北京理工大学 20981 陈罡
xvid静态库用起来虽然速度很快，但是很不方便，有必要用c++把它好好封装一下，方便开发人员使用。下面的代码已经在p2p视频会议中采用，很好用，速度也很快。
xvid编码器头文件：
#ifndef _XVID_ENCODE_H
#define _XVID_ENCODE_H
#include
class CXvidEncHandler {
public:
virtual void PostEncHandler(unsigned char * xvid, int key, int xvid_len) = 0 ;
};
class CXvidEnc {
protected:
// original encode routine in xvid lib
int enc_core(unsigned char *image, unsigned char *bitstream, int *key);
public:
CXvidEnc() ;
~CXvidEnc() ;
bool Open();
bool Close();
static void XVID_GLOBAL_INIT();
void Encode(unsigned char * image);
void AttachCaller(int width, int height, CXvidEncHandler * enc_caller) ;
protected:
CXvidEncHandler* m_enc_caller ;
void * m_enc_handle;
unsigned char* m_bitstream;
bool m_closed;
int m_key ;
int m_width ;
int m_height ;
};
#endif
编码器源文件：
#include "StdAfx.h"
#include ".\xvidenc.h"
#include "xvid.h"
static const int motion_presets[] = {
/* quality 0 */
0,
/* quality 1 */
XVID_ME_ADVANCEDDIAMOND16,
/* quality 2 */
XVID_ME_ADVANCEDDIAMOND16 | XVID_ME_HALFPELREFINE16,
/* quality 3 */
XVID_ME_ADVANCEDDIAMOND16 | XVID_ME_HALFPELREFINE16 |
XVID_ME_ADVANCEDDIAMOND8 | XVID_ME_HALFPELREFINE8,
/* quality 4 */
XVID_ME_ADVANCEDDIAMOND16 | XVID_ME_HALFPELREFINE16 |
XVID_ME_ADVANCEDDIAMOND8 | XVID_ME_HALFPELREFINE8 |
XVID_ME_CHROMA_PVOP | XVID_ME_CHROMA_BVOP,
/* quality 5 */
XVID_ME_ADVANCEDDIAMOND16 | XVID_ME_HALFPELREFINE16 |
XVID_ME_ADVANCEDDIAMOND8 | XVID_ME_HALFPELREFINE8 |
XVID_ME_CHROMA_PVOP | XVID_ME_CHROMA_BVOP,
/* quality 6 */
XVID_ME_ADVANCEDDIAMOND16 | XVID_ME_HALFPELREFINE16 | XVID_ME_EXTSEARCH16 |
XVID_ME_ADVANCEDDIAMOND8 | XVID_ME_HALFPELREFINE8 | XVID_ME_EXTSEARCH8 |
XVID_ME_CHROMA_PVOP | XVID_ME_CHROMA_BVOP,
};
#define ME_ELEMENTS (sizeof(motion_presets)/sizeof(motion_presets[0]))
static const int vop_presets[] = {
/* quality 0 */
0,
/* quality 1 */
0,
/* quality 2 */
XVID_VOP_HALFPEL,
/* quality 3 */
XVID_VOP_HALFPEL | XVID_VOP_INTER4V,
/* quality 4 */
XVID_VOP_HALFPEL | XVID_VOP_INTER4V,
/* quality 5 */
XVID_VOP_HALFPEL | XVID_VOP_INTER4V |
XVID_VOP_TRELLISQUANT,
/* quality 6 */
XVID_VOP_HALFPEL | XVID_VOP_INTER4V |
XVID_VOP_TRELLISQUANT | XVID_VOP_HQACPRED,
};
#define VOP_ELEMENTS (sizeof(vop_presets)/sizeof(vop_presets[0]))
//////////////////////////////////////////////////////////////////////////
#define MAX_ZONES 64
/* Maximum number of frames to encode */
#define ABS_MAXFRAMENR 9999
static int ARG_STATS = 0;
static int ARG_DUMP = 0;
static int ARG_LUMIMASKING = 0;
static int ARG_BITRATE = 0;
static int ARG_SINGLE = 0;
static char *ARG_PASS1 = 0;
static char *ARG_PASS2 = 0;
static int ARG_QUALITY = ME_ELEMENTS - 1;
static float ARG_FRAMERATE = 25.00f;
static int ARG_MAXFRAMENR = ABS_MAXFRAMENR;
static int ARG_MAXKEYINTERVAL = 0;
static char *ARG_INPUTFILE = NULL;
static int ARG_INPUTTYPE = 0;
static int ARG_SAVEMPEGSTREAM = 0;
static int ARG_SAVEINDIVIDUAL = 0;
static char *ARG_OUTPUTFILE = NULL;
static int ARG_BQRATIO = 150;
static int ARG_BQOFFSET = 100;
static int ARG_MAXBFRAMES = 0;
static int ARG_PACKED = 0;
static int ARG_VOPDEBUG = 0;
static int ARG_GMC = 0;
static int ARG_INTERLACING = 0;
static int ARG_QPEL = 0;
static int ARG_CLOSED_GOP = 0;
#ifndef READ_PNM
#define IMAGE_SIZE(x,y) ((x)*(y)*3/2)
#else
#define IMAGE_SIZE(x,y) ((x)*(y)*3)
#endif
#define MAX(A,B) ( ((A)>(B)) ? (A) : (B) )
#define SMALL_EPS (1e-10)
#define SWAP(a) ( (((a)&0x000000ff)<<24) | (((a)&0x0000ff00)<<8) | (((a)&0x00ff0000)>>8) | (((a)&0xff000000)>>24) )
//////////////////////////////////////////////////////////////////////////
CXvidEnc::CXvidEnc()
{
m_closed = true ;
m_enc_caller = NULL ;
m_enc_handle = NULL ;
m_key = 0 ;
m_width = 0 ;
m_height = 0 ;
m_bitstream = NULL ;
}
CXvidEnc::~CXvidEnc() {
if(m_bitstream) free(m_bitstream) ;
m_bitstream = NULL ;
}
bool CXvidEnc::Close() {
int xerr = 0 ;
m_closed = true;
/* Destroy the encoder instance */
xerr = xvid_encore(m_enc_handle, XVID_ENC_DESTROY, NULL, NULL);
return (xerr) ? false : true ;
}
void CXvidEnc::AttachCaller(int width, int height, CXvidEncHandler * enc_caller)
{
m_width = width ;
m_height = height ;
m_enc_caller = enc_caller ;
if(m_width > 0 && m_height > 0) {
// max size
int max = (m_width > m_height) ? m_width : m_height ;
int xvid_len = (int)(max * max) ;
m_bitstream = (unsigned char *)malloc(xvid_len) ;
memset(m_bitstream, 0, xvid_len) ;
CXvidEnc::XVID_GLOBAL_INIT() ;
}
}
void CXvidEnc::XVID_GLOBAL_INIT(){
/*------------------------------------------------------------------------
* XviD core initialization
*----------------------------------------------------------------------*/
xvid_gbl_init_t xvid_gbl_init;
memset(&xvid_gbl_init, 0, sizeof(xvid_gbl_init));
xvid_gbl_init.version = XVID_VERSION;
xvid_gbl_init.cpu_flags = XVID_CPU_FORCE | XVID_CPU_ASM ; // here we use asm optimized code
/* Initialize XviD core -- Should be done once per __process__ */
xvid_global(NULL, XVID_GBL_INIT, &xvid_gbl_init, NULL);
}
bool CXvidEnc::Open() {
if(!m_enc_caller) return false ;
static xvid_enc_create_t xvid_enc_create;
int xerr = 0;
m_closed = false;
/*------------------------------------------------------------------------
* XviD encoder initialization
*----------------------------------------------------------------------*/
memset(&xvid_enc_create, 0, sizeof(xvid_enc_create));
xvid_enc_create.version = XVID_VERSION;
/* Width and Height of input frames */
xvid_enc_create.width = m_width ;
xvid_enc_create.height = m_height ;
xvid_enc_create.profile = XVID_PROFILE_AS_L4;
/* init plugins */
/*
xvid_enc_create.zones = ZONES;
xvid_enc_create.num_zones = NUM_ZONES;
xvid_enc_create.plugins = plugins;
xvid_enc_create.num_plugins = 0;
*/
/* No fancy thread tests */
xvid_enc_create.num_threads = 0;
/* Frame rate - Do some quick float fps = fincr/fbase hack */
xvid_enc_create.fincr = 1;
xvid_enc_create.fbase = (int)10;
/* Maximum key frame interval */
xvid_enc_create.max_key_interval = (int)-1; //--default 10s
/* Bframes settings */
xvid_enc_create.max_bframes = ARG_MAXBFRAMES;
xvid_enc_create.bquant_ratio = ARG_BQRATIO;
xvid_enc_create.bquant_offset = ARG_BQOFFSET;
/* Dropping ratio frame -- we don't need that */
xvid_enc_create.frame_drop_ratio = 0;
/* Global encoder options */
xvid_enc_create.global = 0;
if (ARG_PACKED)
xvid_enc_create.global |= XVID_GLOBAL_PACKED;
if (ARG_CLOSED_GOP)
xvid_enc_create.global |= XVID_GLOBAL_CLOSED_GOP;
if (ARG_STATS)
xvid_enc_create.global |= XVID_GLOBAL_EXTRASTATS_ENABLE;
/* I use a small value here, since will not encode whole movies, but short clips */
xerr = xvid_encore(NULL, XVID_ENC_CREATE, &xvid_enc_create, NULL);
m_enc_handle = xvid_enc_create.handle;
return true;
}
void CXvidEnc::Encode(unsigned char * image) {
int ret = 0 ;
if(m_closed) return;
ret = enc_core(image, m_bitstream, &m_key) ;
// really encode some images into xvid data
if (ret > 0)
m_enc_caller->PostEncHandler(m_bitstream, m_key, ret) ;
}
/*
raw CXvidEnc procedure
*/
int CXvidEnc::enc_core(unsigned char *image,unsigned char *bitstream, int * key)
{
int ret;
xvid_enc_frame_t xvid_enc_frame;
xvid_enc_stats_t xvid_enc_stats;
/* Version for the frame and the stats */
memset(&xvid_enc_frame, 0, sizeof(xvid_enc_frame));
xvid_enc_frame.version = XVID_VERSION;
memset(&xvid_enc_stats, 0, sizeof(xvid_enc_stats));
xvid_enc_stats.version = XVID_VERSION;
/* Bind output buffer */
xvid_enc_frame.bitstream = bitstream;
xvid_enc_frame.length = -1;
/* Initialize input image fields */
xvid_enc_frame.input.plane[0] = image;
xvid_enc_frame.input.csp = XVID_CSP_BGR; // suppose we get data from usb web cam
xvid_enc_frame.input.stride[0] = m_width*3;
/* Set up core's general features */
xvid_enc_frame.vol_flags = 0;
/* Set up core's general features */
xvid_enc_frame.vop_flags = vop_presets[ARG_QUALITY-2];
/* Frame type -- let core decide for us */
xvid_enc_frame.type = XVID_TYPE_AUTO;
/* Force the right quantizer -- It is internally managed by RC plugins */
xvid_enc_frame.quant = 0;
/* Set up motion estimation flags */
xvid_enc_frame.motion = motion_presets[ARG_QUALITY-2];
/* We don't use special matrices */
xvid_enc_frame.quant_intra_matrix = NULL;
xvid_enc_frame.quant_inter_matrix = NULL;
/* Encode the frame */
ret = xvid_encore(m_enc_handle, XVID_ENC_ENCODE, &xvid_enc_frame,NULL);
// &xvid_enc_stats);
//--判别是否是关键帧
*key = (xvid_enc_frame.out_flags & XVID_KEYFRAME);
//*stats_type = xvid_enc_stats.type;
//*stats_quant = xvid_enc_stats.quant;
//*stats_length = xvid_enc_stats.length;
//sse[0] = xvid_enc_stats.sse_y;
//sse[1] = xvid_enc_stats.sse_u;
//sse[2] = xvid_enc_stats.sse_v;
return (ret);
}
解码器头文件：
#ifndef _XVID_DECODE_H
#define _XVID_DECODE_H
#include
class CXvidDecHandler {
public:
virtual void PostDecHandler(unsigned char * image, int used_bytes) = 0 ;
};
class CXvidDec {
public:
CXvidDec() ;
~CXvidDec() ;
bool Open();
bool Close();
void Decode(unsigned char* xvid, int xvid_len);
static void XVID_GLOBAL_INIT();
void AttachCaller(int width, int height, CXvidDecHandler * dec_caller) ;
protected:
int dec_core(unsigned char *bitstream, unsigned char *image, int bs_size) ;
protected:
CXvidDecHandler* m_dec_caller ;
void* m_dec_handle ;
unsigned char * m_image ;
int m_width ;
int m_height ;
};
#endif
解码器源文件：
#include "StdAfx.h"
#include ".\xviddec.h"
#include "xvid.h"
CXvidDec::CXvidDec() {
m_width = 0 ;
m_height = 0 ;
m_image = NULL ;
m_dec_handle = NULL ;
m_dec_caller = NULL ;
}
CXvidDec::~CXvidDec()
{
if(m_image) free(m_image) ;
m_image = NULL ;
}
void CXvidDec::AttachCaller(int width, int height, CXvidDecHandler * dec_caller)
{
m_width = width ;
m_height = height ;
m_dec_caller = dec_caller ;
if((m_width > 0) && (m_height > 0)) {
int image_len = m_width * m_height * 3 ;
m_image = (unsigned char *)malloc(image_len) ;
memset(m_image, 0, image_len) ;
CXvidDec::XVID_GLOBAL_INIT() ;
}
}
bool CXvidDec::Close(){
int xerr = 0 ;
/* Destroy the encoder instance */
xerr = xvid_decore(m_dec_handle, XVID_ENC_DESTROY, NULL, NULL);
return (xerr) ? false : true ;
}
void CXvidDec::XVID_GLOBAL_INIT() {
/*------------------------------------------------------------------------
* XviD core initialization
*----------------------------------------------------------------------*/
xvid_gbl_init_t xvid_gbl_init;
memset(&xvid_gbl_init, 0, sizeof(xvid_gbl_init));
xvid_gbl_init.version = XVID_VERSION;
xvid_gbl_init.cpu_flags = XVID_CPU_FORCE | XVID_CPU_ASM ; // force to use asm optimized routine
/* Initialize XviD core -- Should be done once per __process__ */
xvid_global(NULL, XVID_GBL_INIT, &xvid_gbl_init, NULL);
}
bool CXvidDec::Open() {
if(!m_dec_caller) return false ;
static xvid_dec_create_t xvid_dec_create ;
int ret = 0;
/*------------------------------------------------------------------------
* XviD encoder initialization
*----------------------------------------------------------------------*/
memset(&xvid_dec_create, 0, sizeof(xvid_dec_create_t));
xvid_dec_create.version = XVID_VERSION;
/* Width and Height of input frames */
xvid_dec_create.width = m_width ;
xvid_dec_create.height = m_height ;
ret = xvid_decore(NULL, XVID_DEC_CREATE, &xvid_dec_create, NULL) ;
m_dec_handle = xvid_dec_create.handle;
return true;
}
void CXvidDec::Decode(unsigned char * xvid, int xvid_len) {
int ret = 0;
ret = dec_core(xvid, m_image, xvid_len);
if (ret > 0)
m_dec_caller->PostDecHandler(m_image, ret) ;
}
/* raw xvid_encode procedure */
int CXvidDec::dec_core(unsigned char *bitstream,unsigned char *image, int bs_size)
{
int ret;
xvid_dec_frame_t xvid_dec_frame;
/* Reset all structures */
memset(&xvid_dec_frame, 0, sizeof(xvid_dec_frame_t));
/* Set version */
xvid_dec_frame.version = XVID_VERSION;
//xvid_dec_stats->version = XVID_VERSION;
/* No general flags to set */
xvid_dec_frame.general = 0;
/* Input stream */
xvid_dec_frame.bitstream = bitstream;
xvid_dec_frame.length = bs_size;
/* Output frame structure */
xvid_dec_frame.output.plane[0] = image;
xvid_dec_frame.output.stride[0] = m_width*3;
xvid_dec_frame.output.csp = XVID_CSP_BGR;
ret = xvid_decore(m_dec_handle, XVID_DEC_DECODE, &xvid_dec_frame, NULL);
return(ret);
}
大家关注到这里编解码器有两个虚基类：CXvidDecHandler和CXvidEncHandler，使用的时候从这两个类派生，然后重载它即可。注意，这里是为了配合摄像头使用所以是直接对BGR24格式的数据进行编解码，如果对yuv420原始数据进行编解码，需要略微调整一下代码。
在这里我列一下使用流程：
（1）重载虚基类：
class CCapSvrDlg : public CDialog,
public CXvidEncHandler, // xvid encode handler
public CXvidDecHandler // xvid decode handler
{ ...
（2）重载纯虚函数：
public: // override the CXvidEncHandler
void PostEncHandler(unsigned char * xvid, int key, int xvid_len) ;
public:
void PostDecHandler(unsigned char * image, int used_bytes) ;
这里的PostEncHandler和PostDecHandler分别代表编码或者解码完毕后的数据处理。
比如：调用编码，xvid编码完毕后，会自动调用这里重载的PostEncHandler，这里的xvid就是编码后的视频数据，xvid_len就是视频数据的长度，这个key就是标明当前编码是否为关键帧。
解码也是一样，不在赘述。
（3）定义编解码器指针：
CXvidEnc * m_vdo_enc ;
CXvidDec * m_vdo_dec ;
（4）在OnInitDialog中初始化：
m_vdo_enc = new CXvidEnc() ;
m_vdo_enc->AttachCaller(320, 240, this) ;
m_vdo_enc->Open() ;
m_vdo_dec = new CXvidDec() ;
m_vdo_dec->AttachCaller(320, 240, this) ;
m_vdo_dec->Open() ;
（5）编解码操作：
编码：
m_vdo_enc->Encode(pBuffer) ; // 这里pBuffer是BGR24的320x240的数据
编码如果成功，就会自动调用PostEncHandler函数，就可以得到编码后的结果
解码：
m_vdo_dec->Decode(xvid, xvid_len) ; // 传入的存有xvid数据的buffer和长度
解码成功后，会自动调用PostDecHandler，注意对于流媒体数据而言，在这个函数中还有一个形参是标明本次解码用掉了多少个字节的xvid缓冲区的数据，便于下一帧解码的时候调整缓冲区指针
（6）OnDestroy函数中，关闭编解码器
m_vdo_enc->Close() ;
m_vdo_dec->Close() ;
delete m_vdo_dec ;
delete m_vdo_enc ;
这些就是全部的xvid静态库的c++封装了，是不是特简单？只要编译一下xvid-core1.1.2即可。
链接的时候，需要libxvidcore.lib。
注意，debug版的需要debug版的libxvidcore.lib，release版的需要release版的xvidcore库。
