Android 图像处理（类型转换，比率缩放，倒影，圆角）

Android 图像处理（类型转换，比例缩放，倒影，圆角）

 

 

/** 
 * 1.放大缩小图片 
 *  
 * @param bitmap 
 * @param w 
 * @param h 
 * @return 
 */  
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 
 *  
 * @param bitmap 
 * @param roundPx 
 * @return 
 */  
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 
 *  
 * @param bitmap 
 * @return 
 */  
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 
 *  
 * @param drawable 
 * @return 
 */  
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;  
}