this is my code :
for (int ii = 0; ii <= 17; ii++) {
System.out.println(ii);
if(ii == 10) continue;
String name = String.valueOf(ii);
File pic = new File(name + ".jpg");
BufferedImage image = ImageIO.read(pic);
int w ;
int h ;
int x_max = 0;
int x_min = 1000;
int y_max = 0;
int y_min = 1000;
for (int i = 0; i < image.getWidth(); i++) {
for (int j = 0; j < image.getHeight(); j++) {
Color c = new Color(image.getRGB(i, j));
if(c.getBlue() == 0){
x_max = Math.max(x_max, i);
x_min = Math.min(x_min, i);
y_max = Math.max(y_max, j);
y_min = Math.min(y_min, j);
}
}
}
BufferedImage imagea = image;
image = imagea.getSubimage(x_min - 1, y_min - 1,x_max - x_min + 3 , y_max - y_min + 3);
h = Math.abs(y_max - y_min);
w = Math.abs(x_max - x_min);}
and this is output :
0
1
2
3
4
5
6
7
Exception in thread "main" java.awt.image.RasterFormatException: (x + width) is outside of Raster
at sun.awt.image.ByteInterleavedRaster.createWritableChild(Unknown Source)
at java.awt.image.BufferedImage.getSubimage(Unknown Source)
at element.main(element.java:41)
the error is about "getsubimage" function but i dont know its reason.
the code work until eighth image and dont work for it.
how work "getsubimage" function in java?
This line:
image = imagea.getSubimage(x_min - 1, y_min - 1,x_max - x_min + 3 , y_max - y_min + 3);
Assumes that the resulting coordinates are at least 1 pixel offset from the left and upper edge, and 3 pixels offset from the left and bottom edge. Don't assume that, or make sure they will.
Related
I was beginning with coding in Processing when I encountered an error which I can't find a solution for.
**DISCLAIMER: I'm new to coding, so I'm having trouble understanding how it works lol
I was attempting to use processing to write a code for a kinect program that would create a ripple effect, but I can't figure out how to define two variables.
Code:
// A simple ripple effect. Click on the image to produce a ripple
// Author: radio79
// Code adapted from http://www.neilwallis.com/java/water.html
// Code adapted from https://forum.processing.org/two/discussion/25348/can-i-apply-ripple-effect-to-kinect
import org.openkinect.processing.*;
Kinect kinect;
PImage img;
Ripple ripple;
void setup() {
size(1920, 1080);
kinect = new Kinect(this);
kinect.initVideo();
img = new PImage(kinect.colorWidth, kinect.colorHeight);
ripple = new Ripple();
//frameRate(60);
}
void draw() {
image(kinect.getVideoImage(), 0, 0);
img.loadPixels();
for (int loc = 0; loc < Kinect.colorWidth * Kinect.colorHeight; loc++) {
img.pixels[loc] = ripple.col[loc];
}
img.updatePixels();
ripple.newframe();
}
class Ripple {
int i, a, b;
int oldind, newind, mapind;
short ripplemap[]; // the height map
int col[]; // the actual pixels
int riprad;
int rwidth, rheight;
int ttexture[];
int ssize;
Ripple() {
// constructor
riprad = 3;
rwidth = width >> 1;
rheight = height >> 1;
ssize = width * (height + 2) * 2;
ripplemap = new short[ssize];
col = new int[width * height];
ttexture = new int[width * height];
oldind = width;
newind = width * (height + 3);
}
void newframe() {
// update the height map and the image
i = oldind;
oldind = newind;
newind = i;
i = 0;
mapind = oldind;
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
short data = (short)((ripplemap[mapind - width] + ripplemap[mapind + width] +
ripplemap[mapind - 1] + ripplemap[mapind + 1]) >> 1);
data -= ripplemap[newind + i];
data -= data >> 5;
if (x == 0 || y == 0) // avoid the wraparound effect
ripplemap[newind + i] = 0;
else
ripplemap[newind + i] = data;
// where data = 0 then still, where data > 0 then wave
data = (short)(1024 - data);
// offsets
a = ((x - rwidth) * data / 1024) + rwidth;
b = ((y - rheight) * data / 1024) + rheight;
//bounds check
if (a >= width)
a = width - 1;
if (a < 0)
a = 0;
if (b >= height)
b = height-1;
if (b < 0)
b=0;
col[i] = img.pixels[a + (b * width)];
mapind++;
i++;
}
}
}
}
void mouseDragged() {
for (int j = mouseY - ripple.riprad; j < mouseY + ripple.riprad; j++) {
for (int k = mouseX - ripple.riprad; k < mouseX + ripple.riprad; k++) {
if (j >= 0 && j < height && k>= 0 && k < width) {
ripple.ripplemap[ripple.oldind + (j * width) + k] += 512;
}
}
}
}
The error is: 'The global variable "x" does not exist', 'The global variable "y" does not exist' and so forth. Please help.
The variables I need help defining appear on line 18 for the first time, they are colorWidth and colorHeight
The line reads:
img = new PImage(kinect.colorWidth, kinect.colorHeight);
The colorWidth and colorHeight are underlined in red.
I have tried using this method:
public
float colorWidth;
float colorHeight;
But, only the second line appears to be defined properly. The first line emits the message "colorWidth cannot be resolved or is not a field" when the program runs, or "illegal modifier for parameter colorWidth; only final is permitted" when the underline is clicked.
Picture of what the program shows after the public code
PLEASE HELP!!! Thank you!
The keyword public here just means nothing, it must be said of a function or variable. And you just don't need it. So removing it should fix the problem!
I'm trying to divide a jpg file into 8x8 sub images.
My output gives me 64 identical png files, seemingly all with coordinates (0,0).
According to an older issue Issues with cropping an image using java image.getSubimage this was once a bug which was solved by upgrading to java 7.
I'm using jdk-11.0.9.11-hotspot.
My code:
public static void main(String[] args) throws Exception {
int columnCount = 8;
int rowCount = 8;
String fileName = args[0];//e.g. C:\picturetest\mypicture.jpg
String fileNameNoExt = fileName.substring(0, fileName.lastIndexOf("."));
BufferedImage image = ImageIO.read(new File(fileName));
int heightFragment = image.getHeight() / rowCount;
int widthFragment = image.getWidth() / columnCount;
for (int x = 0; x < columnCount; x++) {
for (int y = 0; y < rowCount; y++) {
ImageIO.write(image
.getSubimage(x, y, widthFragment, heightFragment), "jpg", new File(fileNameNoExt + "-(" + x + "," + y + ").png"));
}
}
}
They are not all starting at (0,0) - but they are starting at the positions (0,0); (0,1); (0,2) and so on until the last starts at (7,7).
You want to increase the top/left coordinates not by 1, but by widthFragment and heightFragment.
One way to do this is:
for (int x = 0; x < columnCount; x++) {
for (int y = 0; y < rowCount; y++) {
ImageIO.write(image
.getSubimage(x*widthFragment, y*heightFragment, widthFragment, heightFragment), "jpg", new File(fileNameNoExt + "-(" + x + "," + y + ").png"));
}
}
Or you change the step sizes for x and y:
for (int x = 0; x < image.getWidth(); x += widthFragment) {
for (int y = 0; y < image.getHeight(); y += heightFragment) {
ImageIO.write(image
.getSubimage(x, y, widthFragment, heightFragment), "jpg", new File(fileNameNoExt + "-(" + x/widthFragment + "," + y/heightFragment + ").png"));
}
}
I want to pixelize a Image with JavaFx.
My problem is that I only have one written pixel in the end, so that it works for just one time.
i tried a
Here is my code:
Image img = imgView.getImage();
PixelReader pixelReader = img.getPixelReader();
WritableImage wImage = new WritableImage(
(int) img.getWidth(),
(int) img.getHeight());
PixelWriter pixelWriter = wImage.getPixelWriter();
for (int y = 1; y < img.getHeight(); y += 3) {
for (int x = 1; x < img.getWidth(); x += 3) {
Color px = pixelReader.getColor(x, y);
float red = (float) px.getRed();
float green = (float) px.getGreen();
float blue = (float) px.getBlue();
Color all = new Color(red / 3, green / 3, blue / 3, 1);
for (int u = 0; u <= 3; u++) {
for (int i = 0; i <= 3; i++) {
pixelWriter.setColor(u, i, all);
}
}
}
}
Just check the part where you set the color:
for (int u = 0; u <= 3; u++) {
for (int i = 0; i <= 3; i++) {
pixelWriter.setColor(u, i, all);
}
}
As you can see you always set the color of pixel at (0,0) - (3,3).
You need to use
pixelWriter.setColor(x + u, y + i, all);
However, you need to be sure that you won't try to set color of some pixels outside the image. Check the boundaries of loops by x, y, u and i.
I will use this algorithm for image rotation, however I realized that it only rotates squares, not rectangles.
Would anyone know why?
Main code-problem:
public static int[] rotate(double angle, int[] pixels, int width, int height) {
final double radians = Math.toRadians(angle);
final double cos = Math.cos(radians);
final double sin = Math.sin(radians);
final int[] pixels2 = new int[pixels.length];
for(int pixel = 0; pixel < pixels2.length; pixel++) {
pixels2[pixel] = 0xFFFFFF;
}
for(int x = 0; x < width; x++) {
for(int y = 0; y < height; y++) {
final int centerx = width / 2;
final int centery = height / 2;
final int m = x - centerx;
final int n = y - centery;
final int j = ((int) ( m * cos + n * sin ) ) + centerx;
final int k = ((int) ( n * cos - m * sin ) ) + centery;
if( j >= 0 && j < width && k >= 0 && k < height ){
pixels2[ ( y * width + x ) ] = pixels[ ( k * width + j ) ];
}
}
}
return pixels2;
}
Context application:
try {
BufferedImage testrot = ImageIO.read(new File("./32x32.png"));
int[] linearpixels = new int[testrot.getWidth() * testrot.getHeight()];
int c = 0;
for(int i = 0; i < testrot.getWidth(); i++){
for(int j = 0; j < testrot.getHeight(); j++){
linearpixels[c] = testrot.getRGB(i, j);
c++;
}
}
int[] lintestrot = rotate(50, linearpixels, 32, 32);
BufferedImage image = new BufferedImage(70, 70, BufferedImage.TYPE_INT_RGB);
c = 0;
for(int i = 0; i < 32; i++){
for(int j = 0; j < 32; j++){
image.setRGB(i, j, lintestrot[c]);
c++;
}
}
File outputfile = new File("test002.bmp");
ImageIO.write(image, "bmp", outputfile);
} catch (IOException e1) {
e1.printStackTrace();
}
If you alter to 33 width or height the result will be wrong (wrong image).
You algorithm actually does work. The problem is with your loops in your context application. Because the pixels are stored in raster order, the outer loop needs to iterate to the height and the inner loop iterates to the width, e.g:
for(int i = 0; i < testrot.getHeight(); i++){
for(int j = 0; j < testrot.getWidth(); j++){
linearpixels[c] = testrot.getRGB(j, i); //edit here, tested
c++;
}
}
Then if you change height to 40 for example:
int[] lintestrot = rotate(50, linearpixels, 32, 40);
The loops need to change like this:
c = 0;
for(int i = 0; i < 40; i++){
for(int j = 0; j < 32; j++){
image.setRGB(i, j, lintestrot[c]);
c++;
}
}
Note that the order is reversed in the loops (height then width) compared to the function call (width then height).
I am trying to rotate image without standard method , making color array and manipulate it, but when I invoke the, rotation I get black points (look the picture)
Here is my code, colScaled is the picture I am trying to convert to an array:
public void arrays() {
colScaled = zoom2();
int j = 0;
int i = 0;
angel = Integer.parseInt(this.mn.jTextField1.getText());
float degree = (float) Math.toRadians(angel);
float cos = (float) Math.cos(degree);
float sin = (float) Math.sin(degree);
int W = Math.round(colScaled[0].length * Math.abs(sin) + colScaled.length * Math.abs(cos));
int H = Math.round(colScaled[0].length * Math.abs(cos) + colScaled.length * Math.abs(sin));
int x;
int y;
int xn = (int) W / 2;
int yn = (int) H / 2;
int hw = (int) colScaled.length / 2;
int hh = (int) colScaled[0].length / 2;
BufferedImage image = new BufferedImage(W + 1, H + 1, im.getType());
for (i = 0; i < colScaled.length; i++) {
for (j = 0; j < colScaled[0].length; j++) {
x = Math.round((i - hw) * cos - (j - hh) * sin + xn);
y = Math.round((i - hw) * sin + (j - hh) * cos + yn);
image.setRGB(x, y, colScaled[i][j]);
}
}
ImageIcon ico = new ImageIcon(image);
this.mn.jLabel1.setIcon(ico);
}
Notice this block in your code :-
for (i = 0; i < colScaled.length; i++) {
for (j = 0; j < colScaled[0].length; j++) {
x = Math.round((i - hw) * cos - (j - hh) * sin + xn);
y = Math.round((i - hw) * sin + (j - hh) * cos + yn);
image.setRGB(x, y, colScaled[i][j]);
}
}
The x and y is pixel coordinate in source image (colScaled).
The objective of this code is to fill all pixels in destination image (image).
In your loop, there is no guarantee that all pixels in the destination image will be filled, even it is in the rectangle zone.
The above image depict the problem.
See? It is possible that the red pixel in the destination image will not be written.
The correct solution is to iterating pixel in destination image, then find a corresponding pixel in source image later.
Edit: After posting, I just saw the Spektre's comment.
I agree, it seems to be a duplicated question. The word "pixel array" made me thing it is not.