算法原理:用前一个像素点的RGB值分别减去当前像素点的RGB值并加上127作为当前像素点的RGB值。
例:
ABC
求B点的浮雕效果如下:
B.r = C.r - B.r + 127;
B.g = C.g - B.g + 127;
B.b = C.b - B.b + 127;
注意RGB值在0~255之间。
效果图:
原图 效果图
package com.color; import android.content.Context; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.util.AttributeSet; import android.widget.ImageView; public class ColorView extends ImageView { private Paint myPaint = null; private Bitmap bitmap = null; private int width,height; private int[] oldPixels; private int[] newPixels; private int color,color2; private int pixelsR,pixelsG,pixelsB,pixelsA,pixelsR2,pixelsG2,pixelsB2; public ColorView(Context context, AttributeSet attrs) { super(context, attrs); bitmap = BitmapFactory.decodeResource(context.getResources(),R.drawable.ww); width = bitmap.getWidth(); height = bitmap.getHeight(); oldPixels = new int[width*height]; newPixels = new int[width*height]; invalidate(); } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); //获取像素 bitmap.getPixels(oldPixels, 0, width, 0, 0, width, height); for(int i = 1;i < height*width; i++){ color = oldPixels[i-1]; //前一个像素 pixelsR = Color.red(color); pixelsG = Color.green(color); pixelsB = Color.blue(color); //当前像素 color2 = oldPixels[i]; pixelsR2 = Color.red(color2); pixelsG2 = Color.green(color2); pixelsB2 = Color.blue(color2); pixelsR = (pixelsR - pixelsR2 + 127); pixelsG = (pixelsG - pixelsG2 + 127); pixelsB = (pixelsB - pixelsB2 + 127); //均小于等于255 if(pixelsR > 255){ pixelsR = 255; } if(pixelsG > 255){ pixelsG = 255; } if(pixelsB > 255){ pixelsB = 255; } newPixels[i] = Color.argb(pixelsA, pixelsR, pixelsG, pixelsB); } bitmap.setPixels(newPixels, 0, width, 0, 0, width, height); canvas.drawBitmap(bitmap,0,0,myPaint); } }