Recently, I tried the ZBar SDK 0.1 for Android. Tried to scan on a printed QR Code (Version 8; ECC is L) of physical size 2.7cm x 2.7cm via thermal printer, but it failed to scan. However, after I scanned the printed QR code became a soft-copy image into PC and used any photo editing tool to "sharpen" the image and re-printed the QR code again with laser printer, then ZBar was able to scan it.
I have tried to user ZXing scanner to scan the original printed QR code via thermal printer, it was able to return the result immediately.
Just a question, does the ZBar SDK has "image sharpening" feature so that the scanned image is sharpened before move to decoding process?
I hope there is a solution for this.