2 * RealAudio 2.0 (28.8K)
3 * Copyright (c) 2003 the ffmpeg project
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
32 float st1a[111],st1b[37],st1[37];
33 float st2a[38],st2b[11],st2[11];
38 static int ra288_decode_init(AVCodecContext * avctx)
40 Real288_internal *glob=avctx->priv_data;
41 memset(glob,0,sizeof(Real288_internal));
45 static void prodsum(float *tgt, float *src, int len, int n);
46 static void co(int n, int i, int j, float *in, float *out, float *st1, float *st2, const float *table);
47 static int pred(float *in, float *tgt, int n);
48 static void colmult(float *tgt, float *m1, const float *m2, int n);
52 static void unpack(unsigned short *tgt, unsigned char *src, unsigned int len)
58 for (x=0;x<len;tgt[x++]=0)
61 for (x=y=z=0;x<len/*was 38*/;x++) {
64 if (n<8) temp&=255>>(8-n);
73 static void update(Real288_internal *glob)
76 float buffer1[40],temp1[37];
77 float buffer2[8],temp2[11];
79 for (x=0,y=glob->phasep+5;x<40;buffer1[x++]=glob->output[(y++)%40]);
80 co(36,40,35,buffer1,temp1,glob->st1a,glob->st1b,table1);
81 if (pred(temp1,glob->st1,36))
82 colmult(glob->pr1,glob->st1,table1a,36);
84 for (x=0,y=glob->phase+1;x<8;buffer2[x++]=glob->history[(y++)%8]);
85 co(10,8,20,buffer2,temp2,glob->st2a,glob->st2b,table2);
86 if (pred(temp2,glob->st2,10))
87 colmult(glob->pr2,glob->st2,table2a,10);
90 /* Decode and produce output */
91 static void decode(Real288_internal *glob, unsigned int input)
100 for (x=36;x--;glob->sb[x+5]=glob->sb[x]);
102 p1=glob->sb+x;p2=glob->pr1;
103 for (sum=0,y=36;y--;sum-=(*(++p1))*(*(p2++)));
108 table=codetable+(input>>3)*5;
110 /* convert log and do rms */
111 for (sum=32,x=10;x--;sum-=glob->pr2[x]*glob->lhist[x]);
112 if (sum<0) sum=0; else if (sum>60) sum=60;
114 sumsum=exp(sum*0.1151292546497)*f; /* pow(10.0,sum/20)*f */
115 for (sum=0,x=5;x--;) { buffer[x]=table[x]*sumsum; sum+=buffer[x]*buffer[x]; }
116 if ((sum/=5)<1) sum=1;
118 /* shift and store */
119 for (x=10;--x;glob->lhist[x]=glob->lhist[x-1]);
120 *glob->lhist=glob->history[glob->phase]=10*log10(sum)-32;
122 for (x=1;x<5;x++) for (y=x;y--;buffer[x]-=glob->pr1[x-y-1]*buffer[y]);
126 f=glob->sb[4-x]+buffer[x];
127 if (f>4095) f=4095; else if (f<-4095) f=-4095;
128 glob->output[glob->phasep+x]=glob->sb[4-x]=f;
132 /* column multiply */
133 static void colmult(float *tgt, float *m1, const float *m2, int n)
136 *(tgt++)=(*(m1++))*(*(m2++));
139 static int pred(float *in, float *tgt, int n)
146 if (in[n]==0) return 0;
147 if ((f0=*in)<=0) return 0;
155 for (y=x;--y;f1+=(*(p1--))*(*(p2++)));
165 if ((f0+=f1*f2)<0) return 0;
169 static void co(int n, int i, int j, float *in, float *out, float *st1, float *st2, const float *table)
178 /* rotate and multiply */
183 work[x]=*(table++)*(*(st1++)=*(fp++));
186 prodsum(buffer1,work+n,i,n);
187 prodsum(buffer2,work+a,j,n);
190 *st2=*st2*(0.5625)+buffer1[x];
191 out[x]=*(st2++)+buffer2[x];
193 *out*=1.00390625; /* to prevent clipping */
196 /* product sum (lsf) */
197 static void prodsum(float *tgt, float *src, int len, int n)
206 for (sum=0,x=len;x--;sum+=(*p1++)*(*p2++));
211 static void * decode_block(AVCodecContext * avctx, unsigned char *in, signed short int *out,unsigned len)
214 Real288_internal *glob=avctx->priv_data;
215 unsigned short int buffer[len];
217 unpack(buffer,in,len);
220 glob->phasep=(glob->phase=x&7)*5;
221 decode(glob,buffer[x]);
222 for (y=0;y<5;*(out++)=8*glob->output[glob->phasep+(y++)]);
223 if (glob->phase==3) update(glob);
228 /* Decode a block (celp) */
229 static int ra288_decode_frame(AVCodecContext * avctx,
230 void *data, int *data_size,
231 uint8_t * buf, int buf_size)
235 if (buf_size < avctx->block_align)
237 av_log(avctx, AV_LOG_ERROR, "ffra288: Error! Input buffer is too small [%d<%d]\n",buf_size,avctx->block_align);
242 data = decode_block(avctx, buf, (signed short *)data, avctx->block_align);
244 *data_size = (char *)data - (char *)datao;
245 return avctx->block_align;
248 AVCodec ra_288_decoder =
253 sizeof(Real288_internal),