84    SpeexDecorrState *st = speex_alloc(sizeof(SpeexDecorrState));  in speex_decorrelate_new()  local
85    st->rate = rate;  in speex_decorrelate_new()
86    st->channels = channels;  in speex_decorrelate_new()
87    st->frame_size = frame_size;  in speex_decorrelate_new()
89    st->psy = vorbis_psy_init(rate, 2*frame_size);  in speex_decorrelate_new()
90    spx_drft_init(&st->lookup, 2*frame_size);  in speex_decorrelate_new()
91    st->wola_mem = speex_alloc(frame_size*sizeof(float));  in speex_decorrelate_new()
92    st->curve = speex_alloc(frame_size*sizeof(float));  in speex_decorrelate_new()
94    st->y = speex_alloc(frame_size*sizeof(float));  in speex_decorrelate_new()
96    st->buff = speex_alloc(channels*2*frame_size*sizeof(float));  in speex_decorrelate_new()
97    st->ringID = speex_alloc(channels*sizeof(int));  in speex_decorrelate_new()
98    st->order = speex_alloc(channels*sizeof(int));  in speex_decorrelate_new()
99    st->alpha = speex_alloc(channels*sizeof(float));  in speex_decorrelate_new()
100    st->ring = speex_alloc(channels*ALLPASS_ORDER*sizeof(float));  in speex_decorrelate_new()
103    st->vorbis_win = speex_alloc((2*frame_size+20)*sizeof(float));  in speex_decorrelate_new()
105       st->vorbis_win[i] = sin(.5*M_PI* sin(M_PI*i/(2*frame_size))*sin(M_PI*i/(2*frame_size)) );  in speex_decorrelate_new()
106    st->seed = rand();  in speex_decorrelate_new()
111          st->ring[ch][i] = 0;  in speex_decorrelate_new()
112       st->ringID[ch] = 0;  in speex_decorrelate_new()
113       st->alpha[ch] = 0;  in speex_decorrelate_new()
114       st->order[ch] = 10;  in speex_decorrelate_new()
116    return st;  in speex_decorrelate_new()
137 EXPORT void speex_decorrelate(SpeexDecorrState *st, const spx_int16_t *in, spx_int16_t *out, int st…  in speex_decorrelate()  argument
148    for (ch=0;ch<st->channels;ch++)  in speex_decorrelate()
151       int N=2*st->frame_size;  in speex_decorrelate()
162       buff = st->buff+ch*2*st->frame_size;  in speex_decorrelate()
163       ring = st->ring[ch];  in speex_decorrelate()
164       ringID = st->ringID[ch];  in speex_decorrelate()
165       order = st->order[ch];  in speex_decorrelate()
166       alpha = st->alpha[ch];  in speex_decorrelate()
168       for (i=0;i<st->frame_size;i++)  in speex_decorrelate()
169          buff[i] = buff[i+st->frame_size];  in speex_decorrelate()
170       for (i=0;i<st->frame_size;i++)  in speex_decorrelate()
171          buff[i+st->frame_size] = in[i*st->channels+ch];  in speex_decorrelate()
173       x = buff+st->frame_size;  in speex_decorrelate()
183       for (i=0;i<st->frame_size;i++)  in speex_decorrelate()
185 …st->y[i] = alpha*(x[i-ALLPASS_ORDER+order]-beta*x[i-ALLPASS_ORDER+order-1])*st->vorbis_win[st->fra…  in speex_decorrelate()
186                + x[i-ALLPASS_ORDER]*st->vorbis_win[st->frame_size+i]   in speex_decorrelate()
189          ring[ringID++]=st->y[i];  in speex_decorrelate()
190          st->y[i] *= st->vorbis_win[st->frame_size+i];  in speex_decorrelate()
194       order = order+(irand(&st->seed)%3)-1;  in speex_decorrelate()
204       alpha = alpha + .4*uni_rand(&st->seed);  in speex_decorrelate()
212       for (i=0;i<st->frame_size;i++)  in speex_decorrelate()
214 …float tmp =  alpha*(x[i-ALLPASS_ORDER+order]-beta*x[i-ALLPASS_ORDER+order-1])*st->vorbis_win[i+ord…  in speex_decorrelate()
215                + x[i-ALLPASS_ORDER]*st->vorbis_win[i]   in speex_decorrelate()
219          tmp *= st->vorbis_win[i];  in speex_decorrelate()
222          st->y[i] += tmp;  in speex_decorrelate()
228       for (i=0;i<2*st->frame_size;i++)  in speex_decorrelate()
232       compute_curve(st->psy, buff, st->curve);  in speex_decorrelate()
233       for (i=1;i<st->frame_size;i++)  in speex_decorrelate()
238             x1 = uni_rand(&st->seed);  in speex_decorrelate()
239             x2 = uni_rand(&st->seed);  in speex_decorrelate()
241          gain = coef*sqrt(.1+st->curve[i]);  in speex_decorrelate()
245       frame[0] = coef*uni_rand(&st->seed)*sqrt(.1+st->curve[0]);  in speex_decorrelate()
246       frame[2*st->frame_size-1] = coef*uni_rand(&st->seed)*sqrt(.1+st->curve[st->frame_size-1]);  in speex_decorrelate()
247       spx_drft_backward(&st->lookup,frame);  in speex_decorrelate()
248       for (i=0;i<2*st->frame_size;i++)  in speex_decorrelate()
249          frame[i] *= st->vorbis_win[i];  in speex_decorrelate()
252       for (i=0;i<st->frame_size;i++)  in speex_decorrelate()
255          float tmp = st->y[i] + frame[i] + st->wola_mem[i];  in speex_decorrelate()
256          st->wola_mem[i] = frame[i+st->frame_size];  in speex_decorrelate()
258          float tmp = st->y[i];  in speex_decorrelate()
264          out[i*st->channels+ch] = tmp;  in speex_decorrelate()
267       st->ringID[ch] = ringID;  in speex_decorrelate()
268       st->order[ch] = order;  in speex_decorrelate()
269       st->alpha[ch] = alpha;  in speex_decorrelate()
274 EXPORT void speex_decorrelate_destroy(SpeexDecorrState *st)  in speex_decorrelate_destroy()  argument
277    vorbis_psy_destroy(st->psy);  in speex_decorrelate_destroy()
278    speex_free(st->wola_mem);  in speex_decorrelate_destroy()
279    speex_free(st->curve);  in speex_decorrelate_destroy()
281    speex_free(st->buff);  in speex_decorrelate_destroy()
282    speex_free(st->ring);  in speex_decorrelate_destroy()
283    speex_free(st->ringID);  in speex_decorrelate_destroy()
284    speex_free(st->alpha);  in speex_decorrelate_destroy()
285    speex_free(st->vorbis_win);  in speex_decorrelate_destroy()
286    speex_free(st->order);  in speex_decorrelate_destroy()
287    speex_free(st->y);  in speex_decorrelate_destroy()
288    speex_free(st);  in speex_decorrelate_destroy()