Image MIME Reference
SVF
Simple Vector Format
image/vnd.svf
VS
X Window Dump (Legacy MIME Alias)
image/x-xwindowdump
XWD
A complete technical comparison of Simple Vector Format and X Window Dump (Legacy MIME Alias) — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | SVF | XWD |
|---|---|---|
| Transparency (Alpha) | Yes | Yes |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | ✕ No | ✕ No |
| EXIF Metadata | ✕ No | ✕ No |
| ICC Color Profile | ✕ No | ✕ No |
Simple Vector Format
image/vnd.svf
Extension
.svf
Container
Custom Binary/Text (Legacy) or ZIP (Autodesk Forge)
Compression
Uncompressed / Deflate (in modern Autodesk SVF implementations)
Algorithm
None
Color Depth
Vector Data (Not Applicable)
Developed by
SoftSource & NCSA (National Center for Supercomputing Applications)
Released
1995
Magic Bytes
Unknown (SoftSource SVF)
X Window Dump (Legacy MIME Alias)
image/x-xwindowdump
Extension
.xwd.wd
Container
XWDHeader / XWDFileHeader Structure
Compression
Uncompressed
Algorithm
None
Color Depth
8-bit (Indexed), 16-bit (High Color), 24-bit (True Color), 32-bit (True Color with Alpha/Padding)
Developed by
MIT / X Consortium (X Window System)
Released
1987
Magic Bytes
00 00 00 64 (Typically indicates a 100-byte header size followed by version)
Browser Support Comparison
| Browser | SVF | XWD |
|---|---|---|
|
|
✕ | ✕ |
|
|
✕ | ✕ |
|
|
✕ | ✕ |
|
|
✕ | ✕ |
|
|
✕ | ✕ |
SVF
SVF Strengths
- Acted as a crucial pioneering stepping-stone in proving that scalable, zoomable vector graphics were viable and necessary for the World Wide Web
Limitations
- Completely obsolete and unsupported by modern web standards
- Required end-users to install bulky, proprietary browser plugins
- Causes significant developer confusion today due to Autodesk adopting the exact same acronym and file extension for a completely different technology
XWD
XWD Strengths
- Provides an exact, raw pixel dump directly from the X11 display server memory without compression overhead
- Extremely fast for Unix environments to generate during low-level graphical debugging
Limitations
- Completely uncompressed, resulting in large, bloated file sizes
- Zero support in web browsers or modern desktop environments without specialized graphics translation tools
- Verbose legacy MIME strings like 'image/x-xwindowdump' require backend normalization in modern applications
When to choose which format
SVF
Use SVF when…
- Historical Web-based CAD Viewers (1990s)
- Legacy 2D Vector Archival
- Autodesk Platform Services (Forge) Model Translation (Name Collision)
XWD
Use XWD when…
- X Window System (X11) Display Debugging and Screenshots
- Legacy Unix/Linux System Administration