我过去用 android 做了一些图像过滤，对于 ThresholdingFilter 我使用了这个代码：
public class ThresholdingFilter {
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ METHODS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/**
* Methods that apply a Thresholding Effect on image
*
* @param imageIn the input image
* @param threshold Integer - value (0-255) prefered value (threshold = 125)
* @return
*/
public static AndroidImage process(AndroidImage imageIn, int threshold) {
// The Resulting image
AndroidImage imageOut;
// Initiate the Output image
imageOut = new AndroidImage(imageIn.getImage());
// Do Threshold process
for(int y=0; y<imageIn.getHeight(); y++){
for(int x=0; x<imageIn.getWidth(); x++){
if(imageOut.getRComponent(x,y) < threshold){
imageOut.setPixelColor(x, y, 0,0,0);
}
else{
imageOut.setPixelColor(x, y, 255,255,255);
}
}
}
// Return final image
return imageOut;
}
}
AndroidImage 是 Android 位图的自定义包装类
public class AndroidImage {
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ATTRIBUTES ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// Original bitmap image
private Bitmap image;
// Format of the image (jpg/png)
private String formatName;
/** Dimensions of image */
// Width of the image
private int width;
// Height of the image
private int height;
// RGB Array Color
protected int[] colorArray;
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ METHODS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/**
* Constructor
*
* @param img the Bitmap from which we create our AndroidImage Object
*/
public AndroidImage(Bitmap img){
this.image = img;
this.formatName = "jpg";
this.width = img.getWidth();
this.height = img.getHeight();
updateColorArray();
}
/**
* Method to reset the image to a solid color
*
* @param color - color to reset the entire image to
*/
public void clearImage(int color){
for(int y=0; y<height; y++){
for(int x=0; x<width; x++){
image.setPixel(x, y, color);
}
}
}
/**
* Method to set color array for image - called on initialization by constructor
*
*
*/
private void updateColorArray(){
colorArray = new int[width * height];
image.getPixels(colorArray, 0, width, 0, 0, width, height);
int r, g, b;
for (int y = 0; y < height; y++){
for (int x = 0; x < width; x++){
int index = y * width + x;
r = (colorArray[index] >> 16) & 0xff;
g = (colorArray[index] >> 8) & 0xff;
b = colorArray[index] & 0xff;
colorArray[index] = 0xff000000 | (r << 16) | (g << 8) | b;
}
}
}
/**
* Method to set the color of a specific pixel
*
* @param x
* @param y
* @param color
*/
public void setPixelColor(int x, int y, int color){
colorArray[((y*image.getWidth()+x))] = color;
image.setPixel(x, y, color);
}
/**
* Method to get the color of a specified pixel
*
* @param x
* @param y
* @return color
*/
public int getPixelColor(int x, int y){
return colorArray[y*width+x];
}
/**
* Method to set the color of a specified pixel from an RGB combination
*
* @param x
* @param y
* @param c0
* @param c1
* @param c2
*/
public void setPixelColor(int x, int y, int c0, int c1, int c2){
colorArray[((y*image.getWidth()+x))] = (255 << 24) + (c0 << 16) + (c1 << 8) + c2;
image.setPixel(x, y, colorArray[((y*image.getWidth()+x))]);
}
/**
* Method to get the RED color of a specified pixel
*
* @param x
* @param y
* @return color of R component
*/
public int getRComponent(int x, int y){
return (getColorArray()[((y*width+x))]& 0x00FF0000) >>> 16;
}
/**
* Method to get the GREEN color of a specified pixel
*
* @param x
* @param y
* @return color of G component
*/
public int getGComponent(int x, int y){
return (getColorArray()[((y*width+x))]& 0x0000FF00) >>> 8;
}
/**
* Method to get the BLUE color of a specified pixel
*
* @param x
* @param y
* @return color of B component
*/
public int getBComponent(int x, int y){
return (getColorArray()[((y*width+x))] & 0x000000FF);
}
/**
* Method to rotate an image by the specified number of degrees
*
* @param rotateDegrees
*/
public void rotate (int rotateDegrees){
Matrix mtx = new Matrix();
mtx.postRotate(rotateDegrees);
image = Bitmap.createBitmap(image, 0, 0, width, height, mtx, true);
width = image.getWidth();
height = image.getHeight();
updateColorArray();
}
// Setters and Getters
/**
* @return the image
*/
public Bitmap getImage() {
return image;
}
/**
* @param image the image to set
*/
public void setImage(Bitmap image) {
this.image = image;
}
/**
* @return the formatName
*/
public String getFormatName() {
return formatName;
}
/**
* @param formatName the formatName to set
*/
public void setFormatName(String formatName) {
this.formatName = formatName;
}
/**
* @return the width
*/
public int getWidth() {
return width;
}
/**
* @param width the width to set
*/
public void setWidth(int width) {
this.width = width;
}
/**
* @return the height
*/
public int getHeight() {
return height;
}
/**
* @param height the height to set
*/
public void setHeight(int height) {
this.height = height;
}
/**
* @return the colorArray
*/
public int[] getColorArray() {
return colorArray;
}
/**
* @param colorArray the colorArray to set
*/
public void setColorArray(int[] colorArray) {
this.colorArray = colorArray;
}
}
希望对你有帮助