Android磨砂图片处理（FastBlur）
常用的图片有png和jpg这2种，这里也只针对这2种图片做简单介绍。项目中使用的网络请求主要是XUtils3，但是对jpg格式图片，磨砂处理有个问题，针对解决办法，下面会有详细说明：
关于XUtils3在Android Studio中的使用：
http://blog.csdn.net/u014620028/article/details/51063377先看效果图：
第一张：
第二张：
说明：
1、每张图中，上面的2张，都是png图片。下面2张，都是jpg图片
2、 左下角的jpg图片，都是用的下面的第一种处理方法；右下角的jpg图片，都是用的下面的第二种处理方法
3、 左上角的png图片，都是用的下面的第一种处理方法；右上角的png图片，都是用的下面的第二种处理方法
4、第一次加载的时候，用XUtils3得到网络jpg图片，然后进行磨砂处理，就会出现图一种右下角的情况。但是，退出去，然后清理缓存，再次进入，就没问题了。即：只要从第二次开始，就会一直正常。但是使用第一种处理方式，一直正常
使用下面说的第一种获取bitmap方法，获取到后，再进行磨砂处理，就不会出现上面效果图中的问题了
代码：
对图片进行磨砂处理的代码：（2种处理方法，我用的第二种，这2种方法效果一样）
package com.chen.bitmapdemo;
import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Build;
import android.renderscript.Allocation;
import android.renderscript.Element;
import android.renderscript.RenderScript;
import android.renderscript.ScriptIntrinsicBlur;
public class FastBlur {
/**
* Android api 17实现的虚化
* 某些机型上可能会Crash
*
* @param context
* @param sentBitmap
* @param radius 大于1小于等于25
* @return
*/
@SuppressLint("NewApi")
public static Bitmap fastblur(Context context, Bitmap sentBitmap, int radius) {
if (sentBitmap == null) {
return null;
}
if (Build.VERSION.SDK_INT > 16) {
Bitmap bitmap = sentBitmap.copy(sentBitmap.getConfig(), true);
final RenderScript rs = RenderScript.create(context);
final Allocation input = Allocation.createFromBitmap(rs,
sentBitmap, Allocation.MipmapControl.MIPMAP_NONE,
Allocation.USAGE_SCRIPT);
final Allocation output = Allocation.createTyped(rs,
input.getType());
final ScriptIntrinsicBlur script = ScriptIntrinsicBlur.create(rs,
Element.U8_4(rs));
script.setRadius(radius /* e.g. 3.f */);
script.setInput(input);
script.forEach(output);
output.copyTo(bitmap);
return bitmap;
}
return stackblur(context, sentBitmap, radius);
}
/**
* 纯Java实现的虚化，适用老版本api，外部只需调上面的fastblur方法，会自动判断
*
* @param context
* @param sentBitmap
* @param radius
* @return
*/
private static Bitmap stackblur(Context context, Bitmap sentBitmap, int radius) {
try {
Bitmap bitmap = null;
try {
bitmap = sentBitmap.copy(sentBitmap.getConfig(), true);
} catch (OutOfMemoryError e) {
e.printStackTrace();
return sentBitmap;
}
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);
return (bitmap);
} catch (Exception e) {
return BitmapFactory.decodeResource(context.getResources(), R.mipmap.ic_launcher);
}
}
/**
* 图片缩放比例
*/
private static final float BITMAP_SCALE = 0.4F;
/**
* 最大模糊度（在0-25之间），值越大，越模糊
*/
private static final float BLUR_RADIUS = 23F;
/**
* 模糊图片的具体算法
*
* @param context 上下文对象
* @param image 需要模糊的图片
* @return 模糊处理后的图片
*/
public static Bitmap blur(Context context, Bitmap image) {
try {
//计算图片缩小后的长度
int width = Math.round(image.getWidth() * BITMAP_SCALE);
int height = Math.round(image.getHeight() * BITMAP_SCALE);
//将缩小后的图片做为预渲染图片
Bitmap inputBitmap = Bitmap.createScaledBitmap(image, width, height, false);
//创建一张渲染后的输出图片
Bitmap outputBitmap = Bitmap.createBitmap(inputBitmap);
//创建RenderScript内核对象
RenderScript rs = RenderScript.create(context);
//创建一个模糊效果的RenderScript的工具对象
ScriptIntrinsicBlur blurScript = ScriptIntrinsicBlur.create(rs, Element.U8_4(rs));
//由于RenderScript并没有使用VM来分配内存
//所以需要使用Allocation类来创建和分配内容空间
//创建Allocation对象的时候其实内存是空的，需要使用copyTo（）将数据填充进去
Allocation tmpIn = Allocation.createFromBitmap(rs, inputBitmap);
Allocation tmpOut = Allocation.createFromBitmap(rs, outputBitmap);
//设置渲染的模糊程度，25f是最大模糊层
blurScript.setRadius(BLUR_RADIUS);
//设置blurScript对象的输入内存
blurScript.setInput(tmpIn);
//将输出数据保存到输出内存中
blurScript.forEach(tmpOut);
//将数据填充到Allocation中
tmpOut.copyTo(outputBitmap);
return outputBitmap;
} catch (Exception e) {
e.printStackTrace();
return image;
} catch (OutOfMemoryError error) {
return image;
}
}
}
要将图片进行磨砂处理，先要拿到bitmap，获取bitmap的2中方法：
1、
private void getImgBitmap(String path) {
new AsyncTask() {
@Override
protected Bitmap doInBackground(String... params) {
URL url = null;
try {
url = new URL(params[0]);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setConnectTimeout(5000);
conn.setRequestMethod("GET");
Log.e("chen", "图片请求状态码=====" + conn.getResponseCode());
if (conn.getResponseCode() == 200) {
InputStream inStream = conn.getInputStream();
Bitmap bitmap = BitmapFactory.decodeStream(inStream);
return bitmap;
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (ProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(Bitmap bitmap) {
if (bitmap == null) {
bitmap = BitmapFactory.decodeResource(getResources(), R.mipmap.default_iv);
}
bitmap = FastBlur.blur(MainActivity.this, bitmap);
if (bitmap != null)
show_iv_png_1.setImageBitmap(bitmap);
else
show_iv_png_1.setImageBitmap(BitmapFactory.decodeResource(getResources(), R.mipmap.default_iv));
}
}.execute(path);
} 第2种方法：
private void getLoadBitmap(String iconUrl) {
if (Util.checkStringIsEmpty(iconUrl)) {
show_iv_png_2.setBackgroundResource(R.mipmap.default_iv);
} else {
ImageOptions imageOptions = new ImageOptions.Builder()
.setImageScaleType(ImageView.ScaleType.FIT_XY)
.setFailureDrawableId(R.mipmap.default_iv)
.setCrop(true)
.setUseMemCache(true)
.build();
x.image().loadDrawable(iconUrl, imageOptions, new Callback.CommonCallback() {
@Override
public void onSuccess(Drawable result) {
Log.e("下载==png==", "onSuccess");
BitmapDrawable bd = (BitmapDrawable) result;
bitmap_png = bd.getBitmap();
// Bitmap cirBitMap = UIUtils.createCircleImage(bg_bitmap, 0);
show_iv_png_2.setImageBitmap(FastBlur.blur(MainActivity.this, bitmap_png));
}
@Override
public void onError(Throwable ex, boolean isOnCallback) {
Log.e("下载==png==", "onError");
show_iv_png_2.setImageResource(R.mipmap.default_iv);
}
@Override
public void onCancelled(CancelledException cex) {
}
@Override
public void onFinished() {
}
});
}
}