void myCompLabelerGroup::doLabeling(Blob_vector &blobs)
{
t_labelType label = 0;
labelers[0]->Label();
for(int i=0; i<numThreads; i++) {
//cout << "MT pass " <<i<<"\t" << labelers[i]->blobs.size()<<endl;
for(unsigned int j=0; j<labelers[i]->blobs.size(); j++) {
labelers[i]->blobs[j]->SetID(label);
label++;
blobs.push_back(labelers[i]->blobs[j]);
}
}
}
/**
- FUNCIÓ: ComponentLabeling
- FUNCIONALITAT: Calcula els components binaris (blobs) d'una imatge amb connectivitat a 8
- PARÀMETRES:
- inputImage: image to segment (pixel values different than blobColor are treated as background)
- maskImage: if not NULL, all the pixels equal to 0 in mask are skipped in input image
- backgroundColor: color of background (ignored pixels)
- blobs: blob vector destination
- RESULTAT:
-
- RESTRICCIONS:
-
- AUTOR: rborras
- DATA DE CREACIÓ: 2008/04/21
- MODIFICACIÓ: Data. Autor. Descripció.
- NOTA: Algorithm based on "A linear-time component labeling algorithm using contour tracing technique",
F.Chang et al
*/
bool ComponentLabeling( IplImage* inputImage,
IplImage* maskImage,
unsigned char backgroundColor,
Blob_vector &blobs )
{
int i,j;
// row major vector with visited points
bool *visitedPoints, *pVisitedPoints, internalContour, externalContour;
unsigned char *pInputImage, *pMask, *pAboveInputImage, *pBelowInputImage,
*pAboveMask, *pBelowMask;
int imageWidth, imageHeight, currentLabel, contourLabel;
// row major vector with labelled image
t_labelType *labelledImage, *pLabels;
//! current blob pointer
CBlob *currentBlob;
CvSize imageSizes;
CvPoint currentPoint;
// verify input image
if( !CV_IS_IMAGE( inputImage ) )
return false;
// verify that input image and mask image has same size
if( maskImage )
{
if( !CV_IS_IMAGE(maskImage) ||
maskImage->width != inputImage->width ||
maskImage->height != inputImage->height )
return false;
}
else
{
pMask = NULL;
pAboveMask = NULL;
pBelowMask = NULL;
}
imageSizes = cvSize(inputImage->width,inputImage->height);
imageWidth = inputImage->width;
imageHeight = inputImage->height;
// create auxiliary buffers
labelledImage = (t_labelType*) malloc( inputImage->width * inputImage->height * sizeof(t_labelType) );
visitedPoints = (bool*) malloc( inputImage->width * inputImage->height * sizeof(bool) );
// initialize it to 0
memset(labelledImage, 0, inputImage->width * inputImage->height * sizeof(t_labelType) ) ;
memset(visitedPoints, false, inputImage->width * inputImage->height * sizeof(bool) ) ;
// initialize pointers and label counter
pLabels = labelledImage;
pVisitedPoints = visitedPoints;
currentLabel = 1;
for (j = 0; j < imageHeight; j++ )
{
// don't verify if we area on first or last row, it will verified on pointer access
pAboveInputImage = (unsigned char*) inputImage->imageData + (j-1) * inputImage->widthStep;
pBelowInputImage = (unsigned char*) inputImage->imageData + (j+1) * inputImage->widthStep;
pInputImage = (unsigned char*) inputImage->imageData + j * inputImage->widthStep;
if( maskImage )
{
pMask = (unsigned char*) maskImage->imageData + j * maskImage->widthStep;
// don't verify if we area on first or last row, it will verified on pointer access
pAboveMask = (unsigned char*) maskImage->imageData + (j-1) * maskImage->widthStep;
pBelowMask = (unsigned char*) maskImage->imageData + (j+1) * maskImage->widthStep;
}
for (i = 0; i < imageWidth; i++, pInputImage++, pMask++, pAboveInputImage++, pBelowInputImage++,
pAboveMask++, pBelowMask++ )
{
// ignore background pixels or 0 pixels in mask
if ( (*pInputImage == backgroundColor) || (maskImage && *pMask == 0 ))
{
pLabels++;
pVisitedPoints++;
continue;
}
// new external contour: current label == 0 and above pixel is background
if( j > 0 )
{
externalContour = ((*pAboveInputImage == backgroundColor) ||
(maskImage && *pAboveMask == 0)) &&
(*pLabels == 0);
}
else
externalContour = (*pLabels == 0);
// new internal contour: below pixel is background and not visited
if( !externalContour && j < imageHeight - 1 )
{
internalContour = *pBelowInputImage == backgroundColor &&
!GET_BELOW_VISITEDPIXEL( pVisitedPoints, imageWidth);
}
else
{
internalContour = false;
}
if( externalContour )
{
currentPoint = cvPoint(i,j);
// assign label to labelled image
*pLabels = currentLabel;
// create new blob
currentBlob = new CBlob(currentLabel, currentPoint, imageSizes );
// contour tracing with currentLabel
contourTracing( inputImage, maskImage, currentPoint,
labelledImage, visitedPoints,
currentLabel, false, backgroundColor, currentBlob->GetExternalContour() );
// add new created blob
blobs.push_back(currentBlob);
currentLabel++;
}
else
{
if( internalContour )
{
currentPoint = cvPoint(i,j);
if( *pLabels == 0 )
{
// take left neightbour value as current
if( i > 0 )
contourLabel = *(pLabels - 1);
}
else
{
contourLabel = *pLabels;
}
if(contourLabel>0)
{
currentBlob = blobs[contourLabel-1];
CBlobContour newContour(currentPoint, currentBlob->GetStorage());
// contour tracing with contourLabel
contourTracing( inputImage, maskImage, currentPoint, labelledImage, visitedPoints,
contourLabel, true, backgroundColor, &newContour );
currentBlob->AddInternalContour( newContour );
}
}
// neither internal nor external contour
else
{
// take left neightbour value as current if it is not labelled
if( i > 0 && *pLabels == 0 )
*pLabels = *(pLabels - 1);
}
}
pLabels++;
pVisitedPoints++;
}
}
// free auxiliary buffers
free( labelledImage );
free( visitedPoints );
return true;
}
