Question

我正在尝试实现用于显着性检测的光谱残差方法，如本文所述： http://www.klab.caltech.edu/~xhou/papers/cvpr07.pdf

Matlab代码中有一个参考实现，取自他们的网站： http://www.klab.caltech.edu/~xhou/projects/spectralResidual/spectralresidual.html

clear
clc
%% Read image from file
inImg = im2double(rgb2gray(imread('yourImage.jpg')));
inImg = imresize(inImg, 64/size(inImg, 2));
%% Spectral Residual
myFFT = fft2(inImg);
myLogAmplitude = log(abs(myFFT));
myPhase = angle(myFFT);
mySpectralResidual = myLogAmplitude - imfilter(myLogAmplitude, fspecial('average', 3),'replicate');
saliencyMap = abs(ifft2(exp(mySpectralResidual + i*myPhase))).^2;
%% After Effect
saliencyMap = mat2gray(imfilter(saliencyMap, fspecial('gaussian', [10, 10], 2.5)));
imshow(saliencyMap);

我试图用CImg将其翻译成C ++。我失败的地方就在这里：

myPhase = angle(myFFT);

在这里

saliencyMap = abs(ifft2(exp(mySpectralResidual + i*myPhase))).^2;

这是我的代码：

#include <CImg.h>
#include <iostream>
using namespace cimg_library;

int main() {

  CImg<unsigned char> image("img2.jpg");

  CImg<float> mask(3,3,1,1,1.0/9.0);

  image.resize(64,64);

  CImgList<float> myFFT = image.get_FFT();

  const CImg<float> MyLogAmplitude = ((myFFT[0].get_pow(2) +  myFFT[1].get_pow(2)).get_sqrt()).get_log(); //Magnitude

  const CImg<float> MyPhase = myFFT[0].get_atan2(myFFT[1]);

  const CImg<float> A = MyLogAmplitude.get_convolve(mask);

  const CImg<float> MySpectralResidual = MyLogAmplitude-A;

  CImgList<float> tmp = CImgList<float>(MyResidual.get_exp(),MyPhase);

  CImgList<float> MySaliencyMap = tmp.get_FFT(true);

  CImgDisplay  draw_disp0(MySaliencyMap,"Image");


  while (!draw_disp0.is_closed()) {

    draw_disp0.wait();

  }
  return 0;
}

有人看到过一个明显的错误吗？

Answer 1

我想我可以在你的代码中看到两个错误：

首先，对MyPhase的atan2（）调用反转了参数。应该写成

const CImg MyPhase = myFFT [1] .get_atan2（myFFT [0]）;

（但这可能不是什么问题）。

第二，更严重的是，你正在对编码为（幅度，相位）的一对复数值进行逆FFT，这不是CImg所期望的，因为FFT（）函数假设你输入了一个（真实的，想象的）一对图像。这可能会对结果产生巨大影响。

Answer 2

其实我遇到了同样的问题。这是解决问题的代码。我编辑了一些在对象突出部分周围创建一个矩形。这段代码适合我。

#include "highgui.h"
#include "opencv2/imgproc/imgproc.hpp"
#include "cv.h"
#include <stdlib.h>
#include <stdio.h>
#include <string>
#include <iostream>



using namespace cv;
using namespace std;

// function Fourier transform 
void fft2(IplImage *src, IplImage *dst);

int main()
{

           string imagePath = "inputgambar/34.jpg";
              //string imageSave = "saliency/42.jpg";
    //string imageRectangular = "rectangular/42.jpg";

    IplImage *ImageAsli, *ImageSaliency, *src, *ImageRe, *ImageIm, *Fourier, *Inverse, *LogAmplitude, *Sine, *Cosine;
    IplImage *Saliency, *Residual;
    IplImage *tmp1, *tmp2, *tmp3;
    Mat gambarSave, threshold_output;
    vector<vector<Point> > contours;
    vector<Vec4i> hierarchy;
    double minNum = 0, maxNum = 0, scale, shift, rata2, nilaiThreshold, Lebar, gantiPixel;


    // load image Asli
    ImageAsli = cvLoadImage(imagePath.c_str());
    cvNamedWindow("ImageAsli", CV_WINDOW_NORMAL);
    cvShowImage("ImageAsli", ImageAsli);
    cvMoveWindow("ImageAsli",0,100);

    // Load image, jadikan single channel/gray
    //inputImage = cvLoadImage(imagePath.c_str());
    src = cvLoadImage(imagePath.c_str(),0);
    Lebar = src->width;
    gantiPixel = 64/Lebar; 

    // Fourier , punya 2 channel, Real dan Imajiner
    Fourier = cvCreateImage(cvGetSize(src), IPL_DEPTH_64F, 2);
    Inverse = cvCreateImage(cvGetSize(src), IPL_DEPTH_64F, 2);
    // Real , Imajiner spektrum
    ImageRe = cvCreateImage (cvGetSize (src), IPL_DEPTH_64F, 1);
    ImageIm = cvCreateImage (cvGetSize (src), IPL_DEPTH_64F, 1);
    // log amplitude 
    LogAmplitude = cvCreateImage (cvGetSize (src), IPL_DEPTH_64F, 1);
    // Sinus, Cosinus spektrum
    Sine = cvCreateImage (cvGetSize (src), IPL_DEPTH_64F, 1);
    Cosine = cvCreateImage(cvGetSize(src), IPL_DEPTH_64F, 1);

    // spectral residual
    Residual = cvCreateImage (cvGetSize (src), IPL_DEPTH_64F, 1);
    // Saliency
    Saliency = cvCreateImage (cvGetSize (src), src-> depth, src-> nChannels);

    // Temporary space
    tmp1 = cvCreateImage(cvGetSize(src), IPL_DEPTH_64F, 1);
    tmp2 = cvCreateImage(cvGetSize(src), IPL_DEPTH_64F, 1);
    tmp3 = cvCreateImage(cvGetSize(src), IPL_DEPTH_64F, 1);

    // 
    scale = 1.0/255.0;
    cvConvertScale (src, tmp1, 1, 0);

    //
    fft2 (tmp1, Fourier);

    // Real dan Imajiner ditaruh di ImageRe ImageIm
    cvSplit (Fourier, ImageRe, ImageIm, 0, 0);

    // Magnitude/Amplitudo Fourier di tmp3
    cvPow( ImageRe, tmp1, 2.0);
    cvPow( ImageIm, tmp2, 2.0);
    cvAdd( tmp1, tmp2, tmp3);
    cvPow( tmp3, tmp3, 0.5 );

    // logAmplitude , sin, cosin 
    cvLog (tmp3, LogAmplitude);
    cvDiv (ImageIm, tmp3, Sine);
    cvDiv (ImageRe, tmp3, Cosine);

    // smoothing (1/(3×3)) * ones(3), mean filter pada logAmplitude ditempatkan pada tmp3
    cvSmooth (LogAmplitude, tmp3, CV_BLUR, 3, 3);

    // Spectral Residual = LogAmp-tmp3
    cvSub (LogAmplitude, tmp3, Residual);

    /************************************************************************ /
   inverse Fourier Transform --> exp (Residual + i * Phase)

    Euler's formula:
    exp(r + i * T) = exp(r) * (cos(T) + i * sin(T)) = exp(r) * cos(T) + i * exp(r) * sin(T)

    Sin (T) = ImageIm / LogAmplitude;  cos(T) = ImageRe / LogAmplitude;
    /************************************************************************/
    cvExp(Residual, Residual);
    cvMul(Residual, Cosine, tmp1);
    cvMul(Residual, Sine, tmp2);


    // Merging Residual, Saliency 1 channel => Fourier 2 channel
    cvMerge (tmp1, tmp2, 0, 0, Fourier);

    // Inverse Fourier transform
    cvDFT (Fourier, Inverse, CV_DXT_INV_SCALE);

    cvSplit (Inverse, tmp1, tmp2, 0,0);

    // tmp3 = kuadrat akar tmp1 tmp2
    cvPow (tmp1, tmp1, 2);
    cvPow (tmp2, tmp2, 2);
    cvAdd (tmp1, tmp2, tmp3);

    // Gaussian filter 7x7 kernel
    cvSmooth (tmp3, tmp3, CV_GAUSSIAN, 7, 7);
    //CoreCVminmaxloc
    cvMinMaxLoc (tmp3, & minNum, & maxNum, NULL, NULL);

    scale = 255 / (maxNum - minNum);
    shift =-minNum * scale;

    // End of Saliency
    cvConvertScale(tmp3, Saliency, scale, shift);

    //deteksi proto objek
    CvScalar rataan = cvAvg(Saliency);
    nilaiThreshold = 3* (rataan .val[0]);
    //cout << nilaiThreshold ;
    gambarSave = Mat(Saliency);
    //imwrite(imageSave.c_str(), gambarSave);
    //resize(gambarSave, gambarSave, Size(), gantiPixel, gantiPixel, CV_INTER_AREA);
    //ImageSaliency = cvCreateImage(cvSize(Saliency-> width * gantiPixel, Saliency-> height *gantiPixel), Saliency -> depth, Saliency -> nChannels);
    //cvResize(Saliency, ImageSaliency, CV_INTER_AREA);
    cvNamedWindow("Saliency", CV_WINDOW_NORMAL);
    cvShowImage("Saliency", Saliency);
    cvMoveWindow("Saliency",0,500);

  /// Detect edges using Threshold
  threshold( gambarSave, threshold_output, nilaiThreshold, 255, THRESH_BINARY );
  /// Find contours
  findContours( threshold_output, contours, hierarchy, CV_RETR_EXTERNAL, CV_CHAIN_APPROX_SIMPLE, Point(0, 0) );

  /// Find the rotated rectangles 
  vector<RotatedRect> minRect( contours.size() );

  for( int i = 0; i < contours.size(); i++ )
    { minRect[i] = minAreaRect( Mat(contours[i]) );
    }
  /// Draw rotated rects 
  for( int i = 0; i< contours.size(); i++ )
     {
       // rotated rectangle
       Point2f rect_points[4]; minRect[i].points( rect_points );
       for( int j = 0; j < 4; j++ )
          line( gambarSave, rect_points[j], rect_points[(j+1)%4], Scalar(100), 2, 8 );
     }

  //imwrite(imageRectangular.c_str(), gambarSave);
  /// Show in a window
  namedWindow( "Rectangular", CV_WINDOW_AUTOSIZE );
  imshow( "Rectangular", gambarSave );
  cvMoveWindow("Rectangular",480,100);


    cvWaitKey(0);

    //Release images
    cvReleaseImage(&src);
    cvReleaseImage(&ImageIm);
    cvReleaseImage(&ImageRe);
    cvReleaseImage(&Fourier);
    cvReleaseImage(&Inverse);
    cvReleaseImage(&LogAmplitude);
    cvReleaseImage(&Sine);
    cvReleaseImage(&Cosine);
    cvReleaseImage(&Saliency);
    cvReleaseImage(&Residual);
    cvReleaseImage(&tmp1);
    cvReleaseImage(&tmp2);
    cvReleaseImage(&tmp3);
    cvReleaseImage(&ImageAsli);

    cvDestroyAllWindows();

    return 0;
}


//Fourier transform
void fft2(IplImage *src, IplImage *dst)
{   
    IplImage *image_Re = 0, *image_Im = 0, *Fourier = 0;

    //1 channel ImageRe, ImageIm
    image_Re = cvCreateImage(cvGetSize(src), IPL_DEPTH_64F, 1);  
    image_Im = cvCreateImage(cvGetSize(src), IPL_DEPTH_64F, 1);  

    //2 channels (image_Re, image_Im)
    Fourier = cvCreateImage(cvGetSize(src), IPL_DEPTH_64F, 2);

    /************************************************* ***********************/
    // isi nilai image_Re 
    cvConvertScale(src, image_Re, 1, 0);
    // nilai initial Imajiner di Set 0
    cvZero(image_Im);
    // Join real and imaginary parts and stock them in Fourier image
    cvMerge(image_Re, image_Im, 0, 0, Fourier);
    // forward Fourier transform
    cvDFT(Fourier, dst, CV_DXT_FORWARD);
    cvReleaseImage(&image_Re);
    cvReleaseImage(&image_Im);
    cvReleaseImage(&Fourier);
}

This is the program output http://i60.tinypic.com/5xvmhi.png

用CImg进行C ++中的谱残余显着性检测

2 个答案: