ZXing convert Bitmap to BinaryBitmap

问题:

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

回答1:

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.

回答2:

public static String readQRImage(Bitmap bMap) {     String contents = null;      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 MultiFormatReader();// use this otherwise ChecksumException     try {         Result result = reader.decode(bitmap);         contents = result.getText();          //byte[] rawBytes = result.getRawBytes();          //BarcodeFormat format = result.getBarcodeFormat();          //ResultPoint[] points = result.getResultPoints();     } catch (NotFoundException e) { e.printStackTrace(); }      catch (ChecksumException e) { e.printStackTrace(); }     catch (FormatException e) { e.printStackTrace(); }      return contents; } 

回答3:

Bitmap is an Android class. Android's default image format from the camera is a planar YUV format. That is why only PlanarYUVLuminanceSource is needed and exists for Android. RGBLuminanceSource would have to be ported.

You are putting completely the wrong kind of data into the class. It is expecting pixels in YUV planar format. You are passing compressed bytes of a JPEG file.

文章来源: ZXing convert Bitmap to BinaryBitmap