The SDK is only necessary for customers that want to create a custom control interface to the camera. Many customers operate Tau2 and Quark2 cameras in an autonomous mode, that is, power in and video out only.The FLIR SDK integrates with most FLIR OEM Cameras, allowing customers the capability to integrate software that can communicate and perform camera functions. There are 2 main components that comprise the FLIR SDK:
The Windows Host SDK provides source code (C, C++), samples(C++, C# VB), and binaries (DLL`s) that aid customers in the development of camera integration software in a Microsoft Windows OS environment.
The Embedded Host SDK provides low level source code written in C, that allows the developer to integrate the SDK with the FLIR camera on a non-Windows OS. Standard driver interfaces are provided by the SDK source code, but the low level drivers (e,g UART) need to supplied by the developer.
This product is typically delivered directly to an internet location from which the software can be immediately downloaded after payment has been received.
Also refer to this question.