Convert hex to ascii characters

Question

Is it possible to represent a sequence of hex characters (0-9A-F) with a sequence of 0-9a-zA-Z characters, so the the result sequence is smaller and can be decoded?

Answer 1

You mean want to convert a string of hex digits into actual hex values?

$hex_string = "A1B2C3D4F5"; // 10 chars/bytes
$packed_string = pack('H*', $hex_string); // 0xA1B2C3D4F5 // 5 chars/bytes.