Source video camera identification for multiply compressed videos originating from YouTube

The Photo Response Non-Uniformity is a unique sensor noise pattern that is present in each image or video acquired with a digital camera. In this work a wavelet-based technique used to extract these patterns from digital images is applied to compressed low resolution videos originating mainly from webcams. After recording these videos with a variety of codec and resolution settings, the videos were uploaded to YouTube, a popular internet video sharing website. By comparing the average pattern extracted from these resulting downloaded videos with the average pattern obtained from multiple reference cameras of the same brand and type, it was attempted to identify the source camera. This may be of interest in cases of child abuse or child pornography. Depending on the codec, quality settings and recording resolution, very satisfactory results were obtained.