Denoising video content includes identifying a three-dimensional flat frame block of multiple frames of the video content, wherein the three-dimensional flat frame block comprises flat frame blocks, each flat frame block is located within a respective frame of the multiple frames, and the flat frame blocks have a spatial and temporal intensity variance that is less than a threshold. Denoising video content also includes determining an average intensity value of the three-dimensional flat frame block, determining a noise model that represents noise characteristics of the three-dimensional flat frame block, generating a denoising function using the average intensity value and the noise model, and denoising the multiple frames using the denoising function.