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ZXing convert Bitmap to BinaryBitmap

Tags:

android

zxing

I am using OpenCV and Zxing, and I'd like to add 2d code scanning. I have a few types of images that I could send. Probably the best is Bitmat (the other option is OpenCV Mat).

It looks like you used to be able to convert like this:

Bitmap frame = //this is the frame coming in

LuminanceSource source = new RGBLuminanceSource(frame);
BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));

//then I can use reader.decode(bitmap) to decode the BinaryBitmap

However, RGBLuminaceSource looks like it no longer takes a bitmap as an input. So how else can I convert an input image to BinaryBitmap???

Edit:

Ok so I believe I've made some progress, but I'm still having an issue. I think I have the code that converts the Bitmap into the correct format, however I am now getting an arrayIndexOutOfBounds

public void zxing(){
    Bitmap bMap = Bitmap.createBitmap(frame.width(), frame.height(), Bitmap.Config.ARGB_8888);
    Utils.matToBitmap(frame, bMap);
    byte[] array = BitmapToArray(bMap);
    LuminanceSource source = new PlanarYUVLuminanceSource(array, bMap.getWidth(), bMap.getHeight(), 0, 0, bMap.getWidth(), bMap.getHeight(), false);
        
    BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
    Reader reader = new DataMatrixReader();
    String sResult = "";
    try {
        Result result = reader.decode(bitmap);
        sResult = result.getText();
        Log.i("Result", sResult);
        }
    catch (NotFoundException e) {
            Log.d(TAG, "Code Not Found");
            e.printStackTrace();
    }
}

public byte[] BitmapToArray(Bitmap bmp){
    ByteArrayOutputStream stream = new ByteArrayOutputStream();
    bmp.compress(Bitmap.CompressFormat.JPEG, 50, stream);
    byte[] byteArray = stream.toByteArray();
    return byteArray;
}

I get the error

02-14 10:19:27.469: E/AndroidRuntime(29736): java.lang.ArrayIndexOutOfBoundsException: length=33341; index=34560 02-14 10:19:27.469: E/AndroidRuntime(29736):   at 
com.google.zxing.common.HybridBinarizer.calculateBlackPoints(HybridBinarizer.java:199)

I have logged the size of the byte[], and it is the length shown above. I cant figure out why zxing is expecting it to be bigger

like image 386
Jameo Avatar asked Feb 13 '13 19:02

Jameo


1 Answers

Ok I got it. As Sean Owen said, PlanarYUVLuminaceSource would only be for the default android camera format, which I guess OpenCV does not use. So in short, here is how you would do it:

//(note, mTwod is the CV Mat that contains my datamatrix code)

Bitmap bMap = Bitmap.createBitmap(mTwod.width(), mTwod.height(), Bitmap.Config.ARGB_8888);
Utils.matToBitmap(mTwod, bMap);
int[] intArray = new int[bMap.getWidth()*bMap.getHeight()];  
//copy pixel data from the Bitmap into the 'intArray' array  
bMap.getPixels(intArray, 0, bMap.getWidth(), 0, 0, bMap.getWidth(), bMap.getHeight());  

LuminanceSource source = new RGBLuminanceSource(bMap.getWidth(), bMap.getHeight(),intArray);

BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
Reader reader = new DataMatrixReader();     
//....doing the actually reading
Result result = reader.decode(bitmap);

So thats it, not hard at all. Just had to convert the Android Bitmap to an integer array, and its a piece of cake.

like image 125
Jameo Avatar answered Jan 01 '23 09:01

Jameo