Android实现图片高斯模糊，以及图片镜像翻转。

好久没写博客，发现不止手痒，，原来不学习还是会颓废的…..

哎…..

速速找了网上比较感兴趣的功能，，看着前人大神门的方法实现,方便自己也方便别人：

上图：

代码：

MainActivity.class

package com.hero.zhaoq.bitmapdemo;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.renderscript.Allocation;
import android.renderscript.Element;
import android.renderscript.RenderScript;
import android.renderscript.ScriptIntrinsicBlur;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.widget.ImageView;

/**
 * Android实现镜像效果
 */
public class MainActivity extends AppCompatActivity {

    private ImageView imageView1;
    private ImageView imageView2;
    private ImageView imageView3;
    private ImageView imageView4;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initView();
    }

    //
    private void initView() {
        imageView1 = (ImageView) findViewById(R.id.imageView1);
        imageView2 = (ImageView) findViewById(R.id.imageView2);
        imageView3 = (ImageView) findViewById(R.id.imageView3);
        imageView4 = (ImageView) findViewById(R.id.imageView4);

        //获取资源图片
        Bitmap bm =  BitmapFactory.decodeResource(getResources(),R.mipmap.demo);

        //显示原图形
        imageView1.setImageBitmap(bm);

        //处理
        Bitmap modBm = Bitmap.createBitmap(bm.getWidth(),bm.getHeight(),bm.getConfig());

        //处理画布 重新绘制图形 形成镜像
        Canvas canvas = new Canvas(modBm);

        Paint paint = new Paint();
// paint.setColor(Color.BLACK);
// paint.setAntiAlias(true);

        //绘制矩阵 Matrix主要用于对平面进行平移(Translate)，缩放(Scale)，旋转(Rotate)以及斜切(Skew)操作。
        Matrix matrix = new Matrix();
// matrix.setRotate(90,bm.getWidth()/2,bm.getHeight());
// matrix.setTranslate(20,20);
        //镜子效果：
        matrix.setScale(-1,1);//翻转
        matrix.postTranslate(bm.getWidth(),0);

        canvas.drawBitmap(bm,matrix,paint);
        imageView2.setImageBitmap(modBm);


        Bitmap bm2 =  BitmapFactory.decodeResource(getResources(),R.mipmap.demo);
        imageView3.setImageBitmap(blurBitmap(bm2));

        //设置 触摸事件 实现 触摸改变 模糊状态
        imageView3.setOnTouchListener(new View.OnTouchListener() {

            private float mLastY;

            @Override
            public boolean onTouch(View v, MotionEvent event) {
                switch (event.getAction()) {
                    case MotionEvent.ACTION_DOWN:
                        mLastY = event.getY();
                        break;
                    case MotionEvent.ACTION_MOVE:
                        float y = event.getY();
                        float alphaDelt = (y - mLastY) / 1000;
                        float alpha = imageView3.getAlpha() + alphaDelt;
                        if (alpha > 1.0) {
                            alpha = 1.0f;
                        } else if (alpha <0.0) {
                            alpha = 0.0f;
                        }
                        imageView3.setAlpha(alpha);
                        break;
                    case MotionEvent.ACTION_UP:
                        break;
                }
                return true;
            }
        });



        Bitmap bm3 =  BitmapFactory.decodeResource(getResources(),R.mipmap.demo);
        imageView4.setImageBitmap(blurBitmap(bm3));

        //设置 触摸事件 实现 触摸改变 模糊状态
        imageView4.setOnTouchListener(new View.OnTouchListener() {

            private float mLastY;

            @Override
            public boolean onTouch(View v, MotionEvent event) {
                switch (event.getAction()) {
                    case MotionEvent.ACTION_DOWN:
                        mLastY = event.getY();
                        break;
                    case MotionEvent.ACTION_MOVE:
                        float y = event.getY();
                        float alphaDelt = (y - mLastY) / 1000;
                        float alpha = imageView4.getAlpha() + alphaDelt;
                        if (alpha > 1.0) {
                            alpha = 1.0f;
                        } else if (alpha <0.0) {
                            alpha = 0.0f;
                        }
                        imageView4.setAlpha(alpha);
                        break;
                    case MotionEvent.ACTION_UP:
                        break;
                }
                return true;
            }
        });
    }

    //该方法 要求版本最低为 17 API
    public Bitmap blurBitmap(Bitmap bitmap){

        //Let's create an empty bitmap with the same size of the bitmap we want to blur
        Bitmap outBitmap = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Bitmap.Config.ARGB_8888);

        //Instantiate a new Renderscript
        RenderScript rs = RenderScript.create(getApplicationContext());

        //Create an Intrinsic Blur Script using the Renderscript
        ScriptIntrinsicBlur blurScript = ScriptIntrinsicBlur.create(rs, Element.U8_4(rs));

        //Create the Allocations (in/out) with the Renderscript and the in/out bitmaps
        Allocation allIn = Allocation.createFromBitmap(rs, bitmap);
        Allocation allOut = Allocation.createFromBitmap(rs, outBitmap);

        //Set the radius of the blur
        blurScript.setRadius(5.f);

        //Perform the Renderscript
        blurScript.setInput(allIn);
        blurScript.forEach(allOut);

        //Copy the final bitmap created by the out Allocation to the outBitmap
        allOut.copyTo(outBitmap);

        //recycle the original bitmap
        bitmap.recycle();

        //After finishing everything, we destroy the Renderscript.
        rs.destroy();

        return outBitmap;
    }


    //高斯模糊 方法二 效率较低：
    public static Bitmap doBlur(Bitmap sentBitmap, int radius, boolean canReuseInBitmap) {

        // Stack Blur v1.0 from
        // http://www.quasimondo.com/StackBlurForCanvas/StackBlurDemo.html
        //
        // Java Author: Mario Klingemann 
        // http://incubator.quasimondo.com
        // created Feburary 29, 2004
        // Android port : Yahel Bouaziz 
        // http://www.kayenko.com
        // ported april 5th, 2012

        // This is a compromise between Gaussian Blur and Box blur
        // It creates much better looking blurs than Box Blur, but is
        // 7x faster than my Gaussian Blur implementation.
        //
        // I called it Stack Blur because this describes best how this
        // filter works internally: it creates a kind of moving stack
        // of colors whilst scanning through the image. Thereby it
        // just has to add one new block of color to the right side
        // of the stack and remove the leftmost color. The remaining
        // colors on the topmost layer of the stack are either added on
        // or reduced by one, depending on if they are on the right or
        // on the left side of the stack.
        //
        // If you are using this algorithm in your code please add
        // the following line:
        //
        // Stack Blur Algorithm by Mario Klingemann 

        Bitmap bitmap;
        if (canReuseInBitmap) {
            bitmap = sentBitmap;
        } else {
            bitmap = sentBitmap.copy(sentBitmap.getConfig(), true);
        }

        if (radius <1) {
            return (null);
        }

        int w = bitmap.getWidth();
        int h = bitmap.getHeight();

        int[] pix = new int[w * h];
        bitmap.getPixels(pix, 0, w, 0, 0, w, h);

        int wm = w - 1;
        int hm = h - 1;
        int wh = w * h;
        int div = radius + radius + 1;

        int r[] = new int[wh];
        int g[] = new int[wh];
        int b[] = new int[wh];
        int rsum, gsum, bsum, x, y, i, p, yp, yi, yw;
        int vmin[] = new int[Math.max(w, h)];

        int divsum = (div + 1) >> 1;
        divsum *= divsum;
        int dv[] = new int[256 * divsum];
        for (i = 0; i <256 * divsum; i++) {
            dv[i] = (i / divsum);
        }

        yw = yi = 0;

        int[][] stack = new int[div][3];
        int stackpointer;
        int stackstart;
        int[] sir;
        int rbs;
        int r1 = radius + 1;
        int routsum, goutsum, boutsum;
        int rinsum, ginsum, binsum;

        for (y = 0; y             rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;
            for (i = -radius; i <= radius; i++) {
                p = pix[yi + Math.min(wm, Math.max(i, 0))];
                sir = stack[i + radius];
                sir[0] = (p & 0xff0000) >> 16;
                sir[1] = (p & 0x00ff00) >> 8;
                sir[2] = (p & 0x0000ff);
                rbs = r1 - Math.abs(i);
                rsum += sir[0] * rbs;
                gsum += sir[1] * rbs;
                bsum += sir[2] * rbs;
                if (i > 0) {
                    rinsum += sir[0];
                    ginsum += sir[1];
                    binsum += sir[2];
                } else {
                    routsum += sir[0];
                    goutsum += sir[1];
                    boutsum += sir[2];
                }
            }
            stackpointer = radius;

            for (x = 0; x 
                r[yi] = dv[rsum];
                g[yi] = dv[gsum];
                b[yi] = dv[bsum];

                rsum -= routsum;
                gsum -= goutsum;
                bsum -= boutsum;

                stackstart = stackpointer - radius + div;
                sir = stack[stackstart % div];

                routsum -= sir[0];
                goutsum -= sir[1];
                boutsum -= sir[2];

                if (y == 0) {
                    vmin[x] = Math.min(x + radius + 1, wm);
                }
                p = pix[yw + vmin[x]];

                sir[0] = (p & 0xff0000) >> 16;
                sir[1] = (p & 0x00ff00) >> 8;
                sir[2] = (p & 0x0000ff);

                rinsum += sir[0];
                ginsum += sir[1];
                binsum += sir[2];

                rsum += rinsum;
                gsum += ginsum;
                bsum += binsum;

                stackpointer = (stackpointer + 1) % div;
                sir = stack[(stackpointer) % div];

                routsum += sir[0];
                goutsum += sir[1];
                boutsum += sir[2];

                rinsum -= sir[0];
                ginsum -= sir[1];
                binsum -= sir[2];

                yi++;
            }
            yw += w;
        }
        for (x = 0; x             rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;
            yp = -radius * w;
            for (i = -radius; i <= radius; i++) {
                yi = Math.max(0, yp) + x;

                sir = stack[i + radius];

                sir[0] = r[yi];
                sir[1] = g[yi];
                sir[2] = b[yi];

                rbs = r1 - Math.abs(i);

                rsum += r[yi] * rbs;
                gsum += g[yi] * rbs;
                bsum += b[yi] * rbs;

                if (i > 0) {
                    rinsum += sir[0];
                    ginsum += sir[1];
                    binsum += sir[2];
                } else {
                    routsum += sir[0];
                    goutsum += sir[1];
                    boutsum += sir[2];
                }

                if (i                     yp += w;
                }
            }
            yi = x;
            stackpointer = radius;
            for (y = 0; y                 // Preserve alpha channel: ( 0xff000000 & pix[yi] )
                pix[yi] = (0xff000000 & pix[yi]) | (dv[rsum] <<16) | (dv[gsum] <<8) | dv[bsum];

                rsum -= routsum;
                gsum -= goutsum;
                bsum -= boutsum;

                stackstart = stackpointer - radius + div;
                sir = stack[stackstart % div];

                routsum -= sir[0];
                goutsum -= sir[1];
                boutsum -= sir[2];

                if (x == 0) {
                    vmin[y] = Math.min(y + r1, hm) * w;
                }
                p = x + vmin[y];

                sir[0] = r[p];
                sir[1] = g[p];
                sir[2] = b[p];

                rinsum += sir[0];
                ginsum += sir[1];
                binsum += sir[2];

                rsum += rinsum;
                gsum += ginsum;
                bsum += binsum;

                stackpointer = (stackpointer + 1) % div;
                sir = stack[stackpointer];

                routsum += sir[0];
                goutsum += sir[1];
                boutsum += sir[2];

                rinsum -= sir[0];
                ginsum -= sir[1];
                binsum -= sir[2];

                yi += w;
            }
        }

        bitmap.setPixels(pix, 0, w, 0, 0, w, h);

        return (bitmap);
    }
}

github源码：https://github.com/229457269/BitmapDemo