OpenCFU, a New Free and Open-Source Software to Count Cell Colonies and Other Circular Objects
The medians of seven humans counts were used as a reference to measure deviation. The effect of the number of colonies on the deviation from the reference was assessed (A). For NICE and the ImageJ macro (IJM), the slope was significantly negative. The dotted line represents the reference. The absolute deviation from the reference was used as a measure of error (B). Error for the best human, the worst human and the three methods were compared to the pooled human group. With high-definition images (HD), NICE and IJM had a higher error than the pooled human group (Pool) while OpenCFU (OFU) did not. Using low-definition pictures (LD) from a low-cost webcam increased the error for the three methods.