mp4_amr_128_96_v68_12_a12.sdp
mp4_amr_128_96_v180_15_a12.sdp
mp4_amr_128_96_v250_20_a12.sdp
mp4_amr_128_96_v300_25_a12.sdp
mp4_amr_128_96_v370_30_a12.sdp
mp4_amr_vbr_128_96_v38_10_a12.sdp
mp4_amr_vbr_128_96_v108_15_a12.sdp