MediaSDK implements a multimedia encode/decode API that utilizes Intel HD Graphics hardware acceleration and SIMD processor acceleration to implement multimedia codecs. To get a full description check the MediaSDK web site and forums. Here are a few links to get you started:
When Intel HD Graphics are not available, MediaSDK utilizes functions from the Intel IPP library to implement its multimedia codecs. When you use the MediaSDK you employ the MediaSDK API, not the IPP API, so the use of the IPP library is "hidden" from view.
The Intel IPP library provides a large collection of low-level "primitives" or "kernels" that utilize the CPU SIMD instructions (MMX, SSE, AVX, etc.) to accelerate performance of those functions. These primitive functions can be used to implement algorithms for audio and video codecs as well as implementing cryptography, data compression, string manipulation and other algorithms, including many common signal processing tasks.
The Intel IPP library includes a collection of samples, including the UMC multimedia class library, that show how these low-level primitives can be used to implement common algorithms. Keep in mind that the samples are not complete, but can be used as a starting point to build your own custom application built on the IPP library.