Digital trickery: how to spot altered photos and videos

Social media and newspapers and TV are increasingly susceptible to fake images. Thanks to digital technologies, manipulating video and photos is quite simple and affordable for anyone. An important part of journalistic work must therefore be dedicated to verifying the authenticity of video and "amateur" photographs that make news: understanding where they come from, who made them and especially when they were made is essential to prevent public opinion being confused or deceived. In short, how can one distinguish between true and false images? Examples will be given of sensational fakes and the techniques needed to spot them.