Valve Texture Format

import magic
# Libmagic usually accurately detects the 'VTF\0' header
print(magic.from_file('texture.vtf', mime=True)) # May output 'image/vnd.valve.source.texture' or generic 'application/octet-stream'

const fs = require('fs');
// Manually detecting the 'VTF\0' magic bytes
const buffer = Buffer.alloc(4);
const fd = fs.openSync('texture.vtf', 'r');
fs.readSync(fd, buffer, 0, 4, 0);
fs.closeSync(fd);
const isVTF = buffer[0] === 0x56 && buffer[1] === 0x54 && buffer[2] === 0x46 && buffer[3] === 0x00;
console.log('Is VTF Texture:', isVTF);

import (
    "bytes"
    "net/http"
)
// http.DetectContentType will not recognize VTF natively. Check the byte prefix directly.
// isVTF := bytes.HasPrefix(buf, []byte{0x56, 0x54, 0x46, 0x00})

$mime = mime_content_type('texture.vtf');
echo $mime; // Standard setups will often resolve this to 'application/octet-stream' without custom magic file definitions.