H264视频编码成MP4文件_java h264转mp4

        最近需要将H264视频编码成MP4格式。研究了一下，一种方法是采用ffmpeg库，可以先将H264文件解码，再编码生成MP4文件，但这种方式效率较低，10M的视频可能需要几秒钟才能完成。另一种方式根据MP4文件协议直接将H264包封装成MP4格式，由于是直接基于MP4的封装，因而效率很高。H264可以很方便的封装成FLV文件，但MP4格式格式相对比较复杂，封装起来会比较麻烦。由于没时间研究MP4协议，在Google Code上找到一个开源的MP4编解码库Mp4v2（https://code.google.com/p/mp4v2/），通过Mp4v2可以很方便的将H264编码成MP4格式文件。为了方便使用，基于该库封装了一个MP4Encoder类，MP4Encoder封装的接口如下。目前仅支持将H264文件或数据帧编码成MP4文件。

class MP4Encoder
{
public:
	MP4Encoder(void);
	~MP4Encoder(void);
public:
	// open or creat a mp4 file.
	MP4FileHandle CreateMP4File(const char *fileName,int width,int height,int timeScale = 90000,int frameRate = 25);
	// wirte 264 metadata in mp4 file.
	bool Write264Metadata(MP4FileHandle hMp4File,LPMP4ENC_Metadata lpMetadata);
	// wirte 264 data, data can contain  multiple frame.
	int WriteH264Data(MP4FileHandle hMp4File,const unsigned char* pData,int size); 
    // close mp4 file.
	void CloseMP4File(MP4FileHandle hMp4File);
    // convert H264 file to mp4 file.
	// no need to call CreateMP4File and CloseMP4File,it will create/close mp4 file automaticly.
	bool WriteH264File(const char* pFile264,const char* pFileMp4);
	// Prase H264 metamata from H264 data frame
	static bool PraseMetadata(const unsigned char* pData,int size,MP4ENC_Metadata &metadata);
}; 

客户端调用示例代码：

#include <stdio.h>
#include "MP4Encoder\MP4Encoder.h"
 
int main(int argc, char** argv)
{
	MP4Encoder mp4Encoder;
	// convert H264 file to mp4 file
	mp4Encoder.WriteH264File("test.264","test.mp4");
}

MP4Encoder完整的代码如下：

/******************************************************************** 
filename:   MP4Encoder.h
created:    2013-04-16
author:     firehood 
purpose:    MP4编码器，基于开源库mp4v2实现（https://code.google.com/p/mp4v2/）。
*********************************************************************/
#pragma once
#include "mp4v2\mp4v2.h"
 
// NALU单元
typedef struct _MP4ENC_NaluUnit
{
	int type;
	int size;
	unsigned char *data;
}MP4ENC_NaluUnit;
 
typedef struct _MP4ENC_Metadata
{
	// video, must be h264 type
	unsigned int	nSpsLen;
	unsigned char	Sps[1024];
	unsigned int	nPpsLen;
	unsigned char	Pps[1024];
 
} MP4ENC_Metadata,*LPMP4ENC_Metadata;
 
class MP4Encoder
{
public:
	MP4Encoder(void);
	~MP4Encoder(void);
public:
	// open or creat a mp4 file.
	MP4FileHandle CreateMP4File(const char *fileName,int width,int height,int timeScale = 90000,int frameRate = 25);
	// wirte 264 metadata in mp4 file.
	bool Write264Metadata(MP4FileHandle hMp4File,LPMP4ENC_Metadata lpMetadata);
	// wirte 264 data, data can contain  multiple frame.
	int WriteH264Data(MP4FileHandle hMp4File,const unsigned char* pData,int size); 
    // close mp4 file.
	void CloseMP4File(MP4FileHandle hMp4File);
    // convert H264 file to mp4 file.
	// no need to call CreateMP4File and CloseMP4File,it will create/close mp4 file automaticly.
	bool WriteH264File(const char* pFile264,const char* pFileMp4);
	// Prase H264 metamata from H264 data frame
	static bool PraseMetadata(const unsigned char* pData,int size,MP4ENC_Metadata &metadata);
private:
	// read one nalu from H264 data buffer
	static int ReadOneNaluFromBuf(const unsigned char *buffer,unsigned int nBufferSize,unsigned int offSet,MP4ENC_NaluUnit &nalu);
private:
	int m_nWidth;
	int m_nHeight;
	int m_nFrameRate;
	int m_nTimeScale;
	MP4TrackId m_videoId;
}; 

MP4Encoder.cpp

/******************************************************************** 
filename:   MP4Encoder.cpp
created:    2013-04-16
author:     firehood 
purpose:    MP4编码器，基于开源库mp4v2实现（https://code.google.com/p/mp4v2/）。
*********************************************************************/
#include "MP4Encoder.h"
#include <string.h>
 
#define BUFFER_SIZE  (1024*1024)
 
MP4Encoder::MP4Encoder(void):
m_videoId(NULL),
m_nWidth(0),
m_nHeight(0),
m_nTimeScale(0),
m_nFrameRate(0)
{
}
 
MP4Encoder::~MP4Encoder(void)
{
}
 
MP4FileHandle MP4Encoder::CreateMP4File(const char *pFileName,int width,int height,int timeScale/* = 90000*/,int frameRate/* = 25*/)
{
	if(pFileName == NULL)
	{
		return false;
	}
	// create mp4 file
	MP4FileHandle hMp4file = MP4Create(pFileName);
	if (hMp4file == MP4_INVALID_FILE_HANDLE)
	{
		printf("ERROR:Open file fialed.\n");
		return false;
	}
	m_nWidth = width;
	m_nHeight = height;
	m_nTimeScale = 90000;
	m_nFrameRate = 25;
	MP4SetTimeScale(hMp4file, m_nTimeScale);
	return hMp4file;
}
 
bool MP4Encoder::Write264Metadata(MP4FileHandle hMp4File,LPMP4ENC_Metadata lpMetadata)
{
	m_videoId = MP4AddH264VideoTrack
		(hMp4File, 
		m_nTimeScale, 
		m_nTimeScale / m_nFrameRate, 
		m_nWidth, // width
		m_nHeight,// height
		lpMetadata->Sps[1], // sps[1] AVCProfileIndication
		lpMetadata->Sps[2], // sps[2] profile_compat
		lpMetadata->Sps[3], // sps[3] AVCLevelIndication
		3);           // 4 bytes length before each NAL unit
	if (m_videoId == MP4_INVALID_TRACK_ID)
	{
		printf("add video track failed.\n");
		return false;
	}
	MP4SetVideoProfileLevel(hMp4File, 0x01); //  Simple Profile @ Level 3
 
	// write sps
    MP4AddH264SequenceParameterSet(hMp4File,m_videoId,lpMetadata->Sps,lpMetadata->nSpsLen);
 
	// write pps
	MP4AddH264PictureParameterSet(hMp4File,m_videoId,lpMetadata->Pps,lpMetadata->nPpsLen);
 
	return true;
}
 
int MP4Encoder::WriteH264Data(MP4FileHandle hMp4File,const unsigned char* pData,int size)
{
	if(hMp4File == NULL)
	{
		return -1;
	}
	if(pData == NULL)
	{
		return -1;
	}
	MP4ENC_NaluUnit nalu;
	int pos = 0, len = 0;
	while (len = ReadOneNaluFromBuf(pData,size,pos,nalu))
	{
		if(nalu.type == 0x07) // sps
		{
			// 添加h264 track    
			m_videoId = MP4AddH264VideoTrack
				(hMp4File, 
				m_nTimeScale, 
				m_nTimeScale / m_nFrameRate, 
				m_nWidth,     // width
				m_nHeight,    // height
				nalu.data[1], // sps[1] AVCProfileIndication
				nalu.data[2], // sps[2] profile_compat
				nalu.data[3], // sps[3] AVCLevelIndication
				3);           // 4 bytes length before each NAL unit
			if (m_videoId == MP4_INVALID_TRACK_ID)
			{
				printf("add video track failed.\n");
				return 0;
			}
			MP4SetVideoProfileLevel(hMp4File, 1); //  Simple Profile @ Level 3
 
			MP4AddH264SequenceParameterSet(hMp4File,m_videoId,nalu.data,nalu.size);
		}
		else if(nalu.type == 0x08) // pps
		{
			MP4AddH264PictureParameterSet(hMp4File,m_videoId,nalu.data,nalu.size);
		}
		else
		{
			int datalen = nalu.size+4;
			unsigned char *data = new unsigned char[datalen];
			// MP4 Nalu前四个字节表示Nalu长度
			data[0] = nalu.size>>24;
			data[1] = nalu.size>>16;
			data[2] = nalu.size>>8;
			data[3] = nalu.size&0xff;
			memcpy(data+4,nalu.data,nalu.size);
			if(!MP4WriteSample(hMp4File, m_videoId, data, datalen,MP4_INVALID_DURATION, 0, 1))
			{
				return 0;
			}
			delete[] data;
		}
		
		pos += len;
	}
    return pos;
}
 
int MP4Encoder::ReadOneNaluFromBuf(const unsigned char *buffer,unsigned int nBufferSize,unsigned int offSet,MP4ENC_NaluUnit &nalu)
{
	int i = offSet;
	while(i<nBufferSize)
	{
		if(buffer[i++] == 0x00 &&
			buffer[i++] == 0x00 &&
			buffer[i++] == 0x00 &&
			buffer[i++] == 0x01
			)
		{
			int pos = i;
			while (pos<nBufferSize)
			{
				if(buffer[pos++] == 0x00 &&
					buffer[pos++] == 0x00 &&
					buffer[pos++] == 0x00 &&
					buffer[pos++] == 0x01
					)
				{
					break;
				}
			}
			if(pos == nBufferSize)
			{
				nalu.size = pos-i;	
			}
			else
			{
				nalu.size = (pos-4)-i;
			}
 
			nalu.type = buffer[i]&0x1f;
			nalu.data =(unsigned char*)&buffer[i];
			return (nalu.size+i-offSet);
		}
	}
	return 0;
}
 
void MP4Encoder::CloseMP4File(MP4FileHandle hMp4File)
{
	if(hMp4File)
	{
		MP4Close(hMp4File);
		hMp4File = NULL;
	}
}
 
bool MP4Encoder::WriteH264File(const char* pFile264,const char* pFileMp4)
{
    if(pFile264 == NULL || pFileMp4 == NULL)
	{
		return false;
	}
 
	MP4FileHandle hMp4File = CreateMP4File(pFileMp4,352,288);
 
    if(hMp4File == NULL)
	{
		printf("ERROR:Create file failed!");
		return false;
	}
 
	FILE *fp = fopen(pFile264, "rb");  
	if(!fp)  
	{  
		printf("ERROR:open file failed!");
		return false;
	}  
	fseek(fp, 0, SEEK_SET);
 
	unsigned char *buffer  = new unsigned char[BUFFER_SIZE];
	int pos = 0;
	while(1)
	{
		int readlen = fread(buffer+pos, sizeof(unsigned char), BUFFER_SIZE-pos, fp);
 
 
		if(readlen<=0)
		{
			break;
		}
 
		readlen += pos;
 
		int writelen = 0;
		for(int i = readlen-1; i>=0; i--)
		{
				if(buffer[i--] == 0x01 &&
					buffer[i--] == 0x00 &&
					buffer[i--] == 0x00 &&
					buffer[i--] == 0x00
					)
				{
					writelen = i+5;
					break;
				}
		}
		
		writelen = WriteH264Data(hMp4File,buffer,writelen);
		if(writelen<=0)
		{
			break;
		}
		memcpy(buffer,buffer+writelen,readlen-writelen+1);
		pos = readlen-writelen+1;
	}
	fclose(fp);
 
	delete[] buffer;
	CloseMP4File(hMp4File);
 
	return true;
}
 
bool MP4Encoder:: PraseMetadata(const unsigned char* pData,int size,MP4ENC_Metadata &metadata)
{
	if(pData == NULL || size<4)
	{
		return false;
	}
	MP4ENC_NaluUnit nalu;
	int pos = 0;
	bool bRet1 = false,bRet2 = false;
	while (int len = ReadOneNaluFromBuf(pData,size,pos,nalu))
	{
		if(nalu.type == 0x07)
		{
			memcpy(metadata.Sps,nalu.data,nalu.size);
			metadata.nSpsLen = nalu.size;
			bRet1 = true;
		}
		else if((nalu.type == 0x08))
		{
			memcpy(metadata.Pps,nalu.data,nalu.size);
			metadata.nPpsLen = nalu.size;
			bRet2 = true;
		}
		pos += len;
	}
	if(bRet1 && bRet2)
	{
		return true;
	}
	return false;
}