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G.723.1 is an audio codec for voice that compresses voice audio in 30 ms frames. An algorithmic look-ahead of 7.5 ms duration means that total algorithmic delay is 37.5 ms. Its official name is ''Dual rate speech coder for multimedia communications transmitting at 5.3 and 6.3 kbit/s''. Note that this is a completely different codec from G.723. There are two bit rates at which G.723.1 can operate: * 6.3 kbit/s (using 24 byte frames) using a MPC-MLQ algorithm (MOS 3.9) * 5.3 kbit/s (using 20 byte frames) using an ACELP algorithm (MOS 3.62) == Use == G.723.1 is mostly used in Voice over IP (VoIP) applications due to its low bandwidth requirement. Music or tones such as DTMF or fax tones cannot be transported reliably with this codec, and thus some other method such as G.711 or out-of-band methods should be used to transport these signals. The complexity of the algorithm is below 16 MIPS. 2.2 kilobytes of RAM is needed for codebooks. G.723.1 is a required audio codec in the H.324 ITU-T recommendation for H.324 terminals offering audio communication. In 3GPP 3G-324M specification support for G.723.1 is not mandatory, but recommended. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「G.723.1」の詳細全文を読む スポンサード リンク
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