I use opencv for Face Detection,but when the code running,Picture frames go into a mess,see the picture,I think this error form FFMPEG, and opencv itself (may be the thread problem),Because I just open the camera, do not detect human face, the picture will not mess.

#include "cv.h"

include "highgui.h"

include <stdio.h>

include <stdlib.h>

include <string.h>

include <assert.h>

include <math.h>

include <float.h>

include <limits.h>

include <time.h>

include <ctype.h>

ifdef _EiC

define WIN32

endif

static CvMemStorage* storage = 0; static CvHaarClassifierCascade* cascade = 0;

void detect_and_draw( IplImage* image );

const char* cascade_name ="C:\Users\a\Desktop\opencv\sources\data\haarcascades\haarcascade_frontalface_alt.xml"; /* "haarcascade_profileface.xml";*/

int main( int argc, char* argv ) { CvCapture capture = cvCreateFileCapture("rtsp://192.168.1.108:554/cam/realmonitor?channel=1&subtype=0&unicast=true&proto=Onvif"); IplImage frame, *frame_copy = 0; int optlen = strlen("--cascade="); const char input_name;

if( argc > 1 && strncmp( argv[1], "--cascade=", optlen ) == 0 )
{
    cascade_name = argv[1] + optlen;
    input_name = argc > 2 ? argv[2] : 0;
}
else
{
    cascade_name = "C:\\Users\\a\\Desktop\\opencv\\sources\\data\\haarcascades\\haarcascade_frontalface_alt2.xml";
    //opencv装好后haarcascade_frontalface_alt2.xml的路径,
   //也可以把这个文件拷到你的工程文件夹下然后不用写路径名cascade_name= "haarcascade_frontalface_alt2.xml";  
   //或者cascade_name ="C:\\Program Files\\OpenCV\\data\\haarcascades\\haarcascade_frontalface_alt2.xml"
    input_name = argc > 1 ? argv[1] : 0;
}

cascade = (CvHaarClassifierCascade*)cvLoad( cascade_name, 0, 0, 0 );

if( !cascade )
{
    fprintf( stderr, "ERROR: Could not load classifier cascade\n" );
    fprintf( stderr,
    "Usage: facedetect --cascade=\"<cascade_path>\" [filename|camera_index]\n" );
    return -1;
}
storage = cvCreateMemStorage(0);

//if( !input_name || (isdigit(input_name[0]) && input_name[1] == '\0') )
   // capture = cvCaptureFromCAM( !input_name ? 0 : input_name[0] - '0' );

// else // capture = cvCaptureFromAVI( input_name );

cvNamedWindow( "result", 1 );

if( capture )
{
    for(;;)
    {
        if( !cvGrabFrame( capture ))
            break;
        frame = cvRetrieveFrame( capture );
        if( !frame )
            break;
        if( !frame_copy )
            frame_copy = cvCreateImage( cvSize(frame->width,frame->height),
                                        IPL_DEPTH_8U, frame->nChannels );
        if( frame->origin == IPL_ORIGIN_TL )
            cvCopy( frame, frame_copy, 0 );
        else
            cvFlip( frame, frame_copy, 0 );

        detect_and_draw( frame_copy );

        if( cvWaitKey( 10 ) >= 0 )
            break;
    }

    cvReleaseImage( &frame_copy );
    cvReleaseCapture( &capture );
}
else
{
    const char* filename = input_name ? input_name : (char*)"lena.jpg";
    IplImage* image = cvLoadImage( filename, 1 );

    if( image )
    {
        detect_and_draw( image );
        cvWaitKey(0);
        cvReleaseImage( &image );
    }
    else
    {
        /* assume it is a text file containing the
           list of the image filenames to be processed - one per line */
        FILE* f = fopen( filename, "rt" );
        if( f )
        {
            char buf[1000+1];
            while( fgets( buf, 1000, f ) )
            {
                int len = (int)strlen(buf);
                while( len > 0 && isspace(buf[len-1]) )
                    len--;
                buf[len] = '\0';
                image = cvLoadImage( buf, 1 );
                if( image )
                {
                    detect_and_draw( image );
                    cvWaitKey(0);
                    cvReleaseImage( &image );
                }
            }
            fclose(f);
        }
    }

}

cvDestroyWindow("result");

return 0;

}

void detect_and_draw( IplImage* img ) { static CvScalar colors[] = { {{0,0,255}}, {{0,128,255}}, {{0,255,255}}, {{0,255,0}}, {{255,128,0}}, {{255,255,0}}, {{255,0,0}}, {{255,0,255}} };

double scale = 1.3;
IplImage* gray = cvCreateImage( cvSize(img->width,img->height), 8, 1 );
IplImage* small_img = cvCreateImage( cvSize( cvRound (img->width/scale),
                     cvRound (img->height/scale)),
                 8, 1 );
int i;

cvCvtColor( img, gray, CV_BGR2GRAY );
cvResize( gray, small_img, CV_INTER_LINEAR );
cvEqualizeHist( small_img, small_img );
cvClearMemStorage( storage );

if( cascade )
{
    double t = (double)cvGetTickCount();
    CvSeq* faces = cvHaarDetectObjects( small_img, cascade, storage,
                                        1.1, 2, 0/*CV_HAAR_DO_CANNY_PRUNING*/,
                                        cvSize(30, 30) );
    t = (double)cvGetTickCount() - t;
    printf( "detection time = %gms\n", t/((double)cvGetTickFrequency()*1000.) );
    for( i = 0; i < (faces ? faces->total : 0); i++ )
    {
        CvRect* r = (CvRect*)cvGetSeqElem( faces, i );
        CvPoint center;
        int radius;
        center.x = cvRound((r->x + r->width*0.5)*scale);
        center.y = cvRound((r->y + r->height*0.5)*scale);
        radius = cvRound((r->width + r->height)*0.25*scale);
        cvCircle( img, center, radius, colors[i%8], 3, 8, 0 );
    }
}

cvShowImage( "result", img );
cvReleaseImage( &gray );
cvReleaseImage( &small_img );

}