用faad解碼AAC(ADTS封裝)

一個小程式，使用faad解碼AAC音頻，只能解碼ADTS封裝的幀。編譯好的程式可以從這裡下載：http://download.csdn.net/detail/gavinr/3782154

/** * faaddec.c * use faad library to decode AAC, only can decode frame with ADTS head  */#include <stdio.h>#include <memory.h>#include "faad.h"#define FRAME_MAX_LEN 1024*5 #define BUFFER_MAX_LEN 1024*1024void show_usage(){    printf("usage\nfaaddec src_file dst_file");}/** * fetch one ADTS frame */int get_one_ADTS_frame(unsigned char* buffer, size_t buf_size, unsigned char* data ,size_t* data_size){    size_t size = 0;    if(!buffer || !data || !data_size )    {        return -1;    }    while(1)    {        if(buf_size  < 7 )        {            return -1;        }        if((buffer[0] == 0xff) && ((buffer[1] & 0xf0) == 0xf0) )        {            size |= ((buffer[3] & 0x03) <<11);     //high 2 bit            size |= buffer[4]<<3;                //middle 8 bit            size |= ((buffer[5] & 0xe0)>>5);        //low 3bit            break;        }        --buf_size;        ++buffer;    }    if(buf_size < size)    {        return -1;    }    memcpy(data, buffer, size);    *data_size = size;        return 0;}int main(int argc, char* argv[]){    static unsigned char frame[FRAME_MAX_LEN];    static unsigned char buffer[BUFFER_MAX_LEN] = {0};    char src_file[128] = {0};    char dst_file[128] = {0};    FILE* ifile = NULL;    FILE* ofile = NULL;    unsigned long samplerate;    unsigned char channels;    NeAACDecHandle decoder = 0;    size_t data_size = 0;    size_t size = 0;    NeAACDecFrameInfo frame_info;    unsigned char* input_data = buffer;    unsigned char* pcm_data = NULL;    //analyse parameter    if(argc < 3)    {        show_usage();        return -1;    }    sscanf(argv[1], "%s", src_file);    sscanf(argv[2], "%s", dst_file);    ifile = fopen(src_file, "rb");    ofile = fopen(dst_file, "wb");    if(!ifile || !ofile)    {        printf("source or destination file");        return -1;    }     data_size = fread(buffer, 1, BUFFER_MAX_LEN, ifile);     //open decoder    decoder = NeAACDecOpen();        if(get_one_ADTS_frame(buffer, data_size, frame, &size) < 0)    {        return -1;    }    //initialize decoder    NeAACDecInit(decoder, frame, size, &samplerate, &channels);    printf("samplerate %d, channels %d\n", samplerate, channels);        while(get_one_ADTS_frame(input_data, data_size, frame, &size) == 0)    {       // printf("frame size %d\n", size);        //decode ADTS frame        pcm_data = (unsigned char*)NeAACDecDecode(decoder, &frame_info, frame, size);                 if(frame_info.error > 0)        {            printf("%s\n",NeAACDecGetErrorMessage(frame_info.error));                    }        else if(pcm_data && frame_info.samples > 0)        {            printf("frame info: bytesconsumed %d, channels %d, header_type %d\                object_type %d, samples %d, samplerate %d\n",                 frame_info.bytesconsumed,                 frame_info.channels, frame_info.header_type,                 frame_info.object_type, frame_info.samples,                 frame_info.samplerate);            fwrite(pcm_data, 1, frame_info.samples * frame_info.channels, ofile);      //2個通道            fflush(ofile);        }                data_size -= size;        input_data += size;    }        NeAACDecClose(decoder);    fclose(ifile);    fclose(ofile);return 0;}