Image MIME Reference
Canon-CRW
Canon Raw Format
image/x-canon-crw
VS
Digital Entertainment Content Ecosystem (DECE) Graphic
image/vnd.dece.graphic
DECE-Graphic
A complete technical comparison of Canon Raw Format 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 | Canon-CRW | DECE-Graphic |
|---|---|---|
| Transparency (Alpha) | ✕ No | Yes |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | Yes | ✕ No |
| EXIF Metadata | Yes | ✕ No |
| ICC Color Profile | ✕ No | ✕ No |
Canon Raw Format
image/x-canon-crw
Extension
.crw
Container
CIFF (Camera Image File Format)
Compression
Lossless JPEG (ITU-T81)
Algorithm
Lossless JPEG
Color Depth
10-bit (Per Channel), 12-bit (Per Channel)
Developed by
Canon Inc.
Released
1998
Magic Bytes
49 49 1A 00 00 00 (Header) / 48 45 41 50 43 43 44 52 (HEAPCCDR signature near end)
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 | Canon-CRW | DECE-Graphic |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
Canon-CRW
Canon-CRW Strengths
- Preserves original raw sensor data from foundational early digital SLR cameras, allowing for modern noise reduction and demosaicing algorithms to extract better images than software could in 2003
- Files are remarkably small (often 6-8 MB) compared to modern 40MB+ raw files due to the lower megapixel count of early sensors
Limitations
- Completely obsolete and utilizes the idiosyncratic CIFF structure rather than the modern, standardized TIFF/EP structure
- Cannot be natively viewed in web browsers or standard operating system image viewers without specialized codecs
- Less robust metadata support compared to modern CR2 or CR3 formats
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
Canon-CRW
Use Canon-CRW when…
- Historical Digital Photography (2000-2004)
- Non-destructive Image Post-Processing
- Raw Imaging Archival
DECE-Graphic
Use DECE-Graphic when…
- UltraViolet Movie Cover Art
- Common File Format (CFF) Asset Manifests
- Legacy DRM Ecosystems