Android图像处理（类型转换，比例缩放，倒影，圆角）

Java代码
/**
* 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 dea易做图tPaint = new Paint();
    canvas
            .drawRect(0, height, width, height + reflectionGap,
                    dea易做图tPaint);
    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;
}

作者“xSTARx”

补充：移动开发 , Android ,