ImageParser.java

package org.sparkexample; /** * sample program to read images belonging to a sample Class e.g. Male/Female . Then writing the images to Vector format into a text file. These text files will be used by Apache Spark for Linear SVM analysis */

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.awt.image.Raster;
import java.io.*;
import java.nio.file.*;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.ArrayList;
import java.util.List;

/**
 * @author smruti
 * @author fornarat

usage:
java com.hyperiongray.ImageParser 180x200 /home/tomas/projects/spark/img-data/faces94/male/ 1
java com.hyperiongray.ImageParser 180x200 /home/tomas/projects/spark/img-data/faces94/female/ 0

 */

/**

 creates a txt file with the pixels of the image
 */
public class ImageParserRGB {

    public static void main(String[] args)  throws IOException {


    /* args[0] is the pixel to which the image will  be converted */
        String[] pixels = args[0].split("x");

        int scaledWidth = Integer.parseInt(pixels[0]);
        int scaledHeight = Integer.parseInt(pixels[1]);

        /* args[1] is the parent path of images to dump */
        String providedParentPath = args[1].toString();

        /* args[2] is the Class of the image, Class = Male/Female. Vector will be written into a text file */
        String label = args[2];
        String outputFilename = args[3];

        ImageParserRGB imageParser = new ImageParserRGB();
        imageParser.extract(providedParentPath, scaledWidth, scaledHeight, label, outputFilename);

    }

    public void extract(String providedParentPath, int scaledWidth, int scaledHeight, String label, String outputFilename) throws IOException {

        List<String> paths = getRecursiveFolders(providedParentPath);


        try {
            try(PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter(outputFilename +".csv", true)))) {
                for(String file : paths){
                    File input = new File(file.toString());
                    BufferedImage image = createResizedCopy(ImageIO.read(input),scaledWidth,scaledHeight,Boolean.TRUE);
                    toGray(image);
                    if (image == null) continue;
                    Raster raster=image.getData();
                    int w=raster.getWidth();
                    int h=raster.getHeight();
                    out.print(label +",");
                    for (int x=0;x<w;x++){
                        for(int y=0;y<h;y++){
                            out.print(raster.getSample(x,y,0));
                            if (x!=w-1 || y!=h-1){
                                out.print(",");
                            }
                        }
//                        out.print(",");
                    }

                    out.println("");
                }
            }catch (IOException e) {
                //exception handling skipped for the reader
                System.out.println(e);
            }
        }
        catch (Exception e) {
            System.out.println(e);
            //exception handling skipped for the reader
        }
    }

    /**
     * Traverse All the files inside the Folder and sub folder. args[1] is the path of the folder having the images
     * @param providedParentPath
     * @return
     * @throws IOException
     */
    private List<String> getRecursiveFolders(String providedParentPath) throws IOException {
        List<String> paths = new ArrayList<>();
        Files.walkFileTree(Paths.get(providedParentPath), new SimpleFileVisitor<Path>() {
            @Override
            public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException {
                //Files.delete(file);
                paths.add(file.toFile().getAbsolutePath());
                return FileVisitResult.CONTINUE;
            }

            @Override
            public FileVisitResult postVisitDirectory(Path dir, IOException exc) throws IOException {
                //Files.delete(dir);
                return FileVisitResult.CONTINUE;
            }

        });
        return paths;
    }



    public void toGray(BufferedImage image) {
        int width = image.getWidth();
        int height = image.getHeight();
        for(int i=0; i<height; i++){
            for(int j=0; j<width; j++){
                Color c = new Color(image.getRGB(j, i));
                int red = (int)(c.getRed() * 0.21);
                int green = (int)(c.getGreen() * 0.72);
                int blue = (int)(c.getBlue() *0.07);
                int sum = red + green + blue;
                Color newColor = new Color(sum,sum,sum);
                image.setRGB(j,i,newColor.getRGB());
            }
        }
    }

    public BufferedImage createResizedCopy(BufferedImage originalImage,
                                           int scaledWidth, int scaledHeight,
                                           boolean preserveAlpha){
        System.out.println("resizing...");
        int imageType = preserveAlpha ? BufferedImage.TYPE_INT_RGB : BufferedImage.TYPE_INT_ARGB;
        BufferedImage scaledBI = new BufferedImage(scaledWidth, scaledHeight, imageType);
        Graphics2D g = scaledBI.createGraphics();
        if (preserveAlpha) {
            g.setComposite(AlphaComposite.Src);
        }
        g.drawImage(originalImage, 0, 0, scaledWidth, scaledHeight, null);
        g.dispose();
        return scaledBI;
    }

}