【图像算法】彩色图像分割专题三:边缘检测+区域生长法
SkySeraph May 15th 2011 HQU
Email:[email protected] QQ:452728574
Latest Modified Date:May 15th 2011 HQU
一 原理:
空间转换:RGB转换为HSI http://www.cnblogs.com/skyseraph/archive/2011/05/03/2035643.html,结果见实现图1
边缘检测:在HSI空间,对HSI、H、S、I分别利用Canny进行边缘检测,结果见实现图2
区域生长:首先对边缘检测的图像沿边界进行质心计算,把求的的质心作为种子点;区域生长采用四领域像素聚类。
二 源码:
空间转换:http://www.cnblogs.com/skyseraph/archive/2011/05/05/2038317.html
边缘检测:
1 //////////////////////////////////////////////////////////////////////// //
2 // 寻找种子点(边缘检测法)
3 //////////////////////////////////////////////////////////////////////// //
4 void CColorSegDlg::OnCanny()
5 // Canny边缘检测
6 {
7 // 验证
8 if ( ! (ToDisplayCtr1))
9 {
10 MessageBox( " Please Load Pic! " );
11 return ;
12 }
13
14 if ( ! (ToDisplayCtr2 && ToDisplayCtr3 && ToDisplayCtr4 && ToDisplayCtr5))
15 {
16 MessageBox( " Please do SpaceConvetion! " );
17 return ;
18 }
19
20 UpdateData(TRUE);
21 int CANNY_T1,CANNY_T2; // canny算子双阈值
22 CANNY_T1 = m_CannyT1;
23 CANNY_T2 = m_CannyT2;
24
25 // 边缘检测图像的 "初始化"
26 ToDisplayCtr2Ed = cvCreateImage(cvGetSize(TheImage),IPL_DEPTH_8U, 1 );
27 ToDisplayCtr3Ed = cvCreateImage(cvGetSize(TheImage),IPL_DEPTH_8U, 1 );
28 ToDisplayCtr4Ed = cvCreateImage(cvGetSize(TheImage),IPL_DEPTH_8U, 1 );
29 ToDisplayCtr5Ed = cvCreateImage(cvGetSize(TheImage),IPL_DEPTH_8U, 1 );
30
31 ///////// /对各通道分量
32 // 定义工作位图并加载
33 IplImage * a;
34 a = ToDisplayCtr3;
35 IplImage * b;
36 b = ToDisplayCtr4;
37 IplImage * c;
38 c = ToDisplayCtr5;
39
40 // 定义辅助位图,描述边缘检测后图像
41 IplImage * aCanny = cvCreateImage(cvGetSize(a),IPL_DEPTH_8U, 1 );
42 IplImage * bCanny = cvCreateImage(cvGetSize(b),IPL_DEPTH_8U, 1 );
43 IplImage * cCanny = cvCreateImage(cvGetSize(c),IPL_DEPTH_8U, 1 );
44
45 // Canny边缘检测
46 // cvSobel(a,aCanny,1,0,3); // 水平sobel核
47 cvCanny(a, aCanny, CANNY_T1, CANNY_T2); // 阈值选择!
48 cvCanny(b, bCanny, CANNY_T1, CANNY_T2);
49 cvCanny(c, cCanny, CANNY_T1, CANNY_T2);
50
51 // 输出并显示
52 // imageReplace(aCanny,&ToDisplayCtr3);
53 // imageReplace(bCanny,&ToDisplayCtr4);
54 // imageReplace(cCanny,&ToDisplayCtr5);
55
56 cvCopyImage(aCanny,ToDisplayCtr3Ed); // 输出处理结果
57 cvCopyImage(bCanny,ToDisplayCtr4Ed);
58 cvCopyImage(cCanny,ToDisplayCtr5Ed);
59
60 DrawPicToHDC(ToDisplayCtr3Ed,IDC_ImgShowCtrl3); // 显示
61 DrawPicToHDC(ToDisplayCtr4Ed,IDC_ImgShowCtrl4);
62 DrawPicToHDC(ToDisplayCtr5Ed,IDC_ImgShowCtrl5);
63
64 // 释放资源
65 cvReleaseImage( & aCanny);
66 cvReleaseImage( & bCanny);
67 cvReleaseImage( & cCanny);
68
69
70 ///////// /对**空间图像
71 /// *
72 // 定义工作位图并加载
73 IplImage * dstColor;
74 dstColor = ToDisplayCtr2;
75 IplImage * dstGray = cvCreateImage(cvGetSize(dstColor),IPL_DEPTH_8U, 1 ); // cvCanny只接受单通道图像作为输入
76 cvCvtColor(dstColor,dstGray,CV_RGB2GRAY);
77
78 // 定义辅助位图,描述边缘检测后图像
79 IplImage * dstCannyGray = cvCreateImage(cvGetSize(dstGray),IPL_DEPTH_8U, 1 ); // cvCanny只接受单通道图像作为输入
80
81 // Canny边缘检测
82 cvCanny(dstGray,dstCannyGray,CANNY_T1,CANNY_T2);
83
84 // 输出并显示
85 cvCopyImage(dstCannyGray,ToDisplayCtr2Ed);
86 DrawPicToHDC(ToDisplayCtr2Ed,IDC_ImgShowCtrl2);
87
88 cvReleaseImage( & dstGray);
89 cvReleaseImage( & dstCannyGray);
90 // */
91
92 }
93
94 void CColorSegDlg::OnSeedsPoint()
95 {
96 // 验证
97 if ( ! (ToDisplayCtr1))
98 {
99 MessageBox( " Please Load Pic! " );
100 return ;
101 }
102
103 if ( ! (ToDisplayCtr2 && ToDisplayCtr3 && ToDisplayCtr4 && ToDisplayCtr5))
104 {
105 MessageBox( " Please do SpaceConvetion! " );
106 return ;
107 }
108
109 UpdateData(TRUE);
110
111 long seedNum = 0 ; // 种子点数
112 seed_Header = (seed_Node * )malloc( sizeof (seed_Node)); // 种子点,链表存贮
113
114 // 定义工作位图
115 IplImage * src ;
116 IplImage * srcCanny;
117 src = ToDisplayCtr2;
118
119 if (m_RGB == 0 ) // R
120 {
121 // src = ToDisplayCtr3;
122 srcCanny = ToDisplayCtr3Ed;
123 }
124
125 if (m_RGB == 1 ) // G
126 {
127 // src = ToDisplayCtr4;
128 srcCanny = ToDisplayCtr4Ed;
129 }
130
131 if (m_RGB == 2 ) // B
132 {
133 // src = ToDisplayCtr5;
134 srcCanny = ToDisplayCtr5Ed;
135 }
136
137 if (m_RGB == 3 ) // RGB
138 {
139 // src = ToDisplayCtr2;
140 srcCanny = ToDisplayCtr2Ed;
141 }
142
143 // 验证
144 if ( ! src && ! srcCanny)
145 {
146 MessageBox( " wrong! " );
147 return ;
148 }
149
150 // 定义辅助位图
151 IplImage * dst = NULL;
152 IplImage * dstCanny = NULL;
153
154 dst = cvCreateImage(cvGetSize(src),IPL_DEPTH_8U, 3 );
155 dstCanny = cvCreateImage(cvGetSize(srcCanny),IPL_DEPTH_8U, 1 );
156 /*
157 if(m_RGB == 3)
158 {
159 dst = cvCreateImage(cvGetSize(src),IPL_DEPTH_8U,3);
160 dstCanny = cvCreateImage(cvGetSize(srcCanny),IPL_DEPTH_8U,1);
161 }
162 else
163 {
164 dst = cvCreateImage(cvGetSize(src),IPL_DEPTH_8U,1);
165 dstCanny = cvCreateImage(cvGetSize(srcCanny),IPL_DEPTH_8U,1);
166 } */
167
168 cvCopyImage(src,dst);
169 cvCopyImage(srcCanny,dstCanny);
170 // dst = src;
171 // dstCanny = srcCanny;
172
173 // 寻找种子点
174 findSeed(dst,dstCanny,seed_Header,seedNum);
175
176 // cout<<seedNum<<endl;
177 m_SeedsPoint = seedNum;
178 UpdateData(FALSE);
179
180 cvReleaseImage( & dst);
181 cvReleaseImage( & dstCanny);
182 }
183
184 // 函数模块
185 // ----------------------------------------------- //
186 // 功能:寻找区域生长种子点
187 // 参数:dst 转换为**空间(如HSI)的彩色图像
188 // bundary 寻找的区域:hsi经canny边缘检测后的图像
189 // seed 种子点,链表存贮
190 // seedNUM 种子点数
191 // 返回:
192 // ----------------------------------------------- //
193 void CColorSegDlg::findSeed(IplImage * dst, IplImage * bundary, seed_Node * seed, long & seedNUM)
194 // 寻找种子点
195 {
196 int width = bundary -> width;
197 int height = bundary -> height;
198 bool * flag = ( bool * )malloc( sizeof ( bool ) * width * height); // 像素访问标记
199 bool first = true ;
200
201 memset(flag, 0 , sizeof ( bool ) * width * height);
202 seedNUM = 0 ;
203 seed_Node * seed_t = seed;
204
205 for ( int row = 0 ; row < height; row ++ ) // 列
206 for ( int col = 0 ; col < width; col ++ )
207 {
208 if (((uchar * )(bundary -> imageData +
209 row * bundary -> widthStep))[col * bundary -> nChannels] == 0 ) // 像素值==0
210 continue ;
211 if (flag[row * width + col]) // 已经访问过该点
212 continue ;
213 int X = 0 , Y = 0 , num = 0 ;
214 findBundary(bundary, flag, col, row, X, Y, num); // 得到区域重心
215 if (first)
216 {
217 first = false ;
218 }
219 else
220 {
221 seed_t -> next = (seed_Node * )malloc( sizeof (seed_Node));
222 seed_t = seed_t -> next;
223 }
224 seed_t -> x = X / num; // 增加新种子:质心/重心
225 seed_t -> y = Y / num;
226 seed_t -> next = NULL;
227
228 seed_t -> I = ((uchar * )(dst -> imageData + dst -> widthStep * row))[col * dst -> nChannels]; // 修改!
229 seed_t -> J = ((uchar * )(dst -> imageData + dst -> widthStep * row))[col * dst -> nChannels + 1 ];
230 seed_t -> K = ((uchar * )(dst -> imageData + dst -> widthStep * row))[col * dst -> nChannels + 2 ];
231 seed_t -> seedID = ++ seedNUM; // 种子点数加一
232 // segment[bundary->width*seed_t->y + seed_t->x] = seed_t->seedID;
233 }
234
235 free(flag);
236 }
237
238 // ----------------------------------------------- //
239 // 功能:沿边界递归寻找,计算区域重心/质心
240 // 参数:bundary寻找的区域
241 // flag 像素访问标记
242 // x/y 区域中的某点
243 // X/Y 质心/重心
244 // num 边界连接的像素数
245 // ----------------------------------------------- //
246 void CColorSegDlg::findBundary(IplImage * bundary, bool * flag, int x, int y
247 , int & X, int & Y, int & num)
248 // 获取区域重心
249 {
250 if (flag[y * bundary -> width + x]) // 像素已访问
251 return ;
252 if (((uchar * )(bundary -> imageData + y * bundary -> widthStep))[x * bundary -> nChannels] == 0 )
253 return ;
254 flag[y * bundary -> width + x] = true ; // 标记访问
255 X += x; // 质心X方向累加
256 Y += y;
257 num ++ ; // 边界连接的像素数加
258 for ( int i =- 1 ; i < 2 ; i ++ )
259 for ( int j =- 1 ; j < 2 ; j ++ ) // 八点领域扩散
260 {
261 if ( ! i && ! j) continue ;
262 if (x + j < 0 || x + j >= bundary -> width || y + i < 0 || y + i >= bundary -> height)
263 continue ;
264 findBundary(bundary, flag, x + j, y + i, X, Y, num); // 继续寻找
265 }
266 }
区域生长:
////////////////////////////////////////////////////////////////////////// // 区域生长(基于边缘检测提取种子点) ////////////////////////////////////////////////////////////////////////// // 区域生长 void CColorSegDlg::OnEdgeRegionGrowth() //消息响应 { // 验证 if(!(ToDisplayCtr1)) { MessageBox("Please Load Pic!"); return; } if(!(ToDisplayCtr2 && ToDisplayCtr3 && ToDisplayCtr4 && ToDisplayCtr5)) { MessageBox("Please do SpaceConvetion!"); return; } // 定义工作位图 IplImage* src ; IplImage* srcCanny; src = ToDisplayCtr2; // 判断 UpdateData(TRUE); if(m_RGB == 0) //R { //src = ToDisplayCtr3; srcCanny = ToDisplayCtr3Ed; } if(m_RGB == 1) //G { //src = ToDisplayCtr4; srcCanny = ToDisplayCtr4Ed; } if(m_RGB == 2) //B { //src = ToDisplayCtr5; srcCanny = ToDisplayCtr5Ed; } if(m_RGB == 3)//RGB { //src = ToDisplayCtr2; srcCanny = ToDisplayCtr2Ed; } // 验证 if(!src && ! srcCanny) { MessageBox("wrong!"); return; } // 定义辅助位图 IplImage* dst = NULL; IplImage* dstCanny = NULL; dst = cvCreateImage(cvGetSize(src),IPL_DEPTH_8U,3); dstCanny = cvCreateImage(cvGetSize(srcCanny),IPL_DEPTH_8U,1); cvCopyImage(src,dst); cvCopyImage(srcCanny,dstCanny); // 为分割结果申请空间 int width = TheImage->width; int height = TheImage->height; segment = (long *)malloc(sizeof(long)*width*height); memset(segment, 0, sizeof(long)*width*height); int TT; UpdateData(TRUE); TT = m_TT; // 区域生长 seed_Node *t_Node = seed_Header; while(t_Node) //基于种子点的区域生长 { regionGrowing(dst, dstCanny, t_Node, t_Node->x, t_Node->y, TT); t_Node = t_Node->next; } //////////分割结果 // SegResultImg "初始化" SegResultImg = cvCreateImage(cvGetSize(TheImage),IPL_DEPTH_8U,3); // 定义工作位图 IplImage* SegResultsrc; SegResultsrc = SegResultImg; // 定义辅助位图 IplImage* SegResultdst = cvCreateImage(cvGetSize(SegResultsrc),IPL_DEPTH_8U,3); IplImage* SegResultdstRGB = cvCreateImage(cvGetSize(SegResultsrc),IPL_DEPTH_8U,3); //print_segment(width, height); copy_segment(SegResultdst, seed_Header); //HSI2RGB(SegResultdst); //cvCvtColor(SegResultdst,SegResultdstRGB,CV_HSV2BGR); cvCopyImage(SegResultdst,SegResultImg); // cvNamedWindow("SegResultdstRGB result"); // cvShowImage("SegResultdstRGB result", SegResultdstRGB); cvNamedWindow("SegResultdst result"); cvShowImage("SegResultdst result", SegResultdst); //cvSaveImage("res.bmp", SegResultImg); cvDestroyWindow("segmentation result"); cvReleaseImage(&dst); cvReleaseImage(&dstCanny); } //-----------------------------------------------// uchar CColorSegDlg::color_distance(uchar h1, uchar h2) // 计算颜色距离 { if(h1<h2) return h2 - h1; return h1 - h2; } //-----------------------------------------------// //功能:区域生长 //参数:dst 转换为**空间(如HSI)的彩色图像 // bundary 区域:HSI经canny边缘检测后的图像 // seed 链表存贮的种子点 // xi/yi 种子点坐标 // T 相似性准则判断 的阈值 //返回: //-----------------------------------------------// void CColorSegDlg::regionGrowing(IplImage *dst, IplImage *bundary, seed_Node *seed, int xi, int yi, uchar T) // 区域生长 { int sp = 0; //栈顶指针 int width = dst->width; int height = dst->height; //int stuck[100]; int *stuck = (int *)malloc(sizeof(int)*width*height*2);//分配堆栈空间,存储种子点坐标 memset(stuck, 0, sizeof(int)*width*height*2); stuck[sp++] = xi; stuck[sp++] = yi; while(sp) { int y = stuck[--sp];//取出栈顶元素 int x = stuck[--sp]; //if(segment[bundary->width*y + x]!=0 ) // continue; // uchar a1 = ((uchar *)(dst->imageData + y*dst->widthStep))[dst->nChannels*x]; uchar b1 = ((uchar *)(dst->imageData + y*dst->widthStep))[dst->nChannels*x+1]; uchar c1 = ((uchar *)(dst->imageData + y*dst->widthStep))[dst->nChannels*x+2]; // uchar a2 = ((uchar *)(dst->imageData + seed->y*dst->widthStep))[dst->nChannels*seed->x]; uchar b2 = ((uchar *)(dst->imageData + seed->y*dst->widthStep))[dst->nChannels*seed->x+1]; uchar c2 = ((uchar *)(dst->imageData + seed->y*dst->widthStep))[dst->nChannels*seed->x+2]; // 判断两像素是否属于同一区域 if(color_distance(a1, a2) > T) continue; segment[bundary->width*y + x] = seed->seedID; // 重新计算区域颜色 /*seed->I /= 2; seed->I += a1/2; seed->J /= 2; seed->J += b1/2; seed->K /= 2; seed->K += c1/2;*/ seed->I = a2; seed->J = b2; seed->K = c2; for(int i=-1; i<2; i++) for(int j=-1; j<2; j++) //对四点领域做扩散 { if((i==-1&&j==-1) || (i==-1&&j==1) || (i==1&&j==-1) || (i==1&&j==1))//4领域 continue; if(i+y<0 || i+y>=dst->height || j+x<0 || j+x>=dst->width) continue; if(segment[bundary->width*(y+i) + x + j]!=0 ) continue; if(((uchar*)(bundary->imageData+bundary->widthStep*(y+i)))[bundary->nChannels*(x+j)] == 255) //到达边界,结束该方向的生长 continue; stuck[sp++] = x+j;//新种子点入栈 stuck[sp++] = y+i; segment[bundary->width*(y+i) + x + j] = -1; } } free(stuck); } //-----------------------------------------------// void CColorSegDlg::copy_segment(IplImage *pSeg, seed_Node *node) // 生成分割图 { int width = pSeg->width; int height = pSeg->height; for(int row=0; row<height; row++) for(int col=0; col<width; col++) { long id = segment[width*row+col]; seed_Node *t_node = node; uchar I, J, K; while(t_node) { if(t_node->seedID == id) //遍历确定像素所属的区域 { I = t_node->I; //分配像素颜色值 J = t_node->J; K = t_node->K; break; } t_node = t_node->next; } if(!t_node) continue; ((uchar *)(pSeg->imageData+row*pSeg->widthStep))[col*pSeg->nChannels] = I; ((uchar *)(pSeg->imageData+row*pSeg->widthStep))[col*pSeg->nChannels+1] = J; ((uchar *)(pSeg->imageData+row*pSeg->widthStep))[col*pSeg->nChannels+2] = K; } } void CColorSegDlg::print_segment(int width, int height) { for(int row=0; row<height; row++) { for(int col=0; col<width; col++) { //printf("%ld ", segment[width*row + col]); m_Test = segment[width*row + col]; UpdateData(false); } //printf("\n"); } } //////////////////////////////////////////////////////////////////////////
三 实现:
空间转换
边缘检测
提取种子点后区域生长结果
Author: SKySeraph
Email/GTalk: [email protected] QQ:452728574
From: http://www.cnblogs.com/skyseraph/
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