Android Question OCR offline - fixed area


Licensed User
Longtime User
I have seen that there is more than one OCR library for B4A.

Before I start trying them all, I'd like to know if anyone has been able to get the features listed below and then recommend the library to use.

1 - it works offline
2 - the recognition is carried out only in a small rectangle. The ideal would be that only in that rectangle you see what the lens frames, but a rectangle drawn over the full-screen shot would also be fine.

Thank you.


Licensed User
I use MobileVisionBitmap which seems to work fine. It OCRs a whole bitmap but in theory, you could crop that bitmap before the OCR. Haven't tried it though.
I once tried playing with params TargetWidth & TargetHeight, trying to limit the area read but it didn't seem to work as expected so I don't touch those now.

Sub Globals
    Private mstrOcrWords As String
End Sub

Sub OcrPic(bmp as BitMap, Left as Int, Top As Int, Width As Int, Height as Int))
    Dim mvbm As MobileVisionBitmap
    mvbm.TargetWidth = bmp.Width
    mvbm.TargetHeight = bmp.Height
    mstrOcrWords = ""
    Dim bmp1 As Bitmap = bmp.Crop(Left, Top, Width, Height)
    mvbm.decodeBitmap(bmp1)                'triggers mvbm_blocks_result() & mvbm_words_result()
End Sub           

Sub mvbm_words_result(words As String)
    ' Words are comma delimited
    mstrOcrWords = words
End Sub
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