我想在Java中使用fisheye lens algorithm，但我无法实现主方法。
在this site的底部，我找到了实现鱼眼算法的java代码，但是没有任何main（）方法。我试图用自己的方法实现一个main（）方法，但到目前为止我只能显示图像，但我不能在该图像上使用barrel（）方法，这会对我的图像产生鱼眼效果。
你能否修正我的主要方法，或者实现一个新方法，加载一些图像（bufferedImage）然后在该图像上使用barrel（）方法？
到目前为止我的代码是：
import java.awt.FlowLayout;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
public class DisplayImage {
float xscale;
float yscale;
float xshift;
float yshift;
int [] s;
public BufferedImage barrel (BufferedImage input, float k){
float centerX=input.getWidth()/2; //center of distortion
float centerY=input.getHeight()/2;
int width = input.getWidth(); //image bounds
int height = input.getHeight();
BufferedImage dst = new BufferedImage(width, height,BufferedImage.TYPE_INT_ARGB); //output pic
xshift = calc_shift(0,centerX-1,centerX,k);
float newcenterX = width-centerX;
float xshift_2 = calc_shift(0,newcenterX-1,newcenterX,k);
yshift = calc_shift(0,centerY-1,centerY,k);
float newcenterY = height-centerY;
float yshift_2 = calc_shift(0,newcenterY-1,newcenterY,k);
xscale = (width-xshift-xshift_2)/width;
yscale = (height-yshift-yshift_2)/height;
for(int j=0;j<dst.getHeight();j++){
for(int i=0;i<dst.getWidth();i++){
float x = getRadialX((float)i,(float)j,centerX,centerY,k);
float y = getRadialY((float)i,(float)j,centerX,centerY,k);
sampleImage(input,x,y);
int color = ((s[1]&0x0ff)<<16)|((s[2]&0x0ff)<<8)|(s[3]&0x0ff);
// System.out.print(i+" "+j+" \\");
dst.setRGB(i, j, color);
}
}
return dst;
}
void sampleImage(BufferedImage arr, float idx0, float idx1)
{
s = new int [4];
if(idx0<0 || idx1<0 || idx0>(arr.getHeight()-1) || idx1>(arr.getWidth()-1)){
s[0]=0;
s[1]=0;
s[2]=0;
s[3]=0;
return;
}
float idx0_fl=(float) Math.floor(idx0);
float idx0_cl=(float) Math.ceil(idx0);
float idx1_fl=(float) Math.floor(idx1);
float idx1_cl=(float) Math.ceil(idx1);
int [] s1 = getARGB(arr,(int)idx0_fl,(int)idx1_fl);
int [] s2 = getARGB(arr,(int)idx0_fl,(int)idx1_cl);
int [] s3 = getARGB(arr,(int)idx0_cl,(int)idx1_cl);
int [] s4 = getARGB(arr,(int)idx0_cl,(int)idx1_fl);
float x = idx0 - idx0_fl;
float y = idx1 - idx1_fl;
s[0]= (int) (s1[0]*(1-x)*(1-y) + s2[0]*(1-x)*y + s3[0]*x*y + s4[0]*x*(1-y));
s[1]= (int) (s1[1]*(1-x)*(1-y) + s2[1]*(1-x)*y + s3[1]*x*y + s4[1]*x*(1-y));
s[2]= (int) (s1[2]*(1-x)*(1-y) + s2[2]*(1-x)*y + s3[2]*x*y + s4[2]*x*(1-y));
s[3]= (int) (s1[3]*(1-x)*(1-y) + s2[3]*(1-x)*y + s3[3]*x*y + s4[3]*x*(1-y));
}
int [] getARGB(BufferedImage buf,int x, int y){
int rgb = buf.getRGB(x, y); // Returns by default ARGB.
int [] scalar = new int[4];
scalar[0] = (rgb >>> 24) & 0xFF;
scalar[1] = (rgb >>> 16) & 0xFF;
scalar[2] = (rgb >>> 8) & 0xFF;
scalar[3] = (rgb >>> 0) & 0xFF;
return scalar;
}
float getRadialX(float x,float y,float cx,float cy,float k){
x = (x*xscale+xshift);
y = (y*yscale+yshift);
float res = x+((x-cx)*k*((x-cx)*(x-cx)+(y-cy)*(y-cy)));
return res;
}
float getRadialY(float x,float y,float cx,float cy,float k){
x = (x*xscale+xshift);
y = (y*yscale+yshift);
float res = y+((y-cy)*k*((x-cx)*(x-cx)+(y-cy)*(y-cy)));
return res;
}
float thresh = 1;
float calc_shift(float x1,float x2,float cx,float k){
float x3 = (float)(x1+(x2-x1)*0.5);
float res1 = x1+((x1-cx)*k*((x1-cx)*(x1-cx)));
float res3 = x3+((x3-cx)*k*((x3-cx)*(x3-cx)));
if(res1>-thresh && res1 < thresh)
return x1;
if(res3<0){
return calc_shift(x3,x2,cx,k);
}
else{
return calc_shift(x1,x3,cx,k);
}
}
public static void main(String avg[]) throws IOException
{
BufferedImage img=ImageIO.read(new File("image.jpg"));
ImageIcon icon=new ImageIcon(img);
JFrame frame=new JFrame();
frame.setLayout(new FlowLayout());
frame.setSize(625,648);
JLabel lbl=new JLabel();
lbl.setIcon(icon);
frame.add(lbl);
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
代码正在运行，但它只显示图像。我想在我的图像上使用barrel（）方法，这将产生鱼眼效果。因为我是java的新手，我不能这样做，请帮忙。
答案 0 :(得分：1)
请参阅此网站：
http://popscan.blogspot.in/2012/04/fisheye-lens-equation-simple-fisheye.html
它包含了本文末尾的概念和工作源。
答案 1 :(得分：1)
让你的功能静止
public static BufferedImage barrel (BufferedImage input, float k)
并更改
public static void main(String avg[]) throws IOException
{
BufferedImage img=ImageIO.read(new File("image.jpg"));
//now pass this image to your barrel method and return in new image
//note that, method can be called now without instatntiating any object, as it is static now
BufferImage barrelImage = barrel(img,2.0);
ImageIcon icon=new ImageIcon(barrelImage);
...
...
}
答案 2 :(得分：0)
所以我终于实现了所需的鱼眼！仅仅因为this和this网站。对于有类似问题的人，我在这里给的是非常混乱但工作的代码：
package fisheye;
import java.awt.image.BufferedImage;
import java.awt.image.WritableRaster;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
public class DitherMain {
static String imageString = "image.bmp";
BufferedImage startImage, endImage;
int[] startPixels, endPixels, imR, imG, imB;
int width, height;
public static void main(String[] args){
new DitherMain(loadImage(imageString));
}
//this object transforms the old image and writes the new image
DitherMain(BufferedImage img){
//filing the image into startpixels
startImage = img;
width = img.getWidth();
height = img.getHeight();
startPixels = new int[width*height];
img.getRGB(0, 0, width, height, startPixels, 0, width);
endPixels = fisheye(startPixels, width, height);
transformPixels();
WritableRaster wRaster = endImage.getData().createCompatibleWritableRaster();
wRaster.setSamples(0, 0, width, height, 0, imR);
wRaster.setSamples(0, 0, width, height, 1, imG);
wRaster.setSamples(0, 0, width, height, 2, imB);
endImage.setData(wRaster);
System.out.println(endImage);
//writing the file for endImage into the harddrive
writeFile();
}
void transformPixels(){
//endPixels = startPixels;
endImage = startImage;
imR = new int[endPixels.length];
imG = new int[endPixels.length];
imB = new int[endPixels.length];
for(int i = 0; i < endPixels.length; i++){
imR[i] = (endPixels[i] >> 16) & 0x000000FF;
imG[i] = (endPixels[i] >> 8) & 0x000000FF;
imB[i] = endPixels[i] & 0x000000FF;
}
}
void writeFile(){
try {
ImageIO.write(endImage,"BMP",new File("RESULT.bmp"));
} catch (IOException e) {
e.printStackTrace();
}
}
//this method just loads a specific buffered image
public static BufferedImage loadImage(String fileName){
BufferedImage img;
try{
img=ImageIO.read(new File("image.bmp"));
//img = ImageIO.read(DitherMain.class.getResource(fileName));
} catch (Exception e) {
e.printStackTrace();
throw new RuntimeException(e);
}
return img;
}
public static int[] fisheye(int[] srcpixels, double w, double h) {
/*
* Fish eye effect
* tejopa, 2012-04-29
* http://popscan.blogspot.com
* http://www.eemeli.de
*/
// create the result data
int[] dstpixels = new int[(int)(w*h)];
// for each row
for (int y=0;y<h;y++) {
// normalize y coordinate to -1 ... 1
double ny = ((2*y)/h)-1;
// pre calculate ny*ny
double ny2 = ny*ny;
// for each column
for (int x=0;x<w;x++) {
// normalize x coordinate to -1 ... 1
double nx = ((2*x)/w)-1;
// pre calculate nx*nx
double nx2 = nx*nx;
// calculate distance from center (0,0)
// this will include circle or ellipse shape portion
// of the image, depending on image dimensions
// you can experiment with images with different dimensions
double r = Math.sqrt(nx2+ny2);
// discard pixels outside from circle!
if (0.0<=r&&r<=1.0) {
double nr = Math.sqrt(1.0-r*r);
// new distance is between 0 ... 1
nr = (r + (1.0-nr)) / 2.0;
// discard radius greater than 1.0
if (nr<=1.0) {
// calculate the angle for polar coordinates
double theta = Math.atan2(ny,nx);
// calculate new x position with new distance in same angle
double nxn = nr*Math.cos(theta);
// calculate new y position with new distance in same angle
double nyn = nr*Math.sin(theta);
// map from -1 ... 1 to image coordinates
int x2 = (int)(((nxn+1)*w)/2.0);
// map from -1 ... 1 to image coordinates
int y2 = (int)(((nyn+1)*h)/2.0);
// find (x2,y2) position from source pixels
int srcpos = (int)(y2*w+x2);
// make sure that position stays within arrays
if (srcpos>=0 & srcpos < w*h) {
// get new pixel (x2,y2) and put it to target array at (x,y)
dstpixels[(int)(y*w+x)] = srcpixels[srcpos];
}
}
}
}
}
//return result pixels
return dstpixels;
}
}