Image MIME Reference
AOL-ART
AOL ART Image
image/x-jg
VS
Digital Entertainment Content Ecosystem (DECE) Graphic
image/vnd.dece.graphic
DECE-Graphic
A complete technical comparison of AOL ART Image and Digital Entertainment Content Ecosystem (DECE) Graphic — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | AOL-ART | DECE-Graphic |
|---|---|---|
| Transparency (Alpha) | ✕ No | Yes |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | Yes | ✕ No |
| HDR Support | ✕ No | ✕ No |
| EXIF Metadata | ✕ No | ✕ No |
| ICC Color Profile | ✕ No | ✕ No |
AOL ART Image
image/x-jg
Extension
.art
Container
Johnson-Grace Proprietary
Compression
Proprietary Wavelet (Photos) / Proprietary Palette-based (Graphics)
Algorithm
Wavelet (similar to early JPEG 2000 concepts)Lossy DCT
Color Depth
8-bit (Indexed), 24-bit (RGB)
Developed by
Johnson-Grace Company (Acquired by AOL)
Released
1994
Magic Bytes
4A 47 03 00 or 4A 47 04 00
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)
Browser Support Comparison
| Browser | AOL-ART | DECE-Graphic |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
AOL-ART
AOL-ART Strengths
- Historically provided massive file size reductions (up to 3x smaller than JPEGs of the era) and highly optimized progressive rendering for 14.4k modems
- Enabled faster web browsing on the AOL network during the early days of the commercial internet
Limitations
- Completely proprietary, heavily patent-encumbered, and never officially reverse-engineered for the open-source community
- On-the-fly proxy compression ruined the visual fidelity of many 1990s websites for AOL users
- Virtually impossible to open on modern operating systems without installing niche, legacy image viewers
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
When to choose which format
AOL-ART
Use AOL-ART when…
- Historical AOL Dial-up Web Browsing
- Legacy America Online Client Assets
- 1990s Internet Archival
DECE-Graphic
Use DECE-Graphic when…
- UltraViolet Movie Cover Art
- Common File Format (CFF) Asset Manifests
- Legacy DRM Ecosystems