频繁setImageBitmap引起oom问题解决方法
Glide.with(gsewmimg).load(getCodeBitmap(response.data.skip, R.mipmap.zhifuicon)).into(gsewmimg);
压缩前后。图片大小 2.22MB——>200KB
1、图片压缩方法：
Bitmap bitmap;
byte[] buff;
buff = Bitmap2Bytes(bitmap);
BitmapFactory.Options ontain = new BitmapFactory.Options();
ontain.inSampleSize = 7;//值1为原图。值越大，压缩图片越小1-20
bitmap = BitmapFactory.decodeByteArray(buff, 0, buff.length, ontain);
压缩方法2：
int height = (int) ( mybitmap.getHeight() * (512.0 / mybitmap.getWidth()) );
mybitmap = Bitmap.createScaledBitmap(mybitmap, 512, height, true);
2、bitmap转byte
private byte[] Bitmap2Bytes(Bitmap bm) {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
bm.compress(Bitmap.CompressFormat.PNG, 100, baos);
return baos.toByteArray();
}
3、byte转bitmap
private Bitmap Bytes2Bimap(byte[] b) {
if (b.length != 0) {
return BitmapFactory.decodeByteArray(b, 0, b.length);
} else {
return null;
}
}
方法二，bitmap 转byte
Bitmap frame = mCamera != null ? mCamera.Snapshot(mSelectedChannel) : null;frame = rotate(frame, 90);byte[] snapshot = getByteArrayFromBitmap(frame);if (snapshot!=null){String imageString = new String(Base64.encode(snapshot,Base64.DEFAULT));
// LgqLogPlus.e("获取到imgstring保存了===== "+imageString);SharedPreUtil.putString(mDevUID,imageString);}
public static byte[] getByteArrayFromBitmap(Bitmap bitmap) {if (bitmap != null && !bitmap.isRecycled()) {ByteArrayOutputStream bos = new ByteArrayOutputStream();bitmap.compress(Bitmap.CompressFormat.PNG, 0, bos);return bos.toByteArray();} else {return null;}
}
byte转bitmap
String imgstring = SharedPreUtil.getString(this,mDevUID);
// LgqLogPlus.e("获取到imgstring==== "+imgstring);if (imgstring!=null){byte[] bytsSnapshot = Base64.decode(imgstring.getBytes(), Base64.DEFAULT);Bitmap snapshot = (bytsSnapshot != null && bytsSnapshot.length > 0) ? getBitmapFromByteArray(bytsSnapshot) : null;bgimg.setImageBitmap(snapshot);}
public static Bitmap getBitmapFromByteArray(byte[] byts) {InputStream is = new ByteArrayInputStream(byts);return BitmapFactory.decodeStream(is, null, getBitmapOptions(2));
}public static BitmapFactory.Options getBitmapOptions(int scale) {BitmapFactory.Options options = new BitmapFactory.Options();options.inPurgeable = true;options.inInputShareable = true;options.inSampleSize = scale;try {BitmapFactory.Options.class.getField("inNativeAlloc").setBoolean(options, true);} catch (IllegalArgumentException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (SecurityException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (NoSuchFieldException e) {// TODO Auto-generated catch blocke.printStackTrace();}return options;
}
旋转方法：
//Rotate Bitmap
public final static Bitmap rotate(Bitmap b, float degrees) {if (degrees != 0 && b != null) {Matrix m = new Matrix();m.setRotate(degrees, (float) b.getWidth() / 2,(float) b.getHeight() / 2);Bitmap b2 = Bitmap.createBitmap(b, 0, 0, b.getWidth(),b.getHeight(), m, true);if (b != b2) {b.recycle();b = b2;}}return b;
}调用
bitmap = rotate(bitmap,90);效果
选图
Android报错：Throwing OutOfMemoryError failed to allocate a 42793710 byte allocation with 52488 free by
在<application>里加上android:hardwareAccelerated="false" 和 android:largeHeap="true"成功解决
Bitmap与String互转
Bitmap frame = BitmapFactory.decodeResource(getResources(),R.mipmap.iv_charge2 );byte[] snapshot = getByteArrayFromBitmap(frame);if (snapshot!=null){String imageString = new String(Base64.encode(snapshot,Base64.DEFAULT));if (imageString!=null){byte[] bytsSnapshot = Base64.decode(imageString.getBytes(), Base64.DEFAULT);Bitmap snapshot2 = (bytsSnapshot != null && bytsSnapshot.length > 0) ? getBitmapFromByteArray(bytsSnapshot) : null;imageView.setImageBitmap(snapshot2);}
}
工具：
public static byte[] getByteArrayFromBitmap(Bitmap bitmap) {if (bitmap != null && !bitmap.isRecycled()) {ByteArrayOutputStream bos = new ByteArrayOutputStream();bitmap.compress(Bitmap.CompressFormat.PNG, 0, bos);return bos.toByteArray();} else {return null;}
}public static Bitmap getBitmapFromByteArray(byte[] byts) {InputStream is = new ByteArrayInputStream(byts);return BitmapFactory.decodeStream(is, null, getBitmapOptions(2));
}public static BitmapFactory.Options getBitmapOptions(int scale) {BitmapFactory.Options options = new BitmapFactory.Options();options.inPurgeable = true;options.inInputShareable = true;options.inSampleSize = scale;try {BitmapFactory.Options.class.getField("inNativeAlloc").setBoolean(options, true);} catch (IllegalArgumentException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (SecurityException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (NoSuchFieldException e) {// TODO Auto-generated catch blocke.printStackTrace();}return options;
}
private static void readBitmapScale(Context context, Uri uri, BitmapFactory.Options options) {if (uri == null) {return;}String scheme = uri.getScheme();if (ContentResolver.SCHEME_CONTENT.equals(scheme) ||ContentResolver.SCHEME_FILE.equals(scheme)) {InputStream stream = null;try {stream = context.getContentResolver().openInputStream(uri);BitmapFactory.decodeStream(stream, null, options);} catch (Exception e) {Log.w("readBitmapScale", "Unable to open content: " + uri, e);} finally {if (stream != null) {try {stream.close();} catch (IOException e) {Log.e("readBitmapScale", "Unable to close content: " + uri, e);}}}} else if (ContentResolver.SCHEME_ANDROID_RESOURCE.equals(scheme)) {Log.e("readBitmapScale", "Unable to close content: " + uri);} else {Log.e("readBitmapScale", "Unable to close content: " + uri);}
}private static Bitmap readBitmapData(Context context, Uri uri, BitmapFactory.Options options) {if (uri == null) {return null;}Bitmap bitmap = null;String scheme = uri.getScheme();if (ContentResolver.SCHEME_CONTENT.equals(scheme) ||ContentResolver.SCHEME_FILE.equals(scheme)) {InputStream stream = null;try {stream = context.getContentResolver().openInputStream(uri);bitmap = BitmapFactory.decodeStream(stream, null, options);} catch (Exception e) {Log.e("readBitmapData", "Unable to open content: " + uri, e);} finally {if (stream != null) {try {stream.close();} catch (IOException e) {Log.e("readBitmapData", "Unable to close content: " + uri, e);}}}} else if (ContentResolver.SCHEME_ANDROID_RESOURCE.equals(scheme)) {Log.e("readBitmapData", "Unable to close content: " + uri);} else {Log.e("readBitmapData", "Unable to close content: " + uri);}return bitmap;
}
