Rapid and Reliable Detection of Film Grain Noise

The knowledge of material specific film grain characteristics can significantly improve the performance of digital film processing algorithms. This paper proposes a rapid and reliable detector for film grain properties. First, homogeneous blocks concerning intensity and texture are determined by a novel measure calculated in the frequency domain. Second, based on these blocks the signal-dependent grain noise level is estimated and an image region of pure film grain is detected. Evaluation based on a wide range of structured images with high frequent electronic noise and low frequent film grain, shows that the method performs with a worst case estimation error of 2.54 dB in typical movie quality (PSNR of 25-40 dB). This meets the requirements of real applications such as digital film restoration and special effects compositing.