A system and method of identifying cognate image sequences is disclosed that examines significant frames of a stream of video images using an array of image indexes. The image index array includes image indexes obtained by at least two different image indexing methods. These are compared to a corresponding array of image indices of significant frames of known image sequences. An image quality indicator is used to determine which set of image index thresholds to use in making the comparison. These thresholds are more stringent for higher quality frames. Two image sequences are considered cognate when a string of sufficiently many sequential frame matches is established. In an alternate embodiment, image blurriness is also, or instead, used to determine the appropriate set of image index thresholds. The sets of image index thresholds are determined using machine learning on a curated set of representative images.