Image MIME Reference
DXF
Drawing Exchange Format
image/vnd.dxf
VS
HEVC Image Sequence (HEIF Container)
image/heic-sequence
HEIC-Sequence
A complete technical comparison of Drawing Exchange Format and HEVC Image Sequence (HEIF Container) — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
HEIC-Sequence wins on browser support
Feature Support
| Feature | DXF | HEIC-Sequence |
|---|---|---|
| Transparency (Alpha) | Yes | Yes |
| Animation Support | ✕ No | Yes |
| Progressive Loading | ✕ No | ✕ No |
| 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)
HEVC Image Sequence (HEIF Container)
image/heic-sequence
Extension
.heics.heic
Container
HEIF / ISOBMFF (ISO/IEC 14496-12)
Compression
Lossy / Lossless
Algorithm
HEVC (H.265)
Color Depth
8-bit, 10-bit, 12-bit, 16-bit
Developed by
Moving Picture Experts Group (MPEG) / Apple
Released
2017
Magic Bytes
XX XX XX XX 66 74 79 70 68 65 76 63
Browser Support Comparison
| Browser | DXF | HEIC-Sequence |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ |
✓ 11+
|
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
HEIC-Sequence
HEIC-Sequence Strengths
- Incredibly efficient storage for bursts and short animations compared to GIF or motion JPEG
- Supports 16-bit color, HDR, and alpha channel transparency across all frames
- Shares frame data blocks, meaning the base image and animation data are heavily optimized for space
Limitations
- Zero support in web browsers outside the Apple ecosystem (Chrome, Firefox, Edge do not support it)
- Heavily encumbered by HEVC patent pools, hindering open-source adoption
- Complex container structure makes parsing and decoding difficult without specialized libraries
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
HEIC-Sequence
Use HEIC-Sequence when…
- Apple Live Photos
- Burst Photography
- High-Quality Animations
- Cinemagraphs