--- /dev/null
+/*M///////////////////////////////////////////////////////////////////////////////////////
+//
+// IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
+//
+// By downloading, copying, installing or using the software you agree to this license.
+// If you do not agree to this license, do not download, install,
+// copy or use the software.
+//
+//
+// Intel License Agreement
+// For Open Source Computer Vision Library
+//
+// Copyright (C) 2000, Intel Corporation, all rights reserved.
+// Third party copyrights are property of their respective owners.
+//
+// Redistribution and use in source and binary forms, with or without modification,
+// are permitted provided that the following conditions are met:
+//
+// * Redistribution's of source code must retain the above copyright notice,
+// this list of conditions and the following disclaimer.
+//
+// * Redistribution's in binary form must reproduce the above copyright notice,
+// this list of conditions and the following disclaimer in the documentation
+// and/or other materials provided with the distribution.
+//
+// * The name of Intel Corporation may not be used to endorse or promote products
+// derived from this software without specific prior written permission.
+//
+// This software is provided by the copyright holders and contributors "as is" and
+// any express or implied warranties, including, but not limited to, the implied
+// warranties of merchantability and fitness for a particular purpose are disclaimed.
+// In no event shall the Intel Corporation or contributors be liable for any direct,
+// indirect, incidental, special, exemplary, or consequential damages
+// (including, but not limited to, procurement of substitute goods or services;
+// loss of use, data, or profits; or business interruption) however caused
+// and on any theory of liability, whether in contract, strict liability,
+// or tort (including negligence or otherwise) arising in any way out of
+// the use of this software, even if advised of the possibility of such damage.
+//
+//M*/
+
+#include "_cv.h"
+
+static int
+icvSklansky_32s( CvPoint** array, int start, int end, int* stack, int nsign, int sign2 )
+{
+ int incr = end > start ? 1 : -1;
+ /* prepare first triangle */
+ int pprev = start, pcur = pprev + incr, pnext = pcur + incr;
+ int stacksize = 3;
+
+ if( start == end ||
+ (array[start]->x == array[end]->x &&
+ array[start]->y == array[end]->y) )
+ {
+ stack[0] = start;
+ return 1;
+ }
+
+ stack[0] = pprev;
+ stack[1] = pcur;
+ stack[2] = pnext;
+
+ end += incr; /* make end = afterend */
+
+ while( pnext != end )
+ {
+ /* check the angle p1,p2,p3 */
+ int cury = array[pcur]->y;
+ int nexty = array[pnext]->y;
+ int by = nexty - cury;
+
+ if( CV_SIGN(by) != nsign )
+ {
+ int ax = array[pcur]->x - array[pprev]->x;
+ int bx = array[pnext]->x - array[pcur]->x;
+ int ay = cury - array[pprev]->y;
+ int convexity = ay*bx - ax*by;/* if >0 then convex angle */
+
+ if( CV_SIGN(convexity) == sign2 && (ax != 0 || ay != 0) )
+ {
+ pprev = pcur;
+ pcur = pnext;
+ pnext += incr;
+ stack[stacksize] = pnext;
+ stacksize++;
+ }
+ else
+ {
+ if( pprev == start )
+ {
+ pcur = pnext;
+ stack[1] = pcur;
+ pnext += incr;
+ stack[2] = pnext;
+ }
+ else
+ {
+ stack[stacksize-2] = pnext;
+ pcur = pprev;
+ pprev = stack[stacksize-4];
+ stacksize--;
+ }
+ }
+ }
+ else
+ {
+ pnext += incr;
+ stack[stacksize-1] = pnext;
+ }
+ }
+
+ return --stacksize;
+}
+
+
+static int
+icvSklansky_32f( CvPoint2D32f** array, int start, int end, int* stack, int nsign, int sign2 )
+{
+ int incr = end > start ? 1 : -1;
+ /* prepare first triangle */
+ int pprev = start, pcur = pprev + incr, pnext = pcur + incr;
+ int stacksize = 3;
+
+ if( start == end ||
+ (array[start]->x == array[end]->x &&
+ array[start]->y == array[end]->y) )
+ {
+ stack[0] = start;
+ return 1;
+ }
+
+ stack[0] = pprev;
+ stack[1] = pcur;
+ stack[2] = pnext;
+
+ end += incr; /* make end = afterend */
+
+ while( pnext != end )
+ {
+ /* check the angle p1,p2,p3 */
+ float cury = array[pcur]->y;
+ float nexty = array[pnext]->y;
+ float by = nexty - cury;
+
+ if( CV_SIGN( by ) != nsign )
+ {
+ float ax = array[pcur]->x - array[pprev]->x;
+ float bx = array[pnext]->x - array[pcur]->x;
+ float ay = cury - array[pprev]->y;
+ float convexity = ay*bx - ax*by;/* if >0 then convex angle */
+
+ if( CV_SIGN( convexity ) == sign2 && (ax != 0 || ay != 0) )
+ {
+ pprev = pcur;
+ pcur = pnext;
+ pnext += incr;
+ stack[stacksize] = pnext;
+ stacksize++;
+ }
+ else
+ {
+ if( pprev == start )
+ {
+ pcur = pnext;
+ stack[1] = pcur;
+ pnext += incr;
+ stack[2] = pnext;
+
+ }
+ else
+ {
+ stack[stacksize-2] = pnext;
+ pcur = pprev;
+ pprev = stack[stacksize-4];
+ stacksize--;
+ }
+ }
+ }
+ else
+ {
+ pnext += incr;
+ stack[stacksize-1] = pnext;
+ }
+ }
+
+ return --stacksize;
+}
+
+typedef int (*sklansky_func)( CvPoint** points, int start, int end,
+ int* stack, int sign, int sign2 );
+
+#define cmp_pts( pt1, pt2 ) \
+ ((pt1)->x < (pt2)->x || ((pt1)->x <= (pt2)->x && (pt1)->y < (pt2)->y))
+static CV_IMPLEMENT_QSORT( icvSortPointsByPointers_32s, CvPoint*, cmp_pts )
+static CV_IMPLEMENT_QSORT( icvSortPointsByPointers_32f, CvPoint2D32f*, cmp_pts )
+
+static void
+icvCalcAndWritePtIndices( CvPoint** pointer, int* stack, int start, int end,
+ CvSeq* ptseq, CvSeqWriter* writer )
+{
+ CV_FUNCNAME( "icvCalcAndWritePtIndices" );
+
+ __BEGIN__;
+
+ int i, incr = start < end ? 1 : -1;
+ int idx, first_idx = ptseq->first->start_index;
+
+ for( i = start; i != end; i += incr )
+ {
+ CvPoint* ptr = (CvPoint*)pointer[stack[i]];
+ CvSeqBlock* block = ptseq->first;
+ while( (unsigned)(idx = (int)(ptr - (CvPoint*)block->data)) >= (unsigned)block->count )
+ {
+ block = block->next;
+ if( block == ptseq->first )
+ CV_ERROR( CV_StsError, "Internal error" );
+ }
+ idx += block->start_index - first_idx;
+ CV_WRITE_SEQ_ELEM( idx, *writer );
+ }
+
+ __END__;
+}
+
+
+CV_IMPL CvSeq*
+cvConvexHull2( const CvArr* array, void* hull_storage,
+ int orientation, int return_points )
+{
+ union { CvContour* c; CvSeq* s; } hull;
+ CvPoint** pointer = 0;
+ CvPoint2D32f** pointerf = 0;
+ int* stack = 0;
+
+ CV_FUNCNAME( "cvConvexHull2" );
+
+ hull.s = 0;
+
+ __BEGIN__;
+
+ CvMat* mat = 0;
+ CvSeqReader reader;
+ CvSeqWriter writer;
+ CvContour contour_header;
+ union { CvContour c; CvSeq s; } hull_header;
+ CvSeqBlock block, hullblock;
+ CvSeq* ptseq = 0;
+ CvSeq* hullseq = 0;
+ int is_float;
+ int* t_stack;
+ int t_count;
+ int i, miny_ind = 0, maxy_ind = 0, total;
+ int hulltype;
+ int stop_idx;
+ sklansky_func sklansky;
+
+ if( CV_IS_SEQ( array ))
+ {
+ ptseq = (CvSeq*)array;
+ if( !CV_IS_SEQ_POINT_SET( ptseq ))
+ CV_ERROR( CV_StsBadArg, "Unsupported sequence type" );
+ if( hull_storage == 0 )
+ hull_storage = ptseq->storage;
+ }
+ else
+ {
+ CV_CALL( ptseq = cvPointSeqFromMat(
+ CV_SEQ_KIND_GENERIC, array, &contour_header, &block ));
+ }
+
+ if( CV_IS_STORAGE( hull_storage ))
+ {
+ if( return_points )
+ {
+ CV_CALL( hullseq = cvCreateSeq(
+ CV_SEQ_KIND_CURVE|CV_SEQ_ELTYPE(ptseq)|
+ CV_SEQ_FLAG_CLOSED|CV_SEQ_FLAG_CONVEX,
+ sizeof(CvContour), sizeof(CvPoint),(CvMemStorage*)hull_storage ));
+ }
+ else
+ {
+ CV_CALL( hullseq = cvCreateSeq(
+ CV_SEQ_KIND_CURVE|CV_SEQ_ELTYPE_PPOINT|
+ CV_SEQ_FLAG_CLOSED|CV_SEQ_FLAG_CONVEX,
+ sizeof(CvContour), sizeof(CvPoint*), (CvMemStorage*)hull_storage ));
+ }
+ }
+ else
+ {
+ if( !CV_IS_MAT( hull_storage ))
+ CV_ERROR(CV_StsBadArg, "Destination must be valid memory storage or matrix");
+
+ mat = (CvMat*)hull_storage;
+
+ if( (mat->cols != 1 && mat->rows != 1) || !CV_IS_MAT_CONT(mat->type))
+ CV_ERROR( CV_StsBadArg,
+ "The hull matrix should be continuous and have a single row or a single column" );
+
+ if( mat->cols + mat->rows - 1 < ptseq->total )
+ CV_ERROR( CV_StsBadSize, "The hull matrix size might be not enough to fit the hull" );
+
+ if( CV_MAT_TYPE(mat->type) != CV_SEQ_ELTYPE(ptseq) &&
+ CV_MAT_TYPE(mat->type) != CV_32SC1 )
+ CV_ERROR( CV_StsUnsupportedFormat,
+ "The hull matrix must have the same type as input or 32sC1 (integers)" );
+
+ CV_CALL( hullseq = cvMakeSeqHeaderForArray(
+ CV_SEQ_KIND_CURVE|CV_MAT_TYPE(mat->type)|CV_SEQ_FLAG_CLOSED,
+ sizeof(contour_header), CV_ELEM_SIZE(mat->type), mat->data.ptr,
+ mat->cols + mat->rows - 1, &hull_header.s, &hullblock ));
+
+ cvClearSeq( hullseq );
+ }
+
+ total = ptseq->total;
+ if( total == 0 )
+ {
+ if( mat )
+ CV_ERROR( CV_StsBadSize,
+ "Point sequence can not be empty if the output is matrix" );
+ EXIT;
+ }
+
+ cvStartAppendToSeq( hullseq, &writer );
+
+ is_float = CV_SEQ_ELTYPE(ptseq) == CV_32FC2;
+ hulltype = CV_SEQ_ELTYPE(hullseq);
+ sklansky = !is_float ? (sklansky_func)icvSklansky_32s :
+ (sklansky_func)icvSklansky_32f;
+
+ CV_CALL( pointer = (CvPoint**)cvAlloc( ptseq->total*sizeof(pointer[0]) ));
+ CV_CALL( stack = (int*)cvAlloc( (ptseq->total + 2)*sizeof(stack[0]) ));
+ pointerf = (CvPoint2D32f**)pointer;
+
+ cvStartReadSeq( ptseq, &reader );
+
+ for( i = 0; i < total; i++ )
+ {
+ pointer[i] = (CvPoint*)reader.ptr;
+ CV_NEXT_SEQ_ELEM( ptseq->elem_size, reader );
+ }
+
+ // sort the point set by x-coordinate, find min and max y
+ if( !is_float )
+ {
+ icvSortPointsByPointers_32s( pointer, total, 0 );
+ for( i = 1; i < total; i++ )
+ {
+ int y = pointer[i]->y;
+ if( pointer[miny_ind]->y > y )
+ miny_ind = i;
+ if( pointer[maxy_ind]->y < y )
+ maxy_ind = i;
+ }
+ }
+ else
+ {
+ icvSortPointsByPointers_32f( pointerf, total, 0 );
+ for( i = 1; i < total; i++ )
+ {
+ float y = pointerf[i]->y;
+ if( pointerf[miny_ind]->y > y )
+ miny_ind = i;
+ if( pointerf[maxy_ind]->y < y )
+ maxy_ind = i;
+ }
+ }
+
+ if( pointer[0]->x == pointer[total-1]->x &&
+ pointer[0]->y == pointer[total-1]->y )
+ {
+ if( hulltype == CV_SEQ_ELTYPE_PPOINT )
+ {
+ CV_WRITE_SEQ_ELEM( pointer[0], writer );
+ }
+ else if( hulltype == CV_SEQ_ELTYPE_INDEX )
+ {
+ int index = 0;
+ CV_WRITE_SEQ_ELEM( index, writer );
+ }
+ else
+ {
+ CvPoint pt = pointer[0][0];
+ CV_WRITE_SEQ_ELEM( pt, writer );
+ }
+ goto finish_hull;
+ }
+
+ /*upper half */
+ {
+ int *tl_stack = stack;
+ int tl_count = sklansky( pointer, 0, maxy_ind, tl_stack, -1, 1 );
+ int *tr_stack = tl_stack + tl_count;
+ int tr_count = sklansky( pointer, ptseq->total - 1, maxy_ind, tr_stack, -1, -1 );
+
+ /* gather upper part of convex hull to output */
+ if( orientation == CV_COUNTER_CLOCKWISE )
+ {
+ CV_SWAP( tl_stack, tr_stack, t_stack );
+ CV_SWAP( tl_count, tr_count, t_count );
+ }
+
+ if( hulltype == CV_SEQ_ELTYPE_PPOINT )
+ {
+ for( i = 0; i < tl_count - 1; i++ )
+ CV_WRITE_SEQ_ELEM( pointer[tl_stack[i]], writer );
+
+ for( i = tr_count - 1; i > 0; i-- )
+ CV_WRITE_SEQ_ELEM( pointer[tr_stack[i]], writer );
+ }
+ else if( hulltype == CV_SEQ_ELTYPE_INDEX )
+ {
+ CV_CALL( icvCalcAndWritePtIndices( pointer, tl_stack,
+ 0, tl_count-1, ptseq, &writer ));
+ CV_CALL( icvCalcAndWritePtIndices( pointer, tr_stack,
+ tr_count-1, 0, ptseq, &writer ));
+ }
+ else
+ {
+ for( i = 0; i < tl_count - 1; i++ )
+ CV_WRITE_SEQ_ELEM( pointer[tl_stack[i]][0], writer );
+
+ for( i = tr_count - 1; i > 0; i-- )
+ CV_WRITE_SEQ_ELEM( pointer[tr_stack[i]][0], writer );
+ }
+ stop_idx = tr_count > 2 ? tr_stack[1] : tl_count > 2 ? tl_stack[tl_count - 2] : -1;
+ }
+
+ /* lower half */
+ {
+ int *bl_stack = stack;
+ int bl_count = sklansky( pointer, 0, miny_ind, bl_stack, 1, -1 );
+ int *br_stack = stack + bl_count;
+ int br_count = sklansky( pointer, ptseq->total - 1, miny_ind, br_stack, 1, 1 );
+
+ if( orientation != CV_COUNTER_CLOCKWISE )
+ {
+ CV_SWAP( bl_stack, br_stack, t_stack );
+ CV_SWAP( bl_count, br_count, t_count );
+ }
+
+ if( stop_idx >= 0 )
+ {
+ int check_idx = bl_count > 2 ? bl_stack[1] :
+ bl_count + br_count > 2 ? br_stack[2-bl_count] : -1;
+ if( check_idx == stop_idx || (check_idx >= 0 &&
+ pointer[check_idx]->x == pointer[stop_idx]->x &&
+ pointer[check_idx]->y == pointer[stop_idx]->y) )
+ {
+ /* if all the points lie on the same line, then
+ the bottom part of the convex hull is the mirrored top part
+ (except the exteme points).*/
+ bl_count = MIN( bl_count, 2 );
+ br_count = MIN( br_count, 2 );
+ }
+ }
+
+ if( hulltype == CV_SEQ_ELTYPE_PPOINT )
+ {
+ for( i = 0; i < bl_count - 1; i++ )
+ CV_WRITE_SEQ_ELEM( pointer[bl_stack[i]], writer );
+
+ for( i = br_count - 1; i > 0; i-- )
+ CV_WRITE_SEQ_ELEM( pointer[br_stack[i]], writer );
+ }
+ else if( hulltype == CV_SEQ_ELTYPE_INDEX )
+ {
+ CV_CALL( icvCalcAndWritePtIndices( pointer, bl_stack,
+ 0, bl_count-1, ptseq, &writer ));
+ CV_CALL( icvCalcAndWritePtIndices( pointer, br_stack,
+ br_count-1, 0, ptseq, &writer ));
+ }
+ else
+ {
+ for( i = 0; i < bl_count - 1; i++ )
+ CV_WRITE_SEQ_ELEM( pointer[bl_stack[i]][0], writer );
+
+ for( i = br_count - 1; i > 0; i-- )
+ CV_WRITE_SEQ_ELEM( pointer[br_stack[i]][0], writer );
+ }
+ }
+
+finish_hull:
+ CV_CALL( cvEndWriteSeq( &writer ));
+
+ if( mat )
+ {
+ if( mat->rows > mat->cols )
+ mat->rows = hullseq->total;
+ else
+ mat->cols = hullseq->total;
+ }
+ else
+ {
+ hull.s = hullseq;
+ hull.c->rect = cvBoundingRect( ptseq,
+ ptseq->header_size < (int)sizeof(CvContour) ||
+ &ptseq->flags == &contour_header.flags );
+
+ /*if( ptseq != (CvSeq*)&contour_header )
+ hullseq->v_prev = ptseq;*/
+ }
+
+ __END__;
+
+ cvFree( &pointer );
+ cvFree( &stack );
+
+ return hull.s;
+}
+
+
+/* contour must be a simple polygon */
+/* it must have more than 3 points */
+CV_IMPL CvSeq*
+cvConvexityDefects( const CvArr* array,
+ const CvArr* hullarray,
+ CvMemStorage* storage )
+{
+ CvSeq* defects = 0;
+
+ CV_FUNCNAME( "cvConvexityDefects" );
+
+ __BEGIN__;
+
+ int i, index;
+ CvPoint* hull_cur;
+
+ /* is orientation of hull different from contour one */
+ int rev_orientation;
+
+ CvContour contour_header;
+ union { CvContour c; CvSeq s; } hull_header;
+ CvSeqBlock block, hullblock;
+ CvSeq *ptseq = (CvSeq*)array, *hull = (CvSeq*)hullarray;
+
+ CvSeqReader hull_reader;
+ CvSeqReader ptseq_reader;
+ CvSeqWriter writer;
+ int is_index;
+
+ if( CV_IS_SEQ( ptseq ))
+ {
+ if( !CV_IS_SEQ_POINT_SET( ptseq ))
+ CV_ERROR( CV_StsUnsupportedFormat,
+ "Input sequence is not a sequence of points" );
+ if( !storage )
+ storage = ptseq->storage;
+ }
+ else
+ {
+ CV_CALL( ptseq = cvPointSeqFromMat(
+ CV_SEQ_KIND_GENERIC, array, &contour_header, &block ));
+ }
+
+ if( CV_SEQ_ELTYPE( ptseq ) != CV_32SC2 )
+ CV_ERROR( CV_StsUnsupportedFormat,
+ "Floating-point coordinates are not supported here" );
+
+ if( CV_IS_SEQ( hull ))
+ {
+ int hulltype = CV_SEQ_ELTYPE( hull );
+ if( hulltype != CV_SEQ_ELTYPE_PPOINT && hulltype != CV_SEQ_ELTYPE_INDEX )
+ CV_ERROR( CV_StsUnsupportedFormat,
+ "Convex hull must represented as a sequence "
+ "of indices or sequence of pointers" );
+ if( !storage )
+ storage = hull->storage;
+ }
+ else
+ {
+ CvMat* mat = (CvMat*)hull;
+
+ if( !CV_IS_MAT( hull ))
+ CV_ERROR(CV_StsBadArg, "Convex hull is neither sequence nor matrix");
+
+ if( (mat->cols != 1 && mat->rows != 1) ||
+ !CV_IS_MAT_CONT(mat->type) || CV_MAT_TYPE(mat->type) != CV_32SC1 )
+ CV_ERROR( CV_StsBadArg,
+ "The matrix should be 1-dimensional and continuous array of int's" );
+
+ if( mat->cols + mat->rows - 1 > ptseq->total )
+ CV_ERROR( CV_StsBadSize, "Convex hull is larger than the point sequence" );
+
+ CV_CALL( hull = cvMakeSeqHeaderForArray(
+ CV_SEQ_KIND_CURVE|CV_MAT_TYPE(mat->type)|CV_SEQ_FLAG_CLOSED,
+ sizeof(CvContour), CV_ELEM_SIZE(mat->type), mat->data.ptr,
+ mat->cols + mat->rows - 1, &hull_header.s, &hullblock ));
+ }
+
+ is_index = CV_SEQ_ELTYPE(hull) == CV_SEQ_ELTYPE_INDEX;
+
+ if( !storage )
+ CV_ERROR( CV_StsNullPtr, "NULL storage pointer" );
+
+ CV_CALL( defects = cvCreateSeq( CV_SEQ_KIND_GENERIC, sizeof(CvSeq),
+ sizeof(CvConvexityDefect), storage ));
+
+ if( ptseq->total < 4 || hull->total < 3)
+ {
+ //CV_ERROR( CV_StsBadSize,
+ // "point seq size must be >= 4, convex hull size must be >= 3" );
+ EXIT;
+ }
+
+ /* recognize co-orientation of ptseq and its hull */
+ {
+ int sign = 0;
+ int index1, index2, index3;
+
+ if( !is_index )
+ {
+ CvPoint* pos = *CV_SEQ_ELEM( hull, CvPoint*, 0 );
+ CV_CALL( index1 = cvSeqElemIdx( ptseq, pos ));
+
+ pos = *CV_SEQ_ELEM( hull, CvPoint*, 1 );
+ CV_CALL( index2 = cvSeqElemIdx( ptseq, pos ));
+
+ pos = *CV_SEQ_ELEM( hull, CvPoint*, 2 );
+ CV_CALL( index3 = cvSeqElemIdx( ptseq, pos ));
+ }
+ else
+ {
+ index1 = *CV_SEQ_ELEM( hull, int, 0 );
+ index2 = *CV_SEQ_ELEM( hull, int, 1 );
+ index3 = *CV_SEQ_ELEM( hull, int, 2 );
+ }
+
+ sign += (index2 > index1) ? 1 : 0;
+ sign += (index3 > index2) ? 1 : 0;
+ sign += (index1 > index3) ? 1 : 0;
+
+ rev_orientation = (sign == 2) ? 0 : 1;
+ }
+
+ cvStartReadSeq( ptseq, &ptseq_reader, 0 );
+ cvStartReadSeq( hull, &hull_reader, rev_orientation );
+
+ if( !is_index )
+ {
+ hull_cur = *(CvPoint**)hull_reader.prev_elem;
+ index = cvSeqElemIdx( ptseq, (char*)hull_cur, 0 );
+ }
+ else
+ {
+ index = *(int*)hull_reader.prev_elem;
+ hull_cur = CV_GET_SEQ_ELEM( CvPoint, ptseq, index );
+ }
+ cvSetSeqReaderPos( &ptseq_reader, index );
+ cvStartAppendToSeq( defects, &writer );
+
+ /* cycle through ptseq and hull with computing defects */
+ for( i = 0; i < hull->total; i++ )
+ {
+ CvConvexityDefect defect;
+ int is_defect = 0;
+ double dx0, dy0;
+ double depth = 0, scale;
+ CvPoint* hull_next;
+
+ if( !is_index )
+ hull_next = *(CvPoint**)hull_reader.ptr;
+ else
+ {
+ int t = *(int*)hull_reader.ptr;
+ hull_next = CV_GET_SEQ_ELEM( CvPoint, ptseq, t );
+ }
+
+ dx0 = (double)hull_next->x - (double)hull_cur->x;
+ dy0 = (double)hull_next->y - (double)hull_cur->y;
+ assert( dx0 != 0 || dy0 != 0 );
+ scale = 1./sqrt(dx0*dx0 + dy0*dy0);
+
+ defect.start = hull_cur;
+ defect.end = hull_next;
+
+ for(;;)
+ {
+ /* go through ptseq to achieve next hull point */
+ CV_NEXT_SEQ_ELEM( sizeof(CvPoint), ptseq_reader );
+
+ if( ptseq_reader.ptr == (schar*)hull_next )
+ break;
+ else
+ {
+ CvPoint* cur = (CvPoint*)ptseq_reader.ptr;
+
+ /* compute distance from current point to hull edge */
+ double dx = (double)cur->x - (double)hull_cur->x;
+ double dy = (double)cur->y - (double)hull_cur->y;
+
+ /* compute depth */
+ double dist = fabs(-dy0*dx + dx0*dy) * scale;
+
+ if( dist > depth )
+ {
+ depth = dist;
+ defect.depth_point = cur;
+ defect.depth = (float)depth;
+ is_defect = 1;
+ }
+ }
+ }
+ if( is_defect )
+ {
+ CV_WRITE_SEQ_ELEM( defect, writer );
+ }
+
+ hull_cur = hull_next;
+ if( rev_orientation )
+ {
+ CV_PREV_SEQ_ELEM( hull->elem_size, hull_reader );
+ }
+ else
+ {
+ CV_NEXT_SEQ_ELEM( hull->elem_size, hull_reader );
+ }
+ }
+
+ defects = cvEndWriteSeq( &writer );
+
+ __END__;
+
+ return defects;
+}
+
+
+CV_IMPL int
+cvCheckContourConvexity( const CvArr* array )
+{
+ int flag = -1;
+
+ CV_FUNCNAME( "cvCheckContourConvexity" );
+
+ __BEGIN__;
+
+ int i;
+ int orientation = 0;
+ CvSeqReader reader;
+ CvContour contour_header;
+ CvSeqBlock block;
+ CvSeq* contour = (CvSeq*)array;
+
+ if( CV_IS_SEQ(contour) )
+ {
+ if( !CV_IS_SEQ_POINT_SET(contour))
+ CV_ERROR( CV_StsUnsupportedFormat,
+ "Input sequence must be polygon (closed 2d curve)" );
+ }
+ else
+ {
+ CV_CALL( contour = cvPointSeqFromMat(
+ CV_SEQ_KIND_CURVE|CV_SEQ_FLAG_CLOSED, array, &contour_header, &block ));
+ }
+
+ if( contour->total == 0 )
+ EXIT;
+
+ cvStartReadSeq( contour, &reader, 0 );
+
+ flag = 1;
+
+ if( CV_SEQ_ELTYPE( contour ) == CV_32SC2 )
+ {
+ CvPoint *prev_pt = (CvPoint*)reader.prev_elem;
+ CvPoint *cur_pt = (CvPoint*)reader.ptr;
+
+ int dx0 = cur_pt->x - prev_pt->x;
+ int dy0 = cur_pt->y - prev_pt->y;
+
+ for( i = 0; i < contour->total; i++ )
+ {
+ int dxdy0, dydx0;
+ int dx, dy;
+
+ /*int orient; */
+ CV_NEXT_SEQ_ELEM( sizeof(CvPoint), reader );
+ prev_pt = cur_pt;
+ cur_pt = (CvPoint *) reader.ptr;
+
+ dx = cur_pt->x - prev_pt->x;
+ dy = cur_pt->y - prev_pt->y;
+ dxdy0 = dx * dy0;
+ dydx0 = dy * dx0;
+
+ /* find orientation */
+ /*orient = -dy0 * dx + dx0 * dy;
+ orientation |= (orient > 0) ? 1 : 2;
+ */
+ orientation |= (dydx0 > dxdy0) ? 1 : ((dydx0 < dxdy0) ? 2 : 3);
+
+ if( orientation == 3 )
+ {
+ flag = 0;
+ break;
+ }
+
+ dx0 = dx;
+ dy0 = dy;
+ }
+ }
+ else
+ {
+ assert( CV_SEQ_ELTYPE(contour) == CV_32FC2 );
+
+ CvPoint2D32f *prev_pt = (CvPoint2D32f*)reader.prev_elem;
+ CvPoint2D32f *cur_pt = (CvPoint2D32f*)reader.ptr;
+
+ float dx0 = cur_pt->x - prev_pt->x;
+ float dy0 = cur_pt->y - prev_pt->y;
+
+ for( i = 0; i < contour->total; i++ )
+ {
+ float dxdy0, dydx0;
+ float dx, dy;
+
+ /*int orient; */
+ CV_NEXT_SEQ_ELEM( sizeof(CvPoint2D32f), reader );
+ prev_pt = cur_pt;
+ cur_pt = (CvPoint2D32f*) reader.ptr;
+
+ dx = cur_pt->x - prev_pt->x;
+ dy = cur_pt->y - prev_pt->y;
+ dxdy0 = dx * dy0;
+ dydx0 = dy * dx0;
+
+ /* find orientation */
+ /*orient = -dy0 * dx + dx0 * dy;
+ orientation |= (orient > 0) ? 1 : 2;
+ */
+ orientation |= (dydx0 > dxdy0) ? 1 : ((dydx0 < dxdy0) ? 2 : 3);
+
+ if( orientation == 3 )
+ {
+ flag = 0;
+ break;
+ }
+
+ dx0 = dx;
+ dy0 = dy;
+ }
+ }
+
+ __END__;
+
+ return flag;
+}
+
+
+/* End of file. */
projects / opencv / blobdiff