When a conductor walks through the train to ask for tickets, the commuter should have their activated digital ticket displayed and show their smartphone screen to the conductor. The conductor will visually inspect the mobile ticket, which incorporates digital anti-counterfeiting features.
how can you do this? I am surprised by the visual part, if it had a QR code or similar then it's trivial crypto but visual? Say, it shows an animation, well, just capture it as a movie. If it shows an animation over your photo, then take the original photo and substract it and add back another photo. I just can't even imagine how this could work. Where could I read more?
Edit: after reading the first answer, sorry, the motivation behind this question is the botched up launch of the Budapest online pass sales system so expect the financial motivation to definitely be there. We are talking of something with a value of like 10% of the average net monthly salary. I only used the New Haven tickets as an explanation of the problem, as the press release describes the system real nicely.