ffmpeg 에서 aac adts 형식의 파일 을 분석 합 니 다.
4588 단어 파일 분석
코드 는 다음 과 같 습 니 다:
#include "stdafx.h"
#include
#ifdef _WIN32
//Windows
extern "C"
{
#include "libavcodec/avcodec.h"
#include "libavformat/avformat.h"
#include "libavutil/opt.h"
#include "libavutil/parseutils.h"
#include "libavutil/avutil.h"
};
#else
//Linux...
#ifdef __cplusplus
extern "C"
{
#endif
#include
#include
#include
#include
#include
#ifdef __cplusplus
};
#endif
#endif
typedef struct _adts_header
{
unsigned int syncword:12;// 0xfff, ADTS
unsigned char ID:1;//ID , ”MPEG identifier, set to ‘1’. See ISO/IEC 11172-3″, 0 ,
unsigned char layer:2;// 0
unsigned char protection_absent:1;//
unsigned char profile:2;// AAC, 01 Low Complexity(LC)--- AACLC
unsigned char sampling_frequency_index:4;// 0x3 48k ,0x4 44.1k, 0x5 32k
unsigned char private_bit:1;// 0
unsigned char channel_configuration:3;//
unsigned char original_copy:1;// 0
unsigned char home:1;// 0
unsigned char copyright_identification_bit:1;// 0
unsigned char copyright_identification_start:1;// 0
unsigned int frame_length:13;// ADTS ADTS raw data block
unsigned int adts_buffer_fullness:11;// 0x7FF
unsigned char number_of_raw_data_blocks_in_frame:2;// ADTS number_of_raw_data_blocks_in_frame + 1 AAC .
};
void Process()
{
BYTE *btData = NULL;
DWORD dwRead = 0;
HANDLE hFile = CreateFile(L"E:\\video\\test.aac", GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
if (hFile != INVALID_HANDLE_VALUE){
DWORD dwFilesize = GetFileSize(hFile, NULL);
btData = new BYTE[dwFilesize];
ReadFile(hFile, btData, dwFilesize, &dwRead, NULL);
CloseHandle(hFile);
}
if (dwRead < 9){
if (btData){
delete[] btData;
btData = NULL;
}
return;
}
int j = 0;
int i = 0;
int nAdtsHeader_Size = 9;// AAC adts , 9
while(i < dwRead - nAdtsHeader_Size){
if(btData[i] == 0xff && (btData[i + 1]>>4) == 0xf){// aac adts
DWORD dwErr = 0;
printf("%d %d %02x %x %x %x", j, i,
(btData[i]<<4) | (btData[i + 1]>>4),
(btData[i + 1]>>3) & 0x1,
(btData[i + 1]>>1) & 0x3,
btData[i + 1] & 0x1);
switch((btData[i + 2]>>6) & 0x3){
case 0:
printf(" Main");
break;
case 1:
printf(" LC");
break;
case 2:
printf(" SSR");
break;
default:
printf(" unknown");
break;
}
switch((btData[i + 2]>>2) & 0xF){
case 0:
printf(" 96000Hz");
break;
case 1:
printf(" 88200Hz");
break;
case 2:
printf(" 64000Hz");
break;
case 3:
printf(" 48000Hz");
break;
case 4:
printf(" 44100Hz");
break;
case 5:
printf(" 32000Hz");
break;
case 6:
printf(" 24000Hz");
break;
case 7:
printf(" 22050Hz");
break;
case 8:
printf(" 16000Hz");
break;
case 9:
printf(" 12000Hz");
break;
case 10:
printf(" 11025Hz");
break;
case 11:
printf(" 8000Hz");
break;
default:
printf(" unknown");
break;
}
printf("%x %x %x %x %x %x %d %02x %x
",
(btData[i + 2]>>1) & 0x1,
((btData[i + 2] & 0x1)<<2) | ((btData[i + 3]>>6) & 0x3),
(btData[i + 3]>>5) & 0x1,
(btData[i + 3]>>4) & 0x1,
(btData[i + 3]>>3) & 0x1,
(btData[i + 3]>>2) & 0x1,
(((btData[i + 3]) & 0x3)<<11) | (btData[i + 4])<<3 | ((btData[i + 5]>>5) & 0x7),
((btData[i + 5] & 0x1F)<<6)|((btData[i + 6]>>2) & 0x3F),
btData[i + 6] & 0x3);
j++;
i += (((btData[i + 3]) & 0x3)<<11) | (btData[i + 4])<<3 | ((btData[i + 5]>>5) & 0x7);//
}
else{
i++;
}
}
if (btData){
delete[] btData;
btData = NULL;
}
return;
}
int _tmain(int argc, _TCHAR* argv[])
{
Process();
return 0;
}
http://download.csdn.net/detail/sz76211822/9713309