barcode readers using the camera device in mobile phones

Barcode Readers using the Camera Device in Mobile

Phones

指導教授：張元翔 老師學生：吳思穎 99770032011/05/25

Introduction

Baseband processor ： works for voice digital signal processing, protocol control, power management and fundamental functions.

Application processor ： works for extra application such as movie codec, still photo codec and resizing, and other extra applications.

Introduction

Systems

Execute the barcode reader application

Capture from embedded camera device

Process the image in DSP

Decode the code

Display the results

Systems

Algorithms

Pre-processing

Corner marks detection

Fourth corner estimation

Inverse perspective transformation

Scanning of code

Algorithms

Pre-processing ：1. Histogram calculation to define the threshold

of black-white boundaries.2. Resizing of original image to reduce the

calculation costs.3. Recognizing QR-code area, and the filtering

for the area dilatation.

Algorithms

Corner marks detection ：

Algorithms

Fourth corner estimation ：

Algorithms

Inverse perspective transformation ：

Algorithms

Algorithms

Implementations&

Experimental Results

Implementations &Experimental Results

Thank you for your attention !!!