ParaDISE - Parallel Distributed Image Search Engine. Based on Hadoop, probably offline processing.
Image Similarity service (github) - scala based image similarity service, declared to be scalable. Image storage and image similarity logic is implemented within independent, stateless micro-services. Data is stored in postgres. Clustering is based on histograms. 1 contributor. No tests. abandoned.
ViSense SDK for python - SDK for closed source image search
Deep Features - publish deep features extracted from datasets:
LIRE github, Project page, Documentation Java library that provides a simple way to retrieve images and photos based on color and texture characteristics. LIRE creates a Lucene index of image features for content based image retrieval (CBIR) using local and global state-of-the-art methods. Easy to use methods for searching the index and result browsing are provided. Best of all: it’s all open source.