Anonymizing photos of the violent ones is therefore likely to support their actions by making accountability less likely. To scrub ethically, limit it to the non-violent protestors. To support non-violence, better to help identify the violent people -- police or civilian -- the opposite of anonymizing them.
In a situation where police feel justified to kill extra-judicially over a possibly fake 20 dollar bill, what hope do we have that protesters won't be targeted in unfair ways? Or worse, that organizers won't be hunted down like animals and murdered like in Furguson? It would be unethical to not do everything in your power to protect those in this position.
secondly how do you plan to identify violent vs non-violent protesters from a static image? How would you find their identity afterwards? There is overwhelming evidence to suggest these methods are at best ineffective and at worst racist, and in either case will lead to innocent people being charged.
https://www.newscientist.com/article/2109887-police-mass-fac...
that's exactly what the murderers want to achieve