Zależności edytuj

wymagane edytuj

GCC 4.4.x or later
CMake 2.8.7 or higher
Git
GTK+ ( 2.x or higher, including headers =libgtk2.0-dev )
pkg-config
Python 2.6 or later and Numpy 1.5 or later with developer packages (python-dev, python-numpy)
ffmpeg or libav development packages: libavcodec-dev, libavformat-dev, libswscale-dev

opcjonalne edytuj

libtbb2 libtbb-dev
libdc1394 2.x
libjpeg-dev, libpng-dev, libtiff-dev, libjasper-dev, libdc1394-22-dev
CUDA Toolkit 6.5 or higher

pliki edytuj

Lokalizacja edytuj

Szukamy pliku opencv.pc:

 pkg-config --cflags opencv

typowy wynik w Linuksie :

 -I/usr/include/opencv

apt-file search opencv.pc

Lub flagi:

pkg-config --cflags -- opencv4

Wynik:

-I/usr/local/include/opencv4

Wersje edytuj

biblioteki edytuj

Sprawdzamy jaką mamy wersję:^[1]

 pkg-config --modversion opencv

lub

 dpkg -l | grep libopencv

językowe edytuj

C++
python
java
c : "C API was present in OpenCV 1.x. Now it is supported for backward compatibility only. It is deprecated and may be removed in the future."^[2]

Instalacja edytuj

linuxize : how-to-install-opencv-on-ubuntu-20-04
sudo apt install libopencv-dev python3-opencv

git edytuj

Ściągnij kod: ^[3]

 git clone https://github.com/opencv/opencv.git

wersja edytuj

Sprawdzamy wersję ^[4]

  pkg-config --modversion opencv

Katalog :^[5]

 pkg-config --cflags opencv

przykładowy wynik :

 -I/usr/include/opencv

inny sposób :

  pkg-config --libs opencv

Wynik :

/usr/lib/x86_64-linux-gnu/libopencv_calib3d.so -lopencv_calib3d /usr/lib/x86_64-linux-gnu/libopencv_contrib.so -lopencv_contrib /usr/lib/x86_64-linux-gnu/libopencv_core.so -lopencv_core /usr/lib/x86_64-linux-gnu/libopencv_features2d.so -lopencv_features2d /usr/lib/x86_64-linux-gnu/libopencv_flann.so -lopencv_flann /usr/lib/x86_64-linux-gnu/libopencv_gpu.so -lopencv_gpu /usr/lib/x86_64-linux-gnu/libopencv_highgui.so -lopencv_highgui /usr/lib/x86_64-linux-gnu/libopencv_imgproc.so -lopencv_imgproc /usr/lib/x86_64-linux-gnu/libopencv_legacy.so -lopencv_legacy /usr/lib/x86_64-linux-gnu/libopencv_ml.so -lopencv_ml /usr/lib/x86_64-linux-gnu/libopencv_objdetect.so -lopencv_objdetect /usr/lib/x86_64-linux-gnu/libopencv_ocl.so -lopencv_ocl /usr/lib/x86_64-linux-gnu/libopencv_photo.so -lopencv_photo /usr/lib/x86_64-linux-gnu/libopencv_stitching.so -lopencv_stitching /usr/lib/x86_64-linux-gnu/libopencv_superres.so -lopencv_superres /usr/lib/x86_64-linux-gnu/libopencv_ts.so -lopencv_ts /usr/lib/x86_64-linux-gnu/libopencv_video.so -lopencv_video /usr/lib/x86_64-linux-gnu/libopencv_videostab.so -lopencv_videostab

sprawdzanie edytuj

 apt-file search opencv.pc

Funkcje edytuj

convexHull
isContourConvex
convexityDefects
Extreme Points means topmost, bottommost, rightmost and leftmost points of the object.

moduły edytuj

highgui^[6]^[7]
podstawowe struktury w C ( ang. basic c structures)

Przykłady edytuj

c edytuj

 "plain C API was discontinued somewhere before version 3.x !"^[8]

 #include "cv.h"
 #include "highgui.h"

  gcc opencv.c -o opencv `pkg-config --libs --cflags opencv` -ldl -lm

wersja edytuj

/*
 http://stackoverflow.com/questions/2422514/how-to-check-for-opencv-on-ubuntu-9-10/12449594#12449594
 g++ `pkg-config --cflags opencv` c.c `pkg-config --libs opencv` 
 gcc c.c  `pkg-config --cflags --libs opencv` 
*/

#include <stdio.h>
#include <cv.h>

int main(void)
{
    printf("%s\r\n", CV_VERSION);
    printf("%u.%u.%u\r\n", CV_MAJOR_VERSION, CV_MINOR_VERSION, CV_SUBMINOR_VERSION);
}

Przykładowy wynik:

2.4.9.1
2.4.9

gui i otwieranie obrazów edytuj

/*
http://www.cs.iit.edu/~agam/cs512/lect-notes/opencv-intro/

gcc h.c  `pkg-config --cflags --libs opencv`


OpenCV uses BGR as its default colour order for images,




*/
////////////////////////////////////////////////////////////////////////
//
// h.c
//
// This is a simple, introductory OpenCV program. The program reads an
// image from a file, inverts it, and displays the result. 
//
////////////////////////////////////////////////////////////////////////
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <cv.h>
#include <highgui.h> // // highgui_c.h


int main(int argc, char *argv[])
{
  IplImage* img = 0; 
  int height,width,step,channels;
  uchar *data;
  int i,j,k;

  if(argc<2){
    printf("Usage: main <image-file-name>\n\7");
    exit(0);
  }

  // load an image  
  img=cvLoadImage(argv[1],CV_LOAD_IMAGE_COLOR );
  if(!img){
    printf("Could not load image file: %s\n",argv[1]);
    exit(0);
  }

  // get the image data
  height    = img->height;
  width     = img->width;
  step      = img->widthStep;
  channels  = img->nChannels;
  data      = (uchar *)img->imageData;
  printf("Processing a %dx%d image with %d channels\n",height,width,channels); 

  // create a window
  cvNamedWindow("mainWin", CV_WINDOW_AUTOSIZE); 
  cvMoveWindow("mainWin", 100, 100);

  // invert the image
 // for(i=0;i<height;i++) for(j=0;j<width;j++) for(k=0;k<channels;k++)
  //  data[i*step+j*channels+k]=255-data[i*step+j*channels+k];

  // show the image
  cvShowImage("mainWin", img );

  // wait for a key
  cvWaitKey(0);

  // release the image
  cvReleaseImage(&img );
  
  
   printf("OpenCV version = %s\r\n", CV_VERSION);
  return 0;
}

mysz edytuj

/*
http://www.cs.iit.edu/~agam/cs512/lect-notes/opencv-intro/

gcc h.c  `pkg-config --cflags --libs opencv`



*/
////////////////////////////////////////////////////////////////////////
//
// h.c
//
// This is a simple, introductory OpenCV program. The program reads an
// image from a file, inverts it, and displays the result. 
//
////////////////////////////////////////////////////////////////////////
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <cv.h>
#include <highgui.h> // highgui_c.h


int height,width,step,channels;
 uchar *data;


// https://opencv-srf.blogspot.com/2011/11/mouse-events.html
// http://opencvexamples.blogspot.com/2014/01/detect-mouse-clicks-and-moves-on-image.html
// https://www.codeproject.com/Articles/526218/An-introduction-to-OpenCV-Part-II-Implementing-mou

void OnMouse(int event, int x, int y, int flags, void* param)
{

	IplImage* image = (IplImage*) param; // https://www.safaribooksonline.com/library/view/learning-opencv/9780596516130/ch04s04.html
	
     if  ( event == CV_EVENT_LBUTTONDOWN )
     {
          //cout << "Left button of the mouse is clicked - position (" << x << ", " << y << ")" << endl;
     }
     else if  ( event == CV_EVENT_RBUTTONDOWN )
     {
          //cout << "Right button of the mouse is clicked - position (" << x << ", " << y << ")" << endl;
     }
     else if  ( event == CV_EVENT_MBUTTONDOWN )
     {
          //cout << "Middle button of the mouse is clicked - position (" << x << ", " << y << ")" << endl;
     }
     else if ( event == CV_EVENT_MOUSEMOVE )
     {
         // cout << "Mouse move over the window - position (" << x << ", " << y << ")" << endl;
         printf(" x= %d ; y = %d B = %d G = %d R = %d\n ", x, y, data[y*step+x*channels+0],  data[y*step+x*channels+1],  data[y*step+x*channels+2]);
    	

     }
}




int main(int argc, char *argv[])
{
  IplImage* img = 0; 
  
 
  int i,j,k;
   
  
  

  if(argc<2){
    printf("Usage: main <image-file-name>\n\7");
    exit(0);
  }

  // load an image  
  img=cvLoadImage(argv[1],CV_LOAD_IMAGE_COLOR );
  if(!img){
    printf("Could not load image file: %s\n",argv[1]);
    exit(0);
  }
  
  
    

  // get the image data
  height    = img->height;
  width     = img->width;
  step      = img->widthStep;
  channels  = img->nChannels;
  data      = (uchar *)img->imageData;
  printf("Processing a %dx%d image with %d channels\n",height,width,channels); 

  // create a window
  cvNamedWindow("mainWin", CV_WINDOW_AUTOSIZE); 
  cvMoveWindow("mainWin", 100, 100);

  // invert the image
 // for(i=0;i<height;i++) for(j=0;j<width;j++) for(k=0;k<channels;k++)
  //  data[i*step+j*channels+k]=255-data[i*step+j*channels+k];

   //set the callback function for any mouse event
   // https://stackoverflow.com/questions/15570431/opencv-return-value-from-mouse-callback-function
   // 
  cvSetMouseCallback("mainWin", OnMouse, (void*) img);
  //  here 


  // show the image
  cvShowImage("mainWin", img );

  // wait for a key
  cvWaitKey(0);

  // release the image
  cvReleaseImage(&img );
  
  
   printf("OpenCV version = %s\r\n", CV_VERSION);
  return 0;
}

c++ edytuj

 #include <opencv2/core/core.hpp>
 #include <opencv2/highgui/highgui.hpp>

kompilacja:

g++ o.cpp `pkg-config --cflags --libs opencv4` -I/usr/include/opencv4

plik pc

/usr/local/lib/opencv4.pc

pierwszy program, wersja edytuj

// https://www.solarianprogrammer.com/2014/04/21/opencv-beaglebone-black-ubuntu/
// Test to check the OpenCV version
// Build on Linux with:
 // g++ test_1.cpp -o test_1 -lopencv_core
 
#include <opencv2/opencv.hpp>
#include <iostream>
 
 int main() {
 	std::cout << "Hello, OpenCV version "<< CV_VERSION << std::endl;
 	return 0;
 }

Przykłądowy wynik :

 Hello, OpenCV version 2.4.9.1

otwieranie obrazów i gui edytuj

// http://docs.opencv.org/master/db/df5/tutorial_linux_gcc_cmake.html
// DisplayImage.cpp
#include <stdio.h>
#include <opencv2/opencv.hpp>
using namespace cv;
int main(int argc, char** argv )
{
    if ( argc != 2 )
    {
        printf("usage: DisplayImage.out <Image_Path>\n");
        return -1;
    }
    Mat image;
    image = imread( argv[1], 1 );
    if ( !image.data )
    {
        printf("No image data \n");
        return -1;
    }
    namedWindow("Display Image", WINDOW_AUTOSIZE );
    imshow("Display Image", image);
    waitKey(0);
    return 0;
}

CMakeLists.txt :

cmake_minimum_required(VERSION 2.8)
project( DisplayImage )
find_package( OpenCV REQUIRED )
include_directories( ${OpenCV_INCLUDE_DIRS} )
add_executable( DisplayImage DisplayImage.cpp )
target_link_libraries( DisplayImage ${OpenCV_LIBS} )

kompilacja :

cmake .
make

uruchomienie

 ./DisplayImage lena.jpg

Gradient edytuj

// original code by http://stackoverflow.com/users/951860/mevatron
// see http://stackoverflow.com/a/11157426/15485
// http://stackoverflow.com/users/15485/uvts-cvs added the code for saving x and y gradient component 

#include <opencv2/opencv.hpp>
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/imgproc/imgproc.hpp>

#include <iostream>
#include <vector>

using namespace cv;
using namespace std;

Mat mat2gray(const cv::Mat& src)
{
    Mat dst;
    normalize(src, dst, 0.0, 255.0, cv::NORM_MINMAX, CV_8U);

    return dst;
}

Mat orientationMap(const cv::Mat& mag, const cv::Mat& ori, double thresh = 1.0)
{
    Mat oriMap = Mat::zeros(ori.size(), CV_8UC3);
    Vec3b red(0, 0, 255);
    Vec3b cyan(255, 255, 0);
    Vec3b green(0, 255, 0);
    Vec3b yellow(0, 255, 255);
    for(int i = 0; i < mag.rows*mag.cols; i++)
    {
        float* magPixel = reinterpret_cast<float*>(mag.data + i*sizeof(float));
        if(*magPixel > thresh)
        {
            float* oriPixel = reinterpret_cast<float*>(ori.data + i*sizeof(float));
            Vec3b* mapPixel = reinterpret_cast<Vec3b*>(oriMap.data + i*3*sizeof(char));
            if(*oriPixel < 90.0)
                *mapPixel = red;
            else if(*oriPixel >= 90.0 && *oriPixel < 180.0)
                *mapPixel = cyan;
            else if(*oriPixel >= 180.0 && *oriPixel < 270.0)
                *mapPixel = green;
            else if(*oriPixel >= 270.0 && *oriPixel < 360.0)
                *mapPixel = yellow;
        }
    }

    return oriMap;
}

int main(int argc, char* argv[])
{
    Mat image = Mat::zeros(Size(320, 240), CV_8UC1);
    circle(image, Point(160, 120), 80, Scalar(255, 255, 255), -1, CV_AA);

    imshow("original", image);

    Mat Sx;
    Sobel(image, Sx, CV_32F, 1, 0, 3);

    Mat Sy;
    Sobel(image, Sy, CV_32F, 0, 1, 3);

    Mat mag, ori;
    magnitude(Sx, Sy, mag);
    phase(Sx, Sy, ori, true);

    Mat oriMap = orientationMap(mag, ori, 1.0);

    imshow("x", mat2gray(Sx));
    imshow("y", mat2gray(Sy));

    imwrite("hor.png",mat2gray(Sx));
    imwrite("ver.png",mat2gray(Sy));

    imshow("magnitude", mat2gray(mag));
    imshow("orientation", mat2gray(ori));
    imshow("orientation map", oriMap);
    waitKey();

    return 0;
}

CMakeLists.txt :

cmake_minimum_required(VERSION 2.8)
project( g )
find_package( OpenCV REQUIRED )
include_directories( ${OpenCV_INCLUDE_DIRS} )
add_executable( g g.cpp )
target_link_libraries( g ${OpenCV_LIBS} )

Kompilacja :

 cmake .
 make

Uruchomienie

./g

pfm edytuj

PFM_ReadWrite in c++ by Antoine Toisoul Le Cann and version for OpenCV 3

js edytuj

opencv js doc

open file edytuj

Otwieranie pliku ^[9]

 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>Hello OpenCV.js</title>
</head>
<body>
  <h2>Hello OpenCV.js</h2>
  <p id="status">OpenCV.js is loading...</p>
  <div>
    <div class="inputoutput">
      <img id="imageSrc" alt="No Image" />
      <div class="caption">imageSrc <input type="file" id="fileInput" name="file" /></div>
    </div>
    <div class="inputoutput">
      <canvas id="canvasOutput"></canvas>
      <div class="caption">canvasOutput</div>
    </div>
  </div>
  <script type="text/javascript">
    let imgElement = document.getElementById('imageSrc');
    let inputElement = document.getElementById('fileInput');
    inputElement.addEventListener('change', (e) => {
      imgElement.src = URL.createObjectURL(e.target.files[0]);
    }, false);
    imgElement.onload = function () {
      let mat = cv.imread(imgElement);
      cv.imshow('canvasOutput', mat);
      mat.delete();
    };
    var Module = {
      // https://emscripten.org/docs/api_reference/module.html#Module.onRuntimeInitialized
      onRuntimeInitialized() {
        document.getElementById('status').innerHTML = 'OpenCV.js is ready.';
      }
    };
  </script>
  <script async src="https://docs.opencv.org/master/opencv.js" type="text/javascript"></script>
</body>
</html>

python edytuj

Program do analizy obrazu^[10]

nie korzysta z pętli fo i CPU ( są one powolne i podatne na błędy )
wykorzystuje wektoryzację z pomocą bibliotek Numpy lub OpenCV.

  
import cv2
import numpy as np

# Load image
im = cv2.imread('Mushroom1.jpg', cv2.IMREAD_GRAYSCALE)

# Calculate total number of pixels in image
nPixels = im.size

# Iterate over the possible threshold values, skipping 10 at a time for speed of development/checking
for T in range(1,255,10):
   # Make all pixels under threshold black, leaving those above threshold unchanged
   thresholded = (im < T) * im
   # Count the non-zero pixels
   nonZero = cv2.countNonZero(thresholded)
   Zero = nPixels - nonZero
   # Sum the non-zero pixels
   sum = np.sum(thresholded)
   # Print some statistics
   print(f'T={T}, zero={Zero}, nonZero={nonZero}, sum={sum}')
   # Save the image for animation
   cv2.imwrite(f'DEBUG-T{T:03}.png', thresholded)

gui edytuj

GUI and OpenCV^[11]

python
C++
- highgui
- Image-Processing-with-OpenCV-C++
- OpenCVGUI - github
- zGUI
- cvui learnopencv: cvui-gui-lib-built-on-top-of-opencv-drawing-primitives

pomoc edytuj

strona domowa: http://opencv.org
dokumentacja: http://docs.opencv.org/master/
forum: http://answers.opencv.org
learnopencv
pyimagesearch The fastest way to learn OpenCV, Object Detection, and Deep Learning.
https://github.com/opencv/opencv/issues
http://stackoverflow.com/search?q=opencv
https://help.ubuntu.com/community/OpenCV
http://www.cs.iit.edu/~agam/cs512/lect-notes/opencv-intro/
https://github.com/MartinThoma/algorithms/blob/master/OpenCV/mat-example/Makefile
code project : OpenCV
stackoverflow : opencv
stackoverflow tag info : opencv
RIP tutorial : OpenCV
linuxfromscratch blfs

zobacz również edytuj

Źródła edytuj

[1] stackoverflow question :how-to-check-for-opencv-on-ubuntu-9-10

[2] swers.opencv.org : which-one-is-preferred-to-use-c-or-c

[3] v linux install

[4] stackoverflow question: how-to-check-for-opencv-on-ubuntu-9-10

[5] stackoverflow question find-opencv-version-installed-on-ubuntu

[6] s.opencv.org 2.4 : modules highgui

[7] stackoverflow question : how-to-make-a-simple-window-with-one-button-using-opencv-highgui-only

[8] stackoverflow question: is-there-a-working-c-interface-for-opencv-3-x

[9] v : get-started

[10] stackoverflow question: is-there-any-good-command-to-get-pixels-gray-value-in-this-case-im-working-on

[11] stackoverflow question : opencv-and-creating-guis

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

Programowanie w systemie UNIX/OpenCV

Spis treści

Zależności edytuj

wymagane edytuj

opcjonalne edytuj

pliki edytuj

Lokalizacja edytuj

Wersje edytuj

biblioteki edytuj

językowe edytuj

Instalacja edytuj

git edytuj

wersja edytuj

sprawdzanie edytuj

Funkcje edytuj

moduły edytuj

Przykłady edytuj

c edytuj

wersja edytuj

gui i otwieranie obrazów edytuj

mysz edytuj

c++ edytuj

pierwszy program, wersja edytuj

otwieranie obrazów i gui edytuj

Gradient edytuj

pfm edytuj

js edytuj

open file edytuj

python edytuj

gui edytuj

pomoc edytuj

zobacz również edytuj

Źródła edytuj