BarcodeDetector only detects in centre of the screen

[obsantos]

I'm using the BarcodeDetector from the Mobile Vision API on the Google Play Services (Version 10.2.0) for my app. I pretty much took the code from the sample app.

And the barcodes are only detected if they are in the middle/centre of the screen. Is there any way of increasing this to extend the whole screen/camera preview? Its a bit misleading for the user unless you add a rectangle in the centre leading them to place the barcode inside.

Even the sample app has this issue

Any help on how to accomplish this is welcome!

[pchx-zz]

What barcode format are you having trouble with?

Note that the DataMatrix detector only scans the center of the frame, but all other formats can be detected and read anywhere in the frame (though as a further caveat, 1D barcodes must be roughly horizontal/vertical).

[obsantos]

Its actually a DataMatrix.... Any reason or idea why it only scans the center of the frame? Is there any way of extending this to the whole frame?

Thanks for your response by the way!

[pchx-zz]

DataMatrix barcodes don't have markers that help distinguish them from the "background" or give detectors a rough idea of their size, unlike formats such as QR which have finder patterns. Without a finder pattern, reading a DataMatrix from an arbitrary location would be too slow to be usable.

[pulmuone]

my source..

hint...."(item as Barcode).BoundingBox.Intersect()"

//관심영역 지정
Rect rect = ((BarcodeScannerActivity)_activity).mPreview.mSurfaceView._clipBounds;
float left;
float right;
float top;
float bottom;

left = (rect.Left * (float)((BarcodeScannerActivity)_activity).mCameraSource.PreviewSize.Height) / (float)((BarcodeScannerActivity)_activity).mPreview.mSurfaceView.scaleNominatorX;
right = (rect.Right * (float)((BarcodeScannerActivity)_activity).mCameraSource.PreviewSize.Height) / (float)((BarcodeScannerActivity)_activity).mPreview.mSurfaceView.scaleNominatorX;

top = (rect.Top * (float)((BarcodeScannerActivity)_activity).mCameraSource.PreviewSize.Width) / (float)((BarcodeScannerActivity)_activity).mPreview.mSurfaceView.scaleNominatorY;
bottom = (rect.Bottom * (float)((BarcodeScannerActivity)_activity).mCameraSource.PreviewSize.Width) / (float)((BarcodeScannerActivity)_activity).mPreview.mSurfaceView.scaleNominatorY;

//관심영역 지정
if (!(item as Barcode).BoundingBox.Intersect(new Rect((int)left, (int)top, (int)right, (int)bottom)))
{
return;
}