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-rw-r--r--mpeglib/lib/splay/mpeglayer2.cpp449
1 files changed, 449 insertions, 0 deletions
diff --git a/mpeglib/lib/splay/mpeglayer2.cpp b/mpeglib/lib/splay/mpeglayer2.cpp
new file mode 100644
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--- /dev/null
+++ b/mpeglib/lib/splay/mpeglayer2.cpp
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+/* MPEG/WAVE Sound library
+
+ (C) 1997 by Jung woo-jae */
+
+// Mpeglayer2.cc
+// It's for MPEG Layer 2
+
+
+#include "mpegsound.h"
+#include "synthesis.h"
+
+#include <iostream>
+
+using namespace std;
+
+#define BUGFIX
+#include "mpeg2tables.h"
+
+
+// workaround for buggy mpeg2 streams.
+// tested with 12 monkey cdi, worgked fine.
+// problem was: the stream produced ints
+// with access out of the tables
+// if we have such an access we set it to a zero entry
+#ifdef BUGFIX
+static int checkCodeRange(int code,const REAL* group) {
+ int back=0;
+ if (group == NULL) {
+ cout << "group null"<<endl;
+ return 0;
+ }
+ back=code;
+
+ if (group == group5bits) {
+ if (back > 27*3) {
+ // redirect to zero value
+ back=3;
+ }
+ return back;
+ }
+ if (group == group7bits) {
+ if (back > 125*3) {
+ back=6;
+ }
+ return back;
+ }
+ if (group == group10bits) {
+ if (back > 729*3) {
+ back=12;
+ }
+ return back;
+ }
+ DEBUG_LAYER(cout << "unknown group found!"<<endl;)
+ return -1;
+}
+
+
+#endif
+
+
+
+
+
+
+
+
+// Mpeg layer 2
+void Mpegtoraw::extractlayer2(void) {
+ int inputstereo=mpegAudioHeader->getInputstereo();
+ int tableindex=mpegAudioHeader->getTableindex();
+ int subbandnumber=mpegAudioHeader->getSubbandnumber();
+ int stereobound=mpegAudioHeader->getStereobound();
+
+ REAL fraction[MAXCHANNEL][3][MAXSUBBAND];
+ unsigned int bitalloc[MAXCHANNEL][MAXSUBBAND],
+ scaleselector[MAXCHANNEL][MAXSUBBAND];
+ REAL scalefactor[2][3][MAXSUBBAND];
+
+ const REAL *group[MAXCHANNEL][MAXSUBBAND];
+ unsigned int codelength[MAXCHANNEL][MAXSUBBAND];
+ REAL factor[MAXCHANNEL][MAXSUBBAND];
+ REAL c[MAXCHANNEL][MAXSUBBAND],d[MAXCHANNEL][MAXSUBBAND];
+
+ int s=stereobound,n=subbandnumber;
+
+
+ // Bitalloc
+ {
+ register int i;
+ register const int *t=bitalloclengthtable[tableindex];
+ for(i=0;i<s;i++,t++)
+ {
+ bitalloc[LS][i]=getbits(*t);
+ bitalloc[RS][i]=getbits(*t);
+ }
+ for(;i<n;i++,t++) {
+ bitalloc[LS][i]=bitalloc[RS][i]=getbits(*t);
+ }
+ }
+
+
+
+ // Scale selector
+ if(inputstereo)
+ for(register int i=0;i<n;i++)
+ {
+ if(bitalloc[LS][i])scaleselector[LS][i]=getbits(2);
+ if(bitalloc[RS][i])scaleselector[RS][i]=getbits(2);
+ }
+ else
+ for(register int i=0;i<n;i++)
+ if(bitalloc[LS][i])scaleselector[LS][i]=getbits(2);
+
+ // Scale index
+ {
+ register int i,j;
+
+
+ for(i=0;i<n;i++)
+ {
+ if((j=bitalloc[LS][i]))
+ {
+ if(!tableindex)
+ {
+ group[LS][i]=grouptableA[j];
+ codelength[LS][i]=codelengthtableA[j];
+ factor[LS][i]=factortableA[j];
+ c[LS][i]=ctableA[j];
+ d[LS][i]=dtableA[j];
+ }
+ else
+ {
+ if(i<=2)
+ {
+ group[LS][i]=grouptableB1[j];
+ codelength[LS][i]=codelengthtableB1[j];
+ factor[LS][i]=factortableB1[j];
+ c[LS][i]=ctableB1[j];
+ d[LS][i]=dtableB1[j];
+ }
+ else
+ {
+ group[LS][i]=grouptableB234[j];
+ if(i<=10)
+ {
+ codelength[LS][i]=codelengthtableB2[j];
+ factor[LS][i]=factortableB2[j];
+ c[LS][i]=ctableB2[j];
+ d[LS][i]=dtableB2[j];
+ }
+ else if(i<=22)
+ {
+ codelength[LS][i]=codelengthtableB3[j];
+ factor[LS][i]=factortableB3[j];
+ c[LS][i]=ctableB3[j];
+ d[LS][i]=dtableB3[j];
+ }
+ else
+ {
+ codelength[LS][i]=codelengthtableB4[j];
+ factor[LS][i]=factortableB4[j];
+ c[LS][i]=ctableB4[j];
+ d[LS][i]=dtableB4[j];
+ }
+ }
+ }
+
+
+ switch(scaleselector[LS][i])
+ {
+ case 0:scalefactor[LS][0][i]=scalefactorstable[getbits(6)];
+ scalefactor[LS][1][i]=scalefactorstable[getbits(6)];
+ scalefactor[LS][2][i]=scalefactorstable[getbits(6)];
+ break;
+ case 1:scalefactor[LS][0][i]=
+ scalefactor[LS][1][i]=scalefactorstable[getbits(6)];
+ scalefactor[LS][2][i]=scalefactorstable[getbits(6)];
+ break;
+ case 2:scalefactor[LS][0][i]=
+ scalefactor[LS][1][i]=
+ scalefactor[LS][2][i]=scalefactorstable[getbits(6)];
+ break;
+ case 3:scalefactor[LS][0][i]=scalefactorstable[getbits(6)];
+ scalefactor[LS][1][i]=
+ scalefactor[LS][2][i]=scalefactorstable[getbits(6)];
+ break;
+ default:
+ cout << "scaleselector left default never happens"<<endl;
+ break;
+ }
+ }
+
+
+ if(inputstereo && (j=bitalloc[RS][i]))
+ {
+ if(!tableindex)
+ {
+ group[RS][i]=grouptableA[j];
+ codelength[RS][i]=codelengthtableA[j];
+ factor[RS][i]=factortableA[j];
+ c[RS][i]=ctableA[j];
+ d[RS][i]=dtableA[j];
+ }
+ else
+ {
+ if(i<=2)
+ {
+ group[RS][i]=grouptableB1[j];
+ codelength[RS][i]=codelengthtableB1[j];
+ factor[RS][i]=factortableB1[j];
+ c[RS][i]=ctableB1[j];
+ d[RS][i]=dtableB1[j];
+ }
+ else
+ {
+ group[RS][i]=grouptableB234[j];
+ if(i<=10)
+ {
+ codelength[RS][i]=codelengthtableB2[j];
+ factor[RS][i]=factortableB2[j];
+ c[RS][i]=ctableB2[j];
+ d[RS][i]=dtableB2[j];
+ }
+ else if(i<=22)
+ {
+ codelength[RS][i]=codelengthtableB3[j];
+ factor[RS][i]=factortableB3[j];
+ c[RS][i]=ctableB3[j];
+ d[RS][i]=dtableB3[j];
+ }
+ else
+ {
+ codelength[RS][i]=codelengthtableB4[j];
+ factor[RS][i]=factortableB4[j];
+ c[RS][i]=ctableB4[j];
+ d[RS][i]=dtableB4[j];
+ }
+ }
+ }
+
+
+ switch(scaleselector[RS][i])
+ {
+ case 0 : scalefactor[RS][0][i]=scalefactorstable[getbits(6)];
+ scalefactor[RS][1][i]=scalefactorstable[getbits(6)];
+ scalefactor[RS][2][i]=scalefactorstable[getbits(6)];
+ break;
+ case 1 : scalefactor[RS][0][i]=
+ scalefactor[RS][1][i]=scalefactorstable[getbits(6)];
+ scalefactor[RS][2][i]=scalefactorstable[getbits(6)];
+ break;
+ case 2 : scalefactor[RS][0][i]=
+ scalefactor[RS][1][i]=
+ scalefactor[RS][2][i]=scalefactorstable[getbits(6)];
+ break;
+ case 3 : scalefactor[RS][0][i]=scalefactorstable[getbits(6)];
+ scalefactor[RS][1][i]=
+ scalefactor[RS][2][i]=scalefactorstable[getbits(6)];
+ break;
+ default:
+ cout << "scaleselector right default never happens"<<endl;
+ break;
+ }
+
+
+ }
+ }
+ }
+
+
+
+// Read Sample
+ {
+ register int i;
+
+ for(int l=0;l<SCALEBLOCK;l++)
+ {
+ // Read Sample
+ for(i=0;i<s;i++)
+ {
+ if(bitalloc[LS][i])
+ {
+ if(group[LS][i])
+ {
+ register const REAL *s;
+ int code=getbits(codelength[LS][i]);
+
+
+
+ code+=code<<1;
+#ifdef BUGFIX
+ // bugfix for bad streams
+ code=checkCodeRange(code,group[LS][i]);
+ if (code == -1) return;
+#endif
+ s=group[LS][i]+code;
+
+ fraction[LS][0][i]=s[0];
+ fraction[LS][1][i]=s[1];
+ fraction[LS][2][i]=s[2];
+ }
+ else
+ {
+ fraction[LS][0][i]=
+ REAL(getbits(codelength[LS][i]))*factor[LS][i]-1.0;
+ fraction[LS][1][i]=
+ REAL(getbits(codelength[LS][i]))*factor[LS][i]-1.0;
+ fraction[LS][2][i]=
+ REAL(getbits(codelength[LS][i]))*factor[LS][i]-1.0;
+ }
+ }
+ else fraction[LS][0][i]=fraction[LS][1][i]=fraction[LS][2][i]=0.0;
+
+
+ if(inputstereo && bitalloc[RS][i])
+ {
+ if(group[RS][i])
+ {
+ const REAL *s;
+ int code=getbits(codelength[RS][i]);
+
+ code+=code<<1;
+#ifdef BUGFIX
+ // bugfix for bad streams
+ code=checkCodeRange(code,group[RS][i]);
+ if (code == -1) return;
+#endif
+ s=group[RS][i]+code;
+
+ fraction[RS][0][i]=s[0];
+ fraction[RS][1][i]=s[1];
+ fraction[RS][2][i]=s[2];
+ }
+ else
+ {
+ fraction[RS][0][i]=
+ REAL(getbits(codelength[RS][i]))*factor[RS][i]-1.0;
+ fraction[RS][1][i]=
+ REAL(getbits(codelength[RS][i]))*factor[RS][i]-1.0;
+ fraction[RS][2][i]=
+ REAL(getbits(codelength[RS][i]))*factor[RS][i]-1.0;
+ }
+ }
+ else fraction[RS][0][i]=fraction[RS][1][i]=fraction[RS][2][i]=0.0;
+ }
+
+
+ for(;i<n;i++)
+ {
+ if(bitalloc[LS][i])
+ {
+ if(group[LS][i])
+ {
+ register const REAL *s;
+ int code=getbits(codelength[LS][i]);
+
+ code+=code<<1;
+#ifdef BUGFIX
+ // bugfix for bad streams
+ code=checkCodeRange(code,group[LS][i]);
+ if (code == -1) return;
+#endif
+ s=group[LS][i]+code;
+
+ fraction[LS][0][i]=fraction[RS][0][i]=s[0];
+ fraction[LS][1][i]=fraction[RS][1][i]=s[1];
+ fraction[LS][2][i]=fraction[RS][2][i]=s[2];
+ }
+ else
+ {
+ fraction[LS][0][i]=fraction[RS][0][i]=
+ REAL(getbits(codelength[LS][i]))*factor[LS][i]-1.0;
+ fraction[LS][1][i]=fraction[RS][1][i]=
+ REAL(getbits(codelength[LS][i]))*factor[LS][i]-1.0;
+ fraction[LS][2][i]=fraction[RS][2][i]=
+ REAL(getbits(codelength[LS][i]))*factor[LS][i]-1.0;
+ }
+ }
+ else fraction[LS][0][i]=fraction[LS][1][i]=fraction[LS][2][i]=
+ fraction[RS][0][i]=fraction[RS][1][i]=fraction[RS][2][i]=0.0;
+ }
+
+
+
+
+ //Fraction
+ if(lOutputStereo)
+ for(i=0;i<n;i++)
+ {
+ if(bitalloc[LS][i])
+ {
+ if(!group[LS][i])
+ {
+ fraction[LS][0][i]=(fraction[LS][0][i]+d[LS][i])*c[LS][i];
+ fraction[LS][1][i]=(fraction[LS][1][i]+d[LS][i])*c[LS][i];
+ fraction[LS][2][i]=(fraction[LS][2][i]+d[LS][i])*c[LS][i];
+ }
+
+ register REAL t=scalefactor[LS][l>>2][i];
+ fraction[LS][0][i]*=t;
+ fraction[LS][1][i]*=t;
+ fraction[LS][2][i]*=t;
+ }
+
+ if(bitalloc[RS][i])
+ {
+ if(!group[RS][i])
+ {
+ fraction[RS][0][i]=(fraction[RS][0][i]+d[RS][i])*c[LS][i];
+ fraction[RS][1][i]=(fraction[RS][1][i]+d[RS][i])*c[LS][i];
+ fraction[RS][2][i]=(fraction[RS][2][i]+d[RS][i])*c[LS][i];
+ }
+
+ register REAL t=scalefactor[RS][l>>2][i];
+ fraction[RS][0][i]*=t;
+ fraction[RS][1][i]*=t;
+ fraction[RS][2][i]*=t;
+ }
+ }
+ else
+ for(i=0;i<n;i++)
+ if(bitalloc[LS][i])
+ {
+ if(!group[LS][i])
+ {
+ fraction[LS][0][i]=(fraction[LS][0][i]+d[LS][i])*c[LS][i];
+ fraction[LS][1][i]=(fraction[LS][1][i]+d[LS][i])*c[LS][i];
+ fraction[LS][2][i]=(fraction[LS][2][i]+d[LS][i])*c[LS][i];
+ }
+
+ register REAL t=scalefactor[LS][l>>2][i];
+ fraction[LS][0][i]*=t;
+ fraction[LS][1][i]*=t;
+ fraction[LS][2][i]*=t;
+ }
+
+
+ for(;i<MAXSUBBAND;i++)
+ fraction[LS][0][i]=fraction[LS][1][i]=fraction[LS][2][i]=
+ fraction[RS][0][i]=fraction[RS][1][i]=fraction[RS][2][i]=0.0;
+
+ for(i=0;i<3;i++) {
+ synthesis->doSynth(lDownSample,lOutputStereo,
+ fraction[LS][i],fraction[RS][i]);
+ }
+
+ }
+ }
+}
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