Image MIME Reference
FreeHand
Macromedia FreeHand Document
image/x-freehand
VS
Sigma X3F RAW Image
image/x-sigma-x3f
Sigma-X3F
A complete technical comparison of Macromedia FreeHand Document and Sigma X3F RAW Image — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | FreeHand | Sigma-X3F |
|---|---|---|
| Transparency (Alpha) | Yes | ✕ No |
| Animation Support | Yes | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | ✕ No | Yes |
| EXIF Metadata | ✕ No | Yes |
| ICC Color Profile | Yes | Yes |
Macromedia FreeHand Document
image/x-freehand
Extension
.fh.fh4.fh5.fh7.fh8.fh9.fh10.fh11.ft11
Container
Proprietary Binary (Aldus Graphic Document)
Compression
Uncompressed / Deflate (in later versions)
Algorithm
NoneDeflate (Optional in later versions)
Color Depth
Vector Data (RGB/CMYK)
Developed by
Altsys / Aldus / Macromedia
Released
1988
Magic Bytes
41 47 44 31 to 41 47 44 34
Sigma X3F RAW Image
image/x-sigma-x3f
Extension
.x3f
Container
Foveon Proprietary Header
Compression
Uncompressed / Proprietary Lossless
Algorithm
NoneFoveon Proprietary Huffman-based
Color Depth
12-bit (Per Channel), 14-bit (Per Channel)
Developed by
Foveon, Inc. / Sigma Corporation
Released
2002
Magic Bytes
46 4F 56 62
Browser Support Comparison
| Browser | FreeHand | Sigma-X3F |
|---|---|---|
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FreeHand
FreeHand Strengths
- Historically one of the most powerful and intuitive vector editors on the market, praised for multi-page support long before Adobe Illustrator implemented it
- Files are generally compact and self-contained
Limitations
- Completely abandoned proprietary format; Adobe actively blocked native import in modern versions of Illustrator
- No support in modern web browsers; must be converted to SVG
- Versioning fragmentation means parsers must account for wildly different binary structures depending on the specific .fhX extension used
Sigma-X3F
Sigma-X3F Strengths
- Provides absolute per-pixel color accuracy without the interpolation artifacts or moiré patterns typical of Bayer-sensor RAW files
- Unique 'FOVb' magic byte signature prevents accidental misidentification by standard file sniffers, unlike many TIFF-based raw formats
- Incredible sharpness and detail resolution at the raw sensor level
Limitations
- Decoding is extremely computationally expensive and completely proprietary, meaning third-party software often struggles to match the color science of Sigma's own (famously slow) Photo Pro application
- Massive file sizes because it records three complete RGB channels for every single spatial pixel coordinate
- Zero support in web browsers or standard OS image viewers
When to choose which format
FreeHand
Use FreeHand when…
- Legacy Graphic Design Portfolios
- Historical Desktop Publishing Archival
- Old Corporate Logo Vectors
Sigma-X3F
Use Sigma-X3F when…
- Professional Digital Photography
- Sigma / Foveon High-Acuity Imaging
- Non-destructive RAW Post-Processing