speex - Add echo-cancelling option to speexdsp plugin

Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/doc/speexdsp.txt b/doc/speexdsp.txt
index 875fc19a581ebb0348d980ff76a7d90d6e86b84e..5b5e5a018a2bb2c74c318f876dafc99f30b4bbd9 100644 (file)
--- a/doc/speexdsp.txt
+++ b/doc/speexdsp.txt
@@ -12,7 +12,7 @@ using libspeex DSP API.  You can use the plugin with the plugin type
 
 Then record like
 
-       % arecord -fdat -c1 -Dplug:speex foo.wav
+       % arecord -fdat -c1 -Dplug:my_pcm foo.wav
 
 so that you'll get 48kHz mono stream with the denoising effect.
 
@@ -44,6 +44,15 @@ The following parameters can be set optionally:
 
   A boolean value to enable/disable dereverb function.  Default is no.
 
+* echo
+
+  A boolean value to enable/disable echo-cancellation function.
+  Default is no.
+
+* filter_length
+
+  Number of samples of echo to cancel.  As default it's 256.
+
 For example, you can enable agc like
 
        pcm.my_pcm {

diff --git a/speex/pcm_speex.c b/speex/pcm_speex.c
index 7bb921393b275f49c9bcd715b7863eac563c55b4..757a400e5b1bbd3512d31ffef7e7f6fde3854403 100644 (file)
--- a/speex/pcm_speex.c
+++ b/speex/pcm_speex.c
@@ -1,5 +1,5 @@
 /*
- * Speex preprocess plugin
+ * Speex DSP plugin
  *
  * Copyright (c) 2009 by Takashi Iwai <tiwai@suse.de>
  *
@@ -21,12 +21,15 @@
 #include <alsa/asoundlib.h>
 #include <alsa/pcm_external.h>
 #include <speex/speex_preprocess.h>
+#include <speex/speex_echo.h>
 
-/* preprocessing parameters */
+/* DSP parameters */
 struct spx_parms {
        int frames;
        int denoise;
        int agc;
+       int echo;
+       int filter_length;
        float agc_level;
        int dereverb;
        float dereverb_decay;
@@ -38,7 +41,9 @@ typedef struct {
        struct spx_parms parms;
        /* instance and intermedate buffer */
        SpeexPreprocessState *state;
+       SpeexEchoState *echo_state;
        short *buf;
+       short *outbuf;
        /* running states */
        unsigned int filled;
        unsigned int processed;
@@ -64,6 +69,18 @@ spx_transfer(snd_pcm_extplug_t *ext,
        short *src = area_addr(src_areas, src_offset);
        short *dst = area_addr(dst_areas, dst_offset);
        unsigned int count = size;
+       short *databuf;
+
+       if (!spx->state && !spx->echo_state) {
+               /* no DSP processing */
+               memcpy(dst, src, count * 2);
+               return size;
+       }
+
+       if (spx->echo_state)
+               databuf = spx->outbuf;
+       else
+               databuf = spx->buf;
 
        while (count > 0) {
                unsigned int chunk;
@@ -72,14 +89,20 @@ spx_transfer(snd_pcm_extplug_t *ext,
                else
                        chunk = count;
                if (spx->processed)
-                       memcpy(dst, spx->buf + spx->filled, chunk * 2);
+                       memcpy(dst, databuf + spx->filled, chunk * 2);
                else
                        memset(dst, 0, chunk * 2);
                dst += chunk;
                memcpy(spx->buf + spx->filled, src, chunk * 2);
                spx->filled += chunk;
                if (spx->filled == spx->parms.frames) {
-                       speex_preprocess_run(spx->state, spx->buf);
+                       if (spx->echo_state)
+                               speex_echo_capture(spx->echo_state, spx->buf,
+                                                  spx->outbuf);
+                       if (spx->state)
+                               speex_preprocess_run(spx->state, databuf);
+                       if (spx->echo_state)
+                               speex_echo_playback(spx->echo_state, databuf);
                        spx->processed = 1;
                        spx->filled = 0;
                }
@@ -94,6 +117,9 @@ static int spx_init(snd_pcm_extplug_t *ext)
 {
        snd_pcm_speex_t *spx = (snd_pcm_speex_t *)ext;
 
+       spx->filled = 0;
+       spx->processed = 0;
+
        if (!spx->buf) {
                spx->buf = malloc(spx->parms.frames * 2);
                if (!spx->buf)
@@ -101,12 +127,43 @@ static int spx_init(snd_pcm_extplug_t *ext)
        }
        memset(spx->buf, 0, spx->parms.frames * 2);
 
-       if (spx->state)
+       if (!spx->outbuf) {
+               spx->outbuf = malloc(spx->parms.frames * 2);
+               if (!spx->outbuf)
+                       return -ENOMEM;
+       }
+       memset(spx->outbuf, 0, spx->parms.frames * 2);
+
+       if (spx->state) {
                speex_preprocess_state_destroy(spx->state);
+               spx->state = NULL;
+       }
+       if (spx->echo_state) {
+               speex_echo_state_destroy(spx->echo_state);
+               spx->echo_state = NULL;
+       }
+
+       if (spx->parms.echo) {
+               spx->echo_state = speex_echo_state_init(spx->parms.frames,
+                                               spx->parms.filter_length);
+               if (!spx->echo_state)
+                       return -EIO;
+               speex_echo_ctl(spx->echo_state, SPEEX_ECHO_SET_SAMPLING_RATE,
+                              &spx->ext.rate);
+       }
+
+       /* no preprocessor? */
+       if (!spx->parms.denoise && !spx->parms.agc && !spx->parms.dereverb)
+               return 0;
+
        spx->state = speex_preprocess_state_init(spx->parms.frames,
                                                 spx->ext.rate);
        if (!spx->state)
                return -EIO;
+       if (spx->echo_state)
+               speex_preprocess_ctl(spx->state,
+                                    SPEEX_PREPROCESS_SET_ECHO_STATE,
+                                    spx->echo_state);
 
        speex_preprocess_ctl(spx->state, SPEEX_PREPROCESS_SET_DENOISE,
                             &spx->parms.denoise);
@@ -120,18 +177,18 @@ static int spx_init(snd_pcm_extplug_t *ext)
                             &spx->parms.dereverb_decay);
        speex_preprocess_ctl(spx->state, SPEEX_PREPROCESS_SET_DEREVERB_LEVEL,
                             &spx->parms.dereverb_level);
-
-       spx->filled = 0;
-       spx->processed = 0;
        return 0;
 }
 
 static int spx_close(snd_pcm_extplug_t *ext)
 {
        snd_pcm_speex_t *spx = (snd_pcm_speex_t *)ext;
+       free(spx->outbuf);
        free(spx->buf);
        if (spx->state)
                speex_preprocess_state_destroy(spx->state);
+       if (spx->echo_state)
+               speex_echo_state_destroy(spx->echo_state);      
        return 0;
 }
 
@@ -205,6 +262,8 @@ SND_PCM_PLUGIN_DEFINE_FUNC(speex)
                .dereverb = 0,
                .dereverb_decay = 0,
                .dereverb_level = 0,
+               .echo = 0,
+               .filter_length = 256,
        };
 
        snd_config_for_each(i, next, conf) {
@@ -242,6 +301,13 @@ SND_PCM_PLUGIN_DEFINE_FUNC(speex)
                                     &parms.dereverb_level);
                if (err)
                        goto ok;
+               err = get_bool_parm(n, id, "echo", &parms.echo);
+               if (err)
+                       goto ok;
+               err = get_int_parm(n, id, "filter_length",
+                                  &parms.filter_length);
+               if (err)
+                       goto ok;        
                SNDERR("Unknown field %s", id);
                err = -EINVAL;
        ok:
@@ -259,7 +325,7 @@ SND_PCM_PLUGIN_DEFINE_FUNC(speex)
                return -ENOMEM;
 
        spx->ext.version = SND_PCM_EXTPLUG_VERSION;
-       spx->ext.name = "Speex Denoise Plugin";
+       spx->ext.name = "Speex DSP Plugin";
        spx->ext.callback = &speex_callback;
        spx->ext.private_data = spx;
        spx->parms = parms;