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Why is QR Code generation so slow on iOS?

Jun 29, 2014 at 10:44 PM
I use this library to produce QR codes on WP8, Android and iOS. On iOS this code takes several seconds to produce a QR code. Any idea why?
    var qrEncoder = new ZXing.BarcodeWriter
    {
        Format = ZXing.BarcodeFormat.QR_CODE,
        Options = new ZXing.Common.EncodingOptions
        {
            Width = 1080,
            Height = 1080,
        },
    };
    var bitmap = qrEncoder.Write(text); // this is the slow line 
Jul 1, 2014 at 8:56 PM
Sorry, I have no real idea and can't test it.
Perhaps you should use smaller values for width and height and scale the bitmap up after generating.
But I can't believe that it should make any difference.
Hopefully some other user of the library has an idea...
Jul 6, 2014 at 7:18 PM
Reducing the resolution sped it up significantly. I tried 128x128 but that was too blurry when I scaled it up to fill the iPhone screen. 256x256 seemed to provide an acceptable delay and clarity of screen.
But ya, it's weird that this low resolution is only required on iPhone.

--
Andrew Arnott
"I [may] not agree with what you have to say, but I'll defend to the death your right to say it." - S. G. Tallentyre