Detecting barcode using android camera

I am currently developing this Android phone application for the visually impaired people to detect and scan barcode. I am going to use ZXing(scanning via intent) for decodi开发者_Python百科ng barcode.

The problem now is, I need to use the camera to detect the presence of barcode around scanning region and alert the user via vibration or speech synthesizer. I am kind of stuck in this area now, I have tried borrowing books from the library and google searching for edge detection example, but to no avail:(

Can any kind soul please give me some advice in this area?

Thanks in advance!

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There are other scanners on the market that use the full picture to detect barcodes. I know that NeoReader does not have this kind of scanning region.

It may be easier to find an API for different scanner then to detect barcodes (don't forget to focus...). Even if you find a way to detect codes, you still have to guide the visually impaired people to move the mobile so that the code will be inside the scanning area.