Image similarity calculation method and device and similar image retrieval method and system

The invention discloses an image similarity calculation method and device and a similar image retrieval method and system. The image similarity calculation method comprises the steps that a query image and a reference image are adaptively segmented respectively; for each small block of the query image, a small block of the reference image is determined as the matched small block of the small blockof the query image; and according to the similarity between each small block of the query image and the matched small block, the similarity between the query image and the reference image is determined. According to the invention, images in a database do not need to be trained in advance; the accuracy is high; the accuracy and immediacy of image similarity retrieval are taken into consideration;and the image similarity calculation method and device and the similar image retrieval method and system are suitable for image similarity retrieval scenes such as real-time video content matching. 本发明公开种图像相似度计算方法和装置、相似图像检索方法和