pjsip迴音消除

pjsip迴音消除

1. pjmedia_echo_flag enum 初始化參數

• 算法位 掩碼： PJMEDIA_ECHO_ALGO_MASK = 15,

算法類型：
PJMEDIA_ECHO_DEFAULT = 0 默認也是speex
PJMEDIA_ECHO_SPEEX	= 1
PJMEDIA_ECHO_SIMPLE	= 2
PJMEDIA_ECHO_WEBRTC = 3
提取方式 (option & PJMEDIA_ECHO_ALGO_MASK);  //取最後字節

• 僅使用軟件實現

PJMEDIA_ECHO_USE_SW_ECHO = 64，

• 同時也使用噪音抑制

PJMEDIA_ECHO_USE_NOISE_SUPPRESSOR = 128， (0x80)

• 迴音消除的激烈模式

PJMEDIA_ECHO_AGGRESSIVENESS_MASK = 0xF00, //掩碼位
PJMEDIA_ECHO_AGGRESSIVENESS_DEFAULT = 0, 默認moderate
PJMEDIA_ECHO_AGGRESSIVENESS_CONSERVATIVE = 0x100,
PJMEDIA_ECHO_AGGRESSIVENESS_MODERATE = 0x200,
PJMEDIA_ECHO_AGGRESSIVENESS_AGGRESSIVE = 0x300,

2. pjmedia_echo_stat 統計信息

• median， Echo delay median value (in ms).
• std， Echo delay standard deviation (in ms).
• frac_delay， Fraction of poor delay. Value between 0 to 1.
• learning， Learning still in progress?
• duration，Learning duration (in ms).
• tail，Detected echo tail length (in ms).
• min_factor，Minimum scaling factor (in ms).
• avg_factor， Average scaling factor (in ms).
• buf_， Internal buffer.

3. 創建、重置、銷燬

• pjmedia_echo_create
• pjmedia_echo_create2
• pjmedia_echo_reset
• pjmedia_echo_destroy

4. 獲取統計信息

• pjmedia_echo_get_stat

5. 迴音消除處理邏輯

• pjmedia_echo_playback 送給喇叭之前先發給ec
• pjmedia_echo_capture 麥克風採集到數據先發給ec
• pjmedia_echo_cancel 進行迴音消除處理\噪音抑制， 得到結果