iOS using openCV to apply color and texture to walls

C++
1

am using openCV to apply color textures to a wall. When the size of the image is more than 150 Kb then I am able to do the same but when the size of the image is less than 100 kb it doesn’t work properly. If I click on the image it doesn’t work if I click on top of it works. I am assuming it has something to with the dimensions of the image and the screen and the seed point but dont know in which direction to proceed. I am posting the code used below. Any pointers will be really appreciated and if more details are required will update this question

#include “WallPainter.hpp”

using namespace cv;
using namespace std;

Mat WallPainter::paint_wall(Mat image,Point p, cv::Size imageSize, cv::Scalar chosenColor) {

double cannyMinThres = 30.0;
double ratio = 2.5;

Mat mRgbMat = image;

cvtColor(mRgbMat,mRgbMat,COLOR_RGBA2RGB);

Mat mask = Mat(Size(mRgbMat.cols/8.0, mRgbMat.rows/8.0), CV_8UC1, Scalar(0.0));

Mat img ;
mRgbMat.copyTo(img);

Mat mGreyScaleMat;
cvtColor(mRgbMat, mGreyScaleMat,COLOR_RGB2GRAY, 3);
medianBlur(mGreyScaleMat,mGreyScaleMat,3);


Mat cannyGreyMat;
Canny(mGreyScaleMat, cannyGreyMat, cannyMinThres, cannyMinThres*ratio, 3);

//hsv
Mat hsvImage;
cvtColor(img,hsvImage,COLOR_RGB2HSV);

//got the hsv values
vector<Mat> list = vector<Mat>(3);
split(hsvImage, list);

Mat sChannelMat;

vector<Mat> sList = vector<Mat>{list[1]};

// sList.push_back(list[1]);
merge(sList, sChannelMat);

medianBlur(sChannelMat,sChannelMat,3);

// canny
Mat cannyMat;
Canny(sChannelMat, cannyMat, cannyMinThres, cannyMinThres*ratio, 3);

addWeighted(cannyMat,0.5, cannyGreyMat,0.5 ,0.0,cannyMat);
dilate(cannyMat, cannyMat,mask, Point(0.0,0.0), 5);

cout<<mRgbMat.cols<<","<<mRgbMat.rows<<"\n";

double width = imageSize.width;
double height = imageSize.height;

Point seedPoint = Point(p.x*(double(mRgbMat.cols)/width), p.y*(double(mRgbMat.rows)/height));

cout<<seedPoint.x<<","<<seedPoint.y<<"\n";

resize(cannyMat, cannyMat, Size(cannyMat.cols + 2.0, cannyMat.rows + 2.0));

medianBlur(mRgbMat,mRgbMat,15);

int floodFillFlag = 8;

int floodFillResult = floodFill(mRgbMat,cannyMat,seedPoint,chosenColor,0,Scalar(5.0, 5.0, 5.0),Scalar(5.0, 5.0, 5.0),floodFillFlag);

cout<<"paint_wall floodFillResult>>>>>>>>>>>>>>>"<<","<<floodFillResult<<"\n";
dilate(mRgbMat, mRgbMat, mask, Point(0.0,0.0), 5);

//got the hsv of the mask image
Mat rgbHsvImage;
cvtColor(mRgbMat,rgbHsvImage,COLOR_RGB2HSV);

vector<Mat> list1 = vector<Mat>(3);
split(rgbHsvImage, list1);

//merged the "v" of original image with mRgb mat
Mat result;

vector<Mat> newList = vector<Mat>();
newList.push_back(list1[0]);
newList.push_back(list1[1]);
newList.push_back(list[2]);
merge(newList, result);

// converted to rgb
cvtColor(result, result, COLOR_HSV2RGB);

addWeighted(result,0.7, img,0.3 ,0.0,result);

return result;

}

2

Any image editing shouldn’t care about kilobytes, only image size in pixels. You could probably find some pixel size where things start to go wrong.

To fix it, you need to find in your code any parameters are are image size dependent, and make them change according to image size. Or, you can resize the image to some size that works best.

3

crosspost: c++ - Unable to apply color or texture using openCV on iOS - Stack Overflow