Protection against reverse engineering in digital cameras

Over the past decade, a number of digital forensic techniques have been developed to authenticate digital signals. One important set of forensic techniques operates by estimating signal processing components of a digital camera´s signal processing pipeline, then using these estimates to perform forensic tasks such as camera identification or forgery detection. However, because these techniques are capable of estimating a camera´s internal signal processing components, these forensic techniques can be used for reverse engineering. In this paper, we propose integrating an anti-forensic module into a digital camera´s processing pipeline to protect against forensic reverse engineering. Our proposed technique operates by removing linear dependencies amongst an output images interpolated color values and by disrupting the color sampling grid. Experimental results show that our proposed technique can be effectively used to protect against the forensic reverse engineering of key components of a digital camera´s processing pipeline.