Cinemadrape is described as 'CinemaDrape helps you focus on your current task on the screen (such as a video in a web page, a photo or a document editor area) by instantly blanking or dimming the other less important areas in a web page or in the background windows'. There are five alternatives to Cinemadrape for Windows and Mac. The best alternative is HazeOver. It's not free, so if you're looking for a free alternative, you could try LeDimmer or Zorro. Other great apps like Cinemadrape are TunnelVision (Free, Open Source) and psKino (Free, Open Source).
Too many windows to manage? Big display? Or getting lost in multiple monitors? HazeOver is for you! ? TRIAL version: HazeOver.com Get rid of distractions and focus on your current task. HazeOver automatically highlights the front app window by dimming all background windows.
Zorro is a utility to completely blank the screen except for a rectangular area selected by the user. This is especially useful for watching videos on your computer without being distracted by other programs.