Compressed GIMP XCF Image

import gzip
import magic

# Identify the outer wrapper
file_type = magic.from_file('project.xcf.gz', mime=True)
print(f'Outer format: {file_type}') # Likely 'application/gzip'

# Validate the inner payload
with gzip.open('project.xcf.gz', 'rb') as f:
    inner_magic = f.read(9)
    is_xcf = inner_magic == b'gimp xcf '
    print(f'Contains valid XCF: {is_xcf}')

const fs = require('fs');
const zlib = require('zlib');

const stream = fs.createReadStream('project.xcf.gz');
const unzip = zlib.createGunzip();

stream.pipe(unzip).once('data', (chunk) => {
    const isXCF = chunk.toString('ascii', 0, 9) === 'gimp xcf ';
    console.log('Is compressed XCF:', isXCF);
    unzip.destroy();
    stream.destroy();
});

import (
    "compress/gzip"
    "os"
    "bytes"
)
// Open the file and pass it to gzip.NewReader
// Read the first 9 bytes of the uncompressed stream
// isXCF := bytes.Equal(uncompressedBuf[:9], []byte("gimp xcf "))

$mime = mime_content_type('project.xcf.gz');
echo $mime; // Standard PHP setups will return 'application/x-gzip'. You must use the zlib extension to read the internal payload.