I think that a similar technological innovation was key during the civil rights movement in the US in the 60s. Capturing the cruelty of racists against blacks in America and showing it on television was crucial for turning public opinion in favor of civil rights.
filming will do nothing till the the protections afforded the police by their union and local politicians; don't let these mayors fool anyone as most had budget increases planned for their cops; are made illegal. every violent act committed by any police officer must have the possibility of assault charges for the officer unless video clears them. any time the police must make a payout for an act committed by an officer that officer must be released and have their permanent record flagged so they just don't walk across state lines.
the only real national database we need is of government employees, be they cops, firemen, teachers, or clerk. get busted and you are done for nationwide with regards to public service.
Societies attitudes are very persistent. Takes decades for things to materially change. The root of that is the Max Plank quote: A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather its opponents eventually die, and a new generation grows up that is familiar with it.
That said I think juries are becoming much more aware of the implications of letting bad cops off the hook. Muni's are becoming tired of paying out settlements for cops that should have been long since fired. And this is in the contexts of increasing militarization of the police while the crime rate has been falling persistently for 30 years.
Things always look like they'll never change and then they do.