Image MIME Reference
JPS
JPEG Stereo Image
image/x-jps
VS
Valve Texture Format
image/vnd.valve.source.texture
VTF
A complete technical comparison of JPEG Stereo Image and Valve Texture Format — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
JPS wins on browser support
Feature Support
| Feature | JPS | VTF |
|---|---|---|
| Transparency (Alpha) | ✕ No | Yes |
| Animation Support | ✕ No | Yes |
| Progressive Loading | Yes | ✕ No |
| HDR Support | ✕ No | Yes |
| EXIF Metadata | Yes | ✕ No |
| ICC Color Profile | Yes | ✕ No |
JPEG Stereo Image
image/x-jps
Extension
.jps
Container
JPEG (JFIF/Exif)
Compression
Lossy (JPEG/DCT)
Algorithm
JPEG (Discrete Cosine Transform)
Color Depth
8-bit (Grayscale), 24-bit (RGB)
Developed by
Stereoscopic Community (Unofficial Standard)
Released
1990
Magic Bytes
FF D8 FF
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 | JPS | VTF |
|---|---|---|
Chrome
|
✓ 1
|
✕ |
Firefox
|
✓ 1
|
✕ |
Safari
|
✓ 1
|
✕ |
Edge
|
✓ 12
|
✕ |
IE (Legacy)
|
✓
|
✕ |
JPS
JPS Strengths
- 100% backward compatible with every standard 2D image viewer and web browser (which simply display the two halves side-by-side)
- Inherits JPEG's excellent lossy compression, resulting in small file sizes ideal for web transmission
- Extremely easy to generate programmatically by simply stitching two JPEG images side-by-side onto a wider canvas
Limitations
- Lack of a dedicated metadata standard means viewing software has to guess whether the layout is 'cross-eyed' (right eye left, left eye right) or 'parallel' (left eye left, right eye right), occasionally causing inverted depth
- Suffers from JPEG compression artifacts, which can break the stereoscopic illusion if compression noise differs between the left and right eyes
- Superseded in consumer electronics by the MPO (Multi-Picture Object) format, which stacks separate full-resolution JPEGs rather than squishing them side-by-side
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
JPS
Use JPS when…
- Stereoscopic 3D Photography
- Virtual Reality (VR) Image Galleries
- Cross-eye / Parallel Stereograms
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)