Free webp to jpg
Image MIME Reference
PTI

PTI Image (Personal/Vanity Tree)

image/prs.pti
VS

Valve Texture Format

image/vnd.valve.source.texture
VTF

A complete technical comparison of PTI Image (Personal/Vanity Tree) and Valve Texture Format — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.

Equal browser support

Feature Support

Feature PTI VTF
Transparency (Alpha) ✕ No Yes
Animation Support ✕ No Yes
Progressive Loading ✕ No ✕ No
HDR Support ✕ No Yes
EXIF Metadata ✕ No ✕ No
ICC Color Profile ✕ No ✕ No
PTI Image (Personal/Vanity Tree)
image/prs.pti
Extension
.pti
Container Proprietary
Compression Unknown / Proprietary
Algorithm
Unknown
Color Depth Unknown
Developed by Jürn Laun
Released 1999
Magic Bytes
Unknown
Full PTI reference →
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
Full VTF reference →

Browser Support Comparison

Browser PTI VTF
Chrome Chrome
Firefox Firefox
Safari Safari
Edge Edge
IE IE (Legacy)
PTI

PTI Strengths

  • Provided a registered MIME type namespace for a specific application's proprietary image format without conflicting with standard web types
Limitations
  • Completely undocumented and unsupported in modern ecosystems
  • Zero web browser compatibility
  • Falls into the 'vanity' tree, making it irrelevant for standard cross-platform data exchange
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

PTI
Use PTI when…
  • Legacy Application Specific Workflows
  • Proprietary Image Storage
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)
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