图像融合算法

opencv3.0 photo 模块加入了seamless_cloning类。该类对应的论文是“Poisson Image Editing”

主要可以实现一下功能：

seamless clone：

纹理传输：

去除光噪：

等等。

本文主要以normal_clone为例， 从代码层面解释整个流程：

1.  在normal_clone 中需要准备三张图片，分别是source， mask， destination。 如最上面那张图，source就是熊，孩子那些要黏贴的图片，mask是这些前景的mask。 destination是背景，这里是水池。

2. 计算source和destination的x，y方向上的梯度

3. 计算lapx, lapy即对梯度再取梯度。得到lap

4. 取destination中非mask位置和source中mask位置lap，两者拼接得到最终lap

5. 用这个lap和原始图片，解决possion equation， 得到最终结果。（这部分不是很懂）

用到了Discrete sine transform， 

参考：http://www.mathworks.com/help/pde/ug/dst.html
   http://www.mathworks.com/help/pde/ug/fast-solution-of-poissons-equation.html

注释代码如下：（做了少量修改，与OpenCV不完全相同）

 #ifndef SEAMLESSCLONE_H_H
 #define SEAMLESSCLONE_H_H


 //#include "precomp.hpp"
 //#include "opencv2/photo.hpp"
 #include "opencv2/imgproc.hpp"
 #include "opencv2/core/core.hpp"
 #include
 #include
 #include
 #include "math.h"

 using namespace std;
 using namespace cv;

 namespace customCV {

     class Cloning
     {

     public:

         //output: 每个通道的合成结果数组
         //rbgx_channel, rgby_channel是gxx， gyy 分通道结果
         vector  rgb_channel, rgbx_channel, rgby_channel, output;

         //smask是source图片的mask， smask1是smask取反的结果
         //grx, gry 是dst图片的梯度。 grx32， gry32是smask1区域的梯度
         //sgx, sgy 是source图片的梯度。 srx32, sry32是smask区域的梯度
         Mat grx, gry, sgx, sgy, srx32, sry32, grx32, gry32, smask, smask1;
         void init_var(Mat &I, Mat &wmask);
         void initialization(Mat &I, Mat &mask, Mat &wmask);
         void scalar_product(Mat mat, float r, float g, float b);
         void array_product(Mat mat1, Mat mat2, Mat mat3);
         void poisson(Mat &I, Mat &gx, Mat &gy, Mat &sx, Mat &sy);
         void evaluate(Mat &I, Mat &wmask, Mat &cloned);
         void getGradientx(const Mat &img, Mat &gx);
         void getGradienty(const Mat &img, Mat &gy);
         void lapx(const Mat &img, Mat &gxx);
         void lapy(const Mat &img, Mat &gyy);
         void dst(double *mod_diff, double *sineTransform, int h, int w);
         void idst(double *mod_diff, double *sineTransform, int h, int w);
         void transpose(double *mat, double *mat_t, int h, int w);
         void solve(const Mat &img, double *mod_diff, Mat &result);
         void poisson_solver(const Mat &img, Mat &gxx, Mat &gyy, Mat &result);
         void normal_clone(Mat &I, Mat &mask, Mat &wmask, Mat &cloned, int num);
         void local_color_change(Mat &I, Mat &mask, Mat &wmask, Mat &cloned, float red_mul, float green_mul, float blue_mul);
         void illum_change(Mat &I, Mat &mask, Mat &wmask, Mat &cloned, float alpha, float beta);
         void texture_flatten(Mat &I, Mat &mask, Mat &wmask, double low_threshold, double high_threhold, int kernel_size, Mat &cloned);
     };




     void seamlessClone(InputArray _src, InputArray _dst, InputArray _mask, Point p, OutputArray _blend, int flags);
     void colorChange(InputArray _src, InputArray _mask, OutputArray _dst, float r, float g, float b);
     void illuminationChange(InputArray _src, InputArray _mask, OutputArray _dst, float a, float b);
     void textureFlattening(InputArray _src, InputArray _mask, OutputArray _dst, double low_threshold, double high_threshold, int kernel_size);

 }

 #endif

 //#include "precomp.hpp"
 //#include "opencv2/photo.hpp"
 #include
 #include

 #include "seamless_cloning.hpp"

 using namespace std;
 using namespace cv;

 namespace customCV {

     void Cloning::getGradientx(const Mat &img, Mat &gx)
     {
         Mat kernel = Mat::zeros(1, 3, CV_8S);
         kernel.at<char>(0, 2) = 1;
         kernel.at<char>(0, 1) = -1;
         filter2D(img, gx, CV_32F, kernel);
     }

     void Cloning::getGradienty(const Mat &img, Mat &gy)
     {
         Mat kernel = Mat::zeros(3, 1, CV_8S);
         kernel.at<char>(2, 0) = 1;
         kernel.at<char>(1, 0) = -1;
         filter2D(img, gy, CV_32F, kernel);
     }

     //img是原始图像水平方向上的梯度。本函数是对梯度再求梯度
     void Cloning::lapx(const Mat &img, Mat &gxx)
     {
         Mat kernel = Mat::zeros(1, 3, CV_8S);
         kernel.at<char>(0, 0) = -1;
         kernel.at<char>(0, 1) = 1;
         filter2D(img, gxx, CV_32F, kernel);
     }

     void Cloning::lapy(const Mat &img, Mat &gyy)
     {
         Mat kernel = Mat::zeros(3, 1, CV_8S);
         kernel.at<char>(0, 0) = -1;
         kernel.at<char>(1, 0) = 1;
         filter2D(img, gyy, CV_32F, kernel);
     }

     //离散正弦变换
     //参考：http://www.mathworks.com/help/pde/ug/dst.html
     //参考：http://www.mathworks.com/help/pde/ug/fast-solution-of-poissons-equation.html
     void Cloning::dst(double *mod_diff, double *sineTransform, int h, int w)
     {

         unsigned long int idx;

         Mat temp = Mat(2 * h + 2, 1, CV_32F);
         Mat res = Mat(h, 1, CV_32F);

         Mat planes[] = { Mat_<float>(temp), Mat::zeros(temp.size(), CV_32F) };

         Mat result;
         int p = 0;
         for (int i = 0; i < w; i++)
         {
             temp.at<float>(0, 0) = 0.0;

             for (int j = 0, r = 1; j < h; j++, r++)
             {
                 idx = j*w + i;
                 temp.at<float>(r, 0) = (float)mod_diff[idx];
             }

             temp.at<float>(h + 1, 0) = 0.0;

             for (int j = h - 1, r = h + 2; j >= 0; j--, r++)
             {
                 idx = j*w + i;
                 temp.at<float>(r, 0) = (float)(-1.0 * mod_diff[idx]);
             }

             merge(planes, 2, result);

             dft(result, result, 0, 0);

             Mat planes1[] = { Mat::zeros(result.size(), CV_32F), Mat::zeros(result.size(), CV_32F) };

             split(result, planes1);

             std::complex<double> two_i = std::sqrt(std::complex<double>(-1));

             double factor = -2 * imag(two_i);

             for (int c = 1, z = 0; c < h + 1; c++, z++)
             {
                 res.at<float>(z, 0) = (float)(planes1[1].at<float>(c, 0) / factor);
             }

             for (int q = 0, z = 0; q < h; q++, z++)
             {
                 idx = q*w + p;
                 sineTransform[idx] = res.at<float>(z, 0);
             }
             p++;
         }
     }

     void Cloning::idst(double *mod_diff, double *sineTransform, int h, int w)
     {
         int nn = h + 1;
         unsigned long int idx;
         dst(mod_diff, sineTransform, h, w);
         for (int i = 0; i < h; i++)
         for (int j = 0; j < w; j++)
         {
             idx = i*w + j;
             sineTransform[idx] = (double)(2 * sineTransform[idx]) / nn;
         }

     }

     void Cloning::transpose(double *mat, double *mat_t, int h, int w)
     {

         Mat tmp = Mat(h, w, CV_32FC1);
         unsigned long int idx;
         for (int i = 0; i < h; i++)
         {
             for (int j = 0; j < w; j++)
             {

                 idx = i*(w)+j;
                 tmp.at<float>(i, j) = (float)mat[idx];
             }
         }
         Mat tmp_t = tmp.t();

         for (int i = 0; i < tmp_t.size().height; i++)
         for (int j = 0; j < tmp_t.size().width; j++)
         {
             idx = i*tmp_t.size().width + j;
             mat_t[idx] = tmp_t.at<float>(i, j);
         }
     }

     void Cloning::solve(const Mat &img, double *mod_diff, Mat &result)
     {
         int w = img.size().width;
         int h = img.size().height;

         unsigned long int idx, idx1;

         double *sineTransform = new double[(h - 2)*(w - 2)];
         double *sineTransform_t = new double[(h - 2)*(w - 2)];
         double *denom = new double[(h - 2)*(w - 2)];
         double *invsineTransform = new double[(h - 2)*(w - 2)];
         double *invsineTransform_t = new double[(h - 2)*(w - 2)];
         double *img_d = new double[(h)*(w)];
         //结果存在img_d


         dst(mod_diff, sineTransform, h - 2, w - 2);
         transpose(sineTransform, sineTransform_t, h - 2, w - 2);


         dst(sineTransform_t, sineTransform, w - 2, h - 2);

         transpose(sineTransform, sineTransform_t, w - 2, h - 2);

         int cy = 1;

         for (int i = 0; i < w - 2; i++, cy++)
         {
             for (int j = 0, cx = 1; j < h - 2; j++, cx++)
             {
                 idx = j*(w - 2) + i;
                 denom[idx] = (float)2 * cos(CV_PI*cy / ((double)(w - 1))) - 2 + 2 * cos(CV_PI*cx / ((double)(h - 1))) - 2;

             }
         }

         for (idx = 0; idx < (unsigned)(w - 2)*(h - 2); idx++)
         {
             sineTransform_t[idx] = sineTransform_t[idx] / denom[idx];
         }

         idst(sineTransform_t, invsineTransform, h - 2, w - 2);

         transpose(invsineTransform, invsineTransform_t, h - 2, w - 2);

         idst(invsineTransform_t, invsineTransform, w - 2, h - 2);

         transpose(invsineTransform, invsineTransform_t, w - 2, h - 2);

         for (int i = 0; i < h; i++)
         {
             for (int j = 0; j < w; j++)
             {
                 idx = i*w + j;
                 img_d[idx] = (double)img.at(i, j);
             }
         }
         for (int i = 1; i < h - 1; i++)
         {
             for (int j = 1; j < w - 1; j++)
             {
                 idx = i*w + j;
                 img_d[idx] = 0.0;
             }
         }
         for (int i = 1, id1 = 0; i < h - 1; i++, id1++)
         {
             for (int j = 1, id2 = 0; j < w - 1; j++, id2++)
             {
                 idx = i*w + j;
                 idx1 = id1*(w - 2) + id2;
                 img_d[idx] = invsineTransform_t[idx1];
             }
         }


         for (int i = 0; i < h; i++)
         {
             for (int j = 0; j < w; j++)
             {
                 idx = i*w + j;
                 if (img_d[idx] < 0.0) {
                     result.at(i, j) = 0;
                 }
                 else if (img_d[idx] > 255.0)
                     result.at(i, j) = 255;
                 else {
                     result.at(i, j) = (uchar)img_d[idx];
                 }
             }
         }

         delete[] sineTransform;
         delete[] sineTransform_t;
         delete[] denom;
         delete[] invsineTransform;
         delete[] invsineTransform_t;
         delete[] img_d;
     }

     //由img和lap计算合成结果, 注意实际上lap有大量负数
     void Cloning::poisson_solver(const Mat &img, Mat &gxx, Mat &gyy, Mat &result)
     {

         int w = img.size().width;
         int h = img.size().height;

         unsigned long int idx;

         Mat lap = Mat(img.size(), CV_32FC1);

         lap = gxx + gyy;

         Mat bound = img.clone();

         //rectangle 外围保持原样，rect内部变为scalar
         rectangle(bound, Point(1, 1), Point(img.cols - 2, img.rows - 2), Scalar::all(0), -1);
         //rectangle(bound, Point(20, 20), Point(img.cols - 50, img.rows - 50), Scalar::all(0), -1);


         double *boundary_point = new double[h*w];

         Mat bound_map = cv::Mat(img.size(), CV_8UC1, cv::Scalar(0));

         for (int i = 1; i < h - 1; i++)
         for (int j = 1; j < w - 1; j++)
         {
             idx = i*w + j;
             boundary_point[idx] = -4 * (int)bound.at(i, j) + (int)bound.at(i, (j + 1)) + (int)bound.at(i, (j - 1))
                 + (int)bound.at(i - 1, j) + (int)bound.at(i + 1, j);
             bound_map.at(i, j) = boundary_point[idx];
         }



         Mat diff = Mat(h, w, CV_32FC1);
         for (int i = 0; i < h; i++)
         {
             for (int j = 0; j < w; j++)
             {
                 idx = i*w + j;
                 diff.at<float>(i, j) = (float)(lap.at<float>(i, j) - boundary_point[idx]);
             }
         }

         //diff和lap几乎没什么区别

         double *mod_diff = new double[(h - 2)*(w - 2)];
         for (int i = 0; i < h - 2; i++)
         {
             for (int j = 0; j < w - 2; j++)
             {
                 idx = i*(w - 2) + j;
                 mod_diff[idx] = diff.at<float>(i + 1, j + 1);

             }
         }
         ///////////////////////////////////////////////////// Find DST  /////////////////////////////////////////////////////
         solve(img, mod_diff, result);

         delete[] mod_diff;
         delete[] boundary_point;
     }

     void Cloning::init_var(Mat &I, Mat &wmask)
     {
         grx = Mat(I.size(), CV_32FC3);
         gry = Mat(I.size(), CV_32FC3);
         sgx = Mat(I.size(), CV_32FC3);
         sgy = Mat(I.size(), CV_32FC3);

         split(I, rgb_channel);


         smask = Mat(wmask.size(), CV_32FC1);
         srx32 = Mat(I.size(), CV_32FC3);
         sry32 = Mat(I.size(), CV_32FC3);
         smask1 = Mat(wmask.size(), CV_32FC1);
         grx32 = Mat(I.size(), CV_32FC3);
         gry32 = Mat(I.size(), CV_32FC3);
     }

     void Cloning::initialization(Mat &I, Mat &mask, Mat &wmask)
     {
         //初始化各个mat
         init_var(I, wmask);

         //grx, gry 分别表示dest的x，y方向的梯度
         getGradientx(I, grx);
         getGradienty(I, gry);

         //sgx, sgy 分别表示在mask区域内的source图片在x，y方向的梯度
         getGradientx(mask, sgx);
         getGradienty(mask, sgy);

         Mat Kernel(Size(3, 3), CV_8UC1);
         Kernel.setTo(Scalar(1));
         //腐蚀
         erode(wmask, wmask, Kernel, Point(-1, -1), 3);

         wmask.convertTo(smask, CV_32FC1, 1.0 / 255.0);
         I.convertTo(srx32, CV_32FC3, 1.0 / 255.0);
         I.convertTo(sry32, CV_32FC3, 1.0 / 255.0);
     }

     void Cloning::scalar_product(Mat mat, float r, float g, float b)
     {
         vector  channels;
         split(mat, channels);
         multiply(channels[2], r, channels[2]);
         multiply(channels[1], g, channels[1]);
         multiply(channels[0], b, channels[0]);
         merge(channels, mat);
     }

     //mat1 = mat3.mul(mat2(:))  mat3为单通道，一般为mask
     void Cloning::array_product(Mat mat1, Mat mat2, Mat mat3)
     {
         vector  channels_temp1;
         vector  channels_temp2;
         split(mat1, channels_temp1);
         split(mat2, channels_temp2);
         multiply(channels_temp2[2], mat3, channels_temp1[2]);
         multiply(channels_temp2[1], mat3, channels_temp1[1]);
         multiply(channels_temp2[0], mat3, channels_temp1[0]);
         merge(channels_temp1, mat1);
     }

     void Cloning::poisson(Mat &I, Mat &gx, Mat &gy, Mat &sx, Mat &sy)
     {
         //fx, fy是两者组合的梯度
         Mat fx = Mat(I.size(), CV_32FC3);
         Mat fy = Mat(I.size(), CV_32FC3);

         fx = gx + sx;
         fy = gy + sy;


         Mat gxx = Mat(I.size(), CV_32FC3);
         Mat gyy = Mat(I.size(), CV_32FC3);

         //gxx, gyy 是在x，y方向的laplacian算子
         lapx(fx, gxx);
         lapy(fy, gyy);


         split(gxx, rgbx_channel);
         split(gyy, rgby_channel);

         split(I, output);


         poisson_solver(rgb_channel[2], rgbx_channel[2], rgby_channel[2], output[2]);
         poisson_solver(rgb_channel[1], rgbx_channel[1], rgby_channel[1], output[1]);
         poisson_solver(rgb_channel[0], rgbx_channel[0], rgby_channel[0], output[0]);
     }

     void Cloning::evaluate(Mat &I, Mat &wmask, Mat &cloned)
     {
         //mask取反
         bitwise_not(wmask, wmask);

         wmask.convertTo(smask1, CV_32FC1, 1.0 / 255.0);
         I.convertTo(grx32, CV_32FC3, 1.0 / 255.0);
         I.convertTo(gry32, CV_32FC3, 1.0 / 255.0);

         array_product(grx32, grx, smask1);
         array_product(gry32, gry, smask1);

         poisson(I, grx32, gry32, srx32, sry32);

         merge(output, cloned);
     }

     void Cloning::normal_clone(Mat &I, Mat &mask, Mat &wmask, Mat &cloned, int num)
     {
         int w = I.size().width;
         int h = I.size().height;
         int channel = I.channels();

         //初始化各个存储参数的mat，并计算原图于目标图的x，y方向梯度，对mask腐蚀
         initialization(I, mask, wmask);

         if (num == 1) //NORMAL_CLONE
         {
             //srx32, sry32是sgx，sgy的mask区域
             array_product(srx32, sgx, smask);
             array_product(sry32, sgy, smask);
         }
         else if (num == 2) //MIXED_CLONE
         {

             for (int i = 0; i < h; i++)
             {
                 for (int j = 0; j < w; j++)
                 {
                     for (int c = 0; c
                     {
                         if (abs(sgx.at<float>(i, j*channel + c) - sgy.at<float>(i, j*channel + c)) >
                             abs(grx.at<float>(i, j*channel + c) - gry.at<float>(i, j*channel + c)))
                         {

                             srx32.at<float>(i, j*channel + c) = sgx.at<float>(i, j*channel + c)
                                 * smask.at<float>(i, j);
                             sry32.at<float>(i, j*channel + c) = sgy.at<float>(i, j*channel + c)
                                 * smask.at<float>(i, j);
                         }
                         else
                         {
                             srx32.at<float>(i, j*channel + c) = grx.at<float>(i, j*channel + c)
                                 * smask.at<float>(i, j);
                             sry32.at<float>(i, j*channel + c) = gry.at<float>(i, j*channel + c)
                                 * smask.at<float>(i, j);
                         }
                     }
                 }
             }

         }
         else if (num == 3) //FEATURE_EXCHANGE
         {
             Mat gray = Mat(mask.size(), CV_8UC1);
             Mat gray8 = Mat(mask.size(), CV_8UC3);
             cvtColor(mask, gray, COLOR_BGR2GRAY);
             vector  temp;
             split(I, temp);
             gray.copyTo(temp[2]);
             gray.copyTo(temp[1]);
             gray.copyTo(temp[0]);

             merge(temp, gray8);

             getGradientx(gray8, sgx);
             getGradienty(gray8, sgy);

             array_product(srx32, sgx, smask);
             array_product(sry32, sgy, smask);

         }

         evaluate(I, wmask, cloned);
     }

     void Cloning::local_color_change(Mat &I, Mat &mask, Mat &wmask, Mat &cloned, float red_mul = 1.0,
         float green_mul = 1.0, float blue_mul = 1.0)
     {
         initialization(I, mask, wmask);

         array_product(srx32, sgx, smask);
         array_product(sry32, sgy, smask);
         scalar_product(srx32, red_mul, green_mul, blue_mul);
         scalar_product(sry32, red_mul, green_mul, blue_mul);

         evaluate(I, wmask, cloned);
     }

     void Cloning::illum_change(Mat &I, Mat &mask, Mat &wmask, Mat &cloned, float alpha, float beta)
     {
         initialization(I, mask, wmask);

         array_product(srx32, sgx, smask);
         array_product(sry32, sgy, smask);

         Mat mag = Mat(I.size(), CV_32FC3);
         magnitude(srx32, sry32, mag);

         //opencv3.0 alpha中有bug，需要加入一下代码才不能得到正确结果。已经提交bug
         for (int i = 0; i < mag.cols; i++)
         {
             for (int j = 0; j < mag.rows; j++)
             {
                 if (mag.at(j, i)[0] == 0)
                     mag.at(j, i)[0] = 1e-8;

                 if (mag.at(j, i)[1] == 0)
                     mag.at(j, i)[1] = 1e-8;

                 if (mag.at(j, i)[2] == 0)
                     mag.at(j, i)[2] = 1e-8;
             }
         }

         Mat multX, multY, multx_temp, multy_temp;

         multiply(srx32, pow(alpha, beta), multX);
         pow(mag, -1 * beta, multx_temp);
         multiply(multX, multx_temp, srx32);

         multiply(sry32, pow(alpha, beta), multY);
         pow(mag, -1 * beta, multy_temp);
         multiply(multY, multy_temp, sry32);

         Mat zeroMask = (srx32 != 0);

         srx32.copyTo(srx32, zeroMask);
         sry32.copyTo(sry32, zeroMask);

         evaluate(I, wmask, cloned);
     }

     void Cloning::texture_flatten(Mat &I, Mat &mask, Mat &wmask, double low_threshold,
         double high_threshold, int kernel_size, Mat &cloned)
     {
         initialization(I, mask, wmask);

         Mat out = Mat(mask.size(), CV_8UC1);
         Canny(mask, out, low_threshold, high_threshold, kernel_size);

         Mat zeros(sgx.size(), CV_32FC3);
         zeros.setTo(0);
         Mat zerosMask = (out != 255);
         zeros.copyTo(sgx, zerosMask);
         zeros.copyTo(sgy, zerosMask);

         array_product(srx32, sgx, smask);
         array_product(sry32, sgy, smask);

         evaluate(I, wmask, cloned);
     }



     void seamlessClone(InputArray _src, InputArray _dst, InputArray _mask, Point p, OutputArray _blend, int flags)
     {
         Mat src = _src.getMat();
         Mat dest = _dst.getMat();
         Mat mask = _mask.getMat();
         _blend.create(dest.size(), CV_8UC3);
         Mat blend = _blend.getMat();

         int minx = INT_MAX, miny = INT_MAX, maxx = INT_MIN, maxy = INT_MIN;
         int h = mask.size().height;
         int w = mask.size().width;

         Mat gray = Mat(mask.size(), CV_8UC1);
         Mat dst_mask = Mat::zeros(dest.size(), CV_8UC1);
         Mat cs_mask = Mat::zeros(src.size(), CV_8UC3);
         Mat cd_mask = Mat::zeros(dest.size(), CV_8UC3);

         if (mask.channels() == 3)
             cvtColor(mask, gray, COLOR_BGR2GRAY);
         else
             gray = mask;

         for (int i = 0; i < h; i++)
         {
             for (int j = 0; j < w; j++)
             {
                 if (gray.at(i, j) == 255)
                 {
                     minx = std::min(minx, i);
                     maxx = std::max(maxx, i);
                     miny = std::min(miny, j);
                     maxy = std::max(maxy, j);
                 }
             }
         }

         int lenx = maxx - minx;
         int leny = maxy - miny;

         int minxd = p.y - lenx / 2;
         int maxxd = p.y + lenx / 2;
         int minyd = p.x - leny / 2;
         int maxyd = p.x + leny / 2;

         CV_Assert(minxd >= 0 && minyd >= 0 && maxxd <= dest.rows && maxyd <= dest.cols);

         Rect roi_d(minyd, minxd, leny, lenx);
         Rect roi_s(miny, minx, leny, lenx);

         Mat destinationROI = dst_mask(roi_d);
         Mat sourceROI = cs_mask(roi_s);

         gray(roi_s).copyTo(destinationROI);
         src(roi_s).copyTo(sourceROI, gray(roi_s));

         destinationROI = cd_mask(roi_d);
         cs_mask(roi_s).copyTo(destinationROI);

         Cloning obj;
         obj.normal_clone(dest, cd_mask, dst_mask, blend, flags);

     }

     void colorChange(InputArray _src, InputArray _mask, OutputArray _dst, float r, float g, float b)
     {
         Mat src = _src.getMat();
         Mat mask = _mask.getMat();
         _dst.create(src.size(), src.type());
         Mat blend = _dst.getMat();

         float red = r;
         float green = g;
         float blue = b;

         Mat gray = Mat::zeros(mask.size(), CV_8UC1);

         if (mask.channels() == 3)
             cvtColor(mask, gray, COLOR_BGR2GRAY);
         else
             gray = mask;

         Mat cs_mask = Mat::zeros(src.size(), CV_8UC3);

         src.copyTo(cs_mask, gray);

         Cloning obj;
         obj.local_color_change(src, cs_mask, gray, blend, red, green, blue);
     }

     void illuminationChange(InputArray _src, InputArray _mask, OutputArray _dst, float a, float b)
     {

         Mat src = _src.getMat();
         Mat mask = _mask.getMat();
         _dst.create(src.size(), src.type());
         Mat blend = _dst.getMat();
         float alpha = a;
         float beta = b;

         Mat gray = Mat::zeros(mask.size(), CV_8UC1);

         if (mask.channels() == 3)
             cvtColor(mask, gray, COLOR_BGR2GRAY);
         else
             gray = mask;

         Mat cs_mask = Mat::zeros(src.size(), CV_8UC3);

         src.copyTo(cs_mask, gray);

         Cloning obj;
         obj.illum_change(src, cs_mask, gray, blend, alpha, beta);
     }

     void textureFlattening(InputArray _src, InputArray _mask, OutputArray _dst,
         double low_threshold, double high_threshold, int kernel_size)
     {

         Mat src = _src.getMat();
         Mat mask = _mask.getMat();
         _dst.create(src.size(), src.type());
         Mat blend = _dst.getMat();

         Mat gray = Mat::zeros(mask.size(), CV_8UC1);

         if (mask.channels() == 3)
             cvtColor(mask, gray, COLOR_BGR2GRAY);
         else
             gray = mask;

         Mat cs_mask = Mat::zeros(src.size(), CV_8UC3);

         src.copyTo(cs_mask, gray);

         Cloning obj;
         obj.texture_flatten(src, cs_mask, gray, low_threshold, high_threshold, kernel_size, blend);
     }

 }