Image — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
JPS wins on browser support
Feature Support
| Feature | DGN | JPS |
|---|---|---|
| Transparency (Alpha) | Yes | ✕ No |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | Yes |
| HDR Support | ✕ No | ✕ No |
| EXIF Metadata | ✕ No | Yes |
| ICC Color Profile | ✕ No | Yes |
MicroStation Design File
image/x-vnd.dgn
Extension
.dgn
Container
Microsoft OLE Compound File (V8) / IGDS (V7)
Compression
Uncompressed / OLE Structured Storage
Algorithm
None
Color Depth
Indexed Color (V7), 24-bit True Color (V8)
Developed by
Intergraph (Originally) / Bentley Systems (Currently)
Released
1980
Magic Bytes
D0 CF 11 E0 A1 B1 1A E1 (For V8 DGN)
JPEG Stereo Image
image/x-jps
Extension
.jps
Container
JPEG (JFIF/Exif)
Compression
Lossy (JPEG/DCT)
Algorithm
JPEG (Discrete Cosine Transform)
Color Depth
8-bit (Grayscale), 24-bit (RGB)
Developed by
Stereoscopic Community (Unofficial Standard)
Released
1990
Magic Bytes
FF D8 FF
Browser Support Comparison
| Browser | DGN | JPS |
|---|---|---|
Chrome
|
✕ |
✓ 1
|
Firefox
|
✕ |
✓ 1
|
Safari
|
✕ |
✓ 1
|
Edge
|
✕ |
✓ 12
|
IE (Legacy)
|
✕ |
✓
|
DGN
DGN Strengths
- Exceptionally robust at handling massive, coordinate-heavy infrastructure models that would frequently crash older versions of competing CAD software
- Deeply entrenched as the absolute standard format for many global departments of transportation and civil engineering firms
- V8 architecture supports boundless design plane coordinates, eliminating the physical scaling limitations of V7
Limitations
- Deeply proprietary format requiring complex third-party libraries (like the ODA SDK) to parse or write programmatically outside of the Bentley ecosystem
- V8's reliance on the archaic Microsoft OLE Compound File container makes file introspection cumbersome
- Cannot be rendered natively in web browsers without converting to WebGL/Canvas formats or SVG
JPS
JPS Strengths
- 100% backward compatible with every standard 2D image viewer and web browser (which simply display the two halves side-by-side)
- Inherits JPEG's excellent lossy compression, resulting in small file sizes ideal for web transmission
- Extremely easy to generate programmatically by simply stitching two JPEG images side-by-side onto a wider canvas
Limitations
- Lack of a dedicated metadata standard means viewing software has to guess whether the layout is 'cross-eyed' (right eye left, left eye right) or 'parallel' (left eye left, right eye right), occasionally causing inverted depth
- Suffers from JPEG compression artifacts, which can break the stereoscopic illusion if compression noise differs between the left and right eyes
- Superseded in consumer electronics by the MPO (Multi-Picture Object) format, which stacks separate full-resolution JPEGs rather than squishing them side-by-side
When to choose which format
DGN
Use DGN when…
- Civil Engineering and Plant Design
- Large-scale Architecture and Construction (AEC)
- 2D/3D Infrastructure Modeling
JPS
Use JPS when…
- Stereoscopic 3D Photography
- Virtual Reality (VR) Image Galleries
- Cross-eye / Parallel Stereograms