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-rw-r--r--mpeglib/lib/splay/mpegAudioHeader.cpp268
1 files changed, 268 insertions, 0 deletions
diff --git a/mpeglib/lib/splay/mpegAudioHeader.cpp b/mpeglib/lib/splay/mpegAudioHeader.cpp
new file mode 100644
index 00000000..7e34b212
--- /dev/null
+++ b/mpeglib/lib/splay/mpegAudioHeader.cpp
@@ -0,0 +1,268 @@
+/*
+ stores information after we found a header.
+ Copyright (C) 2000 Martin Vogt
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU Library General Public License as published by
+ the Free Software Foundation.
+
+ For more information look at the file COPYRIGHT in this package
+
+ */
+
+
+
+#include "mpegAudioHeader.h"
+
+#define DEBUG_HEADER(x)
+//#define DEBUG_HEADER(x) x
+
+
+#include <iostream>
+
+using namespace std;
+
+static const int frequencies[3][3]= {
+ {44100,48000,32000}, // MPEG 1
+ {22050,24000,16000}, // MPEG 2
+ {11025,12000,8000} // MPEG 2.5
+};
+
+static int translate[3][2][16] = { { { 2,0,0,2,2,2,3,3,3,3,3,3,3,3,3,2 } ,
+ { 2,0,0,0,0,0,0,2,2,2,3,3,3,3,3,2 } } ,
+ { { 2,0,0,2,2,2,2,2,2,2,2,2,2,2,2,2 } ,
+ { 2,0,0,0,0,0,0,2,2,2,2,2,2,2,2,2 } } ,
+ { { 2,1,1,2,2,2,3,3,3,3,3,3,3,3,3,2 } ,
+ { 2,1,1,1,1,1,1,2,2,2,3,3,3,3,3,2 } } };
+
+
+static int sblims[5] = { 8 , 12 , 27, 30 , 30 };
+
+
+static const int bitrate[2][3][15]= {
+ // MPEG 1
+ {{0,32,64,96,128,160,192,224,256,288,320,352,384,416,448},
+ {0,32,48,56,64,80,96,112,128,160,192,224,256,320,384},
+ {0,32,40,48,56,64,80,96,112,128,160,192,224,256,320}},
+
+ // MPEG 2
+ {{0,32,48,56,64,80,96,112,128,144,160,176,192,224,256},
+ {0,8,16,24,32,40,48,56,64,80,96,112,128,144,160},
+ {0,8,16,24,32,40,48,56,64,80,96,112,128,144,160}}
+};
+
+
+MpegAudioHeader::MpegAudioHeader() {
+
+}
+
+
+MpegAudioHeader::~MpegAudioHeader() {
+}
+
+
+int MpegAudioHeader::getChannelbitrate() {
+ cout << "getChannelbitrate not implemented"<<endl;
+ return 0;
+}
+
+int MpegAudioHeader::parseHeader(unsigned char* buf){
+
+ int c;
+ int mpeg25=false;
+
+
+ // Analyzing
+ header[0]=buf[0];
+ header[1]=buf[1];
+ header[2]=buf[2];
+ header[3]=buf[3];
+
+ c=buf[1];
+ lmpeg25=false;
+ if ( (c&0xf0) == 0xe0) {
+ lmpeg25=true;
+ }
+
+ c&=0xf;
+ protection=c&1;
+ layer=4-((c>>1)&3);
+ // we catch the layer==4 error later, for now go on with parsing
+ version=(int)(((c>>3)&1)^1);
+ if ((version==0) && lmpeg25) {
+ DEBUG_HEADER(cout << "wrong lsf/mpeg25 combination"<<endl;)
+ return false;
+ }
+ c=buf[2];
+
+ c=((c))>>1;
+ padding=(c&1);
+ c>>=1;
+ frequency=(int)(c&3);
+ c>>=2;
+ bitrateindex=(int)c;
+ if(bitrateindex>=15) {
+ DEBUG_HEADER(cout << "bitrateindex error"<<endl;)
+ return false;
+ }
+ c=buf[3];
+
+ c=((unsigned int)(c))>>4;
+ extendedmode=c&3;
+ mode=(int)(c>>2);
+
+
+ // Making information
+ inputstereo= (mode==_MODE_SINGLE)?0:1;
+
+ //
+ // frequency can be 0,1 or 2 but the mask above allows 3 as well
+ // check now.
+ if (frequency > 2) {
+ DEBUG_HEADER(cout << "frequency value out of range"<<endl;)
+ return false;
+ }
+
+ //
+ // does not belong here should be in the layer specific parts. [START]
+ //
+
+ switch(layer) {
+ case 3:
+ subbandnumber=0;
+ stereobound=0;
+ tableindex=0;
+ break;
+ case 2:
+ tableindex = translate[frequency][inputstereo][bitrateindex];
+ subbandnumber = sblims[tableindex];
+ stereobound = subbandnumber;
+ /*
+ Now merge the tableindex, for the bitalloclengthtable
+ */
+ tableindex=tableindex>>1;
+ if(mode==_MODE_SINGLE)stereobound=0;
+ if(mode==_MODE_JOINT)stereobound=(extendedmode+1)<<2;
+
+ break;
+ case 1:
+ subbandnumber=MAXSUBBAND;
+ stereobound=subbandnumber;
+ tableindex=0;
+ if(mode==_MODE_SINGLE)stereobound=0;
+ if(mode==_MODE_JOINT)stereobound=(extendedmode+1)<<2;
+ break;
+ default:
+ DEBUG_HEADER(cout <<"unknown layer"<<endl;)
+ return false;
+ }
+
+ //
+ // does not belong here should be in the layer specific parts. [END]
+ //
+ frequencyHz=frequencies[version+lmpeg25][frequency];
+ // framesize & slots
+ if(layer==1) {
+ if (frequencyHz <= 0) {
+ return false;
+ }
+ framesize=(12000*bitrate[version][0][bitrateindex])/frequencyHz;
+
+ if(frequency==_FREQUENCY_44100 && padding)framesize++;
+ framesize<<=2;
+ } else {
+ int freq=frequencyHz<<version;
+ if (freq <= 0) {
+ return false;
+ }
+ framesize=(144000*bitrate[version][layer-1][bitrateindex])/freq;
+
+ if(padding)framesize++;
+ if(layer==3) {
+ if(version)
+ layer3slots=framesize-((mode==_MODE_SINGLE)?9:17)
+ -(protection?0:2)
+ -4;
+ else
+ layer3slots=framesize-((mode==_MODE_SINGLE)?17:32)
+ -(protection?0:2)
+ -4;
+ }
+ }
+ if (framesize <= 0) {
+ DEBUG_HEADER(cout << "framesize negative"<<endl;)
+ return false;
+ }
+ return true;
+
+}
+
+
+int MpegAudioHeader::getpcmperframe() {
+ int s;
+
+ s=32;
+ if(layer==3) {
+ s*=18;
+ if(version==0)s*=2;
+ }
+ else {
+ s*=SCALEBLOCK;
+ if(layer==2)s*=3;
+ }
+
+ return s;
+}
+
+
+void MpegAudioHeader::copyTo(MpegAudioHeader* dest) {
+ dest->protection=protection;
+ dest->layer=layer;
+ dest->version=version;
+ dest->padding=padding;
+ dest->frequency=frequency;
+ dest->frequencyHz=frequencyHz;
+ dest->bitrateindex=bitrateindex;
+ dest->extendedmode=extendedmode;
+ dest->mode=mode;
+ dest->inputstereo=inputstereo;
+ dest->channelbitrate=channelbitrate;
+ dest->tableindex=tableindex;
+ dest->subbandnumber=subbandnumber;
+ dest->stereobound=stereobound;
+ dest->framesize=framesize;
+ dest->layer3slots=layer3slots;
+ dest->lmpeg25=lmpeg25;
+}
+
+
+void MpegAudioHeader::print(const char* name) {
+ cout << "MpegAudioHeader [START]:"<<name<<endl;
+ printf("header:%1x%1x%1x%1x\n",header[0],header[1],header[2],header[3]);
+ cout << "getProtection:"<<getProtection()<<endl;
+ cout << "getLayer:"<<getLayer()<<endl;
+ cout << "getVersion:"<<getVersion()<<endl;
+ cout << "getPadding:"<<getPadding()<<endl;
+ cout << "getFrequency:"<<getFrequency()<<endl;
+ cout << "getFrequencyHz:"<<getFrequencyHz()<<endl;
+ cout << "getBitrateindex:"<<getBitrateindex()<<endl;
+ cout << "getExtendedmode:"<<getExtendedmode()<<endl;
+ cout << "getMode():"<<getMode()<<endl;
+ cout << "getInputstereo:"<<getInputstereo()<<endl;
+ cout << "getChannelbitrate:"<<getChannelbitrate()<<endl;
+ cout << "getTableindex:"<<getTableindex()<<endl;
+ cout << "getSubbandnumber:"<<getSubbandnumber()<<endl;
+ cout << "getStereobound:"<<getStereobound()<<endl;
+ cout << "getFramesize:"<<getFramesize()<<endl;
+ cout << "getLayer3slots:"<<getLayer3slots()<<endl;
+ cout << "getpcmperframe:"<<getpcmperframe()<<endl;
+ cout << "MpegAudioHeader [END]:"<<name<<endl;
+
+}
+
+
+
+
+
+
+
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