2 * RealAudio 2.0 (28.8K)
3 * Copyright (c) 2003 the ffmpeg project
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
30 float st1a[111],st1b[37],st1[37];
31 float st2a[38],st2b[11],st2[11];
36 static int ra288_decode_init(AVCodecContext * avctx)
38 Real288_internal *glob=avctx->priv_data;
39 memset(glob,0,sizeof(Real288_internal));
43 static void prodsum(float *tgt, float *src, int len, int n);
44 static void co(int n, int i, int j, float *in, float *out, float *st1, float *st2, const float *table);
45 static int pred(float *in, float *tgt, int n);
46 static void colmult(float *tgt, float *m1, const float *m2, int n);
50 static void unpack(unsigned short *tgt, unsigned char *src, unsigned int len)
56 for (x=0;x<len;tgt[x++]=0)
59 for (x=y=z=0;x<len/*was 38*/;x++) {
62 if (n<8) temp&=255>>(8-n);
71 static void update(Real288_internal *glob)
74 float buffer1[40],temp1[37];
75 float buffer2[8],temp2[11];
77 for (x=0,y=glob->phasep+5;x<40;buffer1[x++]=glob->output[(y++)%40]);
78 co(36,40,35,buffer1,temp1,glob->st1a,glob->st1b,table1);
79 if (pred(temp1,glob->st1,36))
80 colmult(glob->pr1,glob->st1,table1a,36);
82 for (x=0,y=glob->phase+1;x<8;buffer2[x++]=glob->history[(y++)%8]);
83 co(10,8,20,buffer2,temp2,glob->st2a,glob->st2b,table2);
84 if (pred(temp2,glob->st2,10))
85 colmult(glob->pr2,glob->st2,table2a,10);
88 /* Decode and produce output */
89 static void decode(Real288_internal *glob, unsigned int input)
98 for (x=36;x--;glob->sb[x+5]=glob->sb[x]);
100 p1=glob->sb+x;p2=glob->pr1;
101 for (sum=0,y=36;y--;sum-=(*(++p1))*(*(p2++)));
106 table=codetable+(input>>3)*5;
108 /* convert log and do rms */
109 for (sum=32,x=10;x--;sum-=glob->pr2[x]*glob->lhist[x]);
110 if (sum<0) sum=0; else if (sum>60) sum=60;
112 sumsum=exp(sum*0.1151292546497)*f; /* pow(10.0,sum/20)*f */
113 for (sum=0,x=5;x--;) { buffer[x]=table[x]*sumsum; sum+=buffer[x]*buffer[x]; }
114 if ((sum/=5)<1) sum=1;
116 /* shift and store */
117 for (x=10;--x;glob->lhist[x]=glob->lhist[x-1]);
118 *glob->lhist=glob->history[glob->phase]=10*log10(sum)-32;
120 for (x=1;x<5;x++) for (y=x;y--;buffer[x]-=glob->pr1[x-y-1]*buffer[y]);
124 f=glob->sb[4-x]+buffer[x];
125 if (f>4095) f=4095; else if (f<-4095) f=-4095;
126 glob->output[glob->phasep+x]=glob->sb[4-x]=f;
130 /* column multiply */
131 static void colmult(float *tgt, float *m1, const float *m2, int n)
134 *(tgt++)=(*(m1++))*(*(m2++));
137 static int pred(float *in, float *tgt, int n)
144 if (in[n]==0) return 0;
145 if ((f0=*in)<=0) return 0;
153 for (y=x;--y;f1+=(*(p1--))*(*(p2++)));
163 if ((f0+=f1*f2)<0) return 0;
167 static void co(int n, int i, int j, float *in, float *out, float *st1, float *st2, const float *table)
176 /* rotate and multiply */
181 work[x]=*(table++)*(*(st1++)=*(fp++));
184 prodsum(buffer1,work+n,i,n);
185 prodsum(buffer2,work+a,j,n);
188 *st2=*st2*(0.5625)+buffer1[x];
189 out[x]=*(st2++)+buffer2[x];
191 *out*=1.00390625; /* to prevent clipping */
194 /* product sum (lsf) */
195 static void prodsum(float *tgt, float *src, int len, int n)
204 for (sum=0,x=len;x--;sum+=(*p1++)*(*p2++));
209 static void * decode_block(AVCodecContext * avctx, unsigned char *in, signed short int *out,unsigned len)
212 Real288_internal *glob=avctx->priv_data;
213 unsigned short int buffer[len];
215 unpack(buffer,in,len);
218 glob->phasep=(glob->phase=x&7)*5;
219 decode(glob,buffer[x]);
220 for (y=0;y<5;*(out++)=8*glob->output[glob->phasep+(y++)]);
221 if (glob->phase==3) update(glob);
226 /* Decode a block (celp) */
227 static int ra288_decode_frame(AVCodecContext * avctx,
228 void *data, int *data_size,
229 uint8_t * buf, int buf_size)
233 if (buf_size < avctx->block_align)
235 av_log(avctx, AV_LOG_ERROR, "ffra288: Error! Input buffer is too small [%d<%d]\n",buf_size,avctx->block_align);
240 data = decode_block(avctx, buf, (signed short *)data, avctx->block_align);
242 *data_size = (char *)data - (char *)datao;
243 return avctx->block_align;
246 AVCodec ra_288_decoder =
251 sizeof(Real288_internal),