Amazon Machine Images (AMIs) now support tag-on-create and tag-based access control

Amazon EC2 now allows you to add tags to your Amazon Machine Images (AMIs) and EBS Snapshots during AMI creation. Tags are simple key-value pairs that you can assign to resources to easily organize, search, and identify resources, create cost allocation reports, and control access to resources. You can define fine-grained access controls using tags and AWS Identity and Access Management (IAM) policies to control access to resources and actions.  

Source:: Amazon AWS