An Image Comparison API utilizing OpenCV provides a streamlined method for quantifying the similarity between two images. It processes inputs through image normalization, feature extraction, and the application of various similarity metrics like Structural Similarity Index (SSIM), Mean Squared Error (MSE), and histogram comparisons. Advanced feature matching techniques may also be employed for detailed analysis. The API returns a comprehensive set of similarity scores and, optionally, visual representations of comparison results, catering to diverse applications such as content verification, duplicate detection, and quality assurance across different industries.