Mood: The mood of the video appears to be romantic and nostalgic, with a sense of longing. The title 'O'Sanam' suggests a term of endearment, implying a deep emotional connection between two people. The overall theme seems to revolve around love and relationships.

Environment: The setting of the video seems to shift between different locations. The main image features a couple standing outdoors, possibly near a beach or a similar serene environment, indicated by the blurred background that suggests a natural setting. The black and white images inset show the same couple in what appears to be an urban or nighttime setting, adding a contrast to the overall scenic and possibly romantic locales.