C++调用libmp3lame实现压缩WAV为MP3【附VS2013项目】

The LAME Project LAME is a high quality MPEG Audio Layer III (MP3) encoder licensed under the LGPL. 

VS2013项目(libmp3lame, 可直接编译)下载链接：http://pan.baidu.com/s/1eQnqS9c 密码：5mg3

/********************************************************************
	Created:	2012/04/13  21:52
	Filename: 	RLib_Mp3.cpp
	Author:		rrrfff
	Url:	    http://blog.csdn.net/rrrfff
*********************************************************************/
#include "RLib_File.h"
#include "RLib_GlobalizeString.h"
#include "support/libmp3lame/lame.h"
#include <mmreg.h>
#include <stdio.h>

#ifdef _USE_MP3

//-------------------------------------------------------------------------

#pragma pack(1)
struct WAVFILE
{
	struct RIFF_HEADER
	{
		char  szRiffID[4];     // 'R','I','F','F'
		DWORD dwRiffSize;      // file_length - sizeof(szRiffID) - sizeof(dwRiffSize)
		char  szRiffFormat[4]; // 'W','A','V','E'
	};
	struct FMT_BLOCK
	{
		char         szFmtID[4];// 'f','m','t',' '
		DWORD        dwFmtSize;
		union WAV_FORMAT
		{
			WAVEFORMATEX  wavFormatEx; //determined by dwFmtSize
			PCMWAVEFORMAT wavPCMFormat;//dwFmtSize == 16
		};
		WAV_FORMAT format;
	};
	// 	struct FACT_BLOCK
	// 	{
	// 		char  szFactID[4]; // 'f','a','c','t'
	// 		DWORD  dwFactSize;
	// 	};
	struct DATA_BLOCK
	{
		char szDataID[4];  // 'd','a','t','a'
		DWORD dwDataSize;
	};
	RIFF_HEADER header;
	FMT_BLOCK   fmt;
	//	FACT_BLOCK  fact;
	DATA_BLOCK  data;
};
#pragma pack()

//-------------------------------------------------------------------------

void ConvertFromWAVFile(String wav_path, String mp3_path)
{
	auto pcm = IO::File::Open(wav_path);
	if (pcm == nullptr) return;

	//skip wav file headers
#ifdef _DEBUG
	WAVFILE wav;
	pcm->Read(&wav, sizeof(wav));
#else
	pcm->Position = sizeof(WAVFILE);
#endif // _DEBUG

	FILE *mp3;
	if (fopen_s(&mp3, GlobalizeString(IO::Path::GetDosPath(mp3_path)).toGBK(), "wb+") != 0)
	{
		delete pcm;
		return;
	}

	lame_t lame = lame_init();
	lame_set_in_samplerate(lame, 44100);
	lame_set_VBR(lame, vbr_default);
	//  lame_set_bWriteVbrTag(lame, 0);
	lame_init_params(lame);

	short int     pcm_buffer[RLIB_DEFAULT_BUFFER_SIZE * sizeof(short int)];
	unsigned char mp3_buffer[RLIB_DEFAULT_BUFFER_SIZE * sizeof(short int)];
	//make sure...

	intptr_t read, write;
	do
	{
		read = pcm->Read(pcm_buffer, sizeof(pcm_buffer));
		if (read == 0){
			write = lame_encode_flush(lame, mp3_buffer, sizeof(mp3_buffer));
		}
		else{
			write = lame_encode_buffer_interleaved(lame,
												   pcm_buffer, static_cast<int>(read / sizeof(short int)), //what should I do?
												   mp3_buffer, sizeof(mp3_buffer));
		}
		fwrite(mp3_buffer, write, 1, mp3);
	} while (read > 0);

	lame_mp3_tags_fid(lame, mp3);
	lame_close(lame);
	fclose(mp3);
	delete pcm;
}
#endif // _USE_MP3