Image MIME Reference
QTIF
QuickTime Image Format
image/x-quicktime
VS
Valve Texture Format
image/vnd.valve.source.texture
VTF
A complete technical comparison of QuickTime Image Format and Valve Texture Format — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | QTIF | VTF |
|---|---|---|
| Transparency (Alpha) | Yes | Yes |
| Animation Support | ✕ No | Yes |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | ✕ No | Yes |
| EXIF Metadata | ✕ No | ✕ No |
| ICC Color Profile | ✕ No | ✕ No |
QuickTime Image Format
image/x-quicktime
Extension
.qtif.qti.qif
Container
QuickTime Atom Container
Compression
Varies (JPEG, SMC, Apple Video, Cinepak, Uncompressed)
Algorithm
QuickTime Image Compression Manager (ICM) Codecs
Color Depth
1-bit to 32-bit (Varies depending on the enclosed codec)
Developed by
Apple Computer, Inc.
Released
1991
Magic Bytes
Varies (Typically begins with a 32-bit size integer followed by 69 64 73 63 ('idsc'))
Valve Texture Format
image/vnd.valve.source.texture
Extension
.vtf
Container
Valve Texture Format Header
Compression
DXTC (DXT1, DXT3, DXT5) / Uncompressed (BGRA8888, RGB888, etc.)
Algorithm
DXT1-DXT5None
Color Depth
8-bit, 24-bit (RGB), 32-bit (RGBA), 16-bit Floating Point (HDR)
Developed by
Valve Corporation
Released
2004
Magic Bytes
56 54 46 00
Browser Support Comparison
| Browser | QTIF | VTF |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
QTIF
QTIF Strengths
- Extremely flexible architecture allowing it to encapsulate virtually any image compression algorithm available on the host machine
- Supported 32-bit images with alpha channels (transparency) long before PNG became an established standard
Limitations
- Fundamentally tied to Apple's deprecated QuickTime architecture, rendering the files almost entirely unreadable on modern systems without specialized legacy software or FFmpeg
- The 'wrapper' nature of the format means that even if a parser can read the QTIF container, it may fail to render the image if it lacks the specific proprietary codec (like Apple SMC) used to compress the pixel data
- Zero native support in modern web browsers
VTF
VTF Strengths
- Extremely fast loading within the Source Engine because the block-compressed data goes directly into the GPU's VRAM without CPU decompression overhead
- Bundles mipmaps, volumetric slices, cubemap faces, and animation frames entirely within a single file
- Openly documented by the Valve Developer Community, leading to a massive ecosystem of third-party modding tools
Limitations
- Strictly tied to the Source Engine ecosystem; entirely useless in standard web or print contexts
- No native support in standard image editors without hunting down and installing specialized plugins
- Block compression algorithms (DXT) are lossy and can cause visible artifacting, especially on normal maps or smooth gradients
When to choose which format
QTIF
Use QTIF when…
- Classic Mac OS Applications and Backgrounds
- QuickTime VR Panorama Textures
- 1990s CD-ROM Multimedia Assets
VTF
Use VTF when…
- Source Engine Game Textures
- Custom Maps and Modding (Garry's Mod, CS:GO)
- Animated In-Game Decals and Sprays
- Environment Cubemaps (Skyboxes)