RuntimeException when decoding specific files

[ruimelodev]

I'm using BoofCV to decode QR codes.
When I run the decoder on specific files, I get a RuntimeException with error "An error occurred while calling o40.process":

py4j.protocol.Py4JJavaError: An error occurred while calling o40.process.
: java.lang.RuntimeException: Value out of range. value=54
        at boofcv.alg.fiducial.qrcode.QrCodeCodecBitsUtils.valueToAlphanumeric(QrCodeCodecBitsUtils.java:338)
        at boofcv.alg.fiducial.qrcode.QrCodeCodecBitsUtils.decodeAlphanumeric(QrCodeCodecBitsUtils.java:164)
        at boofcv.alg.fiducial.qrcode.QrCodeDecoderBits.decodeAlphanumeric(QrCodeDecoderBits.java:265)
        at boofcv.alg.fiducial.qrcode.QrCodeDecoderBits.decodeMessage(QrCodeDecoderBits.java:157)
        at boofcv.alg.fiducial.qrcode.QrCodeDecoderImage.decode(QrCodeDecoderImage.java:253)
        at boofcv.alg.fiducial.qrcode.QrCodeDecoderImage.process(QrCodeDecoderImage.java:100)
        at boofcv.abst.fiducial.QrCodePreciseDetector.process(QrCodePreciseDetector.java:89)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.base/java.lang.reflect.Method.invoke(Method.java:564)
        at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
        at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
        at py4j.Gateway.invoke(Gateway.java:282)
        at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
        at py4j.commands.CallCommand.execute(CallCommand.java:79)
        at py4j.GatewayConnection.run(GatewayConnection.java:238)
        at java.base/java.lang.Thread.run(Thread.java:832)

Here is an example of a file that throws exception:
pdf_invalid_2.pdf

[lessthanoptimal]

There are two things going on. 1) this appears to be an incorrectly encoded QR code. 2) This failure mode was not handled inside the decoder.

The reason I believe the QR code to be invalid is that after adding more debug logic it was discovered that it's specifying an Alphanumeric value of 54, which is outside the allowed range. As a sanity check I used my phone to try to read the QR code and tried 4 different apps and they all failed. At this point I think it's unlikely to be a logic error in the message decoder.

#376

There's the PR. It's going to under go a bit more testing before the updated logic is released.

[ruimelodev]

I'm aware it's an invalid QR code, sorry I didn't mention that before. The reason why I opened up an issue for it was because I was expecting the detector to return an empty result instead of throwing an exception.

I have another file where another exception is thrown with error An error occurred while calling o767.process.:

    raise Py4JJavaError(
    py4j.protocol.Py4JJavaError: An error occurred while calling o767.process.
: java.lang.NullPointerException: Cannot read field \"width\" because \"gray\" is null
    at boofcv.abst.fiducial.QrCodePreciseDetector.process(QrCodePreciseDetector.java:67)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:564)
    at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
    at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
    at py4j.Gateway.invoke(Gateway.java:282)
    at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
    at py4j.commands.CallCommand.execute(CallCommand.java:79)
    at py4j.GatewayConnection.run(GatewayConnection.java:238)
    at java.base/java.lang.Thread.run(Thread.java:832)

[lessthanoptimal]

Could you share the image so I can verify that it has been fixed? I'll do a small release in the next week or so to get these bug fixes out.

[ruimelodev]

Unfortunately, I can't replicate the second error, I only have that stack trace from my logs.