AMD FidelityFX Contrast Adaptive Sharpening (CAS) provides a mixed ability to sharpen and optionally scale an image.

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Xbox developer?

An example use of AMD FidelityFX Contrast Adaptive Sharpening exists within the Xbox Game Development Kit samples. 


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Open source, MIT license

AMD FidelityFX Contrast Adaptive Sharpening (CAS) provides a mixed ability to sharpen and optionally scale an image. The algorithm adjusts the amount of sharpening per pixel to target an even level of sharpness across the image. Areas of the input image that are already sharp are sharpened less, while areas that lack detail are sharpened more. This allows for higher overall natural visual sharpness with fewer artifacts.

CAS was designed to help increase the quality of existing Temporal Anti-Aliasing (TAA) solutions. TAA often introduces a variable amount of blur due to temporal feedback. The adaptive sharpening provided by CAS is ideal to restore detail in images produced after TAA .

CAS’ optional scaling capability is designed to support Dynamic Resolution Scaling (DRS). DRS changes render resolution every frame, which requires scaling prior to compositing the fixed-resolution User Interface (UI). CAS supports both up-sampling and down-sampling in the same single pass that applies sharpening.


A great example of this is moon surfaces. They have craters, surface rings, mountain ranges, and flat areas that have large contrast differences by design. CAS really shines in this situation, where it successfully allows for the subtle details created by the artists to become clearer in the final render, even with the existing post-processes turned on.

See AMD FidelityFX CAS in action with Godfall

Watch "Radeon RX 6000 Partner Showcase - Godfall and Counterplay Games" on YouTube in a new window

You'll also find AMD FidelityFX CAS in The Riftbreaker

The Riftbreaker
Watch "Radeon RX 6000 Partner Showcase - The Riftbreaker and EXOR Studios" on YouTube in a new window

Developers using AMD FidelityFX

FidelityFX CLI

Want to quickly try out FidelityFX Super Resolution (FSR) or FidelityFX Contrast Adaptive Sharpening (CAS)?

You can use our new command-line tool FidelityFX CLI, which lets you test FSR or CAS on a screenshot, or any other image.

Unreal Engine developer?

We have many powerful patches for Unreal Engine for registered Unreal Engine developers, covering performance and features.

FidelityFX Contrast Adaptive Sharpening is available as a feature patch you can apply for Unreal Engine.

A set of guidelines for developers on how to present options in the game’s user interface to enable/disable AMD FidelityFX Effects.

Find out what developers are saying about AMD FidelityFX.

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