JPEG XS Image Sequence (HEIF Container)

import magic
print(magic.from_file('sequence.jxss', mime=True)) # May default to generic 'image/heif' or 'application/octet-stream'

const FileType = require('file-type');
const type = await FileType.fromFile('sequence.jxss');
console.log(type?.mime); // Standard libraries will likely fail to identify the specific 'jxss' HEIF brand

import "net/http"
// Custom ISOBMFF box parsing is required to extract the 'jxss' brand from the ftyp box.

$mime = mime_content_type('sequence.jxss');
echo $mime; // Standard server configurations often map this to application/octet-stream