Search code examples
androidcamerazxingmode

ZXing on Android: how to set camera in negative mode?

I want to use zxing in an android project. I have download the code and the example app is running now (ZXingTestActivity). For your information, i am not very familiar with coding native android.

I want to use zxing to scan qr-codes to configurate an application. To avoid confusion between normal qrcodes and configuration qrcodes i want to print inverted/negative qrcodes on screen or paper.

To be able to scan these inverted/negative qrcodes, the camera must be in negative mode. How can i do this? I am not sure where to start, however....

In the ZXingTestActivity.java there is a clicklistener that specify some extra parameters to the IntentIntegrator, for example:

private final Button.OnClickListener scanProduct = new Button.OnClickListener() {
    @Override
    public void onClick(View v) {
      IntentIntegrator integrator = new IntentIntegrator(ZXingTestActivity.this);
      integrator.addExtra("SCAN_WIDTH", 800);
      integrator.addExtra("SCAN_HEIGHT", 200);
      integrator.addExtra("RESULT_DISPLAY_DURATION_MS", 3000L);
      integrator.addExtra("PROMPT_MESSAGE", "Custom prompt to scan a product");
      integrator.initiateScan(IntentIntegrator.PRODUCT_CODE_TYPES);
    }
  };

Is it possible to add camera settings with addExtra and how do i format this? Is it possible? Or is there another way to configurate the camera to inverted/negative mode?

Solution

  • I do not know if it completely impossible with ZXing but with ZBar it is possible!

    1. First download the ZBar android version on sourceforge: http://sourceforge.net/projects/zbar/files/AndroidSDK/

    2. Add project to eclipse

    3. Open CameraPreview.java

    4. Add a private var to the class:

      private Camera.Parameters mCameraParams;

    5. Add the following lines after the line: mCamera = camera; in the constructor CameraPreview:

      mCameraParams = camera.getParameters(); mCameraParams.setColorEffect(Camera.Parameters.EFFECT_NEGATIVE); mCamera.setParameters(mCameraParams);

    6. That's it! (run the project)

    Also think that ZBar is faster to detect damaged barcodes. Is the same as the PC-version i have used in another project and does the job very well. Blink with your eyes and the code is there. No fancy things at all, just good!