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For a quickstart for smart-cropped thumbnails using Azure AI Vision 4.0 API,in the documentation for the Image Analysis service. It includes setting up a basic application and utilize the API for image analysis, including cropping images intelligently.
Kindly refer the below document: https://learn.microsoft.com/en-us/azure/ai-services/computer-vision/quickstarts-sdk/image-analysis-client-library-40?tabs=visual-studio%2Cwindows&pivots=programming-language-csharp
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