Over the last couple years, I’ve built a secure chat application on top of the public Twitter API that data-mines timelines to provide private communications. My solution was built using steganography, among other things. Recently I noticed that Twitter is post-processing the PNG files, which at first made sense because I saw the alpha channel was being stripped. Unfortunately, the alpha isn’t the only thing being changed and consequently the private data in my images is now being discarded.
Does anyone know of any way to avoid this post processing on uploaded media content?