A facility is provided for recognizing blank and nearly blank images. In
various embodiments, the facility receives an indication of an image,
creates an analysis image based on the received image by detecting edges,
determines an edge ratio for the analysis image, determines whether the
edge ratio exceeds a threshold and, when the edge ratio does not exceed
the threshold, identifies the received image as a blank image. The
facility can include an edge detector component that creates an analysis
image based on a selected image by detecting edges in the selected image,
a calculator component that calculates an edge ratio for the analysis
image, and an analysis component that determines whether the calculated
edge ratio exceeds a threshold.