本博客主要作为作者自己的笔记,学习自http://www.jianshu.com/p/7ae7dfe47a70
网上实现毛玻璃效果大致分为两种,一种是java实现,一种是c实现。一般来说,java实现效率没有c实现效率高,本次使用的是复制过来的java代码,效果参考http://www.quasimondo.com/StackBlurForCanvas/StackBlurDemo.html。
如果图片非常大,那么处理的时间就会比较长,影响用户体验,所以可以先将图片缩小在模糊化,效果也会更加明显。
本人学习效果:
原图
缩放倍率2 模糊程度10
缩放倍率2 模糊程度20
缩放倍率2 模糊程度50
缩放倍率8 模糊程度20
为了使用方便,重新对其进行封装,代码如下
package com.example.photoblurdemo.utils;
import android.graphics.Bitmap;
import android.os.Build;
import android.util.Log;
/**
* 类说明:处理bitmap,使bitmap模糊化(毛玻璃效果)
* created by liuxiong on 2017/1/12
**/
public class BlurBitmapUtils {
/**
* 方法说明: 先将图片进行缩放处理,再对图片进行毛玻璃效果处理
* @param scaleRatio 缩放倍率
* @param blurRadius 模糊程度
* @param bitmap 资源图片
*@author liuxiong
*@time 2017/1/12 11:26
*/
public static Bitmap blurBitmap(int scaleRatio,int blurRadius,Bitmap bitmap){
if(bitmap==null){
return null;
}
if(scaleRatio<2){ //缩放比例小于2会崩
scaleRatio=2;
}
if(blurRadius<1){
blurRadius=1;
}
Bitmap scaledBitmap = Bitmap.createScaledBitmap(
bitmap,
bitmap.getWidth()/ scaleRatio,
bitmap.getHeight()/ scaleRatio,
false
); //毛玻璃边缘有没有锯齿都没关系,所以设为false
return bitmap = doBlur(scaledBitmap, blurRadius, true);
}
/**
* 方法说明: 先将图片进行缩放处理,使图片小于maxSize时,再对图片进行毛玻璃效果处理
* @param bitmap 资源图片
* @param blurRadius 模糊程度
* @param maxSize 图片最大的内存大小
*@author liuxiong
*@time 2017/1/12 11:31
*/
public static Bitmap blurBitmap(Bitmap bitmap,int blurRadius,int maxSize){
if(bitmap==null){
return null;
}
if(blurRadius<0){
blurRadius=0;
}
if(maxSize<50*1024){
maxSize=50*1024;
}
long size = getBitmapsize(bitmap);
Log.d("----","-----size="+size);
int scaleRatio=1;
if(size>maxSize){
scaleRatio= (int) ((float)size/maxSize+0.5);
}
return blurBitmap(scaleRatio,blurRadius,bitmap);
}
/**
* 方法说明: 获取bitmap的大小
* @param bitmap 资源图片
*@author liuxiong
*@time 2017/1/12 11:35
*/
public static long getBitmapsize(Bitmap bitmap){
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR1) {
return bitmap.getByteCount();
}
// Pre HC-MR1
return bitmap.getRowBytes() * bitmap.getHeight();
}
/**
* 方法说明: 将图片进行毛玻璃效果处理(java算法)
* @param sentBitmap 资源图片
* @param radius 模糊程度
* @param canReuseInBitmap 是否重用
*@author liuxiong
*@time 2017/1/12 11:23
*/
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 < h; 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 < w; 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 < w; 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 < hm) {
yp += w;
}
}
yi = x;
stackpointer = radius;
for (y = 0; y < h; 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);
Log.d("-----","-----size="+getBitmapsize(bitmap));
return (bitmap);
}
}
缩放比例小于2好像会造成崩溃,本人菜鸟没找到原因,activity代码如下
package com.example.photoblurdemo;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.EditText;
import android.widget.ImageView;
import com.example.photoblurdemo.utils.BlurBitmapUtils;
import java.io.InputStream;
public class MainActivity extends AppCompatActivity {
private ImageView mIv;
private EditText mEtRadius;
private EditText mEdRatio;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mIv = (ImageView) findViewById(R.id.iv_photo);
mEdRatio = (EditText) findViewById(R.id.et_scale_ratio);
mEtRadius = (EditText) findViewById(R.id.et_blur_radius);
}
public void onClick(View view){
String ratio = mEdRatio.getText().toString().trim();
String radius = mEtRadius.getText().toString().trim();
if(TextUtils.isEmpty(ratio)){
ratio="0";
}
if(TextUtils.isEmpty(radius)){
radius="0";
}
Resources r = getResources();
InputStream is = r.openRawResource(R.drawable.beauty_girls);
BitmapDrawable bmpDraw = new BitmapDrawable(is);
Bitmap bmp = bmpDraw.getBitmap();
// bmp= BlurBitmapUtils.blurBitmap(1, 8, bmp);
// bmp= BlurBitmapUtils.blurBitmap(bmp,Integer.parseInt(ratio),100*1024);
bmp= BlurBitmapUtils.blurBitmap(Integer.valueOf(ratio),Integer.valueOf(radius),bmp);
mIv.setImageBitmap(bmp);
}
}