[asterisk-dev] Corrupted recordings

[James Cloos]

I've been made aware of an instance of asterisk which makes heave use of
res_monitor, records to gsm files, and often sees corruption in the gsm
files.

The corrupt blobs are very regular.  If you split an affected gsm file
into 33-octet chunks, all of the non-gsm chunks in each such blob are
identical.

The suspicion is that the caller transferred the call.  My suspicion,
therefore, is that the corruption is ulaw rining packets.

Is it possible that the code which generates ringing sounds bypasses
res_monitor's codec translation?


The problem with the corruption is that libgsm's decode routine
truncates the output once it sees a non-gsm 33-octet packet.
Ie one which does not start with the nybble 0xD.  So all of the
data after that is lost.

-JimC
-- 
James Cloos <cloos at jhcloos.com>         OpenPGP: 0x997A9F17ED7DAEA6