OpenCV  3.3.0
Open Source Computer Vision
falsecolor.cpp

An example using applyColorMap function

#include <opencv2/opencv.hpp>
using namespace cv;
using namespace std;
enum MyShape{MyCIRCLE=0,MyRECTANGLE,MyELLIPSE};
struct ParamColorMar {
int iColormap;
Mat img;
};
Ptr<Mat> lutRND;
String winName="False color";
static void TrackColorMap(int x, void *r)
{
ParamColorMar *p = (ParamColorMar*)r;
Mat dst;
p->iColormap= x;
if (x == cv::COLORMAP_PARULA + 1)
{
if (!lutRND)
{
RNG ra;
Mat *palette = new Mat(256, 1, CV_8UC3);
ra.fill(*palette, RNG::UNIFORM, 0, 256);
lutRND = Ptr<Mat>(palette);
}
applyColorMap(p->img, dst, *lutRND.get());
}
else
applyColorMap(p->img,dst,p->iColormap);
String colorMapName;
switch (p->iColormap) {
colorMapName = "Colormap : Autumn";
break;
colorMapName = "Colormap : Bone";
break;
case COLORMAP_JET :
colorMapName = "Colormap : Jet";
break;
colorMapName = "Colormap : Winter";
break;
colorMapName = "Colormap : Rainbow";
break;
colorMapName = "Colormap : Ocean";
break;
colorMapName = "Colormap : Summer";
break;
colorMapName = "Colormap : Spring";
break;
colorMapName = "Colormap : Cool";
break;
case COLORMAP_HSV :
colorMapName = "Colormap : HSV";
break;
colorMapName = "Colormap : Pink";
break;
case COLORMAP_HOT :
colorMapName = "Colormap : Hot";
break;
colorMapName = "Colormap : Parula";
break;
default:
colorMapName = "User colormap : random";
break;
}
putText(dst, colorMapName, Point(10, 20), cv::FONT_HERSHEY_SIMPLEX, 1, Scalar(255, 255, 255));
imshow(winName, dst);
}
static Mat DrawMyImage(int thickness,int nbShape)
{
Mat img=Mat::zeros(500,256*thickness+100,CV_8UC1);
int offsetx = 50, offsety = 25;
int lineLenght = 50;
for (int i=0;i<256;i++)
line(img,Point(thickness*i+ offsetx, offsety),Point(thickness*i+ offsetx, offsety+ lineLenght),Scalar(i), thickness);
RNG r;
Point center;
int radius;
int width,height;
int angle;
Rect rc;
for (int i=1;i<=nbShape;i++)
{
int typeShape = r.uniform(MyCIRCLE, MyELLIPSE+1);
switch (typeShape) {
case MyCIRCLE:
center = Point(r.uniform(offsetx,img.cols- offsetx), r.uniform(offsety + lineLenght, img.rows - offsety));
radius = r.uniform(1, min(offsetx, offsety));
circle(img,center,radius,Scalar(i),-1);
break;
case MyRECTANGLE:
center = Point(r.uniform(offsetx, img.cols - offsetx), r.uniform(offsety + lineLenght, img.rows - offsety));
width = r.uniform(1, min(offsetx, offsety));
height = r.uniform(1, min(offsetx, offsety));
rc = Rect(center-Point(width ,height )/2, center + Point(width , height )/2);
rectangle(img,rc, Scalar(i), -1);
break;
case MyELLIPSE:
center = Point(r.uniform(offsetx, img.cols - offsetx), r.uniform(offsety + lineLenght, img.rows - offsety));
width = r.uniform(1, min(offsetx, offsety));
height = r.uniform(1, min(offsetx, offsety));
angle = r.uniform(0, 180);
ellipse(img, center,Size(width/2,height/2),angle,0,360, Scalar(i), -1);
break;
}
}
return img;
}
int main(int argc, char** argv)
{
ParamColorMar p;
Mat img;
if (argc > 1)
img = imread(argv[1], 0);
else
img = DrawMyImage(2,256);
p.img=img;
p.iColormap=0;
imshow("Gray image",img);
namedWindow(winName);
createTrackbar("colormap", winName,&p.iColormap,1,TrackColorMap,(void*)&p);
setTrackbarMin("colormap", winName, cv::COLORMAP_AUTUMN);
setTrackbarMax("colormap", winName, cv::COLORMAP_PARULA+1);
setTrackbarPos("colormap", winName, -1);
TrackColorMap(0,(void*)&p);
waitKey(0);
return 0;
}