Passing bitmap to Tesseract in Android

Question

I am trying to pass a bitmap to tesseract to get the read characters. I have written the code in this way:

TessBaseAPI baseApi = new TessBaseAPI();
baseApi.setImage(ReadFile.readBitmap(charscropped));
String capturedChars = baseApi.getUTF8Text(); // app crashes in this line

What is missing here?

Logcat output:

11-03 15:00:54.473: E/AndroidRuntime(5674): FATAL EXCEPTION: main
11-03 15:00:54.473: E/AndroidRuntime(5674): java.lang.NullPointerException
11-03 15:00:54.473: E/AndroidRuntime(5674):     at com.googlecode.tesseract.android.TessBaseAPI.getUTF8Text(TessBaseAPI.java:409)
11-03 15:00:54.473: E/AndroidRuntime(5674):     at com.elottery.ocr.Test$4.onClick(Test.java:110)
11-03 15:00:54.473: E/AndroidRuntime(5674):     at android.view.View.performClick(View.java:3567)
11-03 15:00:54.473: E/AndroidRuntime(5674):     at android.view.View$PerformClick.run(View.java:14224)
11-03 15:00:54.473: E/AndroidRuntime(5674):     at android.os.Handler.handleCallback(Handler.java:605)
11-03 15:00:54.473: E/AndroidRuntime(5674):     at android.os.Handler.dispatchMessage(Handler.java:92)
11-03 15:00:54.473: E/AndroidRuntime(5674):     at android.os.Looper.loop(Looper.java:137)
11-03 15:00:54.473: E/AndroidRuntime(5674):     at android.app.ActivityThread.main(ActivityThread.java:4517)
11-03 15:00:54.473: E/AndroidRuntime(5674):     at java.lang.reflect.Method.invokeNative(Native Method)
11-03 15:00:54.473: E/AndroidRuntime(5674):     at java.lang.reflect.Method.invoke(Method.java:511)
11-03 15:00:54.473: E/AndroidRuntime(5674):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:993)
11-03 15:00:54.473: E/AndroidRuntime(5674):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:760)
11-03 15:00:54.473: E/AndroidRuntime(5674):     at dalvik.system.NativeStart.main(Native Method)

Answer 1

I got this working after referring to Gautam Gupta's blog: http://gaut.am/making-an-ocr-android-app-using-tesseract/

The problem was that language files were missing and I manually placed them in phone sdcard. Following are the lines of code:

TessBaseAPI baseApi = new TessBaseAPI();
baseApi.init("/mnt/sdcard/tesseract", "eng"); 
baseApi.setImage(ReadFile.readBitmap(charscropped));
String capturedChars = baseApi.getUTF8Text();

Answer 2

The error is not in that line it is in above line. Pass the Bitmap's object directly to baseApi.setImage();

Like Eg:-

Bitmap bmp;
and then store the image in bmp
baseApi.setImage(bmp);

It worked for me.