Image MIME Reference
Panasonic-RAW-(RW2)
Panasonic RAW Image
image/x-panasonic-raw
VS
WebP Image
image/webp
WebP
A complete technical comparison of Panasonic RAW Image and WebP Image — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
WebP wins on browser support
Feature Support
| Feature | Panasonic-RAW-(RW2) | WebP |
|---|---|---|
| Transparency (Alpha) | ✕ No | Yes |
| Animation Support | ✕ No | Yes |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | Yes | ✕ No |
| EXIF Metadata | Yes | Yes |
| ICC Color Profile | Yes | Yes |
Panasonic RAW Image
image/x-panasonic-raw
Extension
.raw.rw2
Container
TIFF-based (Proprietary)
Compression
Uncompressed / Panasonic Proprietary Lossless
Algorithm
NoneProprietary Lossless
Color Depth
12-bit (Per Channel), 14-bit (Per Channel), 16-bit (Per Channel - High-res mode)
Developed by
Panasonic Corporation
Released
2004
Magic Bytes
Older RAW: 49 49 2A 00 | Newer RW2: 49 49 55 00
WebP Image
image/webp
Extension
.webp
Container
RIFF
Compression
Lossy / Lossless
Algorithm
VP8VP8L
Color Depth
8-bit
Developed by
Google
Released
2010
Magic Bytes
52 49 46 46 XX XX XX XX 57 45 42 50
Browser Support Comparison
| Browser | Panasonic-RAW-(RW2) | WebP |
|---|---|---|
Chrome
|
✕ |
✓ 32+
|
Firefox
|
✕ |
✓ 65+
|
Safari
|
✕ |
✓ 14+
|
Edge
|
✕ |
✓ 18+
|
IE (Legacy)
|
✕ | ✕ |
Panasonic-RAW-(RW2)
Panasonic-RAW-(RW2) Strengths
- Retains maximum sensor data, allowing significant recovery of highlights and shadows compared to in-camera JPEGs
- Modern RW2 files embed proprietary lens correction profiles (distortion, vignetting, chromatic aberration) that raw converters can automatically apply
- The unique 'IIU' signature on RW2 files makes programmatic identification extremely reliable compared to other TIFF-spoofing raw formats
Limitations
- Proprietary format requires continuous updates to third-party processing engines whenever Panasonic releases a new Lumix camera
- Produces very large file sizes, particularly when using Panasonic's High-Resolution multi-shot modes
- Cannot be directly embedded into web pages or used in standard HTML/CSS contexts
WebP
WebP Strengths
- Superior lossy compression — 25–35% smaller than JPEG at equivalent quality
- Supports both animation and full alpha transparency
- Lossless mode available with smaller file sizes than PNG
Limitations
- Slower encoding than JPEG, especially for lossless
- Not supported in Internet Explorer or very old browsers
When to choose which format
Panasonic-RAW-(RW2)
Use Panasonic-RAW-(RW2) when…
- Professional Digital Photography
- Non-destructive Image Post-Processing
- High Dynamic Range (HDR) Lumix Archival
WebP
Use WebP when…
- Websites
- Ecommerce
- Mobile Apps
- CMS Images