Method and system for automatically counting microbial colonies

The present disclosure is directed to an automated method for evaluating growth on plated media, comprising: providing a culture media inoculated with a biological sample (202); incubating the inoculated culture media (204); following incubation, obtaining a first image of the inoculated media at a first time (206); after further incubation, obtaining a second image of the inoculated media at a second time (206); aligning the first image with the second image, such that the coordinates of a pixel in the second image are about the same as the coordinates of a corresponding pixel in the first image; comparing image features of the second image with image features of the first image; classifying image features of the second image as colony candidates based on image feature changes from the first time to the second time; for colony candidates determined to be from a common microorganism in the biological sample inoculated on the culture media, counting said colony candidates;and determining whether the number of counted colonies meets or exceeds the threshold count value stored in memory and indicative of significant growth.