Develop Reference

(Unity) How to read old game data on Android?

I created and published a game for android with AndEngine three years ago. Now I am preparing the game again with unity. When I send an update, all of the old data is deleted. Because Unity using 'PlayerPrefs' and Android using 'SharedPreferences'.
So, How do I read old data with Unity?
Here is my old code setup:
private SharedPreferences data;
private SharedPreferences.Editor editor;
// ======================================================================
public void setup(Activity activity) {
data = activity.getSharedPreferences("kayit", 0);
editor = data.edit();
}

I don't think its going to be easy accessing persistent data saved with a different engine - but a solution I can see is release an update with the old engine that will upload the data to a remote server, and then download it using Unity, but since you already released the unity version that might not work for you

PlayerPrefs and SharedPreferences are different things.
But there is a solution.
Unity allows to add native android Java or C++ code to your Unity project and use interfaces to access that code.
So you can write some code using Android SDK/NDK methods to access your SharedPreferences and add it as JAR or AAR to your Unity project.
Read about it in the official documentation https://docs.unity3d.com/Manual/PluginsForAndroid.html

private void ReadAndroidSharedPreferences(string packageName, string xmlDataName)
{
string path = "/data/data/" + packageName + "/shared_prefs/" + xmlDataName + ".xml";
FileStream levelFile = File.Open(path, FileMode.Open);
XmlDocument xmlDoc = new XmlDocument();
string xmlText = "";
using (StreamReader sr = new StreamReader(levelFile))
{
string line = null;
do
{
line = sr.ReadLine();
xmlText = xmlText + line + "\n";
} while (line != null);
sr.Close();
levelFile.Close();
}
xmlDoc.LoadXml(xmlText);
var baseNode = xmlDoc.DocumentElement;
foreach (XmlNode node in baseNode.ChildNodes)
{
Debug.Log("Type: " + node.Name);
if (node.Attributes["name"] != null)
Debug.Log("name: " + node.Attributes["name"].Value);
else
Debug.Log("Empty");
if (node.Attributes["value"] != null)
Debug.Log("Value: " + node.Attributes["value"].Value);
else
Debug.Log("Empty");
}
}
Usage:
packageName = "com.yourcompany.yourgame"
xmlDataName = getSharedPreferences file name (in my question, it's "kayit")
You can see all 'int' and 'bool' data on Android Device Monitor.

Rendering jp2(jpeg2000) to Imageview in android.

I am getting jp2 in base64 format from server end. I am able to convert jpg to jp2 form ImageMagick library and send to server. They are able to convert it to jpg using Buffered Image and ImageIo .
But I am not getting any idea to convert jp2 to jpg and render in Imageview.
Hoping for any help. Thanks in advance.

You probably solved it somehow already, but in case you're still looking for a solution, you can try the JP2 for Android library. (Disclaimer: I wrote the library.) It's based on OpenJPEG, like the DimaArts' response, but it has a bit nicer Java interface.
Add the following dependency to your build.gradle file:
implementation 'com.gemalto.jp2:jp2-android:1.0'
and use the following code to decode the JP2:
byte[] jp2Data = ...; //get the JP2 data from somewhere
Bitmap bmp = new JP2Decoder(jp2Data).decode();
imgView.setImageBitmap(bmp);

You can use OpenJpeg library for decode Jpeg2000. You can use compiled library https://github.com/DimaArts/OpenJpegAndroid. It contains an example of encode jpeg2000. Library supports PNG input and output formats for decoder and encoder.
Try this:
OpenJPEGJavaDecoder decoder = new OpenJPEGJavaDecoder();
String[] params2 = new String[4];
params2[0] = "-i";
params2[1] = mInputPath; // path to jp2
params2[2] = "-o";
params2[3] = mOutputPath // path to png
decoder.decodeJ2KtoImage(params2);
if you are using JNI:
public int decodeJ2KtoImage(String[] parameters) {
return internalDecodeJ2KtoImage(parameters);
}

Try this code from https://stackoverflow.com/a/39103107/2760681
private static void convertImage(int randNum) throws IOException {
try {
File foundFile = new File("c:\\images\\" + randNum + ".jp2");
BufferedImage background = ImageIO.read(foundFile);
ImageIO.write(background, "jpg", new File("c:\\images\\" + randNum + ".jpg"));
System.out.println("jpg file is generated");
} catch (Exception e) {
// TODO: handle exception
System.out.println("No file " + randNum +".jp2 found");
}
}

Could not initialize Tesseract API with language=eng

I am working on an Android app that requires OCR. I have decided to use Tesseract as API but I keep on getting this error:
E/Tesseract(native): Could not initialize Tesseract API with language=eng!
I have already copied file "eng.traineddata" to the location.
I am using Android Studio 2.1.2 (SDK 23)
Testing on device with API 22 Android Lollipop 5.1.1 (Read about Permission issue on Marshmallow)
Here is the code I am using:
public void reads(View view) {
TextView textView = (TextView) findViewById(R.id.textView);
int rotation = 0;
try {
ExifInterface exifInterface = new ExifInterface(mCurrentPhotoPath);
int orientation = exifInterface.getAttributeInt(ExifInterface.TAG_ORIENTATION,ExifInterface.ORIENTATION_NORMAL);
switch (orientation){
case ExifInterface.ORIENTATION_ROTATE_90: rotation = 90; break;
case ExifInterface.ORIENTATION_ROTATE_180: rotation = 180; break;
case ExifInterface.ORIENTATION_ROTATE_270: rotation = 270; break;
}
} catch(Exception e) {
}
int w = imageBitmap.getWidth();
int h = imageBitmap.getHeight();
if (rotation != 0) {
Matrix matrix = new Matrix();
matrix.preRotate(rotation);
imageBitmap = Bitmap.createBitmap(imageBitmap,0,0,w,h,matrix,false);
} else {
imageBitmap = Bitmap.createBitmap(imageBitmap,0,0,w,h);
}
imageBitmap = imageBitmap.copy(Bitmap.Config.ARGB_8888,true);
TessBaseAPI ReadIt = new TessBaseAPI();
ReadIt.init("/storage/emulated/0/","eng");
ReadIt.setImage(imageBitmap);
String Text = ReadIt.getUTF8Text();
if (Text!=null) textView.setText(Text);
}
I have used this line in my build.gradle dependency:
compile 'com.rmtheis:tess-two:6.0.2'
also, I have copied the"eng.traineddata in the folder named tessdata directly by downloading in the particular stated directory.

Tesseract-two isn't using the newest version of the OCR engine, it uses 3.05, so we are forced to use data from here. It seems the new data uses a different model, neural networks. The previous models before 4.0 worked differently.
I have tried using the data from here
and here. These data sets are only compatible with the newest version of tesseract, 4.0 (source), so it won't work if you are using an older version of tesseract.

Are you using tess-two?. In your code:
TessBaseAPI ReadIt = new TessBaseAPI();
ReadIt.init("/storage/emulated/0/","eng");
"/storage/emulated/0/" path should be pointing to your data files. You must have a subdirectory
named "tessdata". See
https://github.com/rmtheis/tess-two/blob/d7a45fd2e08b7ec315cd1e29d1a7e0c72fb24a66/tess-two/src/com/googlecode/tesseract/android/TessBaseAPI.java#L176
Read more at:
Could not initialize Tesseract API with language=eng!

Release permissions of manifest in Activity:
In manifest:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
In onCreate:
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.WRITE_EXTERNAL_STORAGE)
!= PackageManager.PERMISSION_GRANTED) {
// Should we show an explanation?
if (ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
} else {
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
1);
}
}

If you dont use Marshmallow and still have problem try clean and rebuild project.

I had this same issue and the problem was that Marshmallow specifically requires a new way for your app to get read/write permission to storage. This blog post solved my problem.
In my Main Activity I have the following:
#Override
protected void onCreate(Bundle savedInstanceState) {
...
...
getStorageAccessPermissions(); // Request storage read/write permissions from the user
}
#TargetApi(23)
private void getStorageAccessPermissions() {
int hasWriteStoragePermission = checkSelfPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE);
if (hasWriteStoragePermission != PackageManager.PERMISSION_GRANTED) {
requestPermissions(new String[] {Manifest.permission.WRITE_EXTERNAL_STORAGE}, REQUEST_CODE_WRITE_EXTERNAL_PERMISSIONS);
}
}
Where REQUEST_CODE_WRITE_EXTERNAL_PERMISSIONS is an integer constant declared globally.
In a class that I have extending TessBaseAPI I added the following just for logging purposes to make sure that I actually can access the storage.
/* Checks if external storage is available to at least write to and returns the path name */
private static String isExternalStorageWritable() {
String state = Environment.getExternalStorageState();
String retval = "External storage is not writable";
if (Environment.MEDIA_MOUNTED.equals(state)) {
retval = Environment.getExternalStorageDirectory().toString();
}
return retval;
}
/* Checks if external storage is available to at least read from and returns the path name */
private static String isExternalStorageReadable() {
String state = Environment.getExternalStorageState();
String retval = "External storage is not readable";
if (Environment.MEDIA_MOUNTED.equals(state) ||
Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) {
retval = Environment.getExternalStorageDirectory().toString();
}
return retval;
}

use absolute path to tessdata directory from external storage (not assets)
for example if your models are in
/storage/emulated/0/Android/data/com.xxx.yyy/files/tessmodels/tessdata/
use this path
/storage/emulated/0/Android/data/com.xxx.yyy/files/tessmodels/
make sure you have write/read external storage permissions
use this model, tested with tess-two:9.0.0. I got it from tess-two sample app

Newer versions of tess-two check to make sure that the training data files can be found on the device. If those training data files are not found, a more informative message than the error message you're seeing will be shown.
So when you see this error message on newer versions of tess-two, it means that the training data files were found in the expected location, but they are the wrong version or are otherwise unreadable. Check to make sure you're using the right version of the training data files.

Using Google Cloud Storage JSON api in android

I want to upload image on Google Cloud Storage from my android app. For that I searched and found that GCS JSON Api provides this feature. I did a lot of research for Android sample which demonstrates its use. On the developer site they have provided code example that only support java. I don't know how to use that API in Android. I referred this and this links but couldn't get much idea. Please guide me on how i can use this api with android app.

Ok guys so I solved it and got my images being uploaded in Cloud Storage all good.
This is how:
Note: I used the XML API it is pretty much the same.
First, you will need to download a lot of libraries.
The easiest way to do this is create a maven project and let it download all the dependencies required. From this sample project :
Sample Project
The libraries should be:
Second, you must be familiar with Cloud Storage using the api console
You must create a project, create a bucket, give the bucket permissions, etc.
You can find more details about that here
Third, once you have all those things ready it is time to start coding.
Lets say we want to upload an image:
Cloud storage works with OAuth, that means you must be an authenticated user to use the API. For that the best way is to authorize using Service Accounts. Dont worry about it, the only thing you need to do is in the API console get a service account like this:
We will use this service account on our code.
Fourth, lets write some code, lets say upload an image to cloud storage.
For this code to work you must put your key generated in step 3 in assets folder, i named it "key.p12".
I don't recommend you to do this on your production version, since you will be giving out your key.
try{
httpTransport= new com.google.api.client.http.javanet.NetHttpTransport();
//agarro la key y la convierto en un file
AssetManager am = context.getAssets();
InputStream inputStream = am.open("key.p12"); //you should not put the key in assets in prod version.
//convert key into class File. from inputstream to file. in an aux class.
File file = UserProfileImageUploadHelper.createFileFromInputStream(inputStream,context);
//Google Credentianls
GoogleCredential credential = new GoogleCredential.Builder().setTransport(httpTransport)
.setJsonFactory(JSON_FACTORY)
.setServiceAccountId(SERVICE_ACCOUNT_EMAIL)
.setServiceAccountScopes(Collections.singleton(STORAGE_SCOPE))
.setServiceAccountPrivateKeyFromP12File(file)
.build();
String URI = "https://storage.googleapis.com/" + BUCKET_NAME+"/"+imagename+".jpg";
HttpRequestFactory requestFactory = httpTransport.createRequestFactory(credential);
GenericUrl url = new GenericUrl(URI);
//byte array holds the data, in this case the image i want to upload in bytes.
HttpContent contentsend = new ByteArrayContent("image/jpeg", byteArray );
HttpRequest putRequest = requestFactory.buildPutRequest(url, contentsend);
com.google.api.client.http.HttpResponse response = putRequest.execute();
String content = response.parseAsString();
Log.d("debug", "response is:"+response.getStatusCode());
Log.d("debug", "response content is:"+content);} catch (Exception e) Log.d("debug", "Error in user profile image uploading", e);}
This will upload the image to your cloud bucket.
For more info on the api check this link Cloud XML API

Firstly, You should get the below information by registering your application in the GCP console.
private final String pkcsFile = "xxx.json";//private key file
private final String bucketName = "your_gcp_bucket_name";
private final String projectId = "your_gcp_project_id";
Once you get the credentials, you should put the private key (.p12 or .json) in your assets folder. I'm using JSON format private key file. Also, you should update the image location to upload.
#RequiresApi(api = Build.VERSION_CODES.O)
public void uploadImageFile(String srcFileName, String newName) {
Storage storage = getStorage();
File file = new File(srcFileName);//Your image loaction
byte[] fileContent;
try {
fileContent = Files.readAllBytes(file.toPath());
} catch (IOException e) {
e.printStackTrace();
return;
}
if (fileContent == null || fileContent.length == 0)
return;
BlobInfo.Builder newBuilder = Blob.newBuilder(BucketInfo.of(bucketName), newName);
BlobInfo blobInfo = newBuilder.setContentType("image/png").build();
Blob blob = storage.create(blobInfo, fileContent);
String bucket = blob.getBucket();
String contentType = blob.getContentType();
Log.e("TAG", "Upload File: " + contentType);
Log.e("File ", srcFileName + " uploaded to bucket " + bucket + " as " + newName);
}
private Storage getStorage() {
InputStream credentialsStream;
Credentials credentials;
try {
credentialsStream = mContext.getAssets().open(pkcsFile);
credentials = GoogleCredentials.fromStream(credentialsStream);
} catch (IOException e) {
e.printStackTrace();
return null;
}
return StorageOptions.newBuilder()
.setProjectId(projectId).setCredentials(credentials)
.build().getService();
}

android ExifInterface platform 1.5, 1.6 [duplicate]

Is there any 3rd part api for android to read exif tags from image which support api level starting from 1.5.

The metadata extraction library by Drew Noakes works well for extracting EXIF tags on earlier Android platform versions, with a slight modification. I am using it on Android 1.6 to extract tags from JPEG images.
NOTE: Newer versions of metadata-extractor work directly on Android without modification.
You will need to download and build the source code yourself, and package it with your app. (I'm using release 2.3.1.) Make the following changes to com.drew.imaging.jpeg.JpegMetadataReader:
Remove the following import statement:
import com.sun.image.codec.jpeg.JPEGDecodeParam;
Delete the following method (which you won't need on Android):
public static Metadata readMetadata(JPEGDecodeParam decodeParam) { ... }
Remove the com.drew.metadata.SampleUsage class, which references the method deleted above. Also remove all of the test packages.
That's all there is to it. Here's an example of using the JpegMetadataReader to extract a date-time tag from a JPEG image stored on the SD card:
import com.drew.imaging.jpeg.JpegMetadataReader;
import com.drew.metadata.Directory;
import com.drew.metadata.Metadata;
import com.drew.metadata.exif.ExifDirectory;
// other imports and class definition removed for brevity
public static Date extractExifDateTime(String imagePath)
{
Log.d("exif", "Attempting to extract EXIF date/time from image at " + imagePath);
Date datetime = new Date(0); // or initialize to null, if you prefer
try
{
Metadata metadata = JpegMetadataReader.readMetadata(new File(imagePath));
Directory exifDirectory = metadata.getDirectory(ExifDirectory.class);
// these are listed in order of preference
int[] datetimeTags = new int[] { ExifDirectory.TAG_DATETIME_ORIGINAL,
ExifDirectory.TAG_DATETIME,
ExifDirectory.TAG_DATETIME_DIGITIZED };
int datetimeTag = -1;
for (int tag : datetimeTags)
{
if (exifDirectory.containsTag(tag))
{
datetimeTag = tag;
break;
}
}
if (datetimeTag != -1)
{
Log.d("exif", "Using tag " + exifDirectory.getTagName(datetimeTag) + " for timestamp");
SimpleDateFormat exifDatetimeFormat = new SimpleDateFormat("yyyy:MM:dd HH:mm:ss");
datetime = exifDatetimeFormat.parse(exifDirectory.getString(datetimeTag));
}
else
{
Log.d("exif", "No date/time tags were found");
}
}
catch (Exception e)
{
Log.w("exif", "Unable to extract EXIF metadata from image at " + imagePath, e);
}
return datetime;
}

For what it worth, did you try to use the native ExifInterface class ?
http://developer.android.com/reference/android/media/ExifInterface.html
Should be must faster than using a 3rd party library ;)