Image MIME Reference
DECE-Graphic
Digital Entertainment Content Ecosystem (DECE) Graphic
image/vnd.dece.graphic
VS
Progressive JPEG (Legacy IE Alias)
image/pjpeg
PJPEG
A complete technical comparison of Digital Entertainment Content Ecosystem (DECE) Graphic and Progressive JPEG (Legacy IE Alias) — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
PJPEG wins on browser support
Feature Support
| Feature | DECE-Graphic | PJPEG |
|---|---|---|
| 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 |
Digital Entertainment Content Ecosystem (DECE) Graphic
image/vnd.dece.graphic
Extension
.jpg.png.uvi
Container
Standard JPEG/PNG within DECE CFF structures
Compression
Lossy (JPEG) / Lossless (PNG)
Algorithm
DCT (JPEG)DEFLATE (PNG)
Color Depth
8-bit (RGB), 24-bit (RGB)
Developed by
Digital Entertainment Content Ecosystem (DECE) LLC
Released
2011
Magic Bytes
FF D8 FF (If JPEG) / 89 50 4E 47 (If PNG)
Progressive JPEG (Legacy IE Alias)
image/pjpeg
Extension
.jpeg.jpg.pjpeg.pjp.jfif
Container
JPEG (ISO/IEC 10918-1)
Compression
Lossy (DCT)
Algorithm
Discrete Cosine Transform (DCT)
Color Depth
8-bit, 12-bit
Developed by
Joint Photographic Experts Group / Microsoft (Alias)
Released
1992
Magic Bytes
FF D8 FF E0 (JFIF) / FF D8 FF E1 (Exif)
Browser Support Comparison
| Browser | DECE-Graphic | PJPEG |
|---|---|---|
Chrome
|
✕ |
✓ All
|
Firefox
|
✕ |
✓ All
|
Safari
|
✕ |
✓ All
|
Edge
|
✕ |
✓ All
|
IE (Legacy)
|
✕ |
✓
|
DECE-Graphic
DECE-Graphic Strengths
- Allowed the UltraViolet DRM ecosystem to easily distinguish structural UI/cover graphic assets from actual encrypted video tracks in a Common File Format container
Limitations
- Completely obsolete since the 2019 shutdown of UltraViolet
- Unnecessary abstraction, as the underlying files were just standard JPEGs or PNGs
- Causes modern strict MIME-type validators to fail if they rely on the Content-Type header
PJPEG
PJPEG Strengths
- Progressive JPEGs (which this MIME type attempted to describe) provide excellent perceived loading speeds on slow connections by rendering a low-resolution preview first
- Files sent with this MIME type are fully backwards compatible with any standard JPEG decoder
Limitations
- It is a non-standard MIME type that violates IANA specifications
- Causes strict file upload validation scripts to fail if not explicitly whitelisted or mapped
- Creates unnecessary confusion, as the official image/jpeg MIME type already fully encompasses progressive encoding
When to choose which format
DECE-Graphic
Use DECE-Graphic when…
- UltraViolet Movie Cover Art
- Common File Format (CFF) Asset Manifests
- Legacy DRM Ecosystems
PJPEG
Use PJPEG when…
- Legacy Internet Explorer File Uploads
- Progressive Image Rendering (Historical context)