Android 图像处理(类型转换,比例缩放,倒影,圆角)的小例子

类型转换图像处理 Android 2022-06-06 10:06:44 562人浏览八月长安

摘要

1.放大缩小图片代码如下:public static Bitmap zoomBitmap(Bitmap bitmap,int w,int h){ &n

1.放大缩小图片

代码如下:
public static Bitmap zoomBitmap(Bitmap bitmap,int w,int h){
        int width = bitmap.getWidth();
        int height = bitmap.getHeight();
        Matrix matrix = new Matrix();
        float scaleWidht = ((float)w / width);
        float scaleHeight = ((float)h / height);
        matrix.postScale(scaleWidht, scaleHeight);
        Bitmap newbmp = Bitmap.createBitmap(bitmap, 0, 0, width, height, matrix, true);
        return newbmp;
    }

2.获得圆角图片的方法

代码如下:
public static Bitmap getRoundedCornerBitmap(Bitmap bitmap,float roundPx){
        Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Config.ARGB_8888);
        canvas canvas = new Canvas(output);
        final int color = 0xff424242;
        final Paint paint = new Paint();
        final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
        final RectF rectF = new RectF(rect);
        paint.setAntiAlias(true);
        canvas.drawARGB(0, 0, 0, 0);
        paint.setColor(color);
        canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
        paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
        canvas.drawBitmap(bitmap, rect, rect, paint);
        return output;
    }

3.获得带倒影的图片方法

代码如下:
public static Bitmap createReflectionImageWithOrigin(Bitmap bitmap){
       final int reflectionGap = 4;
       int width = bitmap.getWidth();
       int height = bitmap.getHeight();
       Matrix matrix = new Matrix();
       matrix.preScale(1, -1);
       Bitmap reflectionImage = Bitmap.createBitmap(bitmap,0, height/2, width, height/2, matrix, false);
       Bitmap bitmapWithReflection = Bitmap.createBitmap(width, (height + height/2), Config.ARGB_8888);
       Canvas canvas = new Canvas(bitmapWithReflection);
       canvas.drawBitmap(bitmap, 0, 0, null);
       Paint deafalutPaint = new Paint();
       canvas.drawRect(0, height,width,height + reflectionGap, deafalutPaint);
       canvas.drawBitmap(reflectionImage, 0, height + reflectionGap, null);
       Paint paint = new Paint();
       LinearGradient shader = new LinearGradient(0, bitmap.getHeight(), 0,
　　　　 bitmapWithReflection.getHeight() + reflectionGap, 0x70ffffff, 0x00ffffff, TileMode.CLAMP);
        paint.setShader(shader);
        // Set the Transfer mode to be porter duff and destination in
        paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN));
        // Draw a rectangle using the paint with our linear gradient
        canvas.drawRect(0, height, width, bitmapWithReflection.getHeight()
                + reflectionGap, paint);
        return bitmapWithReflection;
    }

4.将Drawable转化为Bitmap

代码如下:
public static Bitmap drawableToBitmap(Drawable drawable){
      int width = drawable.getIntrinsicWidth();
      int height = drawable.getIntrinsicHeight();
      Bitmap bitmap = Bitmap.createBitmap(width, height,
      drawable.getOpacity() != PixelFORMat.OPAQUE ? Bitmap.Config.ARGB_8888: Bitmap.Config.RGB_565);
      Canvas canvas = new Canvas(bitmap);
      drawable.setBounds(0,0,width,height);
      drawable.draw(canvas);
      return bitmap;
}