I have searched a lot to know how can we test an object exist in an image. I am searching for the name of the scientific/ technology that can provide this. As an example I can mention Instagram where you upload an image and Instagram writes: This image may contain sea, people, car. Is this content based image retrieval? Do I need local feature extraction for it? Are they based on deep learning or do they work by something like SIFT?
Whatever I studied was just able to receive a query image and search a database to say that which image is "similar" to that, not which image contains it.
Yeah it uses the technique of deep learning where they train their model to recognize number of objects in an image using either bounding box approach or multilabel classification. If a new image is passed to the model, it'll predict label of all the objects present in that image.