Barcode reader

Abstract

A barcode reader may include an image sensor array, an optic system, an image buffer, and a plurality of pre-processing circuits implemented in hardware. The optic system may be configured to focus an image of a barcode onto the image sensor array. The plurality of pre-processing circuits may collectively implement a plurality of different image processing functions. Each pre-processing circuit may be configured to receive as input an image frame from the image sensor array or an image data record from the image buffer. The image data record may be derived from the image frame. Each pre-processing circuit may also be configured to perform an image processing function with respect to the image frame or the image data record, thereby generating a new image data record. A decoder may use at least one image data record to decode the barcode.

What is claimed is: 
     
         1 . A barcode reader, comprising:
 an optic system for focusing an image of a barcode onto an image sensor array, wherein the image sensor array comprises a plurality of rows of pixels, and each pixel comprises an active photosensitive region which accumulates charge over a duration of an exposure period;   image read-out circuitry configured to:
 sequentially commence exposure for each row of pixels from a first row to a last row of the image sensor array, each row of pixels being exposed during an exposure period between an exposure start time for the row and an exposure end time for the row; and 
 for each row of pixels, at the exposure end time of the row, measure, and transfer either to pre-processing circuits or to memory, digital values representative of intensity of illumination accumulated on each pixel within the row during the exposure period, 
 wherein a time period exists during which the exposure start time has commenced for all rows and the exposure end time has not yet been reached for any row; and 
   a processor configured to decode the barcode represented by the digital values stored in the memory.