mistserver/lib/adts.cpp
2021-10-19 22:29:40 +02:00

143 lines
4 KiB
C++

#include "adts.h"
#include <cstdlib>
#include <cstring>
#include <sstream>
#include "defines.h"
namespace aac{
adts::adts(){
data = NULL;
len = 0;
}
adts::adts(const char *_data, unsigned long _len){
len = _len;
data = (char *)malloc(len);
memcpy(data, _data, len);
}
bool adts::sameHeader(const adts &rhs) const{
if (!rhs || !*this){return false;}
return (getAACProfile() == rhs.getAACProfile() && getFrequencyIndex() == rhs.getFrequencyIndex() &&
getChannelConfig() == rhs.getChannelConfig());
}
adts::adts(const adts &rhs){
data = NULL;
len = 0;
*this = rhs;
}
adts &adts::operator=(const adts &rhs){
if (data){free(data);}
len = rhs.len;
data = (char *)malloc(len);
memcpy(data, rhs.data, len);
return *this;
}
adts::~adts(){
if (data){free(data);}
}
unsigned long adts::getAACProfile() const{
if (!data || !len){return 0;}
return ((data[2] >> 6) & 0x03) + 1;
}
unsigned long adts::getFrequencyIndex() const{
if (!data || !len){return 0;}
return ((data[2] >> 2) & 0x0F);
}
unsigned long adts::getFrequency() const{
if (!data || len < 3){return 0;}
switch (getFrequencyIndex()){
case 0: return 96000; break;
case 1: return 88200; break;
case 2: return 64000; break;
case 3: return 48000; break;
case 4: return 44100; break;
case 5: return 32000; break;
case 6: return 24000; break;
case 7: return 22050; break;
case 8: return 16000; break;
case 9: return 12000; break;
case 10: return 11025; break;
case 11: return 8000; break;
case 12: return 7350; break;
default: return 0; break;
}
}
unsigned long adts::getChannelConfig() const{
if (!data || !len){return 0;}
return ((data[2] & 0x01) << 2) | ((data[3] >> 6) & 0x03);
}
unsigned long adts::getChannelCount() const{
if (!data || !len){return 0;}
return (getChannelConfig() == 7 ? 8 : getChannelConfig());
}
unsigned long adts::getHeaderSize() const{
if (!data || !len){return 0;}
return (data[1] & 0x01 ? 7 : 9);
}
unsigned long adts::getCompleteSize() const{
if (!data || len < 6){return 0;}
return (((data[3] & 0x03) << 11) | (data[4] << 3) | ((data[5] >> 5) & 0x07));
}
unsigned long adts::getPayloadSize() const{
unsigned long ret = getCompleteSize();
if (!ret){return ret;}// catch zero length
if (ret >= getHeaderSize()){
ret -= getHeaderSize();
}else{
return 0; // catch size less than header size (corrupt data)
}
return ret;
}
unsigned long adts::getSampleCount() const{
if (!data || len < 7){return 0;}
return ((data[6] & 0x03) + 1) * 1024; // Number of samples in this frame * 1024
}
char *adts::getPayload(){
if (!data || !len){return 0;}
return data + getHeaderSize();
}
std::string adts::toPrettyString() const{
std::stringstream res;
res << "ADTS packet (payload size: " << getPayloadSize() << ")" << std::endl;
int syncWord = (((int)data[0] << 4) | ((data[1] >> 4) & 0x0F));
if (syncWord != 0xfff){
res << " Sync word " << std::hex << syncWord << " != fff!" << std::endl;
}
if ((data[1] & 0x8) == 0x8){
res << " MPEG-2" << std::endl;
}else{
res << " MPEG-4" << std::endl;
}
if ((data[1] & 0x6) != 0){res << " Non-zero layer!" << std::endl;}
if ((data[1] & 0x1) == 0x0){res << " CRC present" << std::endl;}
res << " MPEG-4 audio object type: " << getAACProfile() << std::endl;
res << " Frequency: " << getFrequency() << "Hz" << std::endl;
res << " Channels: " << getChannelCount() << std::endl;
res << " Samples: " << getSampleCount() << std::endl;
return res.str();
}
adts::operator bool() const{
return hasSync() && len && len >= getHeaderSize() && getFrequency() && getChannelCount() &&
getSampleCount();
}
bool adts::hasSync() const{
return len && (((int)data[0] << 4) | ((data[1] >> 4) & 0x0F)) == 0xfff;
}
}// namespace aac