霍夫變換原始碼

void cv::houghlines( inputarray _image, outputarray _lines,

double rho, double theta, int threshold,
double srn, double stn )
static
void seqtomat(const cvseq* seq, outputarray _arr)
else
_arr.release();
}cv_impl cvseq*
cvhoughlines2( cvarr* src_image, void* linestorage, int method,
double rho, double theta, int threshold,
double param1, double param2 )
else
if( cv_is_storage( linestorage ))
else
if( cv_is_mat( linestorage ))
else
cv_error( cv_stsbadarg, "destination is not cvmemstorage* nor cvmat*" );
iparam1 = cvround(param1);
iparam2 = cvround(param2);
switch( method )
if( mat )
else
result = lines;
return result;
}//標準霍夫變換
static
void
icvhoughlinesstandard( const cvmat* img, float rho, float theta,
int threshold, cvseq *lines, int linesmax )
// stage 1. fill accumulator
for( i = 0; i < height; i++ )
for( j = 0; j < width; j++ )
}// stage 2. 查詢區域性最大值
for(int r = 0; r < numrho; r++ )
for(int n = 0; n < numangle; n++ )
// stage 3. 按累加器的值對檢測的線進行排序
icvhoughsortdescent32s( sort_buf, total, accum );
// stage 4. store the first min(total,linesmax) lines to the output buffer
linesmax = min(linesmax, total);
scale = 1./(numrho+2);
for( i = 0; i < linesmax; i++ )
}//概率霍夫變換
static
void
icvhoughlinesprobabilistic( cvmat* image,
float rho, float theta, int threshold,
int linelength, int linegap,
cvseq *lines, int linesmax )
ttab = &trigtab[0];
mdata0 = mask.data;
cvstartwriteseq( cv_32sc2, sizeof(cvseq), sizeof(cvpoint), storage, &writer );//建立新序列並初始化寫入部分
// stage 1. collect non-zero image points
for( pt.y = 0, count = 0; pt.y < height; pt.y++ )
else
mdata[pt.x] = 0;}}
seq = cvendwriteseq( &writer ); //完成寫入操作
count = seq->total;
// stage 2. 隨機順序處理所有點
for( ; count > 0; count-- )
, };
float a, b;
int* adata = (int*)accum.data; //定義指向累加器指標
int i, j, k, x0, y0, dx0, dy0, xflag;
int good_line;
const
int shift = 16;
i = point->y;
j = point->x;
// "remove" it by overriding it with the last element
*point = *(cvpoint*)cvgetseqelem( seq, count-1 );
//檢查是否已被排除 (i.e. belongs to some other line)
if( !mdata0[i*width + j] )
continue;
// 更新累加器，找到最可能的線
for( n = 0; n < numangle; n++, adata += numrho )
}// if it is too "weak" candidate, continue with another point
if( max_val < threshold )
continue;
// from the current point walk in each direction
// 沿著找到的線並提取線段
a = -ttab[max_n*2+1];
b = ttab[max_n*2];
x0 = j;
y0 = i;
if( fabs(a) > fabs(b) )
else
for( k = 0; k < 2; k++ )
else
if( j1 < 0 || j1 >= width || i1 < 0 || i1 >= height )
break;
mdata = mdata0 + i1*width + j1;
// for each non-zero point:
//    update line end,
//    clear the mask element
//    reset the gap
if( *mdata )
else
if( ++gap > linegap )
break;}}
good_line = abs(line_end[1].x - line_end[0].x) >= linelength ||
abs(line_end[1].y - line_end[0].y) >= linelength;
for( k = 0; k < 2; k++ )
else
mdata = mdata0 + i1*width + j1;
// for each non-zero point:
//    update line end,
//    clear the mask element
//    reset the gap
if( *mdata )
}*mdata = 0;
}if( i1 == line_end[k].y && j1 == line_end[k].x )
break;}}
if( good_line )
;cvseqpush( lines, &lr );
if( lines->total >= linesmax )
return;}}
}

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