Project Oxford is a set of APIs that take advantage of Machine Learning to provide developers with

These technologies require Machine Learning, which requires a lot of computing power and a lot of data. Most of us have neither, but Microsoft does and has used it to create the APIs in Project Oxford.

Project Oxford provides APIs to analyze pictures and voice and provide intelligent information about them.

There are three broad categories of services: Vision, Voice, and Language.

The Vision APIs analyzes pictures and recognizes objects in those pictures.  For example, several Vision APIs are capable of recognizing  faces in an image. One analyzes each face and deduces that person's emotion; another can compare 2 pictures and decide whether or not 2 photographs are the same person; a third guesses the age of each person in a photo.

The Speech APIs can convert speech to text or text to speech. It can also recognize the voice of a given speaker (if you want to use that for authentication in your app, for example) and infer the intent of the speaker from his words and tone.

The Language APIs seem more of a grab bag to me. A spell checker is smart enough to recognize common proper names and homonyms.

All these APIs are currently in Preview but I've played with them and they appear very solid. Many of theme even provide a confidence factor to let you know how confident you should be in the value returned. For example, 2 faces may represent the same person but it helps to know how closely they match.

You can use these APIs. To get started, you need a Project Oxford account, but you can get one for free at

Each API offers a free option that restricts the number and/or frequency of calls, but you can break through that boundary for a charge.

You can also find documentation, sample code, and even a place to try out each API live in your browser at

You call each one by passing and receiving JSON to a RESTful web service, but some of them offer an SDK to make it easier to make that call from a .NET application.

You can see a couple of fun applications of Project Oxford at (which guesses the ages of people in photographs) and (which identifies the breed of dog in a photo).

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