Today, virtually every item on the market is labeled with at least one form of barcode, generally a flavor of either the EAN or the UPC standards. The success of barcode technology for identification, tracking, and inventory derives from its ability to encode information in a compact fashion with low associated cost.
Barcode reading via dedicated scanners is a mature technology. Commercial laser-based hand-held barcode scanners achieve robust reading with a reasonable price tag. Recently, there has been growing interest in accessing barcodes also with regular cellphones, without the need for a dedicated device. Indeed, a number of cellphone applications (apps) have appeared that provide access via barcode reading to the full characteristics of and user reviews for a product found at a store.
Unfortunately, images taken by cellphone cameras are often of low quality. Many cellphone cameras on the market are equipped with low-grade lenses, often lacking focusing capability, which often produce blurred images. Few cellphones have a flash and, therefore, motion blur and noise can be expected with low ambient light. All of these factors, possibly combined with low image resolution, make barcode reading difficult in certain situations. Indeed, all existing image-based barcode readers have limited performance when it comes to images taken in difficult light conditions, or when the camera is not close enough to the barcode. To improve accuracy, barcode reading apps usually prompt the user to precisely position the camera to ensure that the barcode covers as much of the frame as possible. This operation can be somewhat bothersome, as it requires a certain amount of interaction with the user, who needs to frame the barcode correctly using the viewfinder.
This invention presents new techniques for barcode reading advancing the art and overcoming at least some of the current problems or shortcomings with existing barcode reading techniques.