public class BitmapUtils {
/**
* 获取网络图片资源
* @param url
* @return
*/
public static Bitmap getHttpBitmap(String url){
URL myFileURL;
Bitmap bitmap=null;
try{
myFileURL = new URL(url);
//获得连接
HttpURLConnection conn=(HttpURLConnection)myFileURL.openConnection();
//设置超时时间为6000毫秒，conn.setConnectionTiem(0);表示没有时间限制
conn.setConnectTimeout(6000);
//连接设置获得数据流
conn.setDoInput(true);
//不使用缓存
conn.setUseCaches(false);
//这句可有可无，没有影响
//conn.connect();
//得到数据流
InputStream is = conn.getInputStream();
//解析得到图片
bitmap = BitmapFactory.decodeStream(is);
//关闭数据流
is.close();
}catch(Exception e){
e.printstacktrace();
}
return bitmap;
}
/**
* 以最省内存的方式读取本地资源的<a href="https://www.jb51.cc/tag/tupian/" target="_blank" class="keywords">图片</a>
* @p<a href="https://www.jb51.cc/tag/ara/" target="_blank" class="keywords">ara</a>m context
* @p<a href="https://www.jb51.cc/tag/ara/" target="_blank" class="keywords">ara</a>m resId
* @return
*/
public static Bitmap readBitMap(Context context,int resId){
BitmapFactory.Options opt = new BitmapFactory.Options();
opt.inPreferredCon<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a> = Bitmap.Con<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a>.RGB_565;
opt.inPurgeable = true;
opt.inInputShareable = true;
//<a href="https://www.jb51.cc/tag/huoqu/" target="_blank" class="keywords">获取</a>资源<a href="https://www.jb51.cc/tag/tupian/" target="_blank" class="keywords">图片</a>
InputStream is = context.getResources().openRawResource(resId);
return BitmapFactory.decodeStream(is,null,opt);
}
/**
* 通过传入Path和ImageView加载相应的<a href="https://www.jb51.cc/tag/tupian/" target="_blank" class="keywords">图片</a>
* 对<a href="https://www.jb51.cc/tag/tupian/" target="_blank" class="keywords">图片</a>加载的优化
* @p<a href="https://www.jb51.cc/tag/ara/" target="_blank" class="keywords">ara</a>m imageView
*/
public static void loadPicture(ImageView imageView,String Path){
int reqWidth = imageView.getWidth();
int reqHeight = imageView.getHeight();
Bitmap bitmap = decodeSampledBitmapFromFile(Path,reqWidth,reqHeight);
if (bitmap != null){
imageView.se<a href="https://www.jb51.cc/tag/timage/" target="_blank" class="keywords">timage</a>Bitmap(bitmap);
}
}
public static Bitmap decodeSampledBitmapFromFile(String strPath,int reqWidth,int reqHeight) {
// 第一次解析将inJustDecodeBounds设置为true，来<a href="https://www.jb51.cc/tag/huoqu/" target="_blank" class="keywords">获取</a><a href="https://www.jb51.cc/tag/tupian/" target="_blank" class="keywords">图片</a>大小
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(strPath,options);
// <a href="https://www.jb51.cc/tag/diaoyong/" target="_blank" class="keywords">调用</a>上面定义的<a href="https://www.jb51.cc/tag/fangfa/" target="_blank" class="keywords">方法</a>计算inSampleSize值
options.inSampleSize = cal<a href="https://www.jb51.cc/tag/cula/" target="_blank" class="keywords">cula</a>teInSampleSize(options,reqHeight);
// 使用<a href="https://www.jb51.cc/tag/huoqu/" target="_blank" class="keywords">获取</a>到的inSampleSize值再次解析<a href="https://www.jb51.cc/tag/tupian/" target="_blank" class="keywords">图片</a>
options.inJustDecodeBounds = false;
return BitmapFactory.decodeFile(strPath,options);
}
public static int cal<a href="https://www.jb51.cc/tag/cula/" target="_blank" class="keywords">cula</a>teInSampleSize(BitmapFactory.Options options,int reqHeight) {
// 源<a href="https://www.jb51.cc/tag/tupian/" target="_blank" class="keywords">图片</a>的高度和宽度
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
// 计算出实际宽高和目标宽高的比率
final int heightRatio = Math.round((float) height / (float) reqHeight);
final int widthRatio = Math.round((float) width / (float) reqWidth);
// 选择宽和高中最小的比率作为inSampleSize的值，这样可以保证最终<a href="https://www.jb51.cc/tag/tupian/" target="_blank" class="keywords">图片</a>的宽和高
// 一定都会大于等于目标的宽和高。
inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
}
return inSampleSize;
}
/**
*保存图片到文件
*/
public static File saveBitmapToFile(Bitmap bitmap) {
//如果相等的话表示当前的sdcard挂载在手机上并且是可用的
if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
String storePath = Environment.getExternalStorageDirectory().toString() + "/yingzhidao/"+"header.jpg";
File file = new File(storePath);
if (!file.exists()){
file.mkdir();
}
try {
BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(file));
bitmap.compress(Bitmap.CompressFormat.PNG,100,bos);
bos.flush();
bos.close();
} catch (IOException e) {
e.printStackTrace();
}
return file;
}
return null;
}
/**
* 压缩图片到制定大小
* @param bitmap
* @param size
* @return
*/
public static Bitmap imageZoom(Bitmap bitmap,double size) {
Bitmap targetBitmap = null;
targetBitmap = bitmap;
//图片允许最大空间 单位：KB
double maxSize =size;
//将bitmap放至数组中，意在bitmap的大小（与实际读取的原文件要大）
ByteArrayOutputStream baos = new ByteArrayOutputStream();
targetBitmap.compress(Bitmap.CompressFormat.JPEG,baos);
byte[] b = baos.toByteArray();
//将字节换成KB
double mid = b.length/1024;
//判断bitmap占用空间是否大于允许最大空间 如果大于则压缩 小于则不压缩
if (mid > maxSize) {
//<a href="https://www.jb51.cc/tag/huoqu/" target="_blank" class="keywords">获取</a>bitmap大小 是允许最大大小的多少倍
double i = mid / maxSize;
//开始压缩 此处用到平方根 将宽带和高度压缩掉对应的平方根倍 （1.保持刻度和高度和原bitmap比率一致，压缩后也达到了最大大小占用空<a href="https://www.jb51.cc/tag/jiande/" target="_blank" class="keywords">间的</a>大小）
targetBitmap = zoomImage(targetBitmap,targetBitmap.getWidth() / Math.sqrt(i),targetBitmap.getHeight() / Math.sqrt(i));
}
return targetBitmap;
}
public static Bitmap zoomImage(Bitmap bgimage,double newWidth,double newHeight) {
// <a href="https://www.jb51.cc/tag/huoqu/" target="_blank" class="keywords">获取</a>这个<a href="https://www.jb51.cc/tag/tupian/" target="_blank" class="keywords">图片</a>的宽和高
float width = bgimage.getWidth();
float height = bgimage.getHeight();
// 创建操作<a href="https://www.jb51.cc/tag/tupian/" target="_blank" class="keywords">图片</a>用的matrix对象
Matrix matrix = new Matrix();
// 计算宽高缩放率
float scaleWidth = ((float) newWidth) / width;
float scaleHeight = ((float) newHeight) / height;
// 缩放<a href="https://www.jb51.cc/tag/tupian/" target="_blank" class="keywords">图片</a>动作
matrix.postScale(scaleWidth,scaleHeight);
Bitmap bitmap = Bitmap.createBitmap(bgimage,(int) width,(int) height,matrix,true);
return bitmap;
}
/**
*为<a href="https://www.jb51.cc/tag/tupian/" target="_blank" class="keywords">图片</a><a href="https://www.jb51.cc/tag/tianjia/" target="_blank" class="keywords">添加</a>水印
*/
public static Bitmap drawTextToBitmap(Context gContext,int gResId,String text) {
Resources resources = gContext.getResources();
// float scale = resources.get<a href="https://www.jb51.cc/tag/dis/" target="_blank" class="keywords">dis</a>playMetrics().density;
Bitmap bitmap =
BitmapFactory.decodeResource(resources,gResId);
android.graphics.Bitmap.Con<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a> bitmapCon<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a> =
bitmap.getCon<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a>();
// set default bitmap con<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a> if none
if(bitmapCon<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a> == null) {
bitmapCon<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a> = android.graphics.Bitmap.Con<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a>.ARGB_8888;
}
// resource bitmaps are imutable,// so we need to convert it to mutable one
bitmap = bitmap.<a href="https://www.jb51.cc/tag/cop/" target="_blank" class="keywords">cop</a>y(bitmapCon<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a>,true);
int height = bitmap.getHeight();
int width = bitmap.getWidth();
// new antialised Paint
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
// text color - #3D3D3D
paint.setColor(Color.rgb(255,255,255));
// text size in pixels
paint.setTextSize(32);
// text shadow
// paint.setShadowLayer(1f,0f,1f,Color.WHITE);
// draw text to the Canvas center
Rect bounds = new Rect();
paint.getTextBounds(text,text.length(),bounds);
Log.i("NEC","text width:"+bounds.width());
Log.i("NEC","text high:" + bounds.height());
int targetWidth = bounds.width()+40;
Matrix matrix = new Matrix();
float scaleWidth = ((float) targetWidth) / width;
float scaleHeight = ((float) height) / height;
matrix.postScale(scaleWidth,scaleHeight);
Bitmap scaleBitmap = Bitmap.createBitmap(bitmap,width,height,true);
int x = (scaleBitmap.getWidth() - bounds.width())/2;
int y = (scaleBitmap.getHeight() + bounds.height())/2-8;
Canvas canvas = new Canvas(scaleBitmap);
canvas.drawText(text,x,y,paint);
if(!bitmap.isRecycled())
{
bitmap.recycle();
bitmap = null;
}
return scaleBitmap;
}
}
/**
- 传入Bitmap和图片的Url名字，判断系统是否旋转过图片，如果旋转过则纠正
- @param Bitmap
- @param String
- @return Bitmap
*/
public static Bitmap changeRotation(Bitmap bmp,String path){
CompareActivity.IS_ROTATION = false;
int degree = 0;
ExifInterface exifInterface;
try {
exifInterface = new ExifInterface(path);
int tag = exifInterface.getAttributeInt(ExifInterface.TAG_ORIENTATION,-1);
switch (tag) {
case ExifInterface.ORIENTATION_ROTATE_90:
degree = 90;
CompareActivity.IS_ROTATION = true;
break;
case ExifInterface.ORIENTATION_ROTATE_180:
degree = 180;
CompareActivity.IS_ROTATION = true;
break;
case ExifInterface.ORIENTATION_ROTATE_270:
degree = 270;
CompareActivity.IS_ROTATION = true;
break;
default:
break;
}
Matrix matrix = new Matrix();
matrix.postRotate(degree);
if (bmp != null){
bmp = Bitmap.createBitmap(bmp,bmp.getWidth(),bmp.getHeight(),true);
}
} catch (IOException e) {
e.printstacktrace();
}
return bmp;
}
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