//
// ch9_watershed image
// This is an exact copy of the watershed.cpp demo in the OpenCV ../samples/c directory
//
// Think about using a morphologically eroded forground and background segmented image as the template
// for the watershed algorithm to segment objects by color and edges for collecting 
//
/* *************** License:**************************
 Oct. 3, 2008
 Right to use this code in any way you want without warrenty, support or any guarentee of it working.

 BOOK: It would be nice if you cited it:
 Learning OpenCV: Computer Vision with the OpenCV Library
 by Gary Bradski and Adrian Kaehler
 Published by O'Reilly Media, October 3, 2008

 AVAILABLE AT: 
 http://www.amazon.com/Learning-OpenCV-Computer-Vision-Library/dp/0596516134
 Or: http://oreilly.com/catalog/9780596516130/
 ISBN-10: 0596516134 or: ISBN-13: 978-0596516130 

 OTHER OPENCV SITES:
 * The source code is on sourceforge at:
 http://sourceforge.net/projects/opencvlibrary/
 * The OpenCV wiki page (As of Oct 1, 2008 this is down for changing over servers, but should come back):
 http://opencvlibrary.sourceforge.net/
 * An active user group is at:
 http://tech.groups.yahoo.com/group/OpenCV/
 * The minutes of weekly OpenCV development meetings are at:
 http://pr.willowgarage.com/wiki/OpenCV
 ************************************************** */

#include "cv.h"
#include "highgui.h"
#include <stdio.h>
#include <stdlib.h>

IplImage* marker_mask = 0;
IplImage* markers = 0;
IplImage* img0 = 0, *img = 0, *img_gray = 0, *wshed = 0;
CvPoint prev_pt = {-1,-1};

void on_mouse( int event, int x, int y, int flags, void* param )
{
 if( !img )
 return;

 if( event == CV_EVENT_LBUTTONUP || !(flags & CV_EVENT_FLAG_LBUTTON) )
 prev_pt = cvPoint(-1,-1);
 else if( event == CV_EVENT_LBUTTONDOWN )
 prev_pt = cvPoint(x,y);
 else if( event == CV_EVENT_MOUSEMOVE && (flags & CV_EVENT_FLAG_LBUTTON) )
 {
 CvPoint pt = cvPoint(x,y);
 if( prev_pt.x < 0 )
 prev_pt = pt;
 cvLine( marker_mask, prev_pt, pt, cvScalarAll(255), 5, 8, 0 );
 cvLine( img, prev_pt, pt, cvScalarAll(255), 5, 8, 0 );
 prev_pt = pt;
 cvShowImage( "image", img );
 }
}


int main( int argc, char** argv )
{
 char* filename = argc >= 2 ? argv[1] : (char*)"fruits.jpg";
 CvRNG rng = cvRNG(-1);

 if( (img0 = cvLoadImage(filename,1)) == 0 )
 return 0;

 printf( "Hot keys: \n"
 "\tESC - quit the program\n"
 "\tr - restore the original image\n"
 "\tw or ENTER - run watershed algorithm\n"
 "\t\t(before running it, roughly mark the areas on the image)\n"
 "\t (before that, roughly outline several markers on the image)\n" );
 
 cvNamedWindow( "image", 1 );
 cvNamedWindow( "watershed transform", 1 );

 img = cvCloneImage( img0 );
 img_gray = cvCloneImage( img0 );
 wshed = cvCloneImage( img0 );
 marker_mask = cvCreateImage( cvGetSize(img), 8, 1 );
 markers = cvCreateImage( cvGetSize(img), IPL_DEPTH_32S, 1 );
 cvCvtColor( img, marker_mask, CV_BGR2GRAY );
 cvCvtColor( marker_mask, img_gray, CV_GRAY2BGR );

 cvZero( marker_mask );
 cvZero( wshed );
 cvShowImage( "image", img );
 cvShowImage( "watershed transform", wshed );
 cvSetMouseCallback( "image", on_mouse, 0 );

 for(;;)
 {
 int c = cvWaitKey(0);

 if( (char)c == 27 )
 break;

 if( (char)c == 'r' )
 {
 cvZero( marker_mask );
 cvCopy( img0, img );
 cvShowImage( "image", img );
 }

 if( (char)c == 'w' || (char)c == '\n' )
 {
 CvMemStorage* storage = cvCreateMemStorage(0);
 CvSeq* contours = 0;
 CvMat* color_tab;
 int i, j, comp_count = 0;
 //cvSaveImage( "wshed_mask.png", marker_mask );
 //marker_mask = cvLoadImage( "wshed_mask.png", 0 );
 cvFindContours( marker_mask, storage, &contours, sizeof(CvContour),
 CV_RETR_CCOMP, CV_CHAIN_APPROX_SIMPLE );
 cvZero( markers );
 for( ; contours != 0; contours = contours->h_next, comp_count++ )
 {
 cvDrawContours( markers, contours, cvScalarAll(comp_count+1),
 cvScalarAll(comp_count+1), -1, -1, 8, cvPoint(0,0) );
 }

 color_tab = cvCreateMat( 1, comp_count, CV_8UC3 );
 for( i = 0; i < comp_count; i++ )
 {
 uchar* ptr = color_tab->data.ptr + i*3;
 ptr[0] = (uchar)(cvRandInt(&rng)%180 + 50);
 ptr[1] = (uchar)(cvRandInt(&rng)%180 + 50);
 ptr[2] = (uchar)(cvRandInt(&rng)%180 + 50);
 }

 {
 double t = (double)cvGetTickCount();
 cvWatershed( img0, markers );
 t = (double)cvGetTickCount() - t;
 printf( "exec time = %gms\n", t/(cvGetTickFrequency()*1000.) );
 }

 // paint the watershed image
 for( i = 0; i < markers->height; i++ )
 for( j = 0; j < markers->width; j++ )
 {
 int idx = CV_IMAGE_ELEM( markers, int, i, j );
 uchar* dst = &CV_IMAGE_ELEM( wshed, uchar, i, j*3 );
 if( idx == -1 )
 dst[0] = dst[1] = dst[2] = (uchar)255;
 else if( idx <= 0 || idx > comp_count )
 dst[0] = dst[1] = dst[2] = (uchar)0; // should not get here
 else
 {
 uchar* ptr = color_tab->data.ptr + (idx-1)*3;
 dst[0] = ptr[0]; dst[1] = ptr[1]; dst[2] = ptr[2];
 }
 }

 cvAddWeighted( wshed, 0.5, img_gray, 0.5, 0, wshed );
 cvShowImage( "watershed transform", wshed );
 cvReleaseMemStorage( &storage );
 cvReleaseMat( &color_tab );
 }
 }

 return 1;
}