[Asterisk-video] mp4save, help saving other audio formats

[aj2r]

Hello all, with mp4_save we can save ulaw, alaw and amr-nb audio, but
generally softphones don't support amr-nb, and uncompressed formats
(ulaw, alaw) aren't the best choice to store audio. Could anybody help
me modifying app_mp4 to add support for (e.g.) GSM? 
-- 
Alberto José Rodríguez Rodríguez
Fundación I+D del Software Libre
Parque Tecnológico de Ciencias de la Salud
BIC Granada-CEEI
Avda. de la Innovación, 1
18100 Armilla (Granada)
Tlf. 958750457
ajrodriguez at fidesol.org
www.fidesol.org