hex values!!

[map200uk]

hi, yes im trying now to read aac encoded files!

 

i have read up on it and 36 address location is start of moov atom, which all udta meta belongs to and the previous 4 vytes before 36 hold the length of the entire moov atm (so we read that in is the plan)

 

however the length is in hex i.e. A4 2D is used for 42029 - im not too sure how to get php to get these 4 bytes and then convert the ascii to its hex equivalent?

 

 

[Barand]

<?php
$txt = 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxA42Dyyyyyyyyyyyyyyyyyyyyyyyyyyyyy';
$hex = substr($txt,31,4);
echo hexdec($hex);  
?>

[map200uk]

i tried that, but the thing is

 

the file is read and the out chr is output?

 

i need to get the hex value from the file then convert that to dec?

 

or am i missing something?

 

ta