Forensics of High Quality and Nearly Identical JPEG Image Recompression
Cecilia Pasquini, Pascal Schöttle, Rainer Böhme, Giulia Boato, Fernando Pérez‐González · 2016
We address the known problem of detecting a previous compression in JPEG images, focusing on the challenging case of high and very high quality factors (>= 90) as well as repeated compression with identical or nearly identical quality factors. We first revisit the approaches based on Benford--Fourier analysis in the DCT domain and block convergence analysis in the spatial domain. Both were originally conceived for specific scenarios. Leveraging decision tree theory, we design a combined approach complementing the discriminatory capabilities. We obtain a set of novel detectors targeted to high quality grayscale JPEG images.