PCM文件转WAV文件
PCM文件转成WAV文件，只要加一个表头就够了。
这里假设采样率22050,采样精度16比特，双通道。Intel数端方式存放数据。
因为PCM源文件是四字节对齐，所以以四字节为单位Copy数据。
下面的源代码片段，示例库函数如何调用
FILE *fpS; FILE *fpD; fpS = fopen(ws2s(wsPCMFileName).c_str(),"rb"); fpD = fopen(ws2s(wsWAVEFileName).c_str(),"wb+"); if(fpS==NULL||fpD==NULL) { ::OutputDebugString(L"[CIrrReplay::createScene]PCM转WAVE失败！/n"); return; } fseek(fpS, 0, SEEK_END); long filelength = ftell(fpS); writeWaveHead(fpD); writeWaveBody(fpD,filelength); fseek(fpS,44,SEEK_SET); #define UNIT 4 char buf[UNIT]; while(UNIT==fread(buf,1,UNIT,fpS)) { fwrite(buf,1,UNIT,fpD); } fclose(fpS); fclose(fpD);
下面是待调用库的头文件
#pragma once #include <stdio.h> #include <Windows.h> #include <string> struct RIFF_HEADER { char szRiffID[4]; // 'R','I','F','F' DWORD dwRiffSize; char szRiffFormat[4]; // 'W','A','V','E' }; struct WAVE_FORMAT { WORD wFormatTag; WORD wChannels; DWORD dwSamplesPerSec; DWORD dwAvgBytesPerSec; WORD wBlockAlign; WORD wBitsPerSample; }; struct FMT_BLOCK { char szFmtID[4]; // 'f','m','t',' ' DWORD dwFmtSize; WAVE_FORMAT wavFormat; }; struct DATA_BLOCK { char szDataID[4]; // 'd','a','t','a' DWORD dwDataSize; }; union DWORD_CHAR { int nValue; char charBuf[4]; }; void writeWaveHead(FILE *fp); void writeWaveBody(FILE *fp,long filelength);
下面是待调用库的源文件
#include "PCM2WAVE.h" #include <memory.h> #include <string.h> /* Name: writeFile2Int Description: 在已知文件的指定位置，写一个整数 这里假设，int类型占四个字节 Parameter:sFN 文件名 nWhere 准备写的位置（以零开始计数） nValue 具体值。 Remark: 若文件长度小于nWhere，数据写到文件位置0开始的地方 TestEnv: VS2008+SP1 32位程序 */ bool writeFile2Int(FILE *fp,int nWhere,int nValue) { if(fp==NULL) { return false; } fseek(fp,nWhere,SEEK_SET); DWORD_CHAR dc; dc.nValue=nValue; fwrite(dc.charBuf,1,4,fp); return true; } void writeWaveHead(FILE *fp) { if (fp) { //写WAV文件头 RIFF_HEADER rh; memset(&rh,0,sizeof(rh)); strncpy(rh.szRiffFormat,"WAVE",4); strncpy(rh.szRiffID,"RIFF",4); //rh.dwRiffSize = dataSize + 4 + sizeof(FMT_BLOCK) + sizeof(rh) - 8;//文件大小减去8 fwrite(&rh,1,sizeof(rh),fp); FMT_BLOCK fb; strncpy(fb.szFmtID,"fmt ",4); fb.dwFmtSize = 16; fb.wavFormat.wFormatTag = 0x0001; fb.wavFormat.wChannels = 2; fb.wavFormat.wBitsPerSample = 16; fb.wavFormat.dwSamplesPerSec = 22050; fb.wavFormat.wBlockAlign = fb.wavFormat.wChannels*fb.wavFormat.wBitsPerSample/8; //4; fb.wavFormat.dwAvgBytesPerSec = fb.wavFormat.dwSamplesPerSec * fb.wavFormat.wBlockAlign; fwrite(&fb,1,sizeof(fb),fp); char buf[]={"data0000"}; fwrite(buf,1,sizeof(buf),fp); } } void writeWaveBody(FILE *fp,long filelength) { //更新WAV文件dwRiffSize字段中的值 int nWhere = 4; writeFile2Int(fp,nWhere, filelength - 8); //更新WAV文件DataChunk中Size字段的值 nWhere=sizeof(RIFF_HEADER)+sizeof(FMT_BLOCK)+4; writeFile2Int(fp,nWhere,filelength - (sizeof(RIFF_HEADER)+sizeof(FMT_BLOCK)+8) ); }