【Android 界面效果41】Matrix 与 ColorMatrix

Matrix：

简单用法就是直接使用它的setXX（）方法

而高级一点来理解他就是去理解一个线性矩形

首先我们来认识线性矩形：(用画图粗略地画不要见怪)

分析：

那还有一组 MRERSP_0 MRERSP_1是干什么的呢？

等下告诉你

如：选择90度  那九十度就放进去a角里

Float [] x={1.0f,0.0f,0.0f,0.0f,-1.0f,0.0f,0.0f,0.0f,0.0f};

Matrix matrix=new Matrix();

matrix.setValues(f);

也有简单一点的：

matrix.setRotate(90);

 

如果想围绕哪个点：

matrix.setRotate(90,x,y);

matrix.setRotate(90,0,0);

或者：Float [] x={1.0f,0.0f,0.0f,0.0f,-1.0f,0.0f,0.0f,0.0f,0.0f};

而围绕100,100可以这样：如下：

Float [] x={

1.0f,0.0f,100.0f,

0.0f,-1.0f,100.0f,

0.0f,0.0f,0.0f};

现在清楚MRERSP_0 MRERSP_1是干什么的吧？

归根结底是这个图，重点在 a b d e 记好他们的位置  然后套用公式：

X=aX1+bY1;

Y=dX1+eY1;

如：y=-x;

那需要什么条件? 问自己a b d e 怎么设置吧  其他同理

对称效果图：

实例：

//锐化效果
  public static Bitmap toSharp(Bitmap bit)
     { 
         long start =System.currentTimeMillis(); 
         // 拉普拉斯矩阵  
         int[] laplacian = new int[] { -1, -1, -1, -1, 9, -1, -1, -1, -1 }; 
          
         int width = bit.getWidth(); 
         int height = bit.getHeight(); 
         Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.RGB_565); 
          
         int pixR = 0; 
         int pixG = 0; 
         int pixB = 0; 
          
         int pixColor = 0; 
          
         int newR = 0; 
         int newG = 0; 
         int newB = 0; 
          
         int idx = 0; 
         float alpha = 0.3F; 
         int[] pixels = new int[width * height]; 
         bit.getPixels(pixels, 0, width, 0, 0, width, height); 
         for (int i = 1, length = height - 1; i < length; i++) 
         { 
             for (int k = 1, len = width - 1; k < len; k++) 
             { 
                 idx = 0; 
                 for (int m = -1; m <= 1; m++) 
                 { 
                     for (int n = -1; n <= 1; n++) 
                     { 
                         pixColor = pixels[(i + n) * width + k + m]; 
                         pixR = Color.red(pixColor); 
                         pixG = Color.green(pixColor); 
                         pixB = Color.blue(pixColor); 
                          
                         newR = newR + (int) (pixR * laplacian[idx] * alpha); 
                         newG = newG + (int) (pixG * laplacian[idx] * alpha); 
                         newB = newB + (int) (pixB * laplacian[idx] * alpha); 
                         idx++; 
                     } 
                 } 
                  
                 newR = Math.min(255, Math.max(0, newR)); 
                 newG = Math.min(255, Math.max(0, newG)); 
                 newB = Math.min(255, Math.max(0, newB)); 
                  
                 pixels[i * width + k] = Color.argb(255, newR, newG, newB); 
                 newR = 0; 
                 newG = 0; 
                 newB = 0; 
             } 
         } 
          
         bitmap.setPixels(pixels, 0, width, 0, 0, width, height); 
         long end = System.currentTimeMillis(); 
         //Log.d("may", "used time="+(end - start)); 
         return bitmap; 
     }
 
  //旋轉90度
  public static Bitmap ToNinety(Bitmap bitmap){
   int w=bitmap.getWidth();
   int h=bitmap.getHeight();
   float fw=((float)100/w);
   float fh=((float)100/h);
   Canvas canvas=new Canvas(bitmap);
   Matrix matrix=new Matrix();
   Paint paint=new Paint();
   paint.setColor(Color.RED);

方便大家看 我把 数组这样写：

final float jingxiang[]={
     0.0f,1.0f,0.0f,
     -1.0f,0.0f,0.0f,
     0.0f,0.0f,1.0f};
  
  matrix.setValues(jingxiang);
  //matrix.setRotate(90);
  matrix.postScale(fw, fh);
  
  canvas.drawBitmap(bitmap, matrix, paint);
  Bitmap newbitmap = Bitmap.createBitmap(bitmap, 0, 0, w,h, matrix, true);
  return newbitmap;
  }

这里有个要点：并不是每个createBitmap()方法都可以达到你想要的，不同参数效果不一样，我觉得归根结底是哪个true 影响了一切

但有些效果又不用带true参数的createBitmap（）方法

如黑白照片效果：

//把图片变成黑白
 public static Bitmap toGrayscale(Bitmap bmpOriginal) {
  int width, height;
  height = bmpOriginal.getHeight();
  width = bmpOriginal.getWidth();
  Bitmap bmpGrayscale = Bitmap.createBitmap(width, height,
    Bitmap.Config.RGB_565);
  Canvas c = new Canvas(bmpGrayscale);
  Paint paint = new Paint();
  ColorMatrix cm = new ColorMatrix();
  cm.setSaturation(0);
  ColorMatrixColorFilter f = new ColorMatrixColorFilter(cm);
  paint.setColorFilter(f);
  c.drawBitmap(bmpOriginal, 0, 0, paint);
  return bmpGrayscale;
 }

还有图片的变化等效果  想怎样就怎么去计算吧 哈

接下来介绍

ColorMatrix

大家可以把那个有颜色坐标看成一个六面体 每个面都是混合颜色的渐变效果

这个ColorMatrix我犯错就搞了一日了。。虽然很浪费时间 但是却是知道了更多

原理与Matrix 差不多

只是数组变成RGBA

所谓的Red Green Blue Alpha

通常：

1 ,0 ,0, 0, 0,

0 ,1 ,0 ,0 ,0,

0 ,0, 1, 0, 0,

0 ,0 ,0 ,1 ,0

这样就是普通效果

现在可以根据参数来设置自己的效果了

简单例子：

public static Bitmap What(Bitmap bitmap) {
    int w=bitmap.getWidth();
    int h=bitmap.getHeight();
    Bitmap result = Bitmap.createBitmap(w, h,
      Bitmap.Config.RGB_565);
    Canvas c = new Canvas(bmpGrayscale);
    Paint paint = new Paint();
    ColorMatrix cm = new ColorMatrix();
    cm.set(new float[]{
      1 ,0 ,0, 0, 0,

0 ,1 ,0 ,0 ,0,

0 ,0, 1, 0, 0,

0 ,0 ,0 ,1 ,0

});
    ColorMatrixColorFilter f = new ColorMatrixColorFilter(cm);
    paint.setColorFilter(f);
    c.drawBitmap(bitmap, 0, 0, paint);
    return result;   
  }

有一个也挺好玩的就是黑白效果介绍那里

 public static Bitmap toGrayscale(Bitmap bmpOriginal) {
  int width, height;
  height = bmpOriginal.getHeight();
  width = bmpOriginal.getWidth();
  Bitmap bmpGrayscale = Bitmap.createBitmap(width, height,
    Bitmap.Config.RGB_565);
  Canvas c = new Canvas(bmpGrayscale);
  Paint paint = new Paint();
  ColorMatrix cm = new ColorMatrix();
  cm.setSaturation(0);
  ColorMatrixColorFilter f = new ColorMatrixColorFilter(cm);
  paint.setColorFilter(f);
  c.drawBitmap(bmpOriginal, 0, 0, paint);
  return bmpGrayscale;
 }

 

原理：把某东西画到某东西上

 

cm.setSaturation(0); 根据不同参数也有不同效果

更多学习请看androidAPI

其实学习了这个android ==学习了Java==学习了C#

都有这样的东西吧 哈