【OpenCV學習】cvseqpartition序列分類

作者：gnuhpc
出處：http://www.cnblogs.com/gnuhpc/

#include "cxcore.h"#include "highgui.h"#include <stdio.h>CvSeq* point_seq = 0;IplImage* canvas = 0;CvScalar* colors = 0;int pos = 10;int is_equal( const void* _a, const void* _b, void* userdata ){CvPoint a = *(const CvPoint*)_a;CvPoint b = *(const CvPoint*)_b;double threshold = *(double*)userdata;return (double)(a.x - b.x)*(a.x - b.x) + (double)(a.y - b.y)*(a.y - b.y) <= threshold;}void on_track( int pos ){CvSeq* labels = 0; //聲明輸出標籤double threshold = pos*pos; //定義閾值為pos^2int i, class_count = cvSeqPartition( point_seq, 0, &labels, is_equal, &threshold );//對point_seq點序列拆分為等效的類，條件是(Ax-Bx)^2+(Ay-By)^2<=pos^2//含義為兩點相差距離小於pos的屬於一類printf("%4d classes/n", class_count );//列印出分了幾類cvZero( canvas );for( i = 0; i < labels->total; i++ ){//取點、取顏色，畫圓,你可以用按任意鍵的方式一個點一個點的畫CvPoint pt = *(CvPoint*)cvGetSeqElem( point_seq, i );CvScalar color = colors[*(int*)cvGetSeqElem( labels, i )];cvCircle( canvas, pt, 1, color, -1 );cvShowImage( "points", canvas );cvWaitKey(0);}}int main( int argc, char** argv ){CvMemStorage* storage = cvCreateMemStorage(0);//建立了一個儲存空間point_seq = cvCreateSeq( CV_32SC2, sizeof(CvSeq), sizeof(CvPoint), storage );//建立了一個32位整型序列CvRNG rng = cvRNG(0xffffffff);//初始化隨機數產生器int width = 500, height = 500;//定義映像的長和寬int i, count = 1000;//定義了兩個計數器canvas = cvCreateImage( cvSize(width,height), 8, 3 );//設定映像，大小為500*500，色深8，三通道colors = (CvScalar*)cvAlloc( count*sizeof(colors[0]) );//分配1000個CvScalar大小的記憶體緩衝區for( i = 0; i < count; i++ ){CvPoint pt;//設定一個點int icolor;//定義顏色標的pt.x = cvRandInt( &rng ) % width;//隨機產生點的x座標pt.y = cvRandInt( &rng ) % height;//隨機產生點的y座標cvSeqPush( point_seq, &pt );//添加這個點到序列的尾部icolor = cvRandInt( &rng ) +0xa0a0a0a0 ;//用隨機的方法給顏色標的一個基準，後邊加的那個數字是可以任意的。colors[i] = CV_RGB(icolor & 255, (icolor >> 8)&255, (icolor >> 16)&255);//把這個點的顏色完全寫入標量容器colors中}cvNamedWindow( "points", 1 );//建立視窗cvCreateTrackbar( "threshold", "points", &pos, 50, on_track );//建立拖動條，名稱為threshold，視窗的名字叫points，建立初始化值取自pos，//回呼函數名稱為on_trackon_track(pos);//監視拖動條的改變並處理之cvWaitKey(0);return 0;} 

作者：gnuhpc

出處：http://www.cnblogs.com/gnuhpc/