초록 ▼

Methods and associated apparatus are provided to analyze and selectively sample scan reflectance profile (SRP) signals by producing corresponding first derivative and second derivative signals, as the SRP signal is generated. The methods employ the occurrences of zero crossings of the first and or s

Methods and associated apparatus are provided to analyze and selectively sample scan reflectance profile (SRP) signals by producing corresponding first derivative and second derivative signals, as the SRP signal is generated. The methods employ the occurrences of zero crossings of the first and or second derivative signals, along with occurrences of the level of the first derivative signal rising above, or dropping below, predefined positive or negative threshold levels, respectively. Sample values, including positive and negative peak sample values, are produced and made available for post processing to determine one or more figures of merit (or quality parameters) that are indicative of the quality of a bar code indicia that was scanned to generate the SRP signal analyzed and processed.

대표청구항 ▼

[ What is claimed is:] [1.] A method to analyze and sample a scan reflectance profile signal to determine the level of all positive peaks and all negative peaks occurring therein, the method comprising the steps of:(a) producing a first derivative signal of the scan reflectance profile signal as the

[ What is claimed is:] [1.] A method to analyze and sample a scan reflectance profile signal to determine the level of all positive peaks and all negative peaks occurring therein, the method comprising the steps of:(a) producing a first derivative signal of the scan reflectance profile signal as the scan reflectance profile signal is generated;(b) determining one of:(i) when the level of the first derivative signal has risen above a predefined first threshold level, and(ii) when the Level of the first derivative signal has dropped below a predefined second threshold level;(c) producing a sample value representative of a peak level of the scan reflectance profile signal at the occurrence of a first zero crossing of the first derivative signal following the occurrence of one of step (b)(i) and step (b)(ii);(d) storing the sample value produced in step c; and(e) repeating steps b, c, and d until all portions of the scan reflectance profile signal have been analyzed;(f) the occurrence of each zero crossing of step (c) indicating the occurrence of a peak value within the scan reflectance profile signal, with the level of each peak value captured, sampled, and stored, being available for possible post processing to determine at least one figure of merit associated with the scan reflectance profile signal analyzed.