android + ZXing barcode scanning library - custom size & orientation

Question

i've succeeded using the ZXing barcode scanning library , but only on landscape mode.

i've also succeeded setting the camera preview to be on portrait mode AND show it correctly (without stretching) , but now the barcode doesn't work at all . here're the changes i've made to "setDesiredCameraParameters" on "CameraConfigurationManager.java" in order to show the camera correctly :

void setDesiredCameraParameters(Camera camera)
{
    Camera.Parameters parameters = camera.getParameters();
    Log.d(TAG, "Setting preview size: " + cameraResolution);
    setFlash(parameters);
    setZoom(parameters);
    camera.setDisplayOrientation(90);
    parameters.set("rotation", 90);
    parameters.setPreviewSize(cameraResolution.y, cameraResolution.x);
    camera.setParameters(parameters);
}

i've tried some solutions mentioned on other places , but either they don't work , or they work but cannot show the camera preview correctly . examples: How to use Zxing in portrait mode? http://code.google.com/p/zxing/issues/detail?id=178#c46 https://github.com/pplante/zxing-android/issues

when i'm finished with that , i also need to customize the location&size of the rectangle to the scanning . i know that i need to change "setManualFramingRect" on "CameraManager.java" , but i'm not sure if i do it correctly . here's the code for that:

public void setManualFramingRect(Rect rect)
{
    if (initialized)
    {
        Point screenResolution = configManager.getScreenResolution();
        if (rect.right >= screenResolution.x)
            rect.right = screenResolution.x - 1;
        if (rect.left < 0)
            rect.left = 0;
        if (rect.bottom >= screenResolution.y)
            rect.bottom = screenResolution.y - 1;
        if (rect.top < 0)
            rect.top = 0;
        framingRect = rect;
        Log.d(TAG, "Calculated manual framing rect: " + framingRect);
        framingRectInPreview = null;
    }
    else
        _requestedFramingRect = new Rect(rect);
}

of course ,i've changed "openDriver" to call :

if (_requestedFramingRect != null)
    setManualFramingRect(_requestedFramingRect);

please help me.

EDIT: now i've found out that it doesn't work on some devices . it crashes on the beginning , and if you debug , you can see that even the preview doesn't work well.

i think the next post could answer my question: http://stackoverflow.com/questions/16252791/how-to-show-zxing-camera-in-portrait-mode-android/16252917#16252917 . however, since there was a long time since i've tested the zxing library, i don't know how well it works. — android developer, Apr 27 '13 at 14:25

score 2 · Answer 1 · answered Apr 12 '12 at 12:43

2

There's more to it than this. For example you need to actually "rotate" the camera data (or, scan it as if it's vertical) when the camera orientation is not the same as the device orientation. And when using a front camera, you need to account for the fact that its rotation is reversed.

answered Apr 12 '12 at 12:43

Sean Owen

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i tried the link i've already written about - it didn't work . do you know of someone who has succeeded doing it? – android developer Apr 12 '12 at 19:50
Yes, I did: https://play.google.com/store/apps/details?id=com.srowen.bs.android – Sean Owen Apr 12 '12 at 23:52
well i meant if anyone could share the solution to this problem (without cost) . :) – android developer Apr 13 '12 at 08:14
in any case , i don't understand why i need to rotate the input image ,since qr codes can be read no matter what is the orientation. – android developer Apr 13 '12 at 23:53
Yes, QR codes are fine in any rotation. 1D is not, if you're scanning horizontally. – Sean Owen Apr 14 '12 at 05:14
then why after my modifications without the data rotation(and with it, for that matter) , it won't work and find the qr code? is there something missing that i can't find? – android developer Apr 14 '12 at 07:48

android + ZXing barcode scanning library - custom size & orientation

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