OpenCV Fingertip detection - opencv

Good day. I'm new to OpenCV and right now, I'm trying to do fingertip detection using colour tracking and background subtraction methods. I got the colour tracking part working but I have no idea on how to subtract the background and leave only the fingertips.
Here is my code.
#include <opencv2/opencv.hpp>
#include <stdio.h>
#include <iostream>
using namespace std;
IplImage* GetThresholdedImage(IplImage* img, CvScalar& lowerBound, CvScalar& upperBound)
{
// Convert the image into an HSV image
IplImage* imgHSV = cvCreateImage(cvGetSize(img), 8, 3);
cvCvtColor(img, imgHSV, CV_BGR2HSV);
IplImage* imgThreshed = cvCreateImage(cvGetSize(img), 8, 1);
cvInRangeS(imgHSV, lowerBound, upperBound, imgThreshed);
cvReleaseImage(&imgHSV);
return imgThreshed;
}
int main()
{
int lineThickness = 2;
CvScalar lowerBound = cvScalar(20, 100, 100);
CvScalar upperBound = cvScalar(30, 255, 255);
int b,g,r;
lowerBound = cvScalar(0,58,89);
upperBound = cvScalar(25,173,229);
CvCapture* capture = 0;
capture = cvCaptureFromCAM(1);
if(!capture)
{
printf("Could not initialize capturing...\n");
return -1;
}
cvNamedWindow("video");
cvNamedWindow("thresh");
// This image holds the "scribble" data...
// the tracked positions of the object
IplImage* imgScribble = NULL;
while(true)
{
IplImage* frame = 0;
frame = cvQueryFrame(capture);
if(!frame)
break;
// If this is the first frame, we need to initialize it
if(imgScribble == NULL)
{
imgScribble = cvCreateImage(cvGetSize(frame), 8, 3);
}
// Holds the thresholded image (tracked color -> white, the rest -> black)
IplImage* imgThresh = GetThresholdedImage(frame,lowerBound,upperBound);
// Calculate the moments to estimate the position of the object
CvMoments *moments = (CvMoments*)malloc(sizeof(CvMoments));
cvMoments(imgThresh, moments, 1);
// The actual moment values
double moment10 = cvGetSpatialMoment(moments, 1, 0);
double moment01 = cvGetSpatialMoment(moments, 0, 1);
double area = cvGetCentralMoment(moments, 0, 0);
// Holding the last and current positions
static int posX = 0;
static int posY = 0;
int lastX = posX;
int lastY = posY;
posX = moment10/area;
posY = moment01/area;
cout << "position = " << posX << " " << posY << endl;
// We want to draw a line only if its a valid position
if(lastX>0 && lastY>0 && posX>0 && posY>0)
{
// Draw a yellow line from the previous point to the current point
cvLine(imgScribble, cvPoint(posX, posY), cvPoint(lastX, lastY), upperBound, lineThickness);
}
// Add the scribbling image and the frame...
cvAdd(frame, imgScribble, frame);
cvShowImage("thresh", imgThresh);
cvShowImage("video", frame);
int c = cvWaitKey(10);
if(c==27) //ESC key
{
break;
}
cvReleaseImage(&imgThresh);
delete moments;
}
cvReleaseCapture(&capture);
return 0;
}

I don t know if I understand you right but I think you should need to add the following:
cvErode(imgThreshed, imgThreshed, NULL, 1);
cvDilate(imgThreshed, imgThreshed, NULL, 1);
in GetThresholdedImage and get less noise ! but after all I think it would be better for you to use the cv::Mat object of opencv ;)

Try BGS library, I used it before and like it. You can get it here: http://code.google.com/p/bgslibrary/

Related

mapping depth image to color image with realsense2 about opencv

I use librealsense2 library.
I refer to this site.. https://github.com/IntelRealSense/librealsense/blob/master/examples/align/rs-align.cpp
After mapping depth image to color image with realsense2 library,
I want to display the image with opencv Mat(imshow) function.
so i coded as..
#include "librealsense2/rs.hpp"
#include <opencv2/opencv.hpp>
#include <sstream>
#include <iostream>
#include <fstream>
#include <algorithm>
#include <cstring>
using namespace std;
using namespace cv;
void remove_background(rs2::video_frame& other, const rs2::depth_frame& depth_frame, float depth_scale, float clipping_dist);
float get_depth_scale(rs2::device dev);
rs2_stream find_stream_to_align(const std::vector<rs2::stream_profile>& streams);
bool profile_changed(const std::vector<rs2::stream_profile>& current, const std::vector<rs2::stream_profile>& prev);
int main(int args, char * argv[]) try
{
// Create and initialize GUI related objects
rs2::colorizer c;
rs2::config cfg;
rs2::pipeline pipe;
const int width = 1280;
const int height = 720;
c.set_option(RS2_OPTION_HISTOGRAM_EQUALIZATION_ENABLED, 1.f);
c.set_option(RS2_OPTION_COLOR_SCHEME, 2.f); // White to Black
cfg.enable_stream(RS2_STREAM_COLOR, width, height, RS2_FORMAT_BGR8, 30);
cfg.enable_stream(RS2_STREAM_DEPTH, width, height, RS2_FORMAT_Z16, 30);
rs2::pipeline_profile profile = pipe.start(cfg);
float depth_scale = get_depth_scale(profile.get_device());
rs2_stream align_to = find_stream_to_align(profile.get_streams());
rs2::align align(align_to);
float depth_clipping_distance = 3.f;
while (true)
{
rs2::frameset frameset = pipe.wait_for_frames();
if (profile_changed(pipe.get_active_profile().get_streams(), profile.get_streams()))
{
profile = pipe.get_active_profile();
align_to = find_stream_to_align(profile.get_streams());
align = rs2::align(align_to);
depth_scale = get_depth_scale(profile.get_device());
}
auto processed = align.process(frameset);
rs2::video_frame other_frame = processed.first(align_to);
rs2::depth_frame aligned_depth_frame = c(processed.get_depth_frame());
if (!aligned_depth_frame || !other_frame)
{
continue;
}
remove_background(other_frame, aligned_depth_frame, depth_scale, depth_clipping_distance);
Mat other_frameaM(Size(width, height), CV_8UC3, (void*)other_frame.get_data(), Mat::AUTO_STEP);
Mat aligned_depthM(Size(width, height), CV_8UC3, (void*)aligned_depth_frame.get_data(), Mat::AUTO_STEP);
namedWindow("other window", WINDOW_AUTOSIZE);
namedWindow("depth window", WINDOW_AUTOSIZE);
imshow("other window", other_frameaM);
imshow("depth window", aligned_depthM);
}
return EXIT_SUCCESS;
}
catch (const rs2::error & e)
{
std::cerr << "RealSense error calling " << e.get_failed_function() << "(" << e.get_failed_args() << "):\n " << e.what() << std::endl;
return EXIT_FAILURE;
}
catch (const std::exception & e)
{
std::cerr << e.what() << std::endl;
return EXIT_FAILURE;
}
float get_depth_scale(rs2::device dev)
{
// Go over the device's sensors
for (rs2::sensor& sensor : dev.query_sensors())
{
// Check if the sensor if a depth sensor
if (rs2::depth_sensor dpt = sensor.as<rs2::depth_sensor>())
{
return dpt.get_depth_scale();
}
}
throw std::runtime_error("Device does not have a depth sensor");
}
void remove_background(rs2::video_frame& other_frame, const rs2::depth_frame& depth_frame, float depth_scale, float clipping_dist)
{
const uint16_t* p_depth_frame = reinterpret_cast<const uint16_t*>(depth_frame.get_data());
uint8_t* p_other_frame = reinterpret_cast<uint8_t*>(const_cast<void*>(other_frame.get_data()));
int width = other_frame.get_width();
int height = other_frame.get_height();
int other_bpp = other_frame.get_bytes_per_pixel();
#pragma omp parallel for schedule(dynamic) //Using OpenMP to try to parallelise the loop
for (int y = 0; y < height; y++)
{
auto depth_pixel_index = y * width;
for (int x = 0; x < width; x++, ++depth_pixel_index)
{
// Get the depth value of the current pixel
auto pixels_distance = depth_scale * p_depth_frame[depth_pixel_index];
// Check if the depth value is invalid (<=0) or greater than the threashold
if (pixels_distance <= 0.f || pixels_distance > clipping_dist)
{
// Calculate the offset in other frame's buffer to current pixel
auto offset = depth_pixel_index * other_bpp;
// Set pixel to "background" color (0x999999)
std::memset(&p_other_frame[offset], 0x99, other_bpp);
}
}
}
}
rs2_stream find_stream_to_align(const std::vector<rs2::stream_profile>& streams)
{
//Given a vector of streams, we try to find a depth stream and another stream to align depth with.
//We prioritize color streams to make the view look better.
//If color is not available, we take another stream that (other than depth)
rs2_stream align_to = RS2_STREAM_ANY;
bool depth_stream_found = false;
bool color_stream_found = false;
for (rs2::stream_profile sp : streams)
{
rs2_stream profile_stream = sp.stream_type();
if (profile_stream != RS2_STREAM_DEPTH)
{
if (!color_stream_found) //Prefer color
align_to = profile_stream;
if (profile_stream == RS2_STREAM_COLOR)
{
color_stream_found = true;
}
}
else
{
depth_stream_found = true;
}
}
if (!depth_stream_found)
throw std::runtime_error("No Depth stream available");
if (align_to == RS2_STREAM_ANY)
throw std::runtime_error("No stream found to align with Depth");
return align_to;
}
bool profile_changed(const std::vector<rs2::stream_profile>& current, const std::vector<rs2::stream_profile>& prev)
{
for (auto&& sp : prev)
{
//If previous profile is in current (maybe just added another)
auto itr = std::find_if(std::begin(current), std::end(current), [&sp](const rs2::stream_profile& current_sp) { return sp.unique_id() == current_sp.unique_id(); });
if (itr == std::end(current)) //If it previous stream wasn't found in current
{
return true;
}
}
return false;
}
There are only gray screens and nothing happens.
Mat other_frameaM(Size(width, height), CV_8UC3, (void*)other_frame.get_data(), Mat::AUTO_STEP);
Mat aligned_depthM(Size(width, height), CV_8UC3, (void*)aligned_depth_frame.get_data(), Mat::AUTO_STEP);
I guess there are no problem. because the depth image and rgb image were opened well in CV_8UC3 format.
However, when I try to calibrate and then I got it in opencv, the image appears only in gray screen.
auto frames = pipe.wait_for_frames(); // Wait for next set of frames from the camera
rs2::video_frame color = frames.get_color_frame();
rs2::depth_frame depth = color_map(frames.get_depth_frame());
if (!color)
color = frames.get_infrared_frame();
Mat colorM(Size(width, height), CV_8UC3, (void*)color.get_data(), Mat::AUTO_STEP);
Mat depthM(Size(width, height), CV_8UC3, (void*)depth.get_data(), Mat::AUTO_STEP);
It is a part of code that output color image and depth image.
This works well.
so I guess..
rs2::video_frame other_frame = processed.first(align_to);
rs2::depth_frame aligned_depth_frame = c(processed.get_depth_frame());
Whatever the process, I thought it would run because it fetches it in frame format. I think I have a very big mistake on this code side.
Which part is wrong?
enter image description here
There are several ways to store an image in memory. There is no guarantee that you can just pass the buffer and it'll all work. try to copy pixel by pixel.
You should know that OpenCV uses BGR interleaved image format, while realsense might use another.
1) Get aligned frames
frameset data = pipe.wait_for_frames();
frameset aligned_set = align_to.process(data);
auto color_mat = frame_to_mat(aligned_set.get_color_frame());
auto depth_mat = frame_to_mat(aligned_set.get_depth_frame());
2) frame_to_mat helper function
cv::Mat frame_to_mat(const rs2::frame& f)
{
using namespace cv;
using namespace rs2;
auto vf = f.as<video_frame>();
const int w = vf.get_width();
const int h = vf.get_height();
if (f.get_profile().format() == RS2_FORMAT_BGR8)
{
return Mat(Size(w, h), CV_8UC3, (void*)f.get_data(), Mat::AUTO_STEP);
}
else if (f.get_profile().format() == RS2_FORMAT_RGB8)
{
auto r = Mat(Size(w, h), CV_8UC3, (void*)f.get_data(), Mat::AUTO_STEP);
cvtColor(r, r, CV_RGB2BGR);
return r;
}
else if (f.get_profile().format() == RS2_FORMAT_Z16)
{
return Mat(Size(w, h), CV_16UC1, (void*)f.get_data(), Mat::AUTO_STEP);
}
else if (f.get_profile().format() == RS2_FORMAT_Y8)
{
return Mat(Size(w, h), CV_8UC1, (void*)f.get_data(), Mat::AUTO_STEP);
}
throw std::runtime_error("Frame format is not supported yet!");
}

Detetcting intersection between 2 line in webcam feed opencv

i'm trying to detect the intersection between two line in webcam feed. Here's the screenshot of what i already have
I try to find the intersection between my red and green line.
And here's the code of what i already have
#include "stdafx.h"
#include <cv.h>
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <highgui.h>
IplImage* imgTracking;
int lastX = -1;
int lastY = -1;
//This function threshold the HSV image and create a binary image
IplImage* GetThresholdedImage(IplImage* imgHSV){
IplImage* imgThresh=cvCreateImage(cvGetSize(imgHSV),IPL_DEPTH_8U, 1);
cvInRangeS(imgHSV, cvScalar(170,160,60), cvScalar(180,2556,256), imgThresh);
return imgThresh;
}
void trackObject(IplImage* imgThresh){
// Calculate the moments of 'imgThresh'
CvMoments *moments = (CvMoments*)malloc(sizeof(CvMoments));
cvMoments(imgThresh, moments, 1);
double moment10 = cvGetSpatialMoment(moments, 1, 0);
double moment01 = cvGetSpatialMoment(moments, 0, 1);
double area = cvGetCentralMoment(moments, 0, 0);
// if the area<1000, I consider that the there are no object in the image and it's because of the noise, the area is not zero
if(area>1000){
// calculate the position of the ball
int posX = moment10/area;
int posY = moment01/area;
if(lastX>=0 && lastY>=0 && posX>=0 && posY>=0)
{
// Draw a yellow line from the previous point to the current point
cvLine(imgTracking, cvPoint(posX, posY), cvPoint(lastX, lastY), cvScalar(0,0,255), 4);
}
lastX = posX;
lastY = posY;
}
cvLine(imgTracking,cv::Point(100,300) , cv::Point(600,300),cv::Scalar(0,200,0),2,8);
free(moments);
}
bool intersection(cv::Point lastX, cv::Point lastY, cv::Point , cv::Point())
{
}
/*
void imaginaryline()
{
cv::Mat img = cv::Mat::zeros(500, 500, CV_8UC3);
cv::line(img, cv::Point(100,200) , cv::Point(400,100),cv::Scalar(0,200,0),2,8);
}*/
int main(){
CvCapture* capture =0;
capture = cvCaptureFromCAM(0);
if(!capture){
printf("Capture failure\n");
return -1;
}
IplImage* frame=0;
frame = cvQueryFrame(capture);
if(!frame) return -1;
//create a blank image and assigned to 'imgTracking' which has the same size of original video
imgTracking=cvCreateImage(cvGetSize(frame),IPL_DEPTH_8U, 3);
cvZero(imgTracking); //covert the image, 'imgTracking' to black
cvNamedWindow("Video");
cvNamedWindow("Ball");
//iterate through each frames of the video
while(true){
frame = cvQueryFrame(capture);
if(!frame) break;
frame=cvCloneImage(frame);
cvSmooth(frame, frame, CV_GAUSSIAN,3,3); //smooth the original image using Gaussian kernel
IplImage* imgHSV = cvCreateImage(cvGetSize(frame), IPL_DEPTH_8U, 3);
cvCvtColor(frame, imgHSV, CV_BGR2HSV); //Change the color format from BGR to HSV
IplImage* imgThresh = GetThresholdedImage(imgHSV);
cvSmooth(imgThresh, imgThresh, CV_GAUSSIAN,3,3); //smooth the binary image using Gaussian kernel
//track the possition of the ball
trackObject(imgThresh);
printf("Pos X = %d", lastX);
printf("Pos Y = %d", lastY);
// Add the tracking image and the frame
cvAdd(frame, imgTracking, frame);
cvShowImage("Ball", imgThresh);
cvShowImage("Video", frame);
//Clean up used images
cvReleaseImage(&imgHSV);
cvReleaseImage(&imgThresh);
cvReleaseImage(&frame);
//Wait 10mS
int c = cvWaitKey(10);
//If 'ESC' is pressed, break the loop
if((char)c==27 ) break;
}
cvDestroyAllWindows() ;
cvReleaseImage(&imgTracking);
cvReleaseCapture(&capture);
return 0;
}
Thank you for your attention guys, i waited for any of your response
UPDATE :
Thanks to Sebastian Schmitz, i sollved it. Here's my code
void checkIntersection(int line, int lastY, int y)
{
if(lastY << line && y >= line || lastY > line && y <= line)
{
printf("intersection detected");
}
}
void trackObject(IplImage* imgThresh){
// Calculate the moments of 'imgThresh'
CvMoments *moments = (CvMoments*)malloc(sizeof(CvMoments));
cvMoments(imgThresh, moments, 1);
double moment10 = cvGetSpatialMoment(moments, 1, 0);
double moment01 = cvGetSpatialMoment(moments, 0, 1);
double area = cvGetCentralMoment(moments, 0, 0);
// if the area<1000, I consider that the there are no object in the image and it's because of the noise, the area is not zero
if(area>1000){
// calculate the position of the ball
int posX = moment10/area;
int posY = moment01/area;
if(lastX>=0 && lastY>=0 && posX>=0 && posY>=0)
{
// Draw a yellow line from the previous point to the current point
cvLine(imgTracking, cvPoint(posX, posY), cvPoint(lastX, lastY), cvScalar(0,0,255), 4);
}
checkIntersection(300, lastY, posY);
lastX = posX;
lastY = posY;
}
cvLine(imgTracking,cv::Point(100,300) , cv::Point(600,300),cv::Scalar(0,200,0),2,8);
cvRectangle(imgTracking,cv::Point(400,400), cv::Point(450,450),cv::Scalar(0,200,0),2,8);
free(moments);
}
i put the call for checkintersection function inside trackobject function so i dont have to change variable posY into global which lead to many error.
Thank you all for your response
If the line is always perfectly horiontal, it will be enough to test if the y coordinate of your last point is on one side of the line and your current Point on the other:
//Pseudocode:
int line = 20; //horizontal line on y-coordinate "20"
while(tracking == true){
int lastY = posY;
int y = getCoordinate().getY(); //call the y-coordinate of your current point
checkIntersection(line, lastY, y)
}
checkIntersection(int line, int lastY, int y){
if(lastY < line && y >= line ||
lastY > line && y <= line ){
print("intersection detected")
//optional additional check if point is between endpoint of line if you have to
}
}

Calculate white areas pixels in contours using opencv and Javacv

I have develop a program to detect motions using JavaCV. up to now i have completed cvFindContours of the processed image. source code is given below,
public class MotionDetect {
public static void main(String args[]) throws Exception, InterruptedException {
//FFmpegFrameGrabber grabber = new FFmpegFrameGrabber(new File("D:/pool.avi"));
OpenCVFrameGrabber grabber = new OpenCVFrameGrabber("D:/2.avi");
final CanvasFrame canvas = new CanvasFrame("My Image");
final CanvasFrame canvas2 = new CanvasFrame("ROI");
canvas.setDefaultCloseOperation(javax.swing.JFrame.EXIT_ON_CLOSE);
grabber.start();
IplImage frame = grabber.grab();
CvSize imgsize = cvGetSize(frame);
IplImage grayImage = cvCreateImage(imgsize, IPL_DEPTH_8U, 1);
IplImage ROIFrame = cvCreateImage(cvSize((265 - 72), (214 - 148)), IPL_DEPTH_8U, 1);
IplImage colorImage;
IplImage movingAvg = cvCreateImage(imgsize, IPL_DEPTH_32F, 3);
IplImage difference = null;
IplImage temp = null;
IplImage motionHistory = cvCreateImage(imgsize, IPL_DEPTH_8U, 3);
CvRect bndRect = cvRect(0, 0, 0, 0);
CvPoint pt1 = new CvPoint(), pt2 = new CvPoint();
CvFont font = null;
//Capture the movie frame by frame.
int prevX = 0;
int numPeople = 0;
char[] wow = new char[65];
int avgX = 0;
//Indicates whether this is the first time in the loop of frames.
boolean first = true;
//Indicates the contour which was closest to the left boundary before the object
//entered the region between the buildings.
int closestToLeft = 0;
//Same as above, but for the right.
int closestToRight = 320;
while (true) {
colorImage = grabber.grab();
if (colorImage != null) {
if (first) {
difference = cvCloneImage(colorImage);
temp = cvCloneImage(colorImage);
cvConvertScale(colorImage, movingAvg, 1.0, 0.0);
first = false;
//cvShowImage("My Window1", difference);
} //else, make a running average of the motion.
else {
cvRunningAvg(colorImage, movingAvg, 0.020, null);
}
//Convert the scale of the moving average.
cvConvertScale(movingAvg, temp, 1.0, 0.0);
//Minus the current frame from the moving average.
cvAbsDiff(colorImage, temp, difference);
//Convert the image to grayscale.
cvCvtColor(difference, grayImage, CV_RGB2GRAY);
//canvas.showImage(grayImage);
//Convert the image to black and white.
cvThreshold(grayImage, grayImage, 70, 255, CV_THRESH_BINARY);
//Dilate and erode to get people blobs
cvDilate(grayImage, grayImage, null, 18);
cvErode(grayImage, grayImage, null, 10);
canvas.showImage(grayImage);
ROIFrame = cvCloneImage(grayImage);
cvSetImageROI(ROIFrame, cvRect(72, 148, (265 - 72), (214 - 148)));
//cvOr(outFrame, tempFrame, outFrame);
cvShowImage("ROI Frame", ROIFrame);
cvRectangle(colorImage, /* the dest image */
cvPoint(72, 148), /* top left point */
cvPoint(265, 214), /* bottom right point */
cvScalar(255, 0, 0, 0), /* the color; blue */
1, 8, 0);
CvMemStorage storage = cvCreateMemStorage(0);
CvSeq contour = new CvSeq(null);
cvFindContours(grayImage, storage, contour, Loader.sizeof(CvContour.class), CV_RETR_CCOMP, CV_CHAIN_APPROX_SIMPLE);
}
//Show the frame.
cvShowImage("My Window", colorImage);
//Wait for the user to see it.
cvWaitKey(10);
}
//If this is the first time, initialize the images.
//Thread.sleep(50);
}
}
}
In this code ROIFrame, i need to calculate white contours area or pixel numbers??.. is there any way that i can proceed with
Use the function cvContourArea() Documentation here.
In your code, after your cvFindContours, do a loop with all of your contours like as:
CvSeq* curr_contour = contour;
while (curr_contour != NULL) {
area = fabs(cvContourArea(curr_contour,CV_WHOLE_SEQ, 0));
current_contour = current_contour->h_next;
}
Don't forget to store the area somewhere.

Online Face Recognition using OpenCV

I am trying to implement online face recognition using the webcam. I am using this two websites as references
shervinemami.co.cc
cognotics.com
I have few questions:
In face recognition, there are 6 steps:
Grab a frame from the camera
Detect a face within the image
Crop the frame to show just the face
Convert the frame to greyscale
Preprocess the image
Recognize the person in the image.
I am able to do the first five steps. Last step i am not able to do. I am not sure how to link step 5 to step 6.
I have already created the train.txt file and test.txt file which contains the information of the training and testing images. I have already added the functions such as learn(), doPCA() to the code...
But the point is how to use these functions in the main to recognize the image that is already preprocessed.
Need some help on it...
Attached the code below:
// Real-time.cpp : Defines the entry point for the console application.
#include "stdafx.h"
#include <cv.h>
#include <cxcore.h>
#include <highgui.h>
#include <cvaux.h>
IplImage ** faceImgArr = 0; // array of face images
CvMat * personNumTruthMat = 0; // array of person numbers
int nTrainFaces = 0; // the number of training images
int nEigens = 0; // the number of eigenvalues
IplImage * pAvgTrainImg = 0; // the average image
IplImage ** eigenVectArr = 0; // eigenvectors
CvMat * eigenValMat = 0; // eigenvalues
CvMat * projectedTrainFaceMat = 0; // projected training faces
IplImage* getCameraFrame(CvCapture* &camera);
IplImage* detectFaces( IplImage *img ,CvHaarClassifierCascade* facecascade,CvMemStorage* storage );
CvRect detectFaceInImage(IplImage *inputImg, CvHaarClassifierCascade* cascade);
IplImage* preprocess( IplImage* inputImg);
IplImage* resizeImage(const IplImage *origImg, int newWidth,
int newHeight, bool keepAspectRatio);
void learn();
void recognize();
void doPCA();
void storeTrainingData();
int loadTrainingData(CvMat ** pTrainPersonNumMat);
int findNearestNeighbor(float * projectedTestFace);
int loadFaceImgArray(char * filename);
int _tmain(int argc, _TCHAR* argv[])
{
CvCapture* camera = 0; // The camera device.
CvMemStorage *storage;
cvNamedWindow( "Realtime:", CV_WINDOW_AUTOSIZE);
char *faceCascadeFilename = "C:/OpenCV2.1/data/haarcascades/haarcascade_frontalface_alt.xml";
CvHaarClassifierCascade* faceCascade;
faceCascade = (CvHaarClassifierCascade*)cvLoad(faceCascadeFilename, 0, 0, 0);
storage = cvCreateMemStorage( 0 );
learn();
while ( cvWaitKey(10) != 27 ) // Quit on "Escape" key
{
IplImage *frame = getCameraFrame(camera);
//IplImage* resized=cvCreateImage(cvSize(420,240),frame->depth,3);
//cvResizeWindow( "Image:", 640, 480);
//cvResize(frame,resized);
//cvShowImage( "Realtime:", resized );
IplImage *imgA = resizeImage(frame, 420,240, true);
IplImage *frame1 = detectFaces(imgA,faceCascade,storage);
frame1 = preprocess(frame1);
}
// Free the camera.
cvReleaseCapture( &camera );
cvReleaseMemStorage( &storage );
return 0;
}
IplImage* getCameraFrame(CvCapture* &camera)
{
IplImage *frame;
int w, h;
// If the camera hasn't been initialized, then open it.
if (!camera) {
printf("Acessing the camera ...\n");
camera = cvCreateCameraCapture( 0 );
if (!camera) {
printf("Couldn't access the camera.\n");
exit(1);
}
// Try to set the camera resolution to 320 x 240.
cvSetCaptureProperty(camera, CV_CAP_PROP_FRAME_WIDTH, 320);
cvSetCaptureProperty(camera, CV_CAP_PROP_FRAME_HEIGHT, 240);
// Get the first frame, to make sure the camera is initialized.
frame = cvQueryFrame( camera );
if (frame) {
w = frame->width;
h = frame->height;
printf("Got the camera at %dx%d resolution.\n", w, h);
}
// Wait a little, so that the camera can auto-adjust its brightness.
Sleep(1000); // (in milliseconds)
}
// Wait until the next camera frame is ready, then grab it.
frame = cvQueryFrame( camera );
if (!frame) {
printf("Couldn't grab a camera frame.\n");
exit(1);
}
return frame;
}
CvRect detectFaceInImage(IplImage *inputImg, CvHaarClassifierCascade* cascade)
{
// Smallest face size.
CvSize minFeatureSize = cvSize(20, 20);
// Only search for 1 face.
int flags = CV_HAAR_FIND_BIGGEST_OBJECT | CV_HAAR_DO_ROUGH_SEARCH;
// How detailed should the search be.
float search_scale_factor = 1.1f;
IplImage *detectImg;
IplImage *greyImg = 0;
CvMemStorage* storage;
CvRect rc;
double t;
CvSeq* rects;
CvSize size;
int i, ms, nFaces;
storage = cvCreateMemStorage(0);
cvClearMemStorage( storage );
// If the image is color, use a greyscale copy of the image.
detectImg = (IplImage*)inputImg;
if (inputImg->nChannels > 1) {
size = cvSize(inputImg->width, inputImg->height);
greyImg = cvCreateImage(size, IPL_DEPTH_8U, 1 );
cvCvtColor( inputImg, greyImg, CV_BGR2GRAY );
detectImg = greyImg; // Use the greyscale image.
}
// Detect all the faces in the greyscale image.
t = (double)cvGetTickCount();
rects = cvHaarDetectObjects( detectImg, cascade, storage,
search_scale_factor, 3, flags, minFeatureSize);
t = (double)cvGetTickCount() - t;
ms = cvRound( t / ((double)cvGetTickFrequency() * 1000.0) );
nFaces = rects->total;
printf("Face Detection took %d ms and found %d objects\n", ms, nFaces);
// Get the first detected face (the biggest).
if (nFaces > 0)
rc = *(CvRect*)cvGetSeqElem( rects, 0 );
else
rc = cvRect(-1,-1,-1,-1); // Couldn't find the face.
if (greyImg)
cvReleaseImage( &greyImg );
cvReleaseMemStorage( &storage );
//cvReleaseHaarClassifierCascade( &cascade );
return rc; // Return the biggest face found, or (-1,-1,-1,-1).
}
IplImage* detectFaces( IplImage *img ,CvHaarClassifierCascade* facecascade,CvMemStorage* storage )
{
int i;
CvRect *r;
CvSeq *faces = cvHaarDetectObjects(
img,
facecascade,
storage,
1.1,
3,
0 /*CV_HAAR_DO_CANNY_PRUNNING*/,
cvSize( 40, 40 ) );
int padding_width = 30; // pixels
int padding_height = 30; // pixels
for( i = 0 ; i < ( faces ? faces->total : 0 ) ; i++ ) {
r = ( CvRect* )cvGetSeqElem( faces, i );
cvRectangle( img,
cvPoint( r->x, r->y ),
cvPoint( r->x + r->width, r->y + r->height ),
CV_RGB( 255, 0, 0 ), 1, 8, 0 );
}
cvShowImage( "Realtime:", img );
//cropping the face
cvSetImageROI(img, cvRect(r->x,r->y,r->width,r->height));
IplImage *img2 = cvCreateImage(cvGetSize(img),
img->depth,
img->nChannels);
cvCopy(img, img2, NULL);
cvResetImageROI(img);
return img;
}
IplImage* preprocess( IplImage* inputImg){
IplImage *detectImg, *greyImg = 0;
IplImage *imageProcessed;
CvSize size;
detectImg = (IplImage*)inputImg;
if (inputImg->nChannels > 1) {
size = cvSize(inputImg->width, inputImg->height);
greyImg = cvCreateImage(size, IPL_DEPTH_8U, 1 );
cvCvtColor( inputImg, greyImg, CV_BGR2GRAY );
detectImg = greyImg; // Use the greyscale image.
}
imageProcessed = cvCreateImage(cvSize(inputImg->width, inputImg->height), IPL_DEPTH_8U, 1);
cvResize(detectImg, imageProcessed, CV_INTER_LINEAR);
cvEqualizeHist(imageProcessed, imageProcessed);
return imageProcessed;
}
IplImage* resizeImage(const IplImage *origImg, int newWidth,
int newHeight, bool keepAspectRatio)
{
IplImage *outImg = 0;
int origWidth;
int origHeight;
if (origImg) {
origWidth = origImg->width;
origHeight = origImg->height;
}
if (newWidth <= 0 || newHeight <= 0 || origImg == 0
|| origWidth <= 0 || origHeight <= 0) {
//cerr << "ERROR: Bad desired image size of " << newWidth
// << "x" << newHeight << " in resizeImage().\n";
exit(1);
}
if (keepAspectRatio) {
// Resize the image without changing its aspect ratio,
// by cropping off the edges and enlarging the middle section.
CvRect r;
// input aspect ratio
float origAspect = (origWidth / (float)origHeight);
// output aspect ratio
float newAspect = (newWidth / (float)newHeight);
// crop width to be origHeight * newAspect
if (origAspect > newAspect) {
int tw = (origHeight * newWidth) / newHeight;
r = cvRect((origWidth - tw)/2, 0, tw, origHeight);
}
else { // crop height to be origWidth / newAspect
int th = (origWidth * newHeight) / newWidth;
r = cvRect(0, (origHeight - th)/2, origWidth, th);
}
IplImage *croppedImg = cropImage(origImg, r);
// Call this function again, with the new aspect ratio image.
// Will do a scaled image resize with the correct aspect ratio.
outImg = resizeImage(croppedImg, newWidth, newHeight, false);
cvReleaseImage( &croppedImg );
}
else {
// Scale the image to the new dimensions,
// even if the aspect ratio will be changed.
outImg = cvCreateImage(cvSize(newWidth, newHeight),
origImg->depth, origImg->nChannels);
if (newWidth > origImg->width && newHeight > origImg->height) {
// Make the image larger
cvResetImageROI((IplImage*)origImg);
// CV_INTER_LINEAR: good at enlarging.
// CV_INTER_CUBIC: good at enlarging.
cvResize(origImg, outImg, CV_INTER_LINEAR);
}
else {
// Make the image smaller
cvResetImageROI((IplImage*)origImg);
// CV_INTER_AREA: good at shrinking (decimation) only.
cvResize(origImg, outImg, CV_INTER_AREA);
}
}
return outImg;
}
void learn()
{
int i, offset;
// load training data
nTrainFaces = loadFaceImgArray("C:/Users/HP/Desktop/OpenCV/50_images_of_15_people.txt");
if( nTrainFaces < 2 )
{
fprintf(stderr,
"Need 2 or more training faces\n"
"Input file contains only %d\n", nTrainFaces);
return;
}
// do PCA on the training faces
doPCA();
// project the training images onto the PCA subspace
projectedTrainFaceMat = cvCreateMat( nTrainFaces, nEigens, CV_32FC1 );
offset = projectedTrainFaceMat->step / sizeof(float);
for(i=0; i<nTrainFaces; i++)
{
//int offset = i * nEigens;
cvEigenDecomposite(
faceImgArr[i],
nEigens,
eigenVectArr,
0, 0,
pAvgTrainImg,
//projectedTrainFaceMat->data.fl + i*nEigens);
projectedTrainFaceMat->data.fl + i*offset);
}
// store the recognition data as an xml file
storeTrainingData();
}
void recognize()
{
int i, nTestFaces = 0; // the number of test images
CvMat * trainPersonNumMat = 0; // the person numbers during training
float * projectedTestFace = 0;
// load test images and ground truth for person number
nTestFaces = loadFaceImgArray("C:/Users/HP/Desktop/OpenCV/test.txt");
printf("%d test faces loaded\n", nTestFaces);
// load the saved training data
if( !loadTrainingData( &trainPersonNumMat ) ) return;
// project the test images onto the PCA subspace
projectedTestFace = (float *)cvAlloc( nEigens*sizeof(float) );
for(i=0; i<nTestFaces; i++)
{
int iNearest, nearest, truth;
// project the test image onto the PCA subspace
cvEigenDecomposite(
faceImgArr[i],
nEigens,
eigenVectArr,
0, 0,
pAvgTrainImg,
projectedTestFace);
iNearest = findNearestNeighbor(projectedTestFace);
truth = personNumTruthMat->data.i[i];
nearest = trainPersonNumMat->data.i[iNearest];
printf("nearest = %d, Truth = %d\n", nearest, truth);
}
}
int loadTrainingData(CvMat ** pTrainPersonNumMat)
{
CvFileStorage * fileStorage;
int i;
// create a file-storage interface
fileStorage = cvOpenFileStorage( "facedata.xml", 0, CV_STORAGE_READ );
if( !fileStorage )
{
fprintf(stderr, "Can't open facedata.xml\n");
return 0;
}
nEigens = cvReadIntByName(fileStorage, 0, "nEigens", 0);
nTrainFaces = cvReadIntByName(fileStorage, 0, "nTrainFaces", 0);
*pTrainPersonNumMat = (CvMat *)cvReadByName(fileStorage, 0, "trainPersonNumMat", 0);
eigenValMat = (CvMat *)cvReadByName(fileStorage, 0, "eigenValMat", 0);
projectedTrainFaceMat = (CvMat *)cvReadByName(fileStorage, 0, "projectedTrainFaceMat", 0);
pAvgTrainImg = (IplImage *)cvReadByName(fileStorage, 0, "avgTrainImg", 0);
eigenVectArr = (IplImage **)cvAlloc(nTrainFaces*sizeof(IplImage *));
for(i=0; i<nEigens; i++)
{
char varname[200];
sprintf( varname, "eigenVect_%d", i );
eigenVectArr[i] = (IplImage *)cvReadByName(fileStorage, 0, varname, 0);
}
// release the file-storage interface
cvReleaseFileStorage( &fileStorage );
return 1;
}
void storeTrainingData()
{
CvFileStorage * fileStorage;
int i;
// create a file-storage interface
fileStorage = cvOpenFileStorage( "facedata.xml", 0, CV_STORAGE_WRITE );
// store all the data
cvWriteInt( fileStorage, "nEigens", nEigens );
cvWriteInt( fileStorage, "nTrainFaces", nTrainFaces );
cvWrite(fileStorage, "trainPersonNumMat", personNumTruthMat, cvAttrList(0,0));
cvWrite(fileStorage, "eigenValMat", eigenValMat, cvAttrList(0,0));
cvWrite(fileStorage, "projectedTrainFaceMat", projectedTrainFaceMat, cvAttrList(0,0));
cvWrite(fileStorage, "avgTrainImg", pAvgTrainImg, cvAttrList(0,0));
for(i=0; i<nEigens; i++)
{
char varname[200];
sprintf( varname, "eigenVect_%d", i );
cvWrite(fileStorage, varname, eigenVectArr[i], cvAttrList(0,0));
}
// release the file-storage interface
cvReleaseFileStorage( &fileStorage );
}
int findNearestNeighbor(float * projectedTestFace)
{
//double leastDistSq = 1e12;
double leastDistSq = DBL_MAX;
int i, iTrain, iNearest = 0;
for(iTrain=0; iTrain<nTrainFaces; iTrain++)
{
double distSq=0;
for(i=0; i<nEigens; i++)
{
float d_i =
projectedTestFace[i] -
projectedTrainFaceMat->data.fl[iTrain*nEigens + i];
//distSq += d_i*d_i / eigenValMat->data.fl[i]; // Mahalanobis
distSq += d_i*d_i; // Euclidean
}
if(distSq < leastDistSq)
{
leastDistSq = distSq;
iNearest = iTrain;
}
}
return iNearest;
}
void doPCA()
{
int i;
CvTermCriteria calcLimit;
CvSize faceImgSize;
// set the number of eigenvalues to use
nEigens = nTrainFaces-1;
// allocate the eigenvector images
faceImgSize.width = faceImgArr[0]->width;
faceImgSize.height = faceImgArr[0]->height;
eigenVectArr = (IplImage**)cvAlloc(sizeof(IplImage*) * nEigens);
for(i=0; i<nEigens; i++)
eigenVectArr[i] = cvCreateImage(faceImgSize, IPL_DEPTH_32F, 1);
// allocate the eigenvalue array
eigenValMat = cvCreateMat( 1, nEigens, CV_32FC1 );
// allocate the averaged image
pAvgTrainImg = cvCreateImage(faceImgSize, IPL_DEPTH_32F, 1);
// set the PCA termination criterion
calcLimit = cvTermCriteria( CV_TERMCRIT_ITER, nEigens, 1);
// compute average image, eigenvalues, and eigenvectors
cvCalcEigenObjects(
nTrainFaces,
(void*)faceImgArr,
(void*)eigenVectArr,
CV_EIGOBJ_NO_CALLBACK,
0,
0,
&calcLimit,
pAvgTrainImg,
eigenValMat->data.fl);
cvNormalize(eigenValMat, eigenValMat, 1, 0, CV_L1, 0);
}
int loadFaceImgArray(char * filename)
{
FILE * imgListFile = 0;
char imgFilename[512];
int iFace, nFaces=0;
// open the input file
if( !(imgListFile = fopen(filename, "r")) )
{
fprintf(stderr, "Can\'t open file %s\n", filename);
return 0;
}
// count the number of faces
while( fgets(imgFilename, 512, imgListFile) ) ++nFaces;
rewind(imgListFile);
// allocate the face-image array and person number matrix
faceImgArr = (IplImage **)cvAlloc( nFaces*sizeof(IplImage *) );
personNumTruthMat = cvCreateMat( 1, nFaces, CV_32SC1 );
// store the face images in an array
for(iFace=0; iFace<nFaces; iFace++)
{
// read person number and name of image file
fscanf(imgListFile,
"%d %s", personNumTruthMat->data.i+iFace, imgFilename);
// load the face image
faceImgArr[iFace] = cvLoadImage(imgFilename, CV_LOAD_IMAGE_GRAYSCALE);
if( !faceImgArr[iFace] )
{
fprintf(stderr, "Can\'t load image from %s\n", imgFilename);
return 0;
}
}
fclose(imgListFile);
return nFaces;
}
My answer may came late but it might be useful for pals if i answer it.I am working on a similar project and i have faced the same problem.I solved it by writing a function the saves or write the detected,cropped and preprocessed image on to the hard disk of my computer(Using CvWrite).And feeding the parameter of the saved images to the recognition part of the code. It has made my life easier.It has been a bit harder for me to to pass the parameters of the rect of the region of interest. If you or someone else did this it might be great sharing the code with us.
You can use the following code to save the image after resizing it to a constant value using the resizeimage function on you code.
void saveCroppedFaces(CvSeq* tempon,IplImage* DetectedImage)
{
char* name;
int nFaces;
CvRect rect;
nFaces=tempon->total;
name =new char[nFaces];
IplImage* cropped = 0;
IplImage* croppedResized=0;
Mat croped;
for(int k=0;k<nFaces;k++)
{
itoa(k,(name+k),10);
rect = *(CvRect*)cvGetSeqElem( tempon, k );
cropped= cropImage(DetectedImage,rect);
//i can resize the cropped faces in to a fixed size here
//i can write a function to save images and call it so
//that it will save it in to hard drive
//cvNamedWindow((name+k),CV_WINDOW_AUTOSIZE);
//cvShowImage((name+k),cropped);
croppedResized=resizeImage(cropped,60,60);
croped=IplToMatConverter(croppedResized);
saveROI(croped,itoa(k,(name+k),10));
cvReleaseImage(&cropped);
}
name=NULL;
delete[] name;
}
void saveROI(Mat mat,String outputFileName)
{
string store_path("C://Users/sizusuzu/Desktop/Images/FaceDetection2
/"+outputFileName+".jpg");
bool write_success = imwrite(store_path,mat);
}
After this you can change the IplImage* to Mat using
Mat IplToMatConverter(IplImage* imageToMat)
{
Mat mat = cvarrToMat(imageToMat);
return mat;
}
And use the Mat in FaceRecognizer API.Or just do the other/harder way.
Thanks
I just read
int _tmain(int argc, _TCHAR* argv[])
{
.......
}
part of your code. This code is used for detecting the face in the image. Lets say it is Face_x. Now extract features from Face_x, call it as F_x. In your database, you should store features {F_1, F_2,..., F_N} extracted from n different faces {Face_1, Face_2,..Face_N}.
Simple algorithm to recognize Face_x is to calculate Euclidean distances between F_x and n features. The minimum distance (below threshold) gives corresponding face. If the minimum distance is not below threshold then Face_x is a new face. Add feature F_x to database. This way you can increase your database. You can begin your algorithm with no features in database. With each new face, database grows.
I hope the method suggested by me will lead you to the solution

Adjust code to detect multiple circles instead of just 1 in OPENCV

I have got this circle detection working but only detects 1 circle. How would I adjust code to detect multiple circles(max circles that will be detected is 22 as using it for snooker). I presume i would be editing the circle detectoin method but i am stuck:(
#include <stdio.h>
#include "cv.h"
#include "highgui.h"
#include <iostream>
#include <math.h>
#include <string.h>
#include <conio.h>
using namespace std;
IplImage* img = 0;
CvMemStorage * cstorage;
CvMemStorage * hstorage;
void detectCircle( IplImage *frame );
int main( int argc, char **argv )
{
CvCapture *capture = 0;
IplImage *frame = 0;
int key = 0;
hstorage = cvCreateMemStorage( 0 );
cstorage = cvCreateMemStorage( 0 );
//CvVideoWriter *writer = 0;
//int colour = 1;
//int fps = 25;
//int frameW = 640;
//int frameH = 480;
//writer = cvCreateVideoWriter("test.avi",CV_FOURCC('P', 'I', 'M', '1'),fps,cvSize(frameW,frameH),colour);
//initialise camera
capture = cvCaptureFromCAM( 0 );
//check if camera present
if ( !capture )
{
fprintf( stderr, "cannot open webcam\n");
return 1;
}
//create a window
cvNamedWindow( "Snooker", CV_WINDOW_AUTOSIZE );
while(key !='q')
{
//get frame
frame = cvQueryFrame(capture);
//int nFrames = 50;
//for (int i=0; i<nFrames;i++){
//cvGrabFrame(capture);
//frame = cvRetrieveFrame(capture);
//cvWriteFrame(writer, frame);
//}
//check for frame
if( !frame ) break;
detectCircle(frame);
//display current frame
//cvShowImage ("Snooker", frame );
//exit if Q pressed
key = cvWaitKey( 20 );
}
// free memory
cvDestroyWindow( "Snooker" );
cvReleaseCapture( &capture );
cvReleaseMemStorage( &cstorage);
cvReleaseMemStorage( &hstorage);
//cvReleaseVideoWriter(&writer);
return 0;
}
**void detectCircle( IplImage * img )
{
int px;
int py;
int edge_thresh = 1;
IplImage *gray = cvCreateImage( cvSize(img->width,img->height), 8, 1);
IplImage *edge = cvCreateImage( cvSize(img->width,img->height), 8, 1);
cvCvtColor(img, gray, CV_BGR2GRAY);
gray->origin = 1;
// color threshold
cvThreshold(gray,gray,100,255,CV_THRESH_BINARY);
// smooths out image
cvSmooth(gray, gray, CV_GAUSSIAN, 11, 11);
// get edges
cvCanny(gray, edge, (float)edge_thresh, (float)edge_thresh*3, 5);
// detects circle
CvSeq* circle = cvHoughCircles(gray, cstorage, CV_HOUGH_GRADIENT, 1, gray->height/50, 5, 35);
// draws circle and its centerpoint
float* p = (float*)cvGetSeqElem( circle, 0 );
if( p==null ){ return;}
cvCircle( img, cvPoint(cvRound(p[0]),cvRound(p[1])), 3, CV_RGB(255,0,0), -1, 8, 0 );
cvCircle( img, cvPoint(cvRound(p[0]),cvRound(p[1])), cvRound(p[2]), CV_RGB(200,0,0), 1, 8, 0 );
px=cvRound(p[0]);
py=cvRound(p[1]);**
cvShowImage ("Snooker", img );
}
Your code finds all circles - you just draw one:
// draws circle and its centerpoint
float* p = (float*)cvGetSeqElem( circle, 0 );
if( p==null ){ return;}
cvCircle( img, cvPoint(cvRound(p[0]),cvRound(p[1])), 3, CV_RGB(255,0,0), -1, 8, 0 );
cvCircle( img, cvPoint(cvRound(p[0]),cvRound(p[1])), cvRound(p[2]), CV_RGB(200,0,0), 1, 8, 0);
px=cvRound(p[0]);
py=cvRound(p[1]);
You should do it in cycle, something like:
for( int i=0; i < circles->total; i++ )
{
float* p = (float*) cvGetSeqElem( circles, i );
// ... d draw staff
}

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