RealAudio 1.0 (14_4) and 2.0 (28_8) native decoders.

Author unknown, code from a public domain player for Amiga
at http://www.honeypot.net/audio


git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@10261 b3059339-0415-0410-9bf9-f77b7e298cf2

1 files changed, 217 insertions, 0 deletions

diff --git a/libmpcodecs/native/decode288.c b/libmpcodecs/native/decode288.c
new file mode 100644
index 0000000000..fb4f350ff6
--- /dev/null
+++ b/libmpcodecs/native/decode288.c
@@ -0,0 +1,217 @@
+#include "common1428.h"
+#include "decode288.h"
+#include "tables288.h"
+
+/* Initialize internal variable structure */
+Real_288 *init_288(void)
+{
+	Real_internal *glob;
+
+	if ((glob=malloc(sizeof(Real_internal))))
+	  memset(glob,0,sizeof(Real_internal));
+
+	return (Real_288 *)glob;
+}
+
+/* Free internal variable structure */
+void free_288(Real_288 *global)
+{
+	if (!global) return;
+	free(global);
+}
+
+/* Unlike the 14.4 format, 28.8 blocks are interleaved */
+/* to dilute the effects of transmission errors */
+void deinterleave(unsigned char *in, unsigned char *out, unsigned int size)
+{
+  unsigned int x=0,y=0,z=0;
+  if (size>=38) z=size-38;
+  else return;
+
+  while (x<=z)
+  {
+    memcpy(out+y,in+x,38);
+    x+=38;y+=456;
+    if (y>z) y-=z;
+  }
+}
+
+/* Decode a block (celp) */
+void decode_288(Real_288 *global, unsigned char *in, signed short int *out)
+{
+  int x,y;
+  unsigned short int buffer[32];
+  Real_internal *glob;
+
+  if (!global) return;
+  glob = (Real_internal *)global;
+
+  unpack(buffer,in,32);
+  for (x=0;x<32;x++)
+  {
+    glob->phasep=(glob->phase=x&7)*5;
+    decode(glob,buffer[x]);
+    for (y=0;y<5;*(out++)=8*glob->output[glob->phasep+(y++)]);
+    if (glob->phase==3) update(glob);
+  }
+}
+
+/* initial decode */
+static void unpack(unsigned short *tgt, unsigned char *src, int len)
+{
+  int x,y,z;
+  int n,temp;
+  int buffer[38];
+
+  for (x=0;x<len;tgt[x++]=0)
+    buffer[x]=9+(x&1);
+
+  for (x=y=z=0;x<38;x++) {
+    n=buffer[y]-z;
+    temp=src[x];
+    if (n<8) temp&=255>>(8-n);
+    tgt[y]+=temp<<z;
+    if (n<=8) {
+      tgt[++y]+=src[x]>>n;
+      z=8-n;
+    } else z+=8;
+  }
+}
+
+static void update(Real_internal *glob)
+{
+  int x,y;
+  float buffer1[40],temp1[37];
+  float buffer2[8],temp2[11];
+
+  for (x=0,y=glob->phasep+5;x<40;buffer1[x++]=glob->output[(y++)%40]);
+  co(36,40,35,buffer1,temp1,glob->st1a,glob->st1b,table1);
+  if (pred(temp1,glob->st1,36))
+    colmult(glob->pr1,glob->st1,table1a,36);
+
+  for (x=0,y=glob->phase+1;x<8;buffer2[x++]=glob->history[(y++)%8]);
+  co(10,8,20,buffer2,temp2,glob->st2a,glob->st2b,table2);
+  if (pred(temp2,glob->st2,10))
+    colmult(glob->pr2,glob->st2,table2a,10);
+}
+
+/* Decode and produce output */
+static void decode(Real_internal *glob, unsigned int input)
+{
+  unsigned int x,y;
+  float f;
+  double sum,sumsum;
+  float *p1,*p2;
+  float buffer[5];
+  const float *table;
+
+  for (x=36;x--;glob->sb[x+5]=glob->sb[x]);
+  for (x=5;x--;) {
+    p1=glob->sb+x;p2=glob->pr1;
+    for (sum=0,y=36;y--;sum-=(*(++p1))*(*(p2++)));
+    glob->sb[x]=sum;
+  }
+
+  f=amptable[input&7];
+  table=codetable+(input>>3)*5;
+
+  /* convert log and do rms */
+  for (sum=32,x=10;x--;sum-=glob->pr2[x]*glob->lhist[x]);
+  if (sum<0) sum=0; else if (sum>60) sum=60;
+
+  sumsum=exp(sum*0.1151292546497)*f;	/* pow(10.0,sum/20)*f */
+  for (sum=0,x=5;x--;) { buffer[x]=table[x]*sumsum; sum+=buffer[x]*buffer[x]; }
+  if ((sum/=5)<1) sum=1;
+
+  /* shift and store */
+  for (x=10;--x;glob->lhist[x]=glob->lhist[x-1]);
+  *glob->lhist=glob->history[glob->phase]=10*log10(sum)-32;
+
+  for (x=1;x<5;x++) for (y=x;y--;buffer[x]-=glob->pr1[x-y-1]*buffer[y]);
+
+  /* output */
+  for (x=0;x<5;x++) {
+    f=glob->sb[4-x]+buffer[x];
+    if (f>4095) f=4095; else if (f<-4095) f=-4095;
+    glob->output[glob->phasep+x]=glob->sb[4-x]=f;
+  }
+}
+
+/* column multiply */
+static void colmult(float *tgt, float *m1, const float *m2, int n)
+{
+  while (n--)
+    *(tgt++)=(*(m1++))*(*(m2++));
+}
+
+static int pred(float *in, float *tgt, int n)
+{
+  int x,y;
+  float *p1,*p2;
+  double f0,f1,f2;
+  float temp;
+
+  if (in[n]==0) return 0;
+  if ((f0=*in)<=0) return 0;
+
+  for (x=1;;x++) {
+    if (n<x) return 1;
+
+    p1=in+x;
+    p2=tgt;
+    f1=*(p1--);
+    for (y=x;--y;f1+=(*(p1--))*(*(p2++)));
+
+    p1=tgt+x-1;
+    p2=tgt;
+    *(p1--)=f2=-f1/f0;
+    for (y=x>>1;y--;) {
+      temp=*p2+*p1*f2;
+      *(p1--)+=*p2*f2;
+      *(p2++)=temp;
+    }
+    if ((f0+=f1*f2)<0) return 0;
+  }
+}
+
+static void co(int n, int i, int j, float *in, float *out, float *st1, float *st2, const float *table)
+{
+  int a,b,c;
+  unsigned int x;
+  float *fp,*fp2;
+  float buffer1[37];
+  float buffer2[37];
+  float work[111];
+
+  /* rotate and multiply */
+  c=(b=(a=n+i)+j)-i;
+  fp=st1+i;
+  for (x=0;x<b;x++) {
+    if (x==c) fp=in;
+    work[x]=*(table++)*(*(st1++)=*(fp++));
+  }
+  
+  prodsum(buffer1,work+n,i,n);
+  prodsum(buffer2,work+a,j,n);
+
+  for (x=0;x<=n;x++) {
+    *st2=*st2*(0.5625)+buffer1[x];
+    out[x]=*(st2++)+buffer2[x];
+  }
+  *out*=1.00390625; /* to prevent clipping */
+}
+
+/* product sum (lsf) */
+static void prodsum(float *tgt, float *src, int len, int n)
+{
+  unsigned int x;
+  float *p1,*p2;
+  double sum;
+
+  while (n>=0)
+  {
+    p1=(p2=src)-n;
+    for (sum=0,x=len;x--;sum+=(*p1++)*(*p2++));
+    tgt[n--]=sum;
+  }
+}