Abstract: A system for digital barcode processing. A light reflected from a barcode is captured by a photodetector to produce a photocurrent. The photocurrent is converted to a voltage, amplified and filtered to produce a photovoltage. The photovoltage is differentiated to form a first derivative signal and the first derivative signal is converted to a digital first derivative signal and processed to identify logic transitions represented by the barcode. The processing system subjects the photosignal to Gaussian filtering and differentiates the digital first derivative signal to form a second derivative signal. The digital first derivative signal is compared against a positive and a negative threshold and the second derivative signal is examined to detect zero crossings.