VC捕捉摄像头图像入门源码要点

1、【转】vc捕捉摄像头图像入门源码vc捕捉摄像头图像入门源码(非常适合新手)(转)默认分类2009-11-02 17:46:56 阅读39评论0字号：大中 小此源码是我更改过的基于 vfw(video for windows)的源码，使用了定时器能 实时的显示图像，从网上可搜到原版源码，但是原版的功能是保存为一个文件， 且不能实时显示，此版本虽然能显示，但感觉反应速度不是很快，没有基于 directshow的程序更新速度快，不过在 wm_paint息处理里加while(1)capgrabframe(ghwndcap);刷新速度就快很多了，但是这样程序就进 入死循环不能再处理其他消息，至于怎样改进

2、，就靠读者你了。/源码的任何部分都可以在 msdn!查至ij,请参考 msdn#include <windows.h>#include <stdio.h>#include <vfw.h>#pragma comment(lib,"vfw32.lib")hwnd ghwndcap ; /f甫获窗的句柄capstatus gcapstatus ; / 捕获窗的状态capdrivercaps gcapdrivercaps ; 视频驱动的能力 char gachbuffer20;/char szcapturefile口 = "camcap

3、ture.avi"/ / statuscallbackproc: 册这个回调函数。/ hwnd:/ nid:/ lpstatustext:状态回调函数，使用capsetcallbackonstatus 宏来注捕获窗体句柄当前状态的状态码 当前状态的文本字符/lresult callback statuscallbackproc(hwnd hwnd,int nid,lpstr lpstatustext)if(!ghwndcap)return false;/获得捕获窗的状态capgetstatus(ghwndcap,&gcapstatus,sizeof(capstatus);/

4、更新捕获窗的大小 , 得到消息 wm_cap_get_statussetwindowpos(ghwndcap,null,0,0,gcapstatus.uiimagewidth,gcapstatus.uii mageheight,swp_nozorder|swp_nomove);if(nid=0)/ 清除旧的状态信息setwindowtext(ghwndcap,(lpstr)"hello");return (lresult)true;/ 显示状态 id 和状态文本wsprintf(gachbuffer,"status# %d: %s",nid,lpstat

5、ustext);setwindowtext(ghwndcap,(lpstr)gachbuffer);return (lresult)true;/ errorcallbackproc:错误回调函数, 过 capsetcallbackonerror 宏来 注册回调捕获窗口句柄错误代码关于错误的文本信息/ hwnd:/ nerrid: / lperrortext: /lresult callback errorcallbackproc(hwnd hwnd,int nerrid,lpstr lperrortext)if(!ghwndcap)return false;if(nerrid=0)return

6、 true;/ 清除旧的错误wsprintf(gachbuffer,"error# %d",nerrid);/ 显示错误标识和文本messagebox(hwnd, lperrortext, gachbuffer,mb_ok | mb_iconexclamation); return (lresult) true;/ framecallbackproc: 帧回调函数, 通过 capsetcallbackframe 宏来注册捕获窗体句柄指向一个包含帧信息的数据结构体回调函数/ hwnd:/ lpvhdr: / /lresult callback framecallbackpro

7、c(hwnd hwnd,lpvideohdr lpvhdr) file *fp;fp=fopen("caram.dat","w");if(!ghwndcap)return false;/ 假设 fp 为一打开的 .dat 文件指针fwrite(lpvhdr->lpdata,1,lpvhdr->dwbufferlength,fp); return (lresult)true;/ /timerproc 函数处理定时器，在这里抓取并显示图像/void callback timerproc(hwnd hwnd,/ handle to windowui

8、nt umsg,/ wm_timer messageuint_ptr idevent, / timer identifierdword dwtime/ current system time)capgrabframe(ghwndcap);/ 主回调函数/lresult callback windowproc(hwnd hwnd,/ handle to windowuint umsg,/ message identifierwparam wparam, / first message parameter lparam lparam / second message parameter )/ hd

9、c hdc;/ paintstruct ps;/ rect rect;switch(umsg)case wm_create:ghwndcap=capcreatecapturewindow(lpstr)"capture window",ws_child|ws_visible,0,0,320,240,(hwnd)hwnd,(int)0);capsetcallbackonerror(ghwndcap,(farproc)errorcallbackproc);capsetcallbackonstatus(ghwndcap,(farproc)statuscallbackproc); c

10、apsetcallbackonframe(ghwndcap,(farproc)framecallbackproc);capdriverconnect(ghwndcap,0); / 将捕获窗同驱动连接capdrivergetcaps(ghwndcap,&gcapdrivercaps,sizeof(capdrivercaps);/ 获得驱动的能力 , 相关的信息放在结构变量gcapdrivercaps 中cappreviewrate(ghwndcap, 66); /uses this macro to set the framedisplay rate for preview mode t

11、o 66 milliseconds per framecappreview(ghwndcap, true); /and then uses the cappreview macro to place the capture window in preview mode.if(gcapdrivercaps.fhasoverlay) / 检查驱动器是否有叠加能力capoverlay(ghwndcap,true); / 启动 overlay 模式if(gcapdrivercaps.fhasdlgvideosource)capdlgvideosource(ghwndcap);/video source

12、 对话框if(gcapdrivercaps.fhasdlgvideoformat)capdlgvideoformat(ghwndcap);/ video format 对话框if(gcapdrivercaps.fhasdlgvideodisplay)capdlgvideodisplay(ghwndcap); / video display 对话框/ capfilesetcapturefile( ghwndcap,szcapturefile); / 将要保存的文件名设为本源文件开头处的全局字符串常量/ capfilealloc(ghwndcap, (1024l * 1024l * 5); / 为

13、捕获文件分配存储空间capcapturesequence(ghwndcap); / 开始捕获视频序列/ capgrabframe(ghwndcap); / 捕获单帧图像settimer(hwnd,1,10,timerproc);break;case wm_paint:capgrabframe(ghwndcap);/* hdc=beginpaint(hwnd,&ps);getclientrect(hwnd,&rect);drawtext(hdc,text("hello,windowsxp!"),-1,&rect,dt_singleline|dt_cen

14、ter|dt_vcenter);endpaint(hwnd,&ps);*/break;case wm_close: if(idyes=messagebox(hwnd,"sure exit ?","camcapture",mb_yesno) destroywindow(hwnd); break;case wm_destroy:killtimer(hwnd,1);capsetcallbackonstatus(ghwndcap,null); capsetcallbackonerror(ghwndcap,null); capsetcallbackonfr

15、ame(ghwndcap,null); capcaptureabort(ghwndcap);/ 停止捕获 capdriverdisconnect(ghwndcap); / 将捕获窗同驱动断开 postquitmessage(0); break;default:return defwindowproc(hwnd,umsg,wparam,lparam); return 0;/ 主函数int winapi winmain(hinstance hinstance,/ handle to currentinstancehinstance hprevinstance, / handle to previo

16、us instancelpstr lpcmdline,/ command lineint ncmdshow/ show state) static tchar szappname=text("camcapture"); wndclass wndcls; hwnd hwnd; msg msg;wndcls.cbclsextra=0;wndcls.cbwndextra=0;wndcls.hbrbackground=(hbrush)getstockobject(black_brush); wndcls.hcursor=loadcursor(null,idc_cross); wnd

17、cls.hicon=loadicon(null,idi_question); wndcls.hinstance=hinstance;wndcls.lpfnwndproc=windowproc;wndcls.lpszclassname="camcapture"wndcls.lpszmenuname=null;wndcls.style=cs_hredraw | cs_vredraw;if(!registerclass(&wndcls)messagebox(null,text("this program requires windows nt!"),s

18、zappname,mb_iconerror);return 0;hwnd=createwindow("camcapture","camcapture",ws_overlappedwindow, cw_usedefault,cw_usedefault,320,240,null,null,hinstance,null);showwindow(hwnd,ncmdshow);updatewindow(hwnd);while(getmessage(&msg,null,0,0)translatemessage(&msg);dispatchmessag

19、e(&msg);return 0;摘要： 本文主要讲述用 directshow 进行视频捕捉 (捕捉静态图像) 的编程思路，并提供针对摄像头编程的一个视频捕捉类ccapturevideo 和一个示例。、户 、.前言directshow是微软公司提供的一套在 windows平台上进行流媒体处理的开发包，与 directx 开发包一起发布。 directshow 为多媒体流的捕捉和回放提供了强有力的支持。用 directshow 开发应用程序，我们可以很方便地从支持wdm驱动模型的采集卡上捕获数据，并且进行相应的后期处理乃至存储到文件中。directshow是基于com勺，为了编写 dir

20、ectshow应用程序，需要了解 com客户程序编写的基础知识。 directshow 提供了大量的接口，但在编程中发现还是不够方便， 如果能构建一个视频捕捉类把常用的一些动作封装起来， 那么就更方便了。编程思路为了更加容易建立视频捕捉应用程序， directshow 提供了一个叫做capturegraph builder 的对象， capture graph builder 提供 icapturegraphbuilder2 接口，该接口可以建立和控制 capture graph 。建立视频捕捉程序，必须首先获取并初始化 icapturegraphbuilder2 接口，然后选择一个适当的视频

21、捕捉设备。选择好设备后，为该设备创建capturefilter ，然后调用 addfilter 把 capture filter 添加到 filter graph 。如果仅仅希望用摄像头来进行实时监控的话，只需要在上面的基础上调用icapturegraphbuilder2:renderstream 就可以了：icapturegraphbuilder2 *pbuild; / capture graph builder/ 省略初始化部分代码ibasefilter *pcap; / video capture filter./ 省略初始化和添加到 filter graph 部分代码pbuild-&g

22、t;renderstream(&pin_category_preview, &mediatype_video, pcap, null, null);directshow 提供了一个捕捉静态图像的方法： 使用 samplegrabber filter 。依次按照以下三个步骤就可以了：第一步 , 定义一个类实现sample grabber 的回调接口 isamplegrabbercb ：class csamplegrabbercb : public isamplegrabbercb / 在后面提供的类中具体完成csamplegrabbercb mcb;第二步、调用 renderst

23、ream 依次把 still pin 、 sample grabber 和系统默 认 renderer filter 连接起来。第三步、配置sample grabber 以捕获数据。视频捕捉类ccapturevideo 的具体实现/ ccapturevideo 视频捕捉类头文件/#if !defined(afx_capturevideo_h_f5345aa4_a39f_4b07_b843_3d87c4287aa0 _included_)#defineafx_capturevideo_h_f5345aa4_a39f_4b07_b843_3d87c4287aa0_included_ / captu

24、revideo.h : header file/#if _msc_ver > 1000#pragma once#endif / _msc_ver > 1000#include <atlbase.h>#include <windows.h>#include <dshow.h>#ifndef safe_release#define safe_release( x ) if ( null != x ) x->release( ); x = null; #endifclass csamplegrabbercb;class ccapturevideo

25、 : public cwndfriend class csamplegrabbercb;public:void graboneframe(bool bgrab);hresult init(int ideviceid,hwnd hwnd);int enumdevices(hwnd hlist);ccapturevideo();virtual ccapturevideo();private:hwnd m_hwnd;igraphbuilder *m_pgb;icapturegraphbuilder2* m_pcapture;ibasefilter* m_pbf;imediacontrol* m_pm

26、c;ivideowindow* m_pvw;ccomptr<isamplegrabber> m_pgrabber;protected:void freemediatype(am_media_type& mt);bool bindfilter(int deviceid, ibasefilter *pfilter);void resizevideowindow();hresult setupvideowindow();hresult initcapturegraphbuilder();#endif/ !defined(afx_capturevideo_h_f5345aa4_a3

27、9f_4b07_b843_3d87c4287aa0_included_)/ ccapturevideo 视频捕捉类实现文件 capturevideo.cpp/ capturevideo.cpp: implementation of the ccapturevideo class./#include "stdafx.h"#include "capturevideo.h"#ifdef _debug#undef this_filestatic char this_file=_file_;#define new debug_new#endifbool bones

28、hot=false;/全局变量class csamplegrabbercb : public isamplegrabbercbpublic:long lwidth;long lheight;tchar m_szfilenamemax_path;位图文件名称csamplegrabbercb( )strcpy(m_szfilename, "c:donaldo.bmp");stdmethodimp_(ulong) addref() return 2; stdmethodimp_(ulong) release() return 1; stdmethodimp queryinterf

29、ace(refiid riid, void * ppv)if( riid = iid_isamplegrabbercb | riid = iid_iunknown )*ppv = (void *) static_cast<isamplegrabbercb*> ( this );return noerror;return e_nointerface;stdmethodimp samplecb( double sampletime, imediasample * psample ) return 0;stdmethodimp buffercb( double dblsampletime

30、, byte * pbuffer, long lbuffersize )if( !boneshot )return 0;if (!pbuffer)return e_pointer;savebitmap(pbuffer, lbuffersize);boneshot = false;return 0;/ 创建位图文件bool savebitmap(byte * pbuffer, long lbuffersize )handle hf = createfile(m_szfilename, generic_write, file_share_read, null,create_always, null

31、, null );if( hf = invalid_handle_value )return 0;/ 写文件头bitmapfileheader bfh;memset( &bfh, 0, sizeof( bfh ) );bfh.bftype = mb;bfh.bfsize = sizeof( bfh ) + lbuffersize + sizeof( bitmapinfohead)e; rbfh.bfoffbits = sizeof( bitmapinfoheader ) +sizeof( bitmapfileheader );dword dwwritten = 0;writefile(

32、 hf, &bfh, sizeof( bfh ), &dwwritten, null );/ 写位图格式bitmapinfoheader bih;memset( &bih, 0, sizeof( bih ) );bih.bisize = sizeof( bih );bih.biwidth = lwidth;bih.biheight = lheight;bih.biplanes = 1;bih.bibitcount = 24;writefile( hf, &bih, sizeof( bih ), &dwwritten, null );/ 写位图数据writ

33、efile( hf, pbuffer, lbuffersize, &dwwritten, null );closehandle( hf );return 0;csamplegrabbercb mcb;/ construction/destruction/ccapturevideo:ccapturevideo()/com library intializationif(failed(coinitialize(null) /*, coinit_apartmentthreaded)*/afxmessagebox("coinitialize failed!rn");retu

34、rn;m_hwnd = null;m_pvw = null;m_pmc = null;m_pgb = null;m_pcapture = null;ccapturevideo:ccapturevideo()/ stop media playbackif(m_pmc)m_pmc->stop();if(m_pvw)m_pvw->put_visible(oafalse);m_pvw->put_owner(null);safe_release(m_pcapture);safe_release(m_pmc);safe_release(m_pgb);safe_release(m_pbf)

35、;couninitialize( );int ccapturevideo:enumdevices(hwnd hlist)if (!hlist)return -1;int id = 0;/ 枚举视频扑捉设备icreatedevenum *pcreatedevenum;hresult hr = cocreateinstance(clsid_systemdeviceenum, null,clsctx_inproc_server,iid_icreatedevenum, (void*)&pcreatedevenum);if (hr != noerror)return -1;ccomptr<

36、ienummoniker> pem;hr =pcreatedevenum->createclassenumerator(clsid_videoinputdevicecategory, &pem, 0);if (hr != noerror)return -1;pem->reset();ulong cfetched;imoniker *pm;while(hr = pem->next(1, &pm, &cfetched), hr=s_ok)ipropertybag *pbag;hr = pm->bindtostorage(0, 0, iid_ip

37、ropertybag, (void *)&pbag); if(succeeded(hr)variant var;var.vt = vt_bstr;hr = pbag->read(l"friendlyname", &var, null);if (hr = noerror)tchar str2048;id+;widechartomultibyte(cp_acp,0,var.bstrval, -1, str, 2048, null, null);:sendmessage(hlist, cb_addstring, 0,(lparam)str);sysfrees

38、tring(var.bstrval);pbag->release();pm->release();return id;hresult ccapturevideo:init(int ideviceid, hwnd hwnd)hresult hr;hr = initcapturegraphbuilder();if (failed(hr)afxmessagebox("failed to get video interfaces!"); return hr;/ bind device filter. we know the device because the id w

39、as passed in if(!bindfilter(ideviceid, &m_pbf)return s_false;hr = m_pgb->addfilter(m_pbf, l"capture filter");/ hr = m_pcapture->renderstream(&pin_category_preview, &mediatype_video,/ m_pbf, null, null);/ create a sample grabberhr = m_pgrabber.cocreateinstance( clsid_sampl

40、egrabber );if( !m_pgrabber )afxmessagebox("fail to create samplegrabber, maybeqedit.dll is not registered?");return hr;ccomqiptr< ibasefilter, &iid_ibasefilter > pgrabbase( m_pgrabber );/ 设置视频格式am_media_type mt;zeromemory(&mt, sizeof(am_media_type);mt.majortype = mediatype_vi

41、deo;mt.subtype = mediasubtype_rgb24;hr = m_pgrabber->setmediatype(&mt);if( failed( hr ) )afxmessagebox("fail to set media type!");return hr;hr = m_pgb->addfilter( pgrabbase, l"grabber" );if( failed( hr ) )afxmessagebox("fail to put sample grabber in graph");re

42、turn hr;/ try to render preview/capture pinhr = m_pcapture->renderstream(&pin_category_preview, &mediatype_video,m_pbf,pgrabbase,null);if( failed( hr ) )hr = m_pcapture->renderstream(&pin_category_capture, &mediatype_video,m_pbf,pgrabbase,null);if( failed( hr ) )afxmessagebox(&

43、quot;can t build the graph");return hr;hr = m_pgrabber->getconnectedmediatype( &mt );if ( failed( hr) )afxmessagebox("failt to read the connected media type");return hr;videoinfoheader * vih = (videoinfoheader*) mt.pbformat;mcb.lwidth = vih->bmiheader.biwidth;mcb.lheight = v

44、ih->bmiheader.biheight;freemediatype(mt);hr = m_pgrabber->setbuffersamples( false );hr = m_pgrabber->setoneshot( false );hr = m_pgrabber->setcallback( &mcb, 1 );/ 设置视频捕捉窗口m_hwnd = hwnd ;setupvideowindow();hr = m_pmc->run();/ 开始视频捕捉if(failed(hr)afxmessagebox("couldn t run the

45、graph!");return hr; return s_ok;bool ccapturevideo:bindfilter(int deviceid, ibasefilter *pfilter)if (deviceid < 0) return false;/ enumerate all video capture devicesccomptr<icreatedevenum> pcreatedevenum;hresult hr = cocreateinstance(clsid_systemdeviceenum, null,clsctx_inproc_server,ii

46、d_icreatedevenum, (void*)&pcreatedevenum);if (hr != noerror)return false;ccomptr<ienummoniker> pem;hr =pcreatedevenum->createclassenumerator(clsid_videoinputdevicecategory, &pem, 0);if (hr != noerror)return false;pem->reset();ulong cfetched;imoniker *pm;int index = 0;while(hr = p

47、em->next(1, &pm, &cfetched), hr=s_ok, index <= deviceid)ipropertybag *pbag;hr = pm->bindtostorage(0, 0, iid_ipropertybag, (void *)&pbag); if(succeeded(hr)variant var;var.vt = vt_bstr;hr = pbag->read(l"friendlyname", &var, null);if (hr = noerror)if (index = devic

48、eid)pm->bindtoobject(0, 0, iid_ibasefilter, (void*)pfilter);sysfreestring(var.bstrval);pbag->release();pm->release();index+;return true;hresult ccapturevideo:initcapturegraphbuilder()hresult hr;/ 创建 igraphbuilder 接口hr=cocreateinstance(clsid_filtergraph, null, clsctx_inproc_server, iid_igrap

49、hbuilder, (void *)&m_pgb);/ 创建 icapturegraphbuilder2 接口hr = cocreateinstance (clsid_capturegraphbuilder2 , null,clsctx_inproc,iid_icapturegraphbuilder2, (void *) &m_pcapture);if (failed(hr)return hr;m_pcapture->setfiltergraph(m_pgb);hr = m_pgb->queryinterface(iid_imediacontrol, (void *)&m_pmc);if (failed(hr)return hr;hr = m_pgb->queryinterface(iid_ivideowindow, (lpvoid *) &m_pvw);if (failed(hr)return hr;return hr;hresult ccapturevideo:setupvideowindow()hr