Image MIME Reference
DXF
Drawing Exchange Format
image/vnd.dxf
VS
JPEG 2000 Image (HEIF Container)
image/hej2k
HEJ2K
A complete technical comparison of Drawing Exchange Format and JPEG 2000 Image (HEIF Container) — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | DXF | HEJ2K |
|---|---|---|
| Transparency (Alpha) | Yes | Yes |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | Yes |
| HDR Support | ✕ No | Yes |
| EXIF Metadata | ✕ No | Yes |
| ICC Color Profile | ✕ No | Yes |
Drawing Exchange Format
image/vnd.dxf
Extension
.dxf
Container
Text / Binary Container
Compression
Uncompressed (ASCII) / Uncompressed (Binary)
Algorithm
None
Color Depth
Vector (Indexed AutoCAD Colors / True Color)
Developed by
Autodesk
Released
1982
Magic Bytes
30 0D 0A 53 45 43 54 49 4F 4E (ASCII) / 41 75 74 6F 43 41 44 20 42 69 6E 61 72 79 20 44 58 46 0D 0A 1A 00 (Binary)
JPEG 2000 Image (HEIF Container)
image/hej2k
Extension
.hej2
Container
HEIF / ISOBMFF (ISO/IEC 15444-16)
Compression
Lossy / Lossless
Algorithm
JPEG 2000HTJ2K
Color Depth
8-bit, 10-bit, 12-bit, 16-bit
Developed by
ISO/IEC JTC 1 / ITU-T
Released
2019
Magic Bytes
XX XX XX XX 66 74 79 70 6A 32 6B 69
Browser Support Comparison
| Browser | DXF | HEJ2K |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
DXF
DXF Strengths
- Universally supported by almost every CAD program, 3D modeler, and vector graphics editor in existence
- ASCII structure is human-readable and can be parsed or generated programmatically with relative ease
- The de facto standard for sending 2D cutting paths to CNC routers, plasma cutters, and laser engravers
Limitations
- ASCII DXF files can be enormously large and inefficient compared to binary DWG files
- The format relies heavily on legacy AutoCAD data structures, making complex 3D entity parsing extremely difficult for third-party developers
- Lacks native web browser rendering capabilities
HEJ2K
HEJ2K Strengths
- Brings the extensive capabilities of the HEIF container (like EXIF/XMP, thumbnails, and depth maps) to JPEG 2000
- Supports mathematically lossless compression via wavelet transformation
- High scalability and progressive decoding out of the box
Limitations
- Extremely limited software support outside of niche industries
- Zero native compatibility with web browsers
- High computational complexity compared to simpler formats like JPEG or PNG
When to choose which format
DXF
Use DXF when…
- Cross-Platform CAD Data Exchange
- CNC Machining and Laser Cutting Paths
- PCB Design Outlines
- Architectural 2D Layouts
HEJ2K
Use HEJ2K when…
- Medical Imaging
- Geospatial Data
- Scientific Archiving