Leading Senior Constable Dr Janis Dalins is looking for 100,000 happy images of children – a toddler in a sandpit, a nine-year-old winning an award at school, a sullen teenager unwrapping a present at Christmas and pretending not to care. The search for these safe, happy pictures is the goal of a new campaign to crowdsource a database of ethically obtained images that Dalins hopes will help build better investigative tools to use in the fight against what some have called a "tsunami" of child sexual assault material online. Dalins is the co-director of AiLecs lab, a collaboration between Monash University and the Australian federal police, which builds artificial intelligence technologies for use by law enforcement. In its new My Pictures Matter campaign, people above 18 are being asked to share safe photos of themselves at different stages of their childhood. Once uploaded with information identifying the age and person in the image, these will go into a database of other safe images.

The dark web (also known as the deep, invisible and hidden web) with its veil of anonymity has been associated with crimes such as drug dealing, child pornography and credit card fraud. This dire reputation is difficult to confirm through research, as criminal sites can only be accessed legally by law enforcement officers conducting an investigation. But a recent study led by Monash University PhD candidate Janis Dalins – who also happens to be an Australian Federal Police (AFP) officer – has been able to shed light on the actual activity going on in the dark web's shadowy realms. Dalins' main academic supervisor, Dr Campbell Wilson, told create digital the PhD research was not originally focused on law enforcement, but Dalins' policing background offered a unique opportunity to develop tools to improve community safety online. "It became clear over time that we could bring Janis' experience in law enforcement together with research, particularly in machine learning," Wilson said.

The dark web is a difficult place to police. Comprising millions of websites shrouded in anonymity, it is an online playground for dangerous criminals and political plotters - anyone trying to evade authority or do the wrong thing. But one Australian Federal Police officer hopes to develop an artificially intelligent (AI) "crawler" that could scan the dark web for illegal activity and alert authorities to anything suspicious. If successful, the AI crawler would - for example - make it easier and faster to track down paedophiles, a task that at present is time-consuming and requires investigators to look at thousands of confronting images and material. The officer, Janis Dalins, has been developing the crawler as part of his PhD.