Image MIME Reference
AOL-ART
AOL ART Image
image/x-jg
VS
Canon Raw Version 2
image/x-canon-cr2
Canon-CR2
A complete technical comparison of AOL ART Image and Canon Raw Version 2 — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | AOL-ART | Canon-CR2 |
|---|---|---|
| Transparency (Alpha) | ✕ No | ✕ No |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | Yes | ✕ No |
| HDR Support | ✕ No | Yes |
| EXIF Metadata | ✕ No | Yes |
| ICC Color Profile | ✕ No | Yes |
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
Canon Raw Version 2
image/x-canon-cr2
Extension
.cr2
Container
TIFF
Compression
Lossless JPEG (ITU-T81)
Algorithm
Lossless JPEG (ITU-T81)
Color Depth
12-bit (Per Channel), 14-bit (Per Channel)
Developed by
Canon Inc.
Released
2004
Magic Bytes
49 49 2A 00 10 00 00 00 43 52 02 00
Browser Support Comparison
| Browser | AOL-ART | Canon-CR2 |
|---|---|---|
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✕ | ✕ |
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✕ | ✕ |
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✕ | ✕ |
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|
✕ | ✕ |
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✕ | ✕ |
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
Canon-CR2
Canon-CR2 Strengths
- Retains maximum sensor data, allowing extreme recovery of highlights and shadows that would be permanently lost in a JPEG
- White balance and color profiling are not 'baked in', meaning they can be completely altered in post-production without degrading the image
- Lossless compression ensures perfect pixel accuracy while reducing file size compared to fully uncompressed formats
Limitations
- Proprietary format means it requires constant updates to raw processing engines (like Adobe Camera Raw) every time Canon releases a new camera model
- Produces very large file sizes (often 20MB to 40MB per image depending on sensor resolution)
- Cannot be directly embedded into web pages or used in standard HTML/CSS contexts
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
Canon-CR2
Use Canon-CR2 when…
- Professional Digital Photography
- Non-destructive Image Post-Processing
- High Dynamic Range (HDR) Imaging Archival