TextImage.java

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.io.File;
import java.awt.image.*;
import javax.imageio.*;

public class TextImage {
 
	public static void main(String[] args) {
 
		String name, inf, outf;
		if (args.length<1) name = "smile";
		else name = args[0];

		int type = BufferedImage.TYPE_INT_RGB;
		BufferedImage out = null;
		int value[] = null;
		int v,r,g,b;
		int npix=0;
		int j=0;
 
		inf = name + ".txt";
		try (
			BufferedReader br = new BufferedReader(new FileReader(inf));
 
		) {
 
			String s;
 

			while ((s = br.readLine()) != null) {
				String [] tokens = s.trim().split("[\\s]+");
				if (out==null) {
					npix = tokens.length;
					System.out.format("image size %d x %d\n",npix,npix);
					out = new BufferedImage(npix,npix,type);
					value = new int[npix];
				}				
				for (int i=0; i<npix; i++) {
					v = Integer.parseInt(tokens[i])&0xFF;
					value[i] = 0xFF000000 | (v << 16) | (v << 8) | v;
				}
	    			out.setRGB(0, j++, npix, 1, value, 0, npix);
			}
			br.close();
 
		} catch (IOException e) {
			System.out.println("file not found: " + inf);
			//e.printStackTrace();
		} 

		outf = name + ".png";
		try {
			ImageIO.write(out, "png", new File(outf));
		} catch (IOException e) {
			System.out.println("image write failed");
			System.out.println(e);
			System.exit(-1);
		}
	}
}