Res-Dec: The Android Resistor Decoder

Res-Dec (the Resistor Decoder) is an Android application that automatically decodes color-coded resistors. The main goal of Res-Dec Application is to assist engineers, as well as others, with color blindness to accurately identify resistors that are labeled with the four color code system. To achieve this goal, the mobile computing platform based on Google’s Android OS was chosen for several reasons: 1) portability, 2) ubiquity, and 3) built-in digital camera and computing capacity. Most applications today only solve half of the problem: de-coding the value of the resistor by inputting the bands as options to the program. None of these applications, however, identify the value of the resistor automatically. The OpenCV library was ported to the Android platform and used as the underlying object recognition algorithm. A cascade of boosted classifiers working with haar-like features was trained with 246 images of different types of resistors. There are several milestones that the application must meet to be considered complete and functional. They are 1) onboard camera system initialization and image capture, 2) establishing the Region of Interest within the image captured, 3) previewing the picture to the user for confirmation, 4) identifying the color and order of the bands, and 5) calculating the value of the resistor. The first three milestones have been reached and a functional demo is available on the Android market. Future work includes reaching milestones four, five, and six, which should be complete by December 2012.