Android ImageUtils 图片工具类，包括：小米从相册调图像空指针，三星旋转照片，压缩图片，保存Bitmap到本地，获取本地视频的缩略图，毛化玻璃效果，代码以后会更新

package com.snyj.wsd.kangaibang.utils;

import android.content.ContentResolver;
import android.content.Context;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.Matrix;
import android.media.ExifInterface;
import android.net.Uri;
import android.provider.MediaStore.Images;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

/**
* Created by ruin on 2016/11/15.
*/
public class ImageUtils {
//小米手机从相册调图空指针问题
public static Uri getPictureUri(android.content.Intent intent, Context context) {
Uri uri = intent.getData();
String type = intent.getType();
if (uri.getScheme().equals("file") && (type.contains("image/"))) {
String path = uri.getEncodedPath();
if (path != null) {
path = Uri.decode(path);
ContentResolver cr = context.getContentResolver();
StringBuffer buff = new StringBuffer();
buff.append("(").append(Images.ImageColumns.DATA).append("=")
.append("'" + path + "'").append(")");
Cursor cur = cr.query(Images.Media.EXTERNAL_CONTENT_URI,
new String[]{Images.ImageColumns._ID},
buff.toString(), null, null);
int index = 0;
for (cur.moveToFirst(); !cur.isAfterLast(); cur.moveToNext()) {
index = cur.getColumnIndex(Images.ImageColumns._ID);
// set _id value
index = cur.getInt(index);
}
if (index == 0) {
// do nothing
} else {
Uri uri_temp = Uri
.parse("content://media/external/images/media/"
+ index);
if (uri_temp != null) {
uri = uri_temp;
}
}
}
}
return uri;
}

/**
* 旋转照片
*
* @param img
* @param degree
* @return
*/
public static Bitmap toturn(Bitmap img, int degree) {
Matrix matrix = new Matrix();
matrix.postRotate(degree); /*翻转90度*/
int width = img.getWidth();
int height = img.getHeight();
img = Bitmap.createBitmap(img, 0, 0, width, height, matrix, true);
return img;
}

/**
* 读取照片exif信息中的旋转角度
*
* @param path 照片路径
* @return角度
*/
public static int readPictureDegree(String path) {
int degree = 0;
try {
ExifInterface exifInterface = new ExifInterface(path);
int orientation = exifInterface.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL);
switch (orientation) {
case ExifInterface.ORIENTATION_ROTATE_90:
degree = 90;
break;
case ExifInterface.ORIENTATION_ROTATE_180:
degree = 180;
break;
case ExifInterface.ORIENTATION_ROTATE_270:
degree = 270;
break;
}
} catch (IOException e) {
e.printStackTrace();
}
return degree;
}

//缩小图片
public static Bitmap smallImage(Bitmap bitmapOrg) {
//获取这个图片的宽和高
int width = bitmapOrg.getWidth();
int height = bitmapOrg.getHeight();

//定义预转换成的图片的宽度和高度
int newWidth = 1200;
//        int newHeight = 960;

//计算缩放率，新尺寸除原始尺寸
float scaleWidth = ((float) newWidth) / width;
//        float scaleHeight = ((float) newHeight) / height;

// 创建操作图片用的matrix对象
Matrix matrix = new Matrix();

// 缩放图片动作
matrix.postScale(scaleWidth, scaleWidth);

// 创建新的图片
Bitmap resizedBitmap = Bitmap.createBitmap(bitmapOrg, 0, 0,
width, height, matrix, true);

//将上面创建的Bitmap转换成Drawable对象，使得其可以使用在ImageView, ImageButton中

return resizedBitmap;
}

//保存Bitmap到本地
public static void saveBitmap(Bitmap bm, String path) {
File f = new File(path);
if (f.exists()) {
f.delete();
}
try {
FileOutputStream out = new FileOutputStream(f);
bm.compress(Bitmap.CompressFormat.PNG, 90, out);
out.flush();
out.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

//获取视频缩略图
public static Bitmap getVideoThumbnail(String filePath) {
Bitmap bitmap = null;
MediaMetadataRetriever retriever = new MediaMetadataRetriever();
try {
retriever.setDataSource(filePath);
bitmap = retriever.getFrameAtTime();
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (RuntimeException e) {
e.printStackTrace();
} finally {
try {
retriever.release();
} catch (RuntimeException e) {
e.printStackTrace();
}
}
return bitmap;
}
/**
* 毛化玻璃效果
*
* @param context
* @param radius     毛化程度（取值0-24）
* @param sentBitmap 原图片
*/
public static Bitmap blur(Context context, float radius, Bitmap sentBitmap) {
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);
script.setInput(input);
script.forEach(output);
output.copyTo(bitmap);
return bitmap;
}