source: mediastreamer2/src/speexec.c @ 1040:8e8716785083

/*
mediastreamer2 library - modular sound and video processing and streaming
Copyright (C) 2010  Belledonne Communications SARL 
Author: Simon Morlat <simon.morlat@linphone.org>

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*/

#include "mediastreamer2/msfilter.h"
#include <speex/speex_echo.h>
#include <speex/speex_preprocess.h>

#ifdef HAVE_CONFIG_H
#include "mediastreamer-config.h"
#endif

#ifdef WIN32
#include <malloc.h> /* for alloca */
#endif

static const int framesize=128;
static const int ref_max_delay=70;

#if 0
typedef struct _BufferSizeEstimator{
        float mean;
        float jitter;
}BufferSizeEstimator;

void buffer_size_estimator_update(BufferSizeEstimator *bse, int size){
        static const float smooth=0.04;
}

#endif

typedef struct SpeexECState{
        SpeexEchoState *ecstate;
        SpeexPreprocessState *den;
        MSBufferizer ref;
        MSBufferizer delayed_ref;
        MSBufferizer echo;
        int ref_bytes_limit;
        int framesize;
        int filterlength;
        int samplerate;
        int delay_ms;
        int tail_length_ms;
        bool_t using_silence;
        bool_t echostarted;
}SpeexECState;

static void speex_ec_init(MSFilter *f){
        SpeexECState *s=(SpeexECState *)ms_new(SpeexECState,1);

        s->samplerate=8000;
        ms_bufferizer_init(&s->ref);
        ms_bufferizer_init(&s->delayed_ref);
        ms_bufferizer_init(&s->echo);
        s->delay_ms=0;
        s->tail_length_ms=250;
        s->ecstate=NULL;
        s->framesize=framesize;
        s->den = NULL;
        s->using_silence=FALSE;
        s->echostarted=FALSE;

        f->data=s;
}

static void speex_ec_uninit(MSFilter *f){
        SpeexECState *s=(SpeexECState*)f->data;
        ms_bufferizer_uninit(&s->ref);
        ms_bufferizer_uninit(&s->delayed_ref);
        ms_free(s);
}


static void speex_ec_preprocess(MSFilter *f){
        SpeexECState *s=(SpeexECState*)f->data;
        int delay_samples=0;
        mblk_t *m;

        s->echostarted=FALSE;
        s->filterlength=(s->tail_length_ms*s->samplerate)/1000;
        delay_samples=s->delay_ms*s->samplerate/1000;
        ms_message("Initializing speex echo canceler with framesize=%i, filterlength=%i, delay_samples=%i",
                s->framesize,s->filterlength,delay_samples);
        s->ref_bytes_limit=(2*ref_max_delay*s->samplerate)/1000;
        s->ecstate=speex_echo_state_init(s->framesize,s->filterlength);
        s->den = speex_preprocess_state_init(s->framesize, s->samplerate);
        speex_echo_ctl(s->ecstate, SPEEX_ECHO_SET_SAMPLING_RATE, &s->samplerate);
        speex_preprocess_ctl(s->den, SPEEX_PREPROCESS_SET_ECHO_STATE, s->ecstate);
        /* fill with zeroes for the time of the delay*/
        m=allocb(delay_samples*2,0);
        ms_bufferizer_put (&s->delayed_ref,m);
}

/*      inputs[0]= reference signal (sent to soundcard)
 *      inputs[1]= near speech & echo signal    (read from soundcard)
 *      outputs[1]=  near end speech, echo removed - towards far end
*/
static void speex_ec_process(MSFilter *f){
        SpeexECState *s=(SpeexECState*)f->data;
        int nbytes=s->framesize*2;
        mblk_t *refm;
        uint8_t *ref,*echo;
        int size;
        
        if (f->inputs[1]!=NULL){
                int maxsize;
                ms_bufferizer_put_from_queue (&s->echo,f->inputs[1]);
                maxsize=ms_bufferizer_get_avail(&s->echo);
                if (s->echostarted==FALSE && maxsize>0){
                        ms_message("speex_ec: starting receiving echo signal");
                        s->echostarted=TRUE;
                }
                if (maxsize>=s->ref_bytes_limit){
                        ms_message("ref_bytes_limit adjusted from %i to %i",s->ref_bytes_limit,maxsize);
                        s->ref_bytes_limit=maxsize;
                }
        }
        
        if (f->inputs[0]!=NULL){
                while((refm=ms_queue_get(f->inputs[0]))!=NULL){
                        mblk_t *cp=dupmsg(refm);
                        ms_bufferizer_put(&s->ref,refm);
                        ms_bufferizer_put(&s->delayed_ref,cp);
                }
        }
        
/*
        ms_message("echo bytes=%i, ref bytes=%i",ms_bufferizer_get_avail(&s->echo),
                   ms_bufferizer_get_avail(&s->ref));
*/
        ref=(uint8_t*)alloca(nbytes);
        echo=(uint8_t*)alloca(nbytes);
        while (ms_bufferizer_read(&s->echo,echo,nbytes)>=nbytes){
                mblk_t *oref=allocb(nbytes,0);
                mblk_t *oecho=allocb(nbytes,0);
                if (ms_bufferizer_read(&s->ref,oref->b_wptr,nbytes)==0){
                        memset(ref,0,nbytes);
                        memset(oref->b_wptr,0,nbytes);
                        /*missing data, use silence instead*/
                        if (!s->using_silence){
                                ms_warning("No ref samples, using silence instead");
                                s->using_silence=TRUE;
                        }
                }else{
                        ms_bufferizer_read(&s->delayed_ref,ref,nbytes);
                        if (s->using_silence){
                                ms_warning("Reference stream is back.");
                                s->using_silence=FALSE;
                        }
                }
                oref->b_wptr+=nbytes;
                ms_queue_put(f->outputs[0],oref);
                speex_echo_cancellation(s->ecstate,(short*)echo,(short*)ref,(short*)oecho->b_wptr);
                speex_preprocess_run(s->den, (short*)oecho->b_wptr);
                oecho->b_wptr+=nbytes;
                ms_queue_put(f->outputs[1],oecho);
        }
        if (!s->echostarted){
                /*if we have not yet receive anything from the soundcard, bypass the reference signal*/
                while (ms_bufferizer_get_avail(&s->ref)>=nbytes){
                        mblk_t *oref=allocb(nbytes,0);
                        ms_bufferizer_read(&s->ref,oref->b_wptr,nbytes);
                        oref->b_wptr+=nbytes;
                        ms_bufferizer_skip_bytes(&s->delayed_ref,nbytes);
                        ms_queue_put(f->outputs[0],oref);
                }
        }

        /* do not accumulate too much reference signal */
        if ((size=ms_bufferizer_get_avail(&s->ref))> (s->ref_bytes_limit+nbytes)) {
                /* remove nbytes bytes */
                ms_warning("purging %i bytes from ref signal, size=%i, limit=%i",nbytes,size,s->ref_bytes_limit);
                ms_bufferizer_skip_bytes(&s->ref,nbytes);
                ms_bufferizer_skip_bytes(&s->delayed_ref,nbytes);
        }
}

static void speex_ec_postprocess(MSFilter *f){
        SpeexECState *s=(SpeexECState*)f->data;
        ms_bufferizer_flush (&s->ref);
        ms_bufferizer_flush (&s->delayed_ref);
        ms_bufferizer_flush (&s->echo);
        if (s->ecstate!=NULL){
                speex_echo_state_destroy(s->ecstate);
                s->ecstate=NULL;
        }
        if (s->den!=NULL){
                speex_preprocess_state_destroy(s->den);
                s->den=NULL;
        }
}

static int speex_ec_set_sr(MSFilter *f, void *arg){
        SpeexECState *s=(SpeexECState*)f->data;
        s->samplerate = *(int*)arg;
        return 0;
}

static int speex_ec_set_framesize(MSFilter *f, void *arg){
        SpeexECState *s=(SpeexECState*)f->data;
        s->framesize = *(int*)arg;
        return 0;
}

static int speex_ec_set_delay(MSFilter *f, void *arg){
        SpeexECState *s=(SpeexECState*)f->data;
        s->delay_ms = *(int*)arg;
        return 0;
}

static int speex_ec_set_tail_length(MSFilter *f, void *arg){
        SpeexECState *s=(SpeexECState*)f->data;
        s->tail_length_ms=*(int*)arg;
        return 0;
}


static MSFilterMethod speex_ec_methods[]={
        {       MS_FILTER_SET_SAMPLE_RATE, speex_ec_set_sr },
        {       MS_ECHO_CANCELLER_SET_TAIL_LENGTH       ,       speex_ec_set_tail_length        },
        {       MS_ECHO_CANCELLER_SET_DELAY             ,       speex_ec_set_delay              },
        {       MS_ECHO_CANCELLER_SET_FRAMESIZE ,       speex_ec_set_framesize          },
};

#ifdef _MSC_VER

MSFilterDesc ms_speex_ec_desc={
        MS_SPEEX_EC_ID,
        "MSSpeexEC",
        N_("Echo canceller using speex library"),
        MS_FILTER_OTHER,
        NULL,
        2,
        2,
        speex_ec_init,
        speex_ec_preprocess,
        speex_ec_process,
        speex_ec_postprocess,
        speex_ec_uninit,
        speex_ec_methods
};

#else

MSFilterDesc ms_speex_ec_desc={
        .id=MS_SPEEX_EC_ID,
        .name="MSSpeexEC",
        .text=N_("Echo canceller using speex library"),
        .category=MS_FILTER_OTHER,
        .ninputs=2,
        .noutputs=2,
        .init=speex_ec_init,
        .preprocess=speex_ec_preprocess,
        .process=speex_ec_process,
        .postprocess=speex_ec_postprocess,
        .uninit=speex_ec_uninit,
        .methods=speex_ec_methods
};

#endif

MS_FILTER_DESC_EXPORT(ms_speex_ec_desc)