OpenCV - OpenCV is the world's biggest computer vision library
Social Mapper - A Social Media Enumeration & Correlation Tool by Jacob Wilkin(Greenwolf) - Greenwolf/social_mapper
Microsoft Computer Vision API - Extract rich information from images and analyze content with Computer Vision, an Azure Cognitive Service.
Truein Staff Attendance - Truein Staff Attendance is a software that offers services to companies in touchless face recognition based on employee attendance.
Amazon Rekognition - Add Amazon's advanced image analysis to your applications.
Kairos - Facial recognition & mood detection API