echo-cancel: Move speex preprocessing out of the main module

I initially included put the Speex preprocessing assuming that we'd want
to use the digital gain control and noise suppression from Speex for all
echo cancelling implementations. In practice, we're probably going to
get entire implementations all processing in one package (WebRTC, custom
modules from various vendors, etc.).

This moves out this preprocessing and related knobs into the speex
implementation, which serves to clean out all implementation-specific
details from the module-echo-cancel core.

3 files changed, 117 insertions, 98 deletions

diff --git a/src/modules/echo-cancel/echo-cancel.h b/src/modules/echo-cancel/echo-cancel.h
index b2cf61db..9f679807 100644
--- a/src/modules/echo-cancel/echo-cancel.h
+++ b/src/modules/echo-cancel/echo-cancel.h
@@ -43,6 +43,7 @@ struct pa_echo_canceller_params {
     union {
         struct {
             SpeexEchoState *state;
+            SpeexPreprocessState *pp_state;
         } speex;
         struct {
             uint32_t blocksize;
@@ -67,13 +68,6 @@ struct pa_echo_canceller {
     void        (*done)                 (pa_echo_canceller *ec);
 
     pa_echo_canceller_params params;
-
-    pa_bool_t agc;
-    pa_bool_t denoise;
-    pa_bool_t echo_suppress;
-    int32_t echo_suppress_attenuation;
-    int32_t echo_suppress_attenuation_active;
-    SpeexPreprocessState *pp_state;
 };
 
 /* Speex canceller functions */
diff --git a/src/modules/echo-cancel/module-echo-cancel.c b/src/modules/echo-cancel/module-echo-cancel.c
index 04e5b028..fe39baa2 100644
--- a/src/modules/echo-cancel/module-echo-cancel.c
+++ b/src/modules/echo-cancel/module-echo-cancel.c
@@ -72,11 +72,6 @@ PA_MODULE_USAGE(
           "channel_map=<channel map> "
           "aec_method=<implementation to use> "
           "aec_args=<parameters for the AEC engine> "
-          "agc=<perform automagic gain control?> "
-          "denoise=<apply denoising?> "
-          "echo_suppress=<perform residual echo suppression? (only with the speex canceller)> "
-          "echo_suppress_attenuation=<dB value of residual echo attenuation> "
-          "echo_suppress_attenuation_active=<dB value of residual echo attenuation when near end is active> "
           "save_aec=<save AEC data in /tmp> "
           "autoloaded=<set if this module is being loaded automatically> "
         ));
@@ -108,10 +103,6 @@ static const pa_echo_canceller ec_table[] = {
 #define DEFAULT_RATE 32000
 #define DEFAULT_CHANNELS 1
 #define DEFAULT_ADJUST_TIME_USEC (1*PA_USEC_PER_SEC)
-#define DEFAULT_AGC_ENABLED TRUE
-#define DEFAULT_DENOISE_ENABLED TRUE
-#define DEFAULT_ECHO_SUPPRESS_ENABLED TRUE
-#define DEFAULT_ECHO_SUPPRESS_ATTENUATION 0
 #define DEFAULT_SAVE_AEC 0
 #define DEFAULT_AUTOLOADED FALSE
 
@@ -218,11 +209,6 @@ static const char* const valid_modargs[] = {
     "channel_map",
     "aec_method",
     "aec_args",
-    "agc",
-    "denoise",
-    "echo_suppress",
-    "echo_suppress_attenuation",
-    "echo_suppress_attenuation_active",
     "save_aec",
     "autoloaded",
     NULL
@@ -727,10 +713,6 @@ static void source_output_push_cb(pa_source_output *o, const pa_memchunk *chunk)
                 /* perform echo cancellation */
                 u->ec->run(u->ec, rdata, pdata, cdata);
 
-                /* preprecessor is run after AEC. This is not a mistake! */
-                if (u->ec->pp_state)
-                    speex_preprocess_run(u->ec->pp_state, (spx_int16_t *) cdata);
-
                 if (u->save_aec) {
                     if (u->canceled_file)
                         fwrite(cdata, 1, u->blocksize, u->canceled_file);
@@ -1407,48 +1389,6 @@ int pa__init(pa_module*m) {
     else
         u->adjust_time = DEFAULT_ADJUST_TIME_USEC;
 
-    u->ec->agc = DEFAULT_AGC_ENABLED;
-    if (pa_modargs_get_value_boolean(ma, "agc", &u->ec->agc) < 0) {
-        pa_log("Failed to parse agc value");
-        goto fail;
-    }
-
-    u->ec->denoise = DEFAULT_DENOISE_ENABLED;
-    if (pa_modargs_get_value_boolean(ma, "denoise", &u->ec->denoise) < 0) {
-        pa_log("Failed to parse denoise value");
-        goto fail;
-    }
-
-    u->ec->echo_suppress = DEFAULT_ECHO_SUPPRESS_ENABLED;
-    if (pa_modargs_get_value_boolean(ma, "echo_suppress", &u->ec->echo_suppress) < 0) {
-        pa_log("Failed to parse echo_suppress value");
-        goto fail;
-    }
-    if (u->ec->echo_suppress && ec_method != PA_ECHO_CANCELLER_SPEEX) {
-        pa_log("Echo suppression is only useful with the speex canceller");
-        goto fail;
-    }
-
-    u->ec->echo_suppress_attenuation = DEFAULT_ECHO_SUPPRESS_ATTENUATION;
-    if (pa_modargs_get_value_s32(ma, "echo_suppress_attenuation", &u->ec->echo_suppress_attenuation) < 0) {
-        pa_log("Failed to parse echo_suppress_attenuation value");
-        goto fail;
-    }
-    if (u->ec->echo_suppress_attenuation > 0) {
-        pa_log("echo_suppress_attenuation should be a negative dB value");
-        goto fail;
-    }
-
-    u->ec->echo_suppress_attenuation_active = DEFAULT_ECHO_SUPPRESS_ATTENUATION;
-    if (pa_modargs_get_value_s32(ma, "echo_suppress_attenuation_active", &u->ec->echo_suppress_attenuation_active) < 0) {
-        pa_log("Failed to parse echo_suppress_attenuation_active value");
-        goto fail;
-    }
-    if (u->ec->echo_suppress_attenuation_active > 0) {
-        pa_log("echo_suppress_attenuation_active should be a negative dB value");
-        goto fail;
-    }
-
     u->save_aec = DEFAULT_SAVE_AEC;
     if (pa_modargs_get_value_u32(ma, "save_aec", &u->save_aec) < 0) {
         pa_log("Failed to parse save_aec value");
@@ -1470,31 +1410,6 @@ int pa__init(pa_module*m) {
         }
     }
 
-    if (u->ec->agc || u->ec->denoise || u->ec->echo_suppress) {
-        spx_int32_t tmp;
-
-        if (source_ss.channels != 1) {
-            pa_log("AGC, denoising and echo suppression only work with channels=1");
-            goto fail;
-        }
-
-        u->ec->pp_state = speex_preprocess_state_init(u->blocksize / pa_frame_size(&source_ss), source_ss.rate);
-
-        tmp = u->ec->agc;
-        speex_preprocess_ctl(u->ec->pp_state, SPEEX_PREPROCESS_SET_AGC, &tmp);
-        tmp = u->ec->denoise;
-        speex_preprocess_ctl(u->ec->pp_state, SPEEX_PREPROCESS_SET_DENOISE, &tmp);
-        if (u->ec->echo_suppress) {
-            if (u->ec->echo_suppress_attenuation)
-                speex_preprocess_ctl(u->ec->pp_state, SPEEX_PREPROCESS_SET_ECHO_SUPPRESS, &u->ec->echo_suppress_attenuation);
-            if (u->ec->echo_suppress_attenuation_active) {
-                speex_preprocess_ctl(u->ec->pp_state, SPEEX_PREPROCESS_SET_ECHO_SUPPRESS_ACTIVE,
-                                     &u->ec->echo_suppress_attenuation_active);
-            }
-            speex_preprocess_ctl(u->ec->pp_state, SPEEX_PREPROCESS_SET_ECHO_STATE, u->ec->params.priv.speex.state);
-        }
-    }
-
     /* Create source */
     pa_source_new_data_init(&source_data);
     source_data.driver = __FILE__;
@@ -1765,9 +1680,6 @@ void pa__done(pa_module*m) {
     if (u->sink_memblockq)
         pa_memblockq_free(u->sink_memblockq);
 
-    if (u->ec->pp_state)
-        speex_preprocess_state_destroy(u->ec->pp_state);
-
     if (u->ec) {
         if (u->ec->done)
             u->ec->done(u->ec);
diff --git a/src/modules/echo-cancel/speex.c b/src/modules/echo-cancel/speex.c
index 72c52680..d6331fc5 100644
--- a/src/modules/echo-cancel/speex.c
+++ b/src/modules/echo-cancel/speex.c
@@ -25,6 +25,7 @@
 #include <config.h>
 #endif
 
+#include <pulsecore/core-util.h>
 #include <pulsecore/modargs.h>
 #include "echo-cancel.h"
 
@@ -32,10 +33,19 @@
 #define DEFAULT_FRAME_SIZE_MS 20
 /* should be between 100-500 ms */
 #define DEFAULT_FILTER_SIZE_MS 200
+#define DEFAULT_AGC_ENABLED TRUE
+#define DEFAULT_DENOISE_ENABLED TRUE
+#define DEFAULT_ECHO_SUPPRESS_ENABLED TRUE
+#define DEFAULT_ECHO_SUPPRESS_ATTENUATION 0
 
 static const char* const valid_modargs[] = {
     "frame_size_ms",
     "filter_size_ms",
+    "agc",
+    "denoise",
+    "echo_suppress",
+    "echo_suppress_attenuation",
+    "echo_suppress_attenuation_active",
     NULL
 };
 
@@ -48,6 +58,93 @@ static void pa_speex_ec_fixate_spec(pa_sample_spec *source_ss, pa_channel_map *s
     *sink_map = *source_map;
 }
 
+static pa_bool_t pa_speex_ec_preprocessor_init(pa_echo_canceller *ec, pa_sample_spec *source_ss, uint32_t blocksize, pa_modargs *ma) {
+    pa_bool_t agc;
+    pa_bool_t denoise;
+    pa_bool_t echo_suppress;
+    int32_t echo_suppress_attenuation;
+    int32_t echo_suppress_attenuation_active;
+
+    agc = DEFAULT_AGC_ENABLED;
+    if (pa_modargs_get_value_boolean(ma, "agc", &agc) < 0) {
+        pa_log("Failed to parse agc value");
+        goto fail;
+    }
+
+    denoise = DEFAULT_DENOISE_ENABLED;
+    if (pa_modargs_get_value_boolean(ma, "denoise", &denoise) < 0) {
+        pa_log("Failed to parse denoise value");
+        goto fail;
+    }
+
+    echo_suppress = DEFAULT_ECHO_SUPPRESS_ENABLED;
+    if (pa_modargs_get_value_boolean(ma, "echo_suppress", &echo_suppress) < 0) {
+        pa_log("Failed to parse echo_suppress value");
+        goto fail;
+    }
+
+    echo_suppress_attenuation = DEFAULT_ECHO_SUPPRESS_ATTENUATION;
+    if (pa_modargs_get_value_s32(ma, "echo_suppress_attenuation", &echo_suppress_attenuation) < 0) {
+        pa_log("Failed to parse echo_suppress_attenuation value");
+        goto fail;
+    }
+    if (echo_suppress_attenuation > 0) {
+        pa_log("echo_suppress_attenuation should be a negative dB value");
+        goto fail;
+    }
+
+    echo_suppress_attenuation_active = DEFAULT_ECHO_SUPPRESS_ATTENUATION;
+    if (pa_modargs_get_value_s32(ma, "echo_suppress_attenuation_active", &echo_suppress_attenuation_active) < 0) {
+        pa_log("Failed to parse echo_suppress_attenuation_active value");
+        goto fail;
+    }
+    if (echo_suppress_attenuation_active > 0) {
+        pa_log("echo_suppress_attenuation_active should be a negative dB value");
+        goto fail;
+    }
+
+    if (agc || denoise || echo_suppress) {
+        spx_int32_t tmp;
+
+        if (source_ss->channels != 1) {
+            pa_log("AGC, denoising and echo suppression only work with channels=1");
+            goto fail;
+        }
+
+        ec->params.priv.speex.pp_state = speex_preprocess_state_init(blocksize / pa_frame_size(source_ss), source_ss->rate);
+
+        tmp = agc;
+        speex_preprocess_ctl(ec->params.priv.speex.pp_state, SPEEX_PREPROCESS_SET_AGC, &tmp);
+
+        tmp = denoise;
+        speex_preprocess_ctl(ec->params.priv.speex.pp_state, SPEEX_PREPROCESS_SET_DENOISE, &tmp);
+
+        if (echo_suppress) {
+            if (echo_suppress_attenuation)
+                speex_preprocess_ctl(ec->params.priv.speex.pp_state, SPEEX_PREPROCESS_SET_ECHO_SUPPRESS,
+                                     &echo_suppress_attenuation);
+
+            if (echo_suppress_attenuation_active) {
+                speex_preprocess_ctl(ec->params.priv.speex.pp_state, SPEEX_PREPROCESS_SET_ECHO_SUPPRESS_ACTIVE,
+                                     &echo_suppress_attenuation_active);
+            }
+
+            speex_preprocess_ctl(ec->params.priv.speex.pp_state, SPEEX_PREPROCESS_SET_ECHO_STATE,
+                                 ec->params.priv.speex.state);
+        }
+
+        pa_log_info("Loaded speex preprocessor with params: agc=%s, denoise=%s, echo_suppress=%s", pa_yes_no(agc),
+                    pa_yes_no(denoise), pa_yes_no(echo_suppress));
+    } else
+        pa_log_info("All preprocessing options are disabled");
+
+    return TRUE;
+
+fail:
+    return FALSE;
+}
+
+
 pa_bool_t pa_speex_ec_init(pa_core *c, pa_echo_canceller *ec,
                            pa_sample_spec *source_ss, pa_channel_map *source_map,
                            pa_sample_spec *sink_ss, pa_channel_map *sink_map,
@@ -95,21 +192,37 @@ pa_bool_t pa_speex_ec_init(pa_core *c, pa_echo_canceller *ec,
 
     speex_echo_ctl(ec->params.priv.speex.state, SPEEX_ECHO_SET_SAMPLING_RATE, &rate);
 
+    if (!pa_speex_ec_preprocessor_init(ec, source_ss, *blocksize, ma))
+        goto fail;
+
     pa_modargs_free(ma);
     return TRUE;
 
 fail:
     if (ma)
         pa_modargs_free(ma);
+    if (ec->params.priv.speex.state)
+        speex_preprocess_state_destroy(ec->params.priv.speex.pp_state);
     return FALSE;
 }
 
 void pa_speex_ec_run(pa_echo_canceller *ec, const uint8_t *rec, const uint8_t *play, uint8_t *out) {
-    speex_echo_cancellation(ec->params.priv.speex.state, (const spx_int16_t *) rec, (const spx_int16_t *) play, (spx_int16_t *) out);
+    speex_echo_cancellation(ec->params.priv.speex.state, (const spx_int16_t *) rec, (const spx_int16_t *) play,
+                            (spx_int16_t *) out);
+
+    /* preprecessor is run after AEC. This is not a mistake! */
+    if (ec->params.priv.speex.pp_state)
+        speex_preprocess_run(ec->params.priv.speex.pp_state, (spx_int16_t *) out);
 }
 
 void pa_speex_ec_done(pa_echo_canceller *ec) {
-    if (ec->params.priv.speex.state)
+    if (ec->params.priv.speex.pp_state) {
+        speex_preprocess_state_destroy(ec->params.priv.speex.pp_state);
+        ec->params.priv.speex.pp_state = NULL;
+    }
+
+    if (ec->params.priv.speex.state) {
         speex_echo_state_destroy(ec->params.priv.speex.state);
-    ec->params.priv.speex.state = NULL;
+        ec->params.priv.speex.state = NULL;
+    }
 }