feat(audio): AEC NLMS adaptatif (mode aec 2)

components/audio_router/audio_router.c

@@ -49,12 +49,49 @@ static TaskHandle_t         s_task      = NULL;
 static volatile int s_play_gain = 8;   /* downlink : PCM mobile -> ecouteur */
 static volatile int s_mic_gain  = 12;  /* uplink   : micro -> mobile (filtre) */
 static volatile bool s_mic_filter = true;  /* passe-bande voix sur le micro */
-static volatile bool s_aec_on     = true;  /* suppression d'echo (mic ducking) */
+/* Mode anti-echo : 0=off, 1=suppression (ducking), 2=NLMS adaptatif. */
+static volatile int  s_aec_mode = 1;
 
 /* Enveloppe du signal downlink (ce qu'on joue dans l'ecouteur) = reference
  * d'echo, mise a jour par la lecture SCO, lue par la capture micro. */
 static volatile float s_dl_env = 0.0f;
 
+/* --- AEC NLMS (mode 2) --- */
+#define AEC_L 128                     /* longueur du filtre (8 ms @ 16k) */
+static float s_aec_w[AEC_L];          /* coeffs du filtre adaptatif */
+static float s_aec_xh[AEC_L];         /* historique de la reference (circulaire) */
+static int   s_aec_xi = 0;
+static volatile float s_aec_mu   = 0.30f;  /* pas d'adaptation NLMS */
+static volatile int   s_aec_delay = 320;   /* retard de boucle (samples) — reglable */
+static RingbufHandle_t s_aec_ref_rb = NULL;  /* reference (downlink) -> AEC */
+
+static float aec_nlms_step(float d, float x)
+{
+    s_aec_xh[s_aec_xi] = x;
+    float y = 0.0f, norm = 1e-3f;
+    int idx = s_aec_xi;
+    for (int k = 0; k < AEC_L; k++) {
+        float xv = s_aec_xh[idx];
+        y += s_aec_w[k] * xv;
+        norm += xv * xv;
+        idx = (idx - 1) & (AEC_L - 1);
+    }
+    float e = d - y;
+    /* Double-parole : si le micro depasse nettement l'echo estime -> voix
+     * proche -> on GELE l'adaptation (sinon le filtre diverge). */
+    float ad = d < 0 ? -d : d, ay = y < 0 ? -y : y;
+    if (ad < 2.0f * ay + 200.0f) {
+        float mu = s_aec_mu / norm;
+        idx = s_aec_xi;
+        for (int k = 0; k < AEC_L; k++) {
+            s_aec_w[k] += mu * e * s_aec_xh[idx];
+            idx = (idx - 1) & (AEC_L - 1);
+        }
+    }
+    s_aec_xi = (s_aec_xi + 1) & (AEC_L - 1);
+    return e;
+}
+
 static inline int16_t sat16(int32_t v)
 {
     if (v > 32767) return 32767;
@@ -117,10 +154,13 @@ void audio_router_load_gains(void)
     if (nvs_get_i32(h, "gspk", &v) == ESP_OK) s_play_gain  = (int)v;
     if (nvs_get_i32(h, "gmic", &v) == ESP_OK) s_mic_gain   = (int)v;
     if (nvs_get_i32(h, "filt", &v) == ESP_OK) s_mic_filter = (v != 0);
-    if (nvs_get_i32(h, "aec",  &v) == ESP_OK) s_aec_on     = (v != 0);
+    if (nvs_get_i32(h, "aec",  &v) == ESP_OK) s_aec_mode  = (int)v;
+    if (nvs_get_i32(h, "aecd", &v) == ESP_OK) s_aec_delay = (int)v;
+    if (nvs_get_i32(h, "aecmu",&v) == ESP_OK) s_aec_mu    = (float)v / 100.0f;
     nvs_close(h);
-    ESP_LOGI(TAG, "gains NVS: gspk=%d gmic=%d filt=%d aec=%d",
+    ESP_LOGI(TAG, "gains NVS: gspk=%d gmic=%d filt=%d aec=%d aecd=%d aecmu=%.2f",
-             s_play_gain, s_mic_gain, (int)s_mic_filter, (int)s_aec_on);
+             s_play_gain, s_mic_gain, (int)s_mic_filter, s_aec_mode,
+             s_aec_delay, s_aec_mu);
 }
 
 void audio_router_set_play_gain(int g)
@@ -135,10 +175,22 @@ void audio_router_set_mic_filter(bool on)
 {
     s_mic_filter = on; ar_nvs_set_i32("filt", on ? 1 : 0);
 }
-void audio_router_set_aec(bool on)
+void audio_router_set_aec(int mode)   /* 0=off 1=suppress 2=NLMS */
 {
-    s_aec_on = on; ar_nvs_set_i32("aec", on ? 1 : 0);
+    if (mode < 0 || mode > 2) return;
+    s_aec_mode = mode; ar_nvs_set_i32("aec", mode);
 }
+void audio_router_set_aec_delay(int samples)
+{
+    if (samples < 0 || samples > 4000) return;
+    s_aec_delay = samples; ar_nvs_set_i32("aecd", samples);
+}
+void audio_router_set_aec_mu(int mu_pct)  /* mu en % (ex. 30 -> 0.30) */
+{
+    if (mu_pct < 1 || mu_pct > 100) return;
+    s_aec_mu = (float)mu_pct / 100.0f; ar_nvs_set_i32("aecmu", mu_pct);
+}
+int audio_router_get_aec(void) { return s_aec_mode; }
 int audio_router_get_play_gain(void) { return s_play_gain; }
 int audio_router_get_mic_gain(void)  { return s_mic_gain; }
 
@@ -197,6 +249,13 @@ static void tone_task(void *a)
                 if ((float)dl_peak > env) env = (float)dl_peak;
                 s_dl_env = env;
 
+                /* Reference AEC : pousser le signal downlink joue (pre-gain),
+                 * draine 1:1 par la capture micro -> alignement reference/micro. */
+                if (s_aec_mode == 2 && s_aec_ref_rb) {
+                    xRingbufferSend(s_aec_ref_rb, sco_acc,
+                                    (size_t)target * sizeof(int16_t), 0);
+                }
+
                 /* Frame complete : mono -> stereo (CVSD double pour 8k->16k) */
                 int frames = 0;
                 for (int i = 0; i < target && frames < FRAME; i++) {
@@ -308,11 +367,27 @@ static void sco_mic_task(void *a)
         int n = hal_i2s_capture_read_frame(mono, FRAME, &e);
         if (n <= 0) { vTaskDelay(pdMS_TO_TICKS(5)); continue; }
         s_dbg_cap++;
-        /* 1) Filtre passe-bande voix (HP 300 Hz + LP 3400 Hz) + pic micro. */
+
+        /* 0) NLMS (mode 2) : recupere la frame de reference (downlink joue,
+         * alignee par le ring + le retard) et annule l'echo sur le micro brut. */
+        static float refbuf[FRAME];
+        if (s_aec_mode == 2 && s_aec_ref_rb) {
+            size_t got = 0;
+            int16_t *rp = (int16_t *)xRingbufferReceiveUpTo(s_aec_ref_rb, &got,
+                              pdMS_TO_TICKS(25), (size_t)n * sizeof(int16_t));
+            int rn = rp ? (int)(got / sizeof(int16_t)) : 0;
+            for (int i = 0; i < n; i++) refbuf[i] = (i < rn) ? (float)rp[i] : 0.0f;
+            if (rp) vRingbufferReturnItem(s_aec_ref_rb, rp);
+        }
+
+        /* 1) (NLMS) + filtre passe-bande voix (HP 300 Hz + LP 3400 Hz) + pic. */
         static float fbuf[FRAME];
         float ne_peak = 0.0f;
         for (int i = 0; i < n; i++) {
             float x = (float)mono[i];
+            if (s_aec_mode == 2) {
+                x = aec_nlms_step(x, refbuf[i]);   /* annulation d'echo */
+            }
             if (s_mic_filter) {
                 x = biquad_run(&s_hp, x);
                 x = biquad_run(&s_lp, x);
@@ -321,13 +396,12 @@ static void sco_mic_task(void *a)
             float a = x < 0 ? -x : x;
             if (a > ne_peak) ne_peak = a;
         }
-        /* 2) Suppression d'echo : si le correspondant parle (downlink actif) et
+        /* 2) Suppression residuelle (modes 1 et 2) : duck le micro quand le
-         * que le micro n'est pas dominant (=echo, pas de voix proche), on duck
+         * correspondant parle et que le micro n'est pas dominant. */
-         * le micro. Attaque rapide, relachement lent (commutation de voix). */
         static float s_supp = 1.0f;
         float target = 1.0f;
-        if (s_aec_on && s_dl_env > 800.0f && ne_peak < s_dl_env * 0.6f) {
+        if (s_aec_mode >= 1 && s_dl_env > 800.0f && ne_peak < s_dl_env * 0.6f) {
-            target = 0.12f;   /* atténuation forte de l'echo */
+            target = (s_aec_mode == 2) ? 0.4f : 0.12f;  /* plus doux avec NLMS */
         }
         if (target < s_supp) s_supp += (target - s_supp) * 0.6f;   /* attaque rapide */
         else                 s_supp += (target - s_supp) * 0.05f;  /* relâchement lent */
@@ -356,6 +430,20 @@ void audio_router_sco_begin(bool msbc)
     mic_dsp_init();   /* (re)calcule les coeffs du filtre + reset l'etat */
     if (!s_sco_play_rb) s_sco_play_rb = xRingbufferCreate(SCO_RB_SIZE, RINGBUF_TYPE_BYTEBUF);
     if (!s_sco_cap_rb)  s_sco_cap_rb  = xRingbufferCreate(SCO_RB_SIZE, RINGBUF_TYPE_BYTEBUF);
+    /* Ring de reference AEC + reset du filtre NLMS + preremplissage du retard. */
+    if (!s_aec_ref_rb)  s_aec_ref_rb  = xRingbufferCreate(8192, RINGBUF_TYPE_BYTEBUF);
+    memset(s_aec_w, 0, sizeof(s_aec_w));
+    memset(s_aec_xh, 0, sizeof(s_aec_xh));
+    s_aec_xi = 0;
+    if (s_aec_ref_rb) {
+        static int16_t zeros[512] = {0};
+        int d = s_aec_delay;
+        while (d > 0) {
+            int chunk = d > 512 ? 512 : d;
+            xRingbufferSend(s_aec_ref_rb, zeros, (size_t)chunk * sizeof(int16_t), 0);
+            d -= chunk;
+        }
+    }
     hal_i2s_capture_begin();
     hal_audio_pa_set(true);
     audio_router_init();          /* s'assure que tone_task existe */

components/audio_router/include/audio_router.h

@@ -14,7 +14,10 @@ void audio_router_init(void);
 void audio_router_set_play_gain(int g);   /* downlink : ecouteur */
 void audio_router_set_mic_gain(int g);    /* uplink   : micro -> mobile */
 void audio_router_set_mic_filter(bool on);
-void audio_router_set_aec(bool on);       /* suppression d'echo (mic ducking) */
+void audio_router_set_aec(int mode);       /* 0=off 1=suppression 2=NLMS */
+void audio_router_set_aec_delay(int samples);
+void audio_router_set_aec_mu(int mu_pct);
+int  audio_router_get_aec(void);
 int  audio_router_get_play_gain(void);
 int  audio_router_get_mic_gain(void);
 

components/cli/cli.c

@@ -27,15 +27,21 @@ static void handle(char *l)
         int on = atoi(l + 4);
         audio_router_set_mic_filter(on != 0);
         ESP_LOGI(TAG, "filtre micro = %s", on ? "ON" : "OFF");
+    } else if (strncmp(l, "aecd", 4) == 0) {
+        audio_router_set_aec_delay(atoi(l + 4));
+        ESP_LOGI(TAG, "AEC retard = %d samples", atoi(l + 4));
+    } else if (strncmp(l, "aecmu", 5) == 0) {
+        audio_router_set_aec_mu(atoi(l + 5));
+        ESP_LOGI(TAG, "AEC mu = %d%%", atoi(l + 5));
     } else if (strncmp(l, "aec", 3) == 0) {
-        int on = atoi(l + 3);
+        audio_router_set_aec(atoi(l + 3));
-        audio_router_set_aec(on != 0);
+        ESP_LOGI(TAG, "anti-echo = %d (0=off 1=suppress 2=NLMS)", audio_router_get_aec());
-        ESP_LOGI(TAG, "annulation d'echo = %s", on ? "ON" : "OFF");
     } else if (strncmp(l, "status", 6) == 0) {
-        ESP_LOGI(TAG, "gspk=%d gmic=%d",
+        ESP_LOGI(TAG, "gspk=%d gmic=%d aec=%d",
-                 audio_router_get_play_gain(), audio_router_get_mic_gain());
+                 audio_router_get_play_gain(), audio_router_get_mic_gain(),
+                 audio_router_get_aec());
     } else {
-        ESP_LOGI(TAG, "cmds: gmic N | gspk N | filt 0/1 | aec 0/1 | status");
+        ESP_LOGI(TAG, "cmds: gmic N|gspk N|filt 0/1|aec 0/1/2|aecd N|aecmu N|status");
     }
 }