libfaac使用实例

本文对采集的未压缩声音装换为aac格式

对应录制篇：http://blog.163.com/zhujiatc@126/blog/static/183463820130208928612/

代码实例用到上文生成的文件

最后生成aac文件

#include <stdio.h>

#include <stdlib.h>

#include <windows.h>

#include <iostream.h>

#include <time.h>

#include "faac.h"

#pragma comment(lib, "libfaac.lib")

typedef unsigned long   ULONG;

typedef unsigned int    UINT;

typedef unsigned char   BYTE;

typedef char            _TCHAR;

int main(int argc, _TCHAR* argv[])

{

    ULONG nSampleRate = 44100;  // 采样率

    UINT nChannels = 2;         // 声道数

    UINT nBit = 16;             // 单样本位数

    ULONG nInputSamples = 0; //输入样本数

    ULONG nMaxOutputBytes = 0; //输出所需最大空间

ULONG nMaxInputBytes=0;     //输入最大字节

    int nRet;

    faacEncHandle hEncoder; //aac句柄

    faacEncConfigurationPtr pConfiguration;//aac设置指针 

    BYTE* pbPCMBuffer;

    BYTE* pbAACBuffer;

    FILE* fpIn; // PCM file for input

    FILE* fpOut; // AAC file for output

    fpIn = fopen("myvoice", "rb");

    fpOut = fopen("out.aac", "wb");

if (fpIn==NULL)

{

printf("can't find myvoice!\n");

return 0;

}

    // (1) Open FAAC engine

    hEncoder = faacEncOpen(nSampleRate, nChannels, &nInputSamples, &nMaxOutputBytes);//初始化aac句柄，同时获取最大输入样本，及编码所需最小字节

nMaxInputBytes=nInputSamples*nBit/8;//计算最大输入字节,跟据最大输入样本数

printf("nInputSamples:%d nMaxInputBytes:%d nMaxOutputBytes:%d\n", nInputSamples, nMaxInputBytes,nMaxOutputBytes);

    if(hEncoder == NULL)

    {

        printf("[ERROR] Failed to call faacEncOpen()\n");

        return -1;

    }

    pbPCMBuffer = new BYTE [nMaxInputBytes];

    pbAACBuffer = new BYTE [nMaxOutputBytes];

    // (2.1) Get current encoding configuration

    pConfiguration = faacEncGetCurrentConfiguration(hEncoder);//获取配置结构指针

    pConfiguration->inputFormat = FAAC_INPUT_16BIT;

pConfiguration->outputFormat=1;

pConfiguration->useTns=true;

pConfiguration->useLfe=false;

pConfiguration->aacObjectType=LOW;

pConfiguration->shortctl=SHORTCTL_NORMAL;

pConfiguration->quantqual=100;

pConfiguration->bandWidth=0;

pConfiguration->bitRate=0;

    // (2.2) Set encoding configuration

    nRet = faacEncSetConfiguration(hEncoder, pConfiguration);//设置配置，根据不同设置，耗时不一样

int temp1=clock();

    while(true)

    {

nRet=0;

        nRet = fread(pbPCMBuffer, 1, nMaxInputBytes, fpIn);

if(nRet < 1)

        {

            break;

        }

        // 计算实际输入样本数，

        nInputSamples = nRet/ (nBit / 8);

        // (3) Encode

        nRet = faacEncEncode(hEncoder, (int*) pbPCMBuffer, nInputSamples, pbAACBuffer, nMaxOutputBytes);

if (nRet<1)

{

continue;

}

        fwrite(pbAACBuffer, 1, nRet, fpOut);

    }  

while((nRet=faacEncEncode(hEncoder, NULL, 0, pbAACBuffer, nMaxOutputBytes))>0)

{

fwrite(pbAACBuffer, 1, nRet, fpOut);

}

printf("usetime:%d\n",clock()-temp1);

    // (4) Close FAAC engine 关闭acc句柄

    nRet = faacEncClose(hEncoder);

    delete[] pbPCMBuffer;

    delete[] pbAACBuffer;

    fclose(fpIn);

    fclose(fpOut);

    system("PAUSE");

    return 0;

}