UE4 The Evil Within Dope Effect

Tried to implement a similar effect in UE4 with scene capture and post processing. The idea is simple: capture the frame with scene capture component and render to a render texture. In post process material, lerp from the RT to current scene color over time. Don't forget to apply it before tone mapping. Otherwise it gets extremely dark because of gamma correction.
This is not strictly what I wanted to achieve. At the end of the video you'll notice that this technique cannot be triggered continuously (otherwise it looks like it's dropping frame). The reason is that it's not lerping from the frame buffer. It's reading from a scene capture instead, which does not keep information from previous frames. I'll try to change it so that it can actually read from frame buffer at some point.

Видео UE4 The Evil Within Dope Effect канала Unreal Xinda