AMR is an audio data compression scheme especially suited for speech coding. It has found large
use in GSM (and derivative, like UMTS) mobile phone systems. It's also the standard speech codec choosed
by 3GPP.
Sample hexdump
Here's a sample hexdump of an .AMR file's header (first 256 bytes):
Marked in yellow are the patterns used by
TrID to identify an AMR file.
Check the MiniDumper tool to obtain an hexdump from a file in an easy way!