+++ /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"
-
-/* initializes 8-element array for fast access to 3x3 neighborhood of a pixel */
-#define CV_INIT_3X3_DELTAS( deltas, step, nch ) \
- ((deltas)[0] = (nch), (deltas)[1] = -(step) + (nch), \
- (deltas)[2] = -(step), (deltas)[3] = -(step) - (nch), \
- (deltas)[4] = -(nch), (deltas)[5] = (step) - (nch), \
- (deltas)[6] = (step), (deltas)[7] = (step) + (nch))
-
-static const CvPoint icvCodeDeltas[8] =
- { {1, 0}, {1, -1}, {0, -1}, {-1, -1}, {-1, 0}, {-1, 1}, {0, 1}, {1, 1} };
-
-CV_IMPL void
-cvStartReadChainPoints( CvChain * chain, CvChainPtReader * reader )
-{
- int i;
-
- CV_FUNCNAME( "cvStartReadChainPoints" );
-
- __BEGIN__;
-
- if( !chain || !reader )
- CV_ERROR( CV_StsNullPtr, "" );
-
- if( chain->elem_size != 1 || chain->header_size < (int)sizeof(CvChain))
- CV_ERROR_FROM_STATUS( CV_BADSIZE_ERR );
-
- cvStartReadSeq( (CvSeq *) chain, (CvSeqReader *) reader, 0 );
- CV_CHECK();
-
- reader->pt = chain->origin;
-
- for( i = 0; i < 8; i++ )
- {
- reader->deltas[i][0] = (schar) icvCodeDeltas[i].x;
- reader->deltas[i][1] = (schar) icvCodeDeltas[i].y;
- }
-
- __END__;
-}
-
-
-/* retrieves next point of the chain curve and updates reader */
-CV_IMPL CvPoint
-cvReadChainPoint( CvChainPtReader * reader )
-{
- schar *ptr;
- int code;
- CvPoint pt = { 0, 0 };
-
- CV_FUNCNAME( "cvReadChainPoint" );
-
- __BEGIN__;
-
- if( !reader )
- CV_ERROR( CV_StsNullPtr, "" );
-
- pt = reader->pt;
-
- ptr = reader->ptr;
- if( ptr )
- {
- code = *ptr++;
-
- if( ptr >= reader->block_max )
- {
- cvChangeSeqBlock( (CvSeqReader *) reader, 1 );
- ptr = reader->ptr;
- }
-
- reader->ptr = ptr;
- reader->code = (schar)code;
- assert( (code & ~7) == 0 );
- reader->pt.x = pt.x + icvCodeDeltas[code].x;
- reader->pt.y = pt.y + icvCodeDeltas[code].y;
- }
-
- __END__;
-
- return pt;
-}
-
-
-/****************************************************************************************\
-* Raster->Chain Tree (Suzuki algorithms) *
-\****************************************************************************************/
-
-typedef struct _CvContourInfo
-{
- int flags;
- struct _CvContourInfo *next; /* next contour with the same mark value */
- struct _CvContourInfo *parent; /* information about parent contour */
- CvSeq *contour; /* corresponding contour (may be 0, if rejected) */
- CvRect rect; /* bounding rectangle */
- CvPoint origin; /* origin point (where the contour was traced from) */
- int is_hole; /* hole flag */
-}
-_CvContourInfo;
-
-
-/*
- Structure that is used for sequental retrieving contours from the image.
- It supports both hierarchical and plane variants of Suzuki algorithm.
-*/
-typedef struct _CvContourScanner
-{
- CvMemStorage *storage1; /* contains fetched contours */
- CvMemStorage *storage2; /* contains approximated contours
- (!=storage1 if approx_method2 != approx_method1) */
- CvMemStorage *cinfo_storage; /* contains _CvContourInfo nodes */
- CvSet *cinfo_set; /* set of _CvContourInfo nodes */
- CvMemStoragePos initial_pos; /* starting storage pos */
- CvMemStoragePos backup_pos; /* beginning of the latest approx. contour */
- CvMemStoragePos backup_pos2; /* ending of the latest approx. contour */
- schar *img0; /* image origin */
- schar *img; /* current image row */
- int img_step; /* image step */
- CvSize img_size; /* ROI size */
- CvPoint offset; /* ROI offset: coordinates, added to each contour point */
- CvPoint pt; /* current scanner position */
- CvPoint lnbd; /* position of the last met contour */
- int nbd; /* current mark val */
- _CvContourInfo *l_cinfo; /* information about latest approx. contour */
- _CvContourInfo cinfo_temp; /* temporary var which is used in simple modes */
- _CvContourInfo frame_info; /* information about frame */
- CvSeq frame; /* frame itself */
- int approx_method1; /* approx method when tracing */
- int approx_method2; /* final approx method */
- int mode; /* contour scanning mode:
- 0 - external only
- 1 - all the contours w/o any hierarchy
- 2 - connected components (i.e. two-level structure -
- external contours and holes) */
- int subst_flag;
- int seq_type1; /* type of fetched contours */
- int header_size1; /* hdr size of fetched contours */
- int elem_size1; /* elem size of fetched contours */
- int seq_type2; /* */
- int header_size2; /* the same for approx. contours */
- int elem_size2; /* */
- _CvContourInfo *cinfo_table[126];
-}
-_CvContourScanner;
-
-#define _CV_FIND_CONTOURS_FLAGS_EXTERNAL_ONLY 1
-#define _CV_FIND_CONTOURS_FLAGS_HIERARCHIC 2
-
-/*
- Initializes scanner structure.
- Prepare image for scanning ( clear borders and convert all pixels to 0-1.
-*/
-CV_IMPL CvContourScanner
-cvStartFindContours( void* _img, CvMemStorage* storage,
- int header_size, int mode,
- int method, CvPoint offset )
-{
- int y;
- int step;
- CvSize size;
- uchar *img = 0;
- CvContourScanner scanner = 0;
- CvMat stub, *mat = (CvMat*)_img;
-
- CV_FUNCNAME( "cvStartFindContours" );
-
- __BEGIN__;
-
- if( !storage )
- CV_ERROR( CV_StsNullPtr, "" );
-
- CV_CALL( mat = cvGetMat( mat, &stub ));
-
- if( !CV_IS_MASK_ARR( mat ))
- CV_ERROR( CV_StsUnsupportedFormat, "[Start]FindContours support only 8uC1 images" );
-
- size = cvSize( mat->width, mat->height );
- step = mat->step;
- img = (uchar*)(mat->data.ptr);
-
- if( method < 0 || method > CV_CHAIN_APPROX_TC89_KCOS )
- CV_ERROR_FROM_STATUS( CV_BADRANGE_ERR );
-
- if( header_size < (int) (method == CV_CHAIN_CODE ? sizeof( CvChain ) : sizeof( CvContour )))
- CV_ERROR_FROM_STATUS( CV_BADSIZE_ERR );
-
- scanner = (CvContourScanner)cvAlloc( sizeof( *scanner ));
- if( !scanner )
- CV_ERROR_FROM_STATUS( CV_OUTOFMEM_ERR );
-
- memset( scanner, 0, sizeof( *scanner ));
-
- scanner->storage1 = scanner->storage2 = storage;
- scanner->img0 = (schar *) img;
- scanner->img = (schar *) (img + step);
- scanner->img_step = step;
- scanner->img_size.width = size.width - 1; /* exclude rightest column */
- scanner->img_size.height = size.height - 1; /* exclude bottomost row */
- scanner->mode = mode;
- scanner->offset = offset;
- scanner->pt.x = scanner->pt.y = 1;
- scanner->lnbd.x = 0;
- scanner->lnbd.y = 1;
- scanner->nbd = 2;
- scanner->mode = (int) mode;
- scanner->frame_info.contour = &(scanner->frame);
- scanner->frame_info.is_hole = 1;
- scanner->frame_info.next = 0;
- scanner->frame_info.parent = 0;
- scanner->frame_info.rect = cvRect( 0, 0, size.width, size.height );
- scanner->l_cinfo = 0;
- scanner->subst_flag = 0;
-
- scanner->frame.flags = CV_SEQ_FLAG_HOLE;
-
- scanner->approx_method2 = scanner->approx_method1 = method;
-
- if( method == CV_CHAIN_APPROX_TC89_L1 || method == CV_CHAIN_APPROX_TC89_KCOS )
- scanner->approx_method1 = CV_CHAIN_CODE;
-
- if( scanner->approx_method1 == CV_CHAIN_CODE )
- {
- scanner->seq_type1 = CV_SEQ_CHAIN_CONTOUR;
- scanner->header_size1 = scanner->approx_method1 == scanner->approx_method2 ?
- header_size : sizeof( CvChain );
- scanner->elem_size1 = sizeof( char );
- }
- else
- {
- scanner->seq_type1 = CV_SEQ_POLYGON;
- scanner->header_size1 = scanner->approx_method1 == scanner->approx_method2 ?
- header_size : sizeof( CvContour );
- scanner->elem_size1 = sizeof( CvPoint );
- }
-
- scanner->header_size2 = header_size;
-
- if( scanner->approx_method2 == CV_CHAIN_CODE )
- {
- scanner->seq_type2 = scanner->seq_type1;
- scanner->elem_size2 = scanner->elem_size1;
- }
- else
- {
- scanner->seq_type2 = CV_SEQ_POLYGON;
- scanner->elem_size2 = sizeof( CvPoint );
- }
-
- scanner->seq_type1 = scanner->approx_method1 == CV_CHAIN_CODE ?
- CV_SEQ_CHAIN_CONTOUR : CV_SEQ_POLYGON;
-
- scanner->seq_type2 = scanner->approx_method2 == CV_CHAIN_CODE ?
- CV_SEQ_CHAIN_CONTOUR : CV_SEQ_POLYGON;
-
- cvSaveMemStoragePos( storage, &(scanner->initial_pos) );
-
- if( method > CV_CHAIN_APPROX_SIMPLE )
- {
- scanner->storage1 = cvCreateChildMemStorage( scanner->storage2 );
- }
-
- if( mode > CV_RETR_LIST )
- {
- scanner->cinfo_storage = cvCreateChildMemStorage( scanner->storage2 );
- scanner->cinfo_set = cvCreateSet( 0, sizeof( CvSet ), sizeof( _CvContourInfo ),
- scanner->cinfo_storage );
- if( scanner->cinfo_storage == 0 || scanner->cinfo_set == 0 )
- CV_ERROR_FROM_STATUS( CV_OUTOFMEM_ERR );
- }
-
- /* make zero borders */
- memset( img, 0, size.width );
- memset( img + step * (size.height - 1), 0, size.width );
-
- for( y = 1, img += step; y < size.height - 1; y++, img += step )
- {
- img[0] = img[size.width - 1] = 0;
- }
-
- /* converts all pixels to 0 or 1 */
- cvThreshold( mat, mat, 0, 1, CV_THRESH_BINARY );
- CV_CHECK();
-
- __END__;
-
- if( cvGetErrStatus() < 0 )
- cvFree( &scanner );
-
- return scanner;
-}
-
-/*
- Final stage of contour processing.
- Three variants possible:
- 1. Contour, which was retrieved using border following, is added to
- the contour tree. It is the case when the icvSubstituteContour function
- was not called after retrieving the contour.
-
- 2. New contour, assigned by icvSubstituteContour function, is added to the
- tree. The retrieved contour itself is removed from the storage.
- Here two cases are possible:
- 2a. If one deals with plane variant of algorithm
- (hierarchical strucutre is not reconstructed),
- the contour is removed completely.
- 2b. In hierarchical case, the header of the contour is not removed.
- It's marked as "link to contour" and h_next pointer of it is set to
- new, substituting contour.
-
- 3. The similar to 2, but when NULL pointer was assigned by
- icvSubstituteContour function. In this case, the function removes
- retrieved contour completely if plane case and
- leaves header if hierarchical (but doesn't mark header as "link").
- ------------------------------------------------------------------------
- The 1st variant can be used to retrieve and store all the contours from the image
- (with optional convertion from chains to contours using some approximation from
- restriced set of methods). Some characteristics of contour can be computed in the
- same pass.
-
- The usage scheme can look like:
-
- icvContourScanner scanner;
- CvMemStorage* contour_storage;
- CvSeq* first_contour;
- CvStatus result;
-
- ...
-
- icvCreateMemStorage( &contour_storage, block_size/0 );
-
- ...
-
- cvStartFindContours
- ( img, contour_storage,
- header_size, approx_method,
- [external_only,]
- &scanner );
-
- for(;;)
- {
- [CvSeq* contour;]
- result = icvFindNextContour( &scanner, &contour/0 );
-
- if( result != CV_OK ) break;
-
- // calculate some characteristics
- ...
- }
-
- if( result < 0 ) goto error_processing;
-
- cvEndFindContours( &scanner, &first_contour );
- ...
-
- -----------------------------------------------------------------
-
- Second variant is more complex and can be used when someone wants store not
- the retrieved contours but transformed ones. (e.g. approximated with some
- non-default algorithm ).
-
- The scheme can be the as following:
-
- icvContourScanner scanner;
- CvMemStorage* contour_storage;
- CvMemStorage* temp_storage;
- CvSeq* first_contour;
- CvStatus result;
-
- ...
-
- icvCreateMemStorage( &contour_storage, block_size/0 );
- icvCreateMemStorage( &temp_storage, block_size/0 );
-
- ...
-
- icvStartFindContours8uC1R
- ( <img_params>, temp_storage,
- header_size, approx_method,
- [retrival_mode],
- &scanner );
-
- for(;;)
- {
- CvSeq* temp_contour;
- CvSeq* new_contour;
- result = icvFindNextContour( scanner, &temp_contour );
-
- if( result != CV_OK ) break;
-
- <approximation_function>( temp_contour, contour_storage,
- &new_contour, <parameters...> );
-
- icvSubstituteContour( scanner, new_contour );
- ...
- }
-
- if( result < 0 ) goto error_processing;
-
- cvEndFindContours( &scanner, &first_contour );
- ...
-
- ----------------------------------------------------------------------------
- Third method to retrieve contours may be applied if contours are irrelevant
- themselves but some characteristics of them are used only.
- The usage is similar to second except slightly different internal loop
-
- for(;;)
- {
- CvSeq* temp_contour;
- result = icvFindNextContour( &scanner, &temp_contour );
-
- if( result != CV_OK ) break;
-
- // calculate some characteristics of temp_contour
-
- icvSubstituteContour( scanner, 0 );
- ...
- }
-
- new_storage variable is not needed here.
-
- Two notes.
- 1. Second and third method can interleave. I.e. it is possible to
- remain contours that satisfy with some criteria and reject others.
- In hierarchic case the resulting tree is the part of original tree with
- some nodes absent. But in the resulting tree the contour1 is a child
- (may be indirect) of contour2 iff in the original tree the contour1
- is a child (may be indirect) of contour2.
-*/
-static void
-icvEndProcessContour( CvContourScanner scanner )
-{
- _CvContourInfo *l_cinfo = scanner->l_cinfo;
-
- if( l_cinfo )
- {
- if( scanner->subst_flag )
- {
- CvMemStoragePos temp;
-
- cvSaveMemStoragePos( scanner->storage2, &temp );
-
- if( temp.top == scanner->backup_pos2.top &&
- temp.free_space == scanner->backup_pos2.free_space )
- {
- cvRestoreMemStoragePos( scanner->storage2, &scanner->backup_pos );
- }
- scanner->subst_flag = 0;
- }
-
- if( l_cinfo->contour )
- {
- cvInsertNodeIntoTree( l_cinfo->contour, l_cinfo->parent->contour,
- &(scanner->frame) );
- }
- scanner->l_cinfo = 0;
- }
-}
-
-/* replaces one contour with another */
-CV_IMPL void
-cvSubstituteContour( CvContourScanner scanner, CvSeq * new_contour )
-{
- _CvContourInfo *l_cinfo;
-
- CV_FUNCNAME( "cvSubstituteContour" );
-
- __BEGIN__;
-
- if( !scanner )
- CV_ERROR( CV_StsNullPtr, "" );
-
- l_cinfo = scanner->l_cinfo;
- if( l_cinfo && l_cinfo->contour && l_cinfo->contour != new_contour )
- {
- l_cinfo->contour = new_contour;
- scanner->subst_flag = 1;
- }
-
- __END__;
-}
-
-
-/*
- marks domain border with +/-<constant> and stores the contour into CvSeq.
- method:
- <0 - chain
- ==0 - direct
- >0 - simple approximation
-*/
-static CvStatus
-icvFetchContour( schar *ptr,
- int step,
- CvPoint pt,
- CvSeq* contour,
- int _method )
-{
- const schar nbd = 2;
- int deltas[16];
- CvSeqWriter writer;
- schar *i0 = ptr, *i1, *i3, *i4 = 0;
- int prev_s = -1, s, s_end;
- int method = _method - 1;
-
- assert( (unsigned) _method <= CV_CHAIN_APPROX_SIMPLE );
-
- /* initialize local state */
- CV_INIT_3X3_DELTAS( deltas, step, 1 );
- memcpy( deltas + 8, deltas, 8 * sizeof( deltas[0] ));
-
- /* initialize writer */
- cvStartAppendToSeq( contour, &writer );
-
- if( method < 0 )
- ((CvChain *) contour)->origin = pt;
-
- s_end = s = CV_IS_SEQ_HOLE( contour ) ? 0 : 4;
-
- do
- {
- s = (s - 1) & 7;
- i1 = i0 + deltas[s];
- if( *i1 != 0 )
- break;
- }
- while( s != s_end );
-
- if( s == s_end ) /* single pixel domain */
- {
- *i0 = (schar) (nbd | -128);
- if( method >= 0 )
- {
- CV_WRITE_SEQ_ELEM( pt, writer );
- }
- }
- else
- {
- i3 = i0;
- prev_s = s ^ 4;
-
- /* follow border */
- for( ;; )
- {
- s_end = s;
-
- for( ;; )
- {
- i4 = i3 + deltas[++s];
- if( *i4 != 0 )
- break;
- }
- s &= 7;
-
- /* check "right" bound */
- if( (unsigned) (s - 1) < (unsigned) s_end )
- {
- *i3 = (schar) (nbd | -128);
- }
- else if( *i3 == 1 )
- {
- *i3 = nbd;
- }
-
- if( method < 0 )
- {
- schar _s = (schar) s;
-
- CV_WRITE_SEQ_ELEM( _s, writer );
- }
- else
- {
- if( s != prev_s || method == 0 )
- {
- CV_WRITE_SEQ_ELEM( pt, writer );
- prev_s = s;
- }
-
- pt.x += icvCodeDeltas[s].x;
- pt.y += icvCodeDeltas[s].y;
-
- }
-
- if( i4 == i0 && i3 == i1 )
- break;
-
- i3 = i4;
- s = (s + 4) & 7;
- } /* end of border following loop */
- }
-
- cvEndWriteSeq( &writer );
-
- if( _method != CV_CHAIN_CODE )
- cvBoundingRect( contour, 1 );
-
- assert( writer.seq->total == 0 && writer.seq->first == 0 ||
- writer.seq->total > writer.seq->first->count ||
- (writer.seq->first->prev == writer.seq->first &&
- writer.seq->first->next == writer.seq->first) );
-
- return CV_OK;
-}
-
-
-
-/*
- trace contour until certain point is met.
- returns 1 if met, 0 else.
-*/
-static int
-icvTraceContour( schar *ptr, int step, schar *stop_ptr, int is_hole )
-{
- int deltas[16];
- schar *i0 = ptr, *i1, *i3, *i4;
- int s, s_end;
-
- /* initialize local state */
- CV_INIT_3X3_DELTAS( deltas, step, 1 );
- memcpy( deltas + 8, deltas, 8 * sizeof( deltas[0] ));
-
- assert( (*i0 & -2) != 0 );
-
- s_end = s = is_hole ? 0 : 4;
-
- do
- {
- s = (s - 1) & 7;
- i1 = i0 + deltas[s];
- if( *i1 != 0 )
- break;
- }
- while( s != s_end );
-
- i3 = i0;
-
- /* check single pixel domain */
- if( s != s_end )
- {
- /* follow border */
- for( ;; )
- {
- s_end = s;
-
- for( ;; )
- {
- i4 = i3 + deltas[++s];
- if( *i4 != 0 )
- break;
- }
-
- if( i3 == stop_ptr || (i4 == i0 && i3 == i1) )
- break;
-
- i3 = i4;
- s = (s + 4) & 7;
- } /* end of border following loop */
- }
- return i3 == stop_ptr;
-}
-
-
-static CvStatus
-icvFetchContourEx( schar* ptr,
- int step,
- CvPoint pt,
- CvSeq* contour,
- int _method,
- int nbd,
- CvRect* _rect )
-{
- int deltas[16];
- CvSeqWriter writer;
- schar *i0 = ptr, *i1, *i3, *i4;
- CvRect rect;
- int prev_s = -1, s, s_end;
- int method = _method - 1;
-
- assert( (unsigned) _method <= CV_CHAIN_APPROX_SIMPLE );
- assert( 1 < nbd && nbd < 128 );
-
- /* initialize local state */
- CV_INIT_3X3_DELTAS( deltas, step, 1 );
- memcpy( deltas + 8, deltas, 8 * sizeof( deltas[0] ));
-
- /* initialize writer */
- cvStartAppendToSeq( contour, &writer );
-
- if( method < 0 )
- ((CvChain *)contour)->origin = pt;
-
- rect.x = rect.width = pt.x;
- rect.y = rect.height = pt.y;
-
- s_end = s = CV_IS_SEQ_HOLE( contour ) ? 0 : 4;
-
- do
- {
- s = (s - 1) & 7;
- i1 = i0 + deltas[s];
- if( *i1 != 0 )
- break;
- }
- while( s != s_end );
-
- if( s == s_end ) /* single pixel domain */
- {
- *i0 = (schar) (nbd | 0x80);
- if( method >= 0 )
- {
- CV_WRITE_SEQ_ELEM( pt, writer );
- }
- }
- else
- {
- i3 = i0;
-
- prev_s = s ^ 4;
-
- /* follow border */
- for( ;; )
- {
- s_end = s;
-
- for( ;; )
- {
- i4 = i3 + deltas[++s];
- if( *i4 != 0 )
- break;
- }
- s &= 7;
-
- /* check "right" bound */
- if( (unsigned) (s - 1) < (unsigned) s_end )
- {
- *i3 = (schar) (nbd | 0x80);
- }
- else if( *i3 == 1 )
- {
- *i3 = (schar) nbd;
- }
-
- if( method < 0 )
- {
- schar _s = (schar) s;
- CV_WRITE_SEQ_ELEM( _s, writer );
- }
- else if( s != prev_s || method == 0 )
- {
- CV_WRITE_SEQ_ELEM( pt, writer );
- }
-
- if( s != prev_s )
- {
- /* update bounds */
- if( pt.x < rect.x )
- rect.x = pt.x;
- else if( pt.x > rect.width )
- rect.width = pt.x;
-
- if( pt.y < rect.y )
- rect.y = pt.y;
- else if( pt.y > rect.height )
- rect.height = pt.y;
- }
-
- prev_s = s;
- pt.x += icvCodeDeltas[s].x;
- pt.y += icvCodeDeltas[s].y;
-
- if( i4 == i0 && i3 == i1 ) break;
-
- i3 = i4;
- s = (s + 4) & 7;
- } /* end of border following loop */
- }
-
- rect.width -= rect.x - 1;
- rect.height -= rect.y - 1;
-
- cvEndWriteSeq( &writer );
-
- if( _method != CV_CHAIN_CODE )
- ((CvContour*)contour)->rect = rect;
-
- assert( writer.seq->total == 0 && writer.seq->first == 0 ||
- writer.seq->total > writer.seq->first->count ||
- (writer.seq->first->prev == writer.seq->first &&
- writer.seq->first->next == writer.seq->first) );
-
- if( _rect ) *_rect = rect;
-
- return CV_OK;
-}
-
-
-CvSeq *
-cvFindNextContour( CvContourScanner scanner )
-{
- schar *img0;
- schar *img;
- int step;
- int width, height;
- int x, y;
- int prev;
- CvPoint lnbd;
- CvSeq *contour = 0;
- int nbd;
- int mode;
- CvStatus result = (CvStatus) 1;
-
- CV_FUNCNAME( "cvFindNextContour" );
-
- __BEGIN__;
-
- if( !scanner )
- CV_ERROR( CV_StsNullPtr, "" );
- icvEndProcessContour( scanner );
-
- /* initialize local state */
- img0 = scanner->img0;
- img = scanner->img;
- step = scanner->img_step;
- x = scanner->pt.x;
- y = scanner->pt.y;
- width = scanner->img_size.width;
- height = scanner->img_size.height;
- mode = scanner->mode;
- lnbd = scanner->lnbd;
- nbd = scanner->nbd;
-
- prev = img[x - 1];
-
- for( ; y < height; y++, img += step )
- {
- for( ; x < width; x++ )
- {
- int p = img[x];
-
- if( p != prev )
- {
- _CvContourInfo *par_info = 0;
- _CvContourInfo *l_cinfo = 0;
- CvSeq *seq = 0;
- int is_hole = 0;
- CvPoint origin;
-
- if( !(prev == 0 && p == 1) ) /* if not external contour */
- {
- /* check hole */
- if( p != 0 || prev < 1 )
- goto resume_scan;
-
- if( prev & -2 )
- {
- lnbd.x = x - 1;
- }
- is_hole = 1;
- }
-
- if( mode == 0 && (is_hole || img0[lnbd.y * step + lnbd.x] > 0) )
- goto resume_scan;
-
- origin.y = y;
- origin.x = x - is_hole;
-
- /* find contour parent */
- if( mode <= 1 || (!is_hole && mode == 2) || lnbd.x <= 0 )
- {
- par_info = &(scanner->frame_info);
- }
- else
- {
- int lval = img0[lnbd.y * step + lnbd.x] & 0x7f;
- _CvContourInfo *cur = scanner->cinfo_table[lval - 2];
-
- assert( lval >= 2 );
-
- /* find the first bounding contour */
- while( cur )
- {
- if( (unsigned) (lnbd.x - cur->rect.x) < (unsigned) cur->rect.width &&
- (unsigned) (lnbd.y - cur->rect.y) < (unsigned) cur->rect.height )
- {
- if( par_info )
- {
- if( icvTraceContour( scanner->img0 +
- par_info->origin.y * step +
- par_info->origin.x, step, img + lnbd.x,
- par_info->is_hole ) > 0 )
- break;
- }
- par_info = cur;
- }
- cur = cur->next;
- }
-
- assert( par_info != 0 );
-
- /* if current contour is a hole and previous contour is a hole or
- current contour is external and previous contour is external then
- the parent of the contour is the parent of the previous contour else
- the parent is the previous contour itself. */
- if( par_info->is_hole == is_hole )
- {
- par_info = par_info->parent;
- /* every contour must have a parent
- (at least, the frame of the image) */
- if( !par_info )
- par_info = &(scanner->frame_info);
- }
-
- /* hole flag of the parent must differ from the flag of the contour */
- assert( par_info->is_hole != is_hole );
- if( par_info->contour == 0 ) /* removed contour */
- goto resume_scan;
- }
-
- lnbd.x = x - is_hole;
-
- cvSaveMemStoragePos( scanner->storage2, &(scanner->backup_pos) );
-
- seq = cvCreateSeq( scanner->seq_type1, scanner->header_size1,
- scanner->elem_size1, scanner->storage1 );
- if( !seq )
- {
- result = CV_OUTOFMEM_ERR;
- goto exit_func;
- }
- seq->flags |= is_hole ? CV_SEQ_FLAG_HOLE : 0;
-
- /* initialize header */
- if( mode <= 1 )
- {
- l_cinfo = &(scanner->cinfo_temp);
- result = icvFetchContour( img + x - is_hole, step,
- cvPoint( origin.x + scanner->offset.x,
- origin.y + scanner->offset.y),
- seq, scanner->approx_method1 );
- if( result < 0 )
- goto exit_func;
- }
- else
- {
- union { _CvContourInfo* ci; CvSetElem* se; } v;
- v.ci = l_cinfo;
- cvSetAdd( scanner->cinfo_set, 0, &v.se );
- l_cinfo = v.ci;
-
- result = icvFetchContourEx( img + x - is_hole, step,
- cvPoint( origin.x + scanner->offset.x,
- origin.y + scanner->offset.y),
- seq, scanner->approx_method1,
- nbd, &(l_cinfo->rect) );
- if( result < 0 )
- goto exit_func;
- l_cinfo->rect.x -= scanner->offset.x;
- l_cinfo->rect.y -= scanner->offset.y;
-
- l_cinfo->next = scanner->cinfo_table[nbd - 2];
- scanner->cinfo_table[nbd - 2] = l_cinfo;
-
- /* change nbd */
- nbd = (nbd + 1) & 127;
- nbd += nbd == 0 ? 3 : 0;
- }
-
- l_cinfo->is_hole = is_hole;
- l_cinfo->contour = seq;
- l_cinfo->origin = origin;
- l_cinfo->parent = par_info;
-
- if( scanner->approx_method1 != scanner->approx_method2 )
- {
- result = icvApproximateChainTC89( (CvChain *) seq,
- scanner->header_size2,
- scanner->storage2,
- &(l_cinfo->contour),
- scanner->approx_method2 );
- if( result < 0 )
- goto exit_func;
- cvClearMemStorage( scanner->storage1 );
- }
-
- l_cinfo->contour->v_prev = l_cinfo->parent->contour;
-
- if( par_info->contour == 0 )
- {
- l_cinfo->contour = 0;
- if( scanner->storage1 == scanner->storage2 )
- {
- cvRestoreMemStoragePos( scanner->storage1, &(scanner->backup_pos) );
- }
- else
- {
- cvClearMemStorage( scanner->storage1 );
- }
- p = img[x];
- goto resume_scan;
- }
-
- cvSaveMemStoragePos( scanner->storage2, &(scanner->backup_pos2) );
- scanner->l_cinfo = l_cinfo;
- scanner->pt.x = x + 1;
- scanner->pt.y = y;
- scanner->lnbd = lnbd;
- scanner->img = (schar *) img;
- scanner->nbd = nbd;
- contour = l_cinfo->contour;
-
- result = CV_OK;
- goto exit_func;
- resume_scan:
- prev = p;
- /* update lnbd */
- if( prev & -2 )
- {
- lnbd.x = x;
- }
- } /* end of prev != p */
- } /* end of loop on x */
-
- lnbd.x = 0;
- lnbd.y = y + 1;
- x = 1;
- prev = 0;
-
- } /* end of loop on y */
-
- exit_func:
-
- if( result != 0 )
- contour = 0;
- if( result < 0 )
- CV_ERROR_FROM_STATUS( result );
-
- __END__;
-
- return contour;
-}
-
-
-/*
- The function add to tree the last retrieved/substituted contour,
- releases temp_storage, restores state of dst_storage (if needed), and
- returns pointer to root of the contour tree */
-CV_IMPL CvSeq *
-cvEndFindContours( CvContourScanner * _scanner )
-{
- CvContourScanner scanner;
- CvSeq *first = 0;
-
- CV_FUNCNAME( "cvFindNextContour" );
-
- __BEGIN__;
-
- if( !_scanner )
- CV_ERROR( CV_StsNullPtr, "" );
- scanner = *_scanner;
-
- if( scanner )
- {
- icvEndProcessContour( scanner );
-
- if( scanner->storage1 != scanner->storage2 )
- cvReleaseMemStorage( &(scanner->storage1) );
-
- if( scanner->cinfo_storage )
- cvReleaseMemStorage( &(scanner->cinfo_storage) );
-
- first = scanner->frame.v_next;
- cvFree( _scanner );
- }
-
- __END__;
-
- return first;
-}
-
-
-#define ICV_SINGLE 0
-#define ICV_CONNECTING_ABOVE 1
-#define ICV_CONNECTING_BELOW -1
-#define ICV_IS_COMPONENT_POINT(val) ((val) != 0)
-
-#define CV_GET_WRITTEN_ELEM( writer ) ((writer).ptr - (writer).seq->elem_size)
-
-typedef struct CvLinkedRunPoint
-{
- struct CvLinkedRunPoint* link;
- struct CvLinkedRunPoint* next;
- CvPoint pt;
-}
-CvLinkedRunPoint;
-
-
-static int
-icvFindContoursInInterval( const CvArr* src,
- /*int minValue, int maxValue,*/
- CvMemStorage* storage,
- CvSeq** result,
- int contourHeaderSize )
-{
- int count = 0;
- CvMemStorage* storage00 = 0;
- CvMemStorage* storage01 = 0;
- CvSeq* first = 0;
-
- CV_FUNCNAME( "icvFindContoursInInterval" );
-
- __BEGIN__;
-
- int i, j, k, n;
-
- uchar* src_data = 0;
- int img_step = 0;
- CvSize img_size;
-
- int connect_flag;
- int lower_total;
- int upper_total;
- int all_total;
-
- CvSeq* runs;
- CvLinkedRunPoint tmp;
- CvLinkedRunPoint* tmp_prev;
- CvLinkedRunPoint* upper_line = 0;
- CvLinkedRunPoint* lower_line = 0;
- CvLinkedRunPoint* last_elem;
-
- CvLinkedRunPoint* upper_run = 0;
- CvLinkedRunPoint* lower_run = 0;
- CvLinkedRunPoint* prev_point = 0;
-
- CvSeqWriter writer_ext;
- CvSeqWriter writer_int;
- CvSeqWriter writer;
- CvSeqReader reader;
-
- CvSeq* external_contours;
- CvSeq* internal_contours;
- CvSeq* prev = 0;
-
- if( !storage )
- CV_ERROR( CV_StsNullPtr, "NULL storage pointer" );
-
- if( !result )
- CV_ERROR( CV_StsNullPtr, "NULL double CvSeq pointer" );
-
- if( contourHeaderSize < (int)sizeof(CvContour))
- CV_ERROR( CV_StsBadSize, "Contour header size must be >= sizeof(CvContour)" );
-
- CV_CALL( storage00 = cvCreateChildMemStorage(storage));
- CV_CALL( storage01 = cvCreateChildMemStorage(storage));
-
- {
- CvMat stub, *mat;
-
- CV_CALL( mat = cvGetMat( src, &stub ));
- if( !CV_IS_MASK_ARR(mat))
- CV_ERROR( CV_StsBadArg, "Input array must be 8uC1 or 8sC1" );
- src_data = mat->data.ptr;
- img_step = mat->step;
- img_size = cvGetMatSize( mat );
- }
-
- // Create temporary sequences
- runs = cvCreateSeq(0, sizeof(CvSeq), sizeof(CvLinkedRunPoint), storage00 );
- cvStartAppendToSeq( runs, &writer );
-
- cvStartWriteSeq( 0, sizeof(CvSeq), sizeof(CvLinkedRunPoint*), storage01, &writer_ext );
- cvStartWriteSeq( 0, sizeof(CvSeq), sizeof(CvLinkedRunPoint*), storage01, &writer_int );
-
- tmp_prev = &(tmp);
- tmp_prev->next = 0;
- tmp_prev->link = 0;
-
- // First line. None of runs is binded
- tmp.pt.y = 0;
- i = 0;
- CV_WRITE_SEQ_ELEM( tmp, writer );
- upper_line = (CvLinkedRunPoint*)CV_GET_WRITTEN_ELEM( writer );
-
- tmp_prev = upper_line;
- for( j = 0; j < img_size.width; )
- {
- for( ; j < img_size.width && !ICV_IS_COMPONENT_POINT(src_data[j]); j++ )
- ;
- if( j == img_size.width )
- break;
-
- tmp.pt.x = j;
- CV_WRITE_SEQ_ELEM( tmp, writer );
- tmp_prev->next = (CvLinkedRunPoint*)CV_GET_WRITTEN_ELEM( writer );
- tmp_prev = tmp_prev->next;
-
- for( ; j < img_size.width && ICV_IS_COMPONENT_POINT(src_data[j]); j++ )
- ;
-
- tmp.pt.x = j-1;
- CV_WRITE_SEQ_ELEM( tmp, writer );
- tmp_prev->next = (CvLinkedRunPoint*)CV_GET_WRITTEN_ELEM( writer );
- tmp_prev->link = tmp_prev->next;
- // First point of contour
- CV_WRITE_SEQ_ELEM( tmp_prev, writer_ext );
- tmp_prev = tmp_prev->next;
- }
- cvFlushSeqWriter( &writer );
- upper_line = upper_line->next;
- upper_total = runs->total - 1;
- last_elem = tmp_prev;
- tmp_prev->next = 0;
-
- for( i = 1; i < img_size.height; i++ )
- {
-//------// Find runs in next line
- src_data += img_step;
- tmp.pt.y = i;
- all_total = runs->total;
- for( j = 0; j < img_size.width; )
- {
- for( ; j < img_size.width && !ICV_IS_COMPONENT_POINT(src_data[j]); j++ )
- ;
- if( j == img_size.width ) break;
-
- tmp.pt.x = j;
- CV_WRITE_SEQ_ELEM( tmp, writer );
- tmp_prev->next = (CvLinkedRunPoint*)CV_GET_WRITTEN_ELEM( writer );
- tmp_prev = tmp_prev->next;
-
- for( ; j < img_size.width && ICV_IS_COMPONENT_POINT(src_data[j]); j++ )
- ;
-
- tmp.pt.x = j-1;
- CV_WRITE_SEQ_ELEM( tmp, writer );
- tmp_prev = tmp_prev->next = (CvLinkedRunPoint*)CV_GET_WRITTEN_ELEM( writer );
- }//j
- cvFlushSeqWriter( &writer );
- lower_line = last_elem->next;
- lower_total = runs->total - all_total;
- last_elem = tmp_prev;
- tmp_prev->next = 0;
-//------//
-//------// Find links between runs of lower_line and upper_line
- upper_run = upper_line;
- lower_run = lower_line;
- connect_flag = ICV_SINGLE;
-
- for( k = 0, n = 0; k < upper_total/2 && n < lower_total/2; )
- {
- switch( connect_flag )
- {
- case ICV_SINGLE:
- if( upper_run->next->pt.x < lower_run->next->pt.x )
- {
- if( upper_run->next->pt.x >= lower_run->pt.x -1 )
- {
- lower_run->link = upper_run;
- connect_flag = ICV_CONNECTING_ABOVE;
- prev_point = upper_run->next;
- }
- else
- upper_run->next->link = upper_run;
- k++;
- upper_run = upper_run->next->next;
- }
- else
- {
- if( upper_run->pt.x <= lower_run->next->pt.x +1 )
- {
- lower_run->link = upper_run;
- connect_flag = ICV_CONNECTING_BELOW;
- prev_point = lower_run->next;
- }
- else
- {
- lower_run->link = lower_run->next;
- // First point of contour
- CV_WRITE_SEQ_ELEM( lower_run, writer_ext );
- }
- n++;
- lower_run = lower_run->next->next;
- }
- break;
- case ICV_CONNECTING_ABOVE:
- if( upper_run->pt.x > lower_run->next->pt.x +1 )
- {
- prev_point->link = lower_run->next;
- connect_flag = ICV_SINGLE;
- n++;
- lower_run = lower_run->next->next;
- }
- else
- {
- prev_point->link = upper_run;
- if( upper_run->next->pt.x < lower_run->next->pt.x )
- {
- k++;
- prev_point = upper_run->next;
- upper_run = upper_run->next->next;
- }
- else
- {
- connect_flag = ICV_CONNECTING_BELOW;
- prev_point = lower_run->next;
- n++;
- lower_run = lower_run->next->next;
- }
- }
- break;
- case ICV_CONNECTING_BELOW:
- if( lower_run->pt.x > upper_run->next->pt.x +1 )
- {
- upper_run->next->link = prev_point;
- connect_flag = ICV_SINGLE;
- k++;
- upper_run = upper_run->next->next;
- }
- else
- {
- // First point of contour
- CV_WRITE_SEQ_ELEM( lower_run, writer_int );
-
- lower_run->link = prev_point;
- if( lower_run->next->pt.x < upper_run->next->pt.x )
- {
- n++;
- prev_point = lower_run->next;
- lower_run = lower_run->next->next;
- }
- else
- {
- connect_flag = ICV_CONNECTING_ABOVE;
- k++;
- prev_point = upper_run->next;
- upper_run = upper_run->next->next;
- }
- }
- break;
- }
- }// k, n
-
- for( ; n < lower_total/2; n++ )
- {
- if( connect_flag != ICV_SINGLE )
- {
- prev_point->link = lower_run->next;
- connect_flag = ICV_SINGLE;
- lower_run = lower_run->next->next;
- continue;
- }
- lower_run->link = lower_run->next;
-
- //First point of contour
- CV_WRITE_SEQ_ELEM( lower_run, writer_ext );
-
- lower_run = lower_run->next->next;
- }
-
- for( ; k < upper_total/2; k++ )
- {
- if( connect_flag != ICV_SINGLE )
- {
- upper_run->next->link = prev_point;
- connect_flag = ICV_SINGLE;
- upper_run = upper_run->next->next;
- continue;
- }
- upper_run->next->link = upper_run;
- upper_run = upper_run->next->next;
- }
- upper_line = lower_line;
- upper_total = lower_total;
- }//i
-
- upper_run = upper_line;
-
- //the last line of image
- for( k = 0; k < upper_total/2; k++ )
- {
- upper_run->next->link = upper_run;
- upper_run = upper_run->next->next;
- }
-
-//------//
-//------//Find end read contours
- external_contours = cvEndWriteSeq( &writer_ext );
- internal_contours = cvEndWriteSeq( &writer_int );
-
- for( k = 0; k < 2; k++ )
- {
- CvSeq* contours = k == 0 ? external_contours : internal_contours;
-
- cvStartReadSeq( contours, &reader );
-
- for( j = 0; j < contours->total; j++, count++ )
- {
- CvLinkedRunPoint* p_temp;
- CvLinkedRunPoint* p00;
- CvLinkedRunPoint* p01;
- CvSeq* contour;
-
- CV_READ_SEQ_ELEM( p00, reader );
- p01 = p00;
-
- if( !p00->link )
- continue;
-
- cvStartWriteSeq( CV_SEQ_ELTYPE_POINT | CV_SEQ_POLYLINE | CV_SEQ_FLAG_CLOSED,
- contourHeaderSize, sizeof(CvPoint), storage, &writer );
- do
- {
- CV_WRITE_SEQ_ELEM( p00->pt, writer );
- p_temp = p00;
- p00 = p00->link;
- p_temp->link = 0;
- }
- while( p00 != p01 );
-
- contour = cvEndWriteSeq( &writer );
- cvBoundingRect( contour, 1 );
-
- if( k != 0 )
- contour->flags |= CV_SEQ_FLAG_HOLE;
-
- if( !first )
- prev = first = contour;
- else
- {
- contour->h_prev = prev;
- prev = prev->h_next = contour;
- }
- }
- }
-
- __END__;
-
- if( !first )
- count = -1;
-
- if( result )
- *result = first;
-
- cvReleaseMemStorage(&storage00);
- cvReleaseMemStorage(&storage01);
-
- return count;
-}
-
-
-
-/*F///////////////////////////////////////////////////////////////////////////////////////
-// Name: cvFindContours
-// Purpose:
-// Finds all the contours on the bi-level image.
-// Context:
-// Parameters:
-// img - source image.
-// Non-zero pixels are considered as 1-pixels
-// and zero pixels as 0-pixels.
-// step - full width of source image in bytes.
-// size - width and height of the image in pixels
-// storage - pointer to storage where will the output contours be placed.
-// header_size - header size of resulting contours
-// mode - mode of contour retrieval.
-// method - method of approximation that is applied to contours
-// first_contour - pointer to first contour pointer
-// Returns:
-// CV_OK or error code
-// Notes:
-//F*/
-CV_IMPL int
-cvFindContours( void* img, CvMemStorage* storage,
- CvSeq** firstContour, int cntHeaderSize,
- int mode,
- int method, CvPoint offset )
-{
- CvContourScanner scanner = 0;
- CvSeq *contour = 0;
- int count = -1;
-
- CV_FUNCNAME( "cvFindContours" );
-
- __BEGIN__;
-
- if( !firstContour )
- CV_ERROR( CV_StsNullPtr, "NULL double CvSeq pointer" );
-
- if( method == CV_LINK_RUNS )
- {
- if( offset.x != 0 || offset.y != 0 )
- CV_ERROR( CV_StsOutOfRange,
- "Nonzero offset is not supported in CV_LINK_RUNS yet" );
-
- CV_CALL( count = icvFindContoursInInterval( img, storage,
- firstContour, cntHeaderSize ));
- }
- else
- {
- CV_CALL( scanner = cvStartFindContours( img, storage,
- cntHeaderSize, mode, method, offset ));
- assert( scanner );
-
- do
- {
- count++;
- contour = cvFindNextContour( scanner );
- }
- while( contour != 0 );
-
- *firstContour = cvEndFindContours( &scanner );
- }
-
- __END__;
-
- return count;
-}
-
-
-/* End of file. */