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Color palette higher than 255

For my project, I'm able to print textures on objects. As soon I use nicer textures that use a color palette higher than 256 it will turn black or invisible...
Is anyone able to help me with this issue? Right now this is my code to transfer the .png into a useable texture:
public static Background getIndexedImage(int id, File file) throws IOException {
BufferedImage image = ImageIO.read(file);
List<Integer> paletteList = new LinkedList<>();
paletteList.add(0);
int width = image.getWidth();
int height = image.getHeight();
byte[] pixels = new byte[width * height];
for (int x = 0; x < width; x++) {
for (int y = 0; y < height; y++) {
int rgb = image.getRGB(x, y);
int red = rgb >> 16 & 0xff;
int green = rgb >> 8 & 0xff;
int blue = rgb & 0xff;
int alpha = rgb & 0xff;
rgb = red << 16 | green << 8 | blue;
if (alpha == 255) {
rgb = 0;
}
int index = paletteList.indexOf(rgb);
if (index == -1) {
if (paletteList.size() < 256) {
index = paletteList.size();
paletteList.add(rgb);
} else {
throw new IllegalArgumentException("The target image has more than 255 color in the palette "+id);
}
}
pixels[x + y * width] = (byte) index;
}
}
int[] palette = new int[paletteList.size()];
final AtomicInteger index = new AtomicInteger(0);
for (int pallet = 0; pallet < paletteList.size(); pallet++) {
palette[index.getAndIncrement()] = paletteList.get(pallet);
}
return new Background(width, height, palette, pixels);
}

how do I do pixel perfect upscaling in java?

I have a a lot of pixel art images that need to be scaled up to double the size.
It needs to be done so that each pixel in the image turns into a 2x2 set of pixels of the same exact same color, with no blending of colors.
example:
f I use ImageIO to read in a .png image as a BufferedImage with
BufferedImage foo = ImageIO.read(new File("C:\\path\\to\\image.png"));
how would I go about up-scaling it so it wont blend the pixels?

Hope it helps you
import java.awt.image.BufferedImage;
import java.awt.image.DataBufferByte;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
public class ImageCovertTest {
public static void main(String[] args) throws IOException {
BufferedImage foo = ImageIO.read(new File("path/to/image"));
BufferedImage rs = cover(foo, 2);// cover X2
ImageIO.write(rs, "png", new File("path/to/output"));
}
private static int[][] convertToPixels(BufferedImage image) {
final byte[] pixels = ((DataBufferByte) image.getRaster().getDataBuffer()).getData();
final int width = image.getWidth();
final int height = image.getHeight();
final boolean hasAlphaChannel = image.getAlphaRaster() != null;
int[][] result = new int[height][width];
if (hasAlphaChannel) {
final int pixelLength = 4;
for (int pixel = 0, row = 0, col = 0; pixel + 3 < pixels.length; pixel += pixelLength) {
int argb = 0;
argb += (((int) pixels[pixel] & 0xff) << 24); // alpha
argb += ((int) pixels[pixel + 1] & 0xff); // blue
argb += (((int) pixels[pixel + 2] & 0xff) << 8); // green
argb += (((int) pixels[pixel + 3] & 0xff) << 16); // red
result[row][col] = argb;
col++;
if (col == width) {
col = 0;
row++;
}
}
} else {
final int pixelLength = 3;
for (int pixel = 0, row = 0, col = 0; pixel + 2 < pixels.length; pixel += pixelLength) {
int argb = 0;
argb += -16777216; // 255 alpha
argb += ((int) pixels[pixel] & 0xff); // blue
argb += (((int) pixels[pixel + 1] & 0xff) << 8); // green
argb += (((int) pixels[pixel + 2] & 0xff) << 16); // red
result[row][col] = argb;
col++;
if (col == width) {
col = 0;
row++;
}
}
}
return result;
}
public static BufferedImage cover(BufferedImage image, int range) {
int[][] pixels = convertToPixels(image);
int width = image.getWidth();
int height = image.getHeight();
BufferedImage imageResult = new BufferedImage(width* range, height* range, BufferedImage.TYPE_INT_ARGB);
for (int x = 0; x < width * range; x ++){
for (int y = 0; y < height * range; y++) {
imageResult.setRGB(x, y, pixels[y/ range][x/ range]);
}
}
return imageResult;
}
}

Converting certain pixels' RGB color to another color

Programming Language: Java
I am trying to convert certain pixels of this image to a different color to reveal a "Secret Message."
Most of the pixels are:
Red = 0, Green = 64, Blue = 0
The pixels that I want changed to R = 255, G = 255, B = 255 are:
Red = 5, Green = 64, Blue = 5
import java.io.File;
import java.io.IOException;
import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;
import java.awt.Color;
public class ASSN2p2
{
private static int makeRGBColor(int red, int green, int blue)
{
int rgb = 0;
rgb = red*65536 + green*256 + blue;
return rgb;
}
private static int getRed(int pixel)
{
return (pixel >> 16) & 0xFF;
}
private static int getGreen(int pixel)
{
return (pixel >> 8) & 0xFF;
}
private static int getBlue(int pixel)
{
return (pixel) & 0xFF;
}
public static void main(String args[]) throws IOException
{
// int width = 300;
// int height = 200;
BufferedImage image = null;
File f = null;
try
{
f = new File("D:\\2016-2017\\Fall2016\\201_CSCE_Programming\\Assignment 2\\secretmessage.png");
image = ImageIO.read(f);
image = new BufferedImage(image.getWidth(), image.getHeight(), BufferedImage.TYPE_INT_ARGB);
System.out.println("Reading Complete");
BufferedImage output = new BufferedImage(image.getWidth(), image.getHeight(),BufferedImage.TYPE_INT_ARGB);
//--------------------------------------
//-------------------------------------------
for (int y = 0; y < image.getHeight(); y++)
{
for (int x = 0; x < image.getWidth(); x++)
{
int pixel = image.getRGB(x, y);
int r,g,b;
r = getRed(pixel);
g = getGreen(pixel);
b = getBlue(pixel);
if ((r == 5) && (g == 64) && (b == 5))
{
r = 64;
b = 64;
b = 64;
image.setRGB(x,y,makeRGBColor(r,g,b));
} }
}
}
catch(IOException e)
{
System.out.println("Error: "+e);
}
// printPixelARGB(pixel);
// System.out.println("");
try
{
f = new File("D:\\2016-2017\\Fall2016\\201_CSCE_Programming\\Assignment 2\\output.png");
ImageIO.write(image, "png", f);
System.out.println("Writing Complete");
}
catch(IOException e)
{
System.out.println("Error: "+e);
}
}
}
This produces this:
I am having trouble understanding what has gone wrong!
Any assistance will be appreciated!

I believe that you're missing the alpha component of your new color. Change your code to:
private static int makeRGBColor(int red, int green, int blue) {
int rgb = 0xff000000 | (red << 16) | (green << 8) | blue;
return rgb;
}
to make sure that the alpha is set to full, otherwise your image will look completely transparent.

Can't paint on canvas

I've been trying to paint on canvas but i can't make it work, i can see the JFrame but it seems it doesn't call the paint method when the Mover() object is being added to it. This is the first time using canvas so i don't know what am i missing. Here is code:
import java.awt.image.BufferedImage;
import java.awt.image.DataBufferByte;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.*;
import java.util.*;
import java.awt.*;
import java.io.File;
public class Move extends Canvas
{
private static int [][]imgRGB;
public Move()
{
try
{
BufferedImage hugeImage = ImageIO.read(new File("C:/Users/pc/Pictures/Nave.gif"));
imgRGB = convertToRGB(hugeImage);
}
catch(IOException e)
{
System.out.println(e);
}
}
public void Paint(Graphics g)
{
super.paint(g);
for(int i=0 ; i<imgRGB.length ; i++)
{
for(int j=0 ; j<imgRGB[i].length; j++)
{
g.setColor(new Color(imgRGB[i][j]));
g.drawLine(i,j,i,j);
}
}
}
private static int[][] convertToRGB(BufferedImage image) {
final byte[] pixels = ((DataBufferByte) image.getRaster().getDataBuffer()).getData();
final int width = image.getWidth();
final int height = image.getHeight();
final boolean hasAlphaChannel = image.getAlphaRaster() != null;
int[][] result = new int[height][width];
if (hasAlphaChannel) {
final int pixelLength = 4;
for (int pixel = 0, row = 0, col = 0; pixel < pixels.length; pixel += pixelLength) {
int argb = 0;
argb += (((int) pixels[pixel] & 0xff) << 24); // alpha
argb += ((int) pixels[pixel + 1] & 0xff); // blue
argb += (((int) pixels[pixel + 2] & 0xff) << 8); // green
argb += (((int) pixels[pixel + 3] & 0xff) << 16); // red
result[row][col] = argb;
col++;
if (col == width) {
col = 0;
row++;
}
}
} else {
final int pixelLength = 3;
for (int pixel = 0, row = 0, col = 0; pixel < pixels.length; pixel += pixelLength) {
int argb = 0;
argb += -16777216; // 255 alpha
argb += ((int) pixels[pixel] & 0xff); // blue
argb += (((int) pixels[pixel + 1] & 0xff) << 8); // green
argb += (((int) pixels[pixel + 2] & 0xff) << 16); // red
result[row][col] = argb;
col++;
if (col == width) {
col = 0;
row++;
}
}
}
return result;
}
public static void main(String[] args)
{
JFrame container = new JFrame("pixel");
container.add(new Move());
container.setSize(400,400);
container.setVisible(true);
container.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}

public void Paint(Graphics g)
Method names are case sensitive. You should override paint(...).
Always use the #Override annotation and the compiler will notify you when you attempt to override a method that doesn't exist:
#Override
public void paint(Graphics g)
{
...
}
However, you should not be overriding Canvas in a Swing application.
Instead you should extend JPanel and then you should be overriding the paintComponent(...) method.
Read the section from the Swing tutorial on Custom Painting for more information and working examples.

RGB pixel array only one dimension not 3 in vector

Hi. I want rgb values in this format: In a 1d vector I want first R values, then G values, and then B Values. I tried to use this code:
pixels = new int[bitmap.getHeight() * bitmap.getWidth()];
bitmap.getPixels(pixels, 0, bitmap.getWidth(), 0, 0,
bitmap.getWidth(), bitmap.getHeight());
// int R, G, B,Y;
for (int y = 0; y < bitmap.getHeight(); y++) {
for (int x = 0; x < bitmap.getWidth(); x++) {
int index = y * bitmap.getHeight() + x;
int R = (pixels[index] >> 16) & 0xff; // bitwise shifting
int G = (pixels[index] >> 8) & 0xff;
int B = pixels[index] & 0xff;
// R,G.B - Red, Green, Blue
// to restore the values after RGB modification, use
// next statement
pixels[index] = 0xff000000 | (R << 16) | (G << 8) | B;
}
}
bitmap.recycle();
} catch (NullPointerException exception) {
Log.e("Error Utils",
"Photo is damaged or does not support this format!");
}
return pixels;
But, I still have only a 300*200 1d array.
Not 300*200*3 1d array!

Maybe it's that what you try to do
public static int[] getPixel(Bitmap bitmap) {
final int width = bitmap.getWidth();
final int height = bitmap.getHeight();
int[] pixelIn = new int[width * height];
bitmap.getPixels(pixelIn, 0, width, 0, 0, width, height);
bitmap.recycle();
int[] pixelOut = new int[width * height * 3];
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
int index = y * height + x;
int R = (pixelIn[index] >> 16) & 0xff;
int G = (pixelIn[index] >> 8) & 0xff;
int B = (pixelIn[index] >> 0) & 0xff;
int indexOut = index * 3;
pixelOut[indexOut++] = R;
pixelOut[indexOut++] = G;
pixelOut[indexOut ] = B;
}
}
return pixelOut;
}
Untested but it should create an int[] (you should consider byte[]) that is filled [R][G][B][R][G][B]...
same for bytes
public static byte[] getPixelBytes(Bitmap bitmap) {
final int width = bitmap.getWidth();
final int height = bitmap.getHeight();
final int total = width * height;
int[] pixelIn = new int[total];
bitmap.getPixels(pixelIn, 0, width, 0, 0, width, height);
bitmap.recycle();
byte[] pixelOut = new byte[total * 3];
int indexOut = 0;
for (int pixel : pixelIn) {
byte R = (byte) ((pixel >> 16) & 0xff);
byte G = (byte) ((pixel >> 8) & 0xff);
byte B = (byte) ((pixel ) & 0xff);
pixelOut[indexOut++] = R;
pixelOut[indexOut++] = G;
pixelOut[indexOut++] = B;
}
return pixelOut;
}
And to get it in three separate arrays like [R R R R][G G G G][B B B B]
public static byte[][] getPixelBytes(Bitmap bitmap) {
final int width = bitmap.getWidth();
final int height = bitmap.getHeight();
final int total = width * height;
int[] pixelIn = new int[total];
bitmap.getPixels(pixelIn, 0, width, 0, 0, width, height);
bitmap.recycle();
byte[][] result = new byte[3][total];
int index = 0;
for (int pixel : pixelIn) {
byte R = (byte) ((pixel >> 16) & 0xff);
byte G = (byte) ((pixel >> 8) & 0xff);
byte B = (byte) ((pixel ) & 0xff);
result[0][index] = R;
result[1][index] = G;
result[2][index] = B;
index++;
}
return result;
}
The rgb values of the 5th (= index 4) pixel would be
byte R = result[0][4];
byte G = result[1][4];
byte B = result[2][4];
Or to separate that into 3 arrays
byte[] rArray = result[0]; // each 0 .. (width x height - 1)
byte[] gArray = result[1];
byte[] bArray = result[2];
Also don't forget that Java's byte is -128..127, not 0..255.