Java Articles

Page 329 of 450

How to convert colored image to HLS using Java OpenCV library?

Maruthi Krishna
Maruthi Krishna
Updated on 09-Apr-2020 261 Views

You can convert HLS image to RGB (colored) image by passing Imgproc.COLOR_RGB2HLS as the 3rd parameter to the cvtColor() method.Exampleimport org.opencv.core.Core; import org.opencv.core.Mat; import org.opencv.imgcodecs.Imgcodecs; import org.opencv.imgproc.Imgproc; public class HSL2RGB {    public static void main(String args[]) throws Exception {       System.loadLibrary( Core.NATIVE_LIBRARY_NAME );       Mat src = Imgcodecs.imread("D:\images\car3.jpg");       Mat dst = new Mat();       Imgproc.cvtColor(src, dst, Imgproc.COLOR_RGB2HLS);       Imgcodecs imageCodecs = new Imgcodecs();       imageCodecs.imwrite("D:\images\hslImage.jpg", dst);       System.out.println("Image Saved");    } }InputOutput

Read More

How to convert HLS to colored image using Java OpenCV library?

Maruthi Krishna
Maruthi Krishna
Updated on 09-Apr-2020 285 Views

The cvtColor() method of the Imgproc class changes/converts the color of the image from one to another. This method accepts three parameters −src − A Matrix object representing source.dst − A Matrix object representing the destination.code − An integer value representing the color of the destination image.You can convert a colored image to an HLS image by passing Imgproc.COLOR_RGB2HLS as a parameter to the above method.Exampleimport org.opencv.core.Core; import org.opencv.core.Mat; import org.opencv.imgcodecs.Imgcodecs; import org.opencv.imgproc.Imgproc; public class RGB2HSL {    public static void main(String args[]) throws Exception {       //Loading the OpenCV core library       System.loadLibrary( Core.NATIVE_LIBRARY_NAME ); ...

Read More

How to convert HSV to colored image using Java OpenCV library?

Maruthi Krishna
Maruthi Krishna
Updated on 09-Apr-2020 394 Views

The cvtColor() method of the Imgproc class changes/converts the color of the image from one to another. This method accepts three parameters −src − A Matrix object representing source.dst − A Matrix object representing the destination.code − An integer value representing the color of the destination image.To convert an HSV image to RGB you need to pass Imgproc.COLOR_HSV2RGB as the third parameter to this method.Exampleimport org.opencv.core.Core; import org.opencv.core.Mat; import org.opencv.imgcodecs.Imgcodecs; import org.opencv.imgproc.Imgproc; public class HSV2RGB {    public static void main(String args[]) throws Exception {       //Loading the OpenCV core library       System.loadLibrary( Core.NATIVE_LIBRARY_NAME );     ...

Read More

How to convert RGB image to HSV using Java OpenCV library?

Maruthi Krishna
Maruthi Krishna
Updated on 09-Apr-2020 1K+ Views

The cvtColor() method of the Imgproc class changes/converts the color of the image from one to another. This method accepts three parameters −src − A Matrix object representing source.dst − A Matrix object representing the destination.code − An integer value representing the color of the destination image.To convert an RGB image to HSV you need to pass Imgproc.COLOR_RGB2HSV as the third parameter to this method.Exampleimport org.opencv.core.Core; import org.opencv.core.Mat; import org.opencv.imgcodecs.Imgcodecs; import org.opencv.imgproc.Imgproc; public class RGB2HSV {    public static void main(String args[]) throws Exception {       //Loading the OpenCV core library       System.loadLibrary( Core.NATIVE_LIBRARY_NAME );   ...

Read More

Altering the brightness and contrast of an image using JavaFX and OpenCV

Maruthi Krishna
Maruthi Krishna
Updated on 09-Apr-2020 736 Views

The convertTo() method of the org.opencv.core.Mat class accepts 4 parameters namely: mat(empty matrix), rtype(integer), alpha(integer), beta(integer), in the same order.To increase the brightness − You need to reduce the beta value from 0 towards -255(keeping alpha value 1).To decrease the brightness − You need to increase the beta value from 0 towards 255(keeping alpha value 1).To increase the contrast − You need to increase the alpha value from 1 towards 100(keeping beta value 0).To decrease the contrast − You need to decrease the alpha value from 1 to 0 (keeping beta value 0).ExampleFollowing is a JavaFX program with two slide ...

Read More

How to alter the sharpness of an image using Java OpenCV library?

Maruthi Krishna
Maruthi Krishna
Updated on 09-Apr-2020 2K+ Views

Sharpening an image is the opposite of blur. To alter the sharpness of an image using the OpenCV library, you need to smooth/blur it using the Gaussian filter and subtract the smoothed version from the original image.Exampleimport org.opencv.core.Core; import org.opencv.core.Mat; import org.opencv.core.Size; import org.opencv.imgcodecs.Imgcodecs; import org.opencv.imgproc.Imgproc; public class AlteringSharpness {    public static void main (String[] args) {       //Loading the OpenCV core library       System.loadLibrary( Core.NATIVE_LIBRARY_NAME );       //Reading the Image from the file       String file ="D:\Image\lamma1.jpg";       Mat src = Imgcodecs.imread(file, Imgcodecs.IMREAD_COLOR);       //Creating an ...

Read More

How to compare two images using Java OpenCV library?

Maruthi Krishna
Maruthi Krishna
Updated on 09-Apr-2020 7K+ Views

To compare two images −Read Both of them using the Image.IO.read() method.Get the height and width of both of them to make sure they are equal.Get the pixel values and, get the RGB values of both of the images.Get the sum of the differences between the RGB values of these two images.Calculate the percentage of the difference using the following formula −Average = difference/weight*height*3; Percentage = (Average/255)*100;Exampleimport java.awt.Color; import java.awt.image.BufferedImage; import javax.imageio.ImageIO; import java.io.File; public class ComparingImages {    public static void main(String[] args) throws Exception {       BufferedImage img1 = ImageIO.read(new File("D:\Images\test1.jpg"));       BufferedImage img2 ...

Read More

How to flip an image using Java OpenCV library?

Maruthi Krishna
Maruthi Krishna
Updated on 09-Apr-2020 1K+ Views

The flip() method of the Core class of OpenCV flips an image along the x/y axis. This method accepts −A source matrix congaing the data of the original image.An empty destination matrix to hold the data of the resultant image.A flip code to specify the direction of the image (0 –x axis, +ve – y axis, – ve both the axes).To flip an image −Load the OpenCV core native library, using the loadLibrary() method.Read the contents of the image file to a matrix using the imread() method.Create an empty matric to hold the result.Invoke the flip() method by passing the ...

Read More

How to create a mirror image using Java OpenCV library?

Maruthi Krishna
Maruthi Krishna
Updated on 09-Apr-2020 832 Views

To create a mirror imageRead the required image using ImageIO.read() method.Get the height and width of the image.Create an empty buffered image to store the resultUsing nested for loops traverse through each pixel in the image.Iterate the width of the image from right to left.Get the pixel value using the getRGB() method.Set the pixel values to the result image object using the setRGB() method, by replacing the new width values.Exampleimport java.io.File; import java.io.IOException; import java.awt.image.BufferedImage; import javax.imageio.ImageIO; public class MirrorImage {    public static void main(String args[])throws IOException {       //Reading the image       File file= ...

Read More

How to convert a colored image to Sepia image using Java OpenCV library?

Maruthi Krishna
Maruthi Krishna
Updated on 09-Apr-2020 951 Views

Algorithm to convert a colored image to sepia −Get the red green blue values of each pixelGet the average of these 3 colors.Define the depth and intensity values (ideally 20, and 30).Modify the values as −red = red + (depth*2).Green = green +depth.blue = blue-intensity.Make sure that the modified values are between 0 to 255.Create a new pixel value from the modified colors and set the new value to the pixel.Implementation in JavaRead the required image using ImageIO.read() method.Get the height and width of the image.Using nested for loops traverse through each pixel in the image.Get the pixel value using ...

Read More
Showing 3281–3290 of 4,496 articles
« Prev 1 327 328 329 330 331 450 Next »
Advertisements