The Data Protection Authority of Lower Saxony, Germany, has offered guidance on protecting data collected in the course of autonomous vehicle training.

• Training recordings may be processing of personal data if the pictures include faces or license plates which are recognizable.
• In order to effectively train the autonomous vehicle systems you need to collect training data that authentically represents situations cars would normally encounter. This is why real images must be collected. Pixelated images would not train the system properly.
• Legitimate interest may justify processing of image recordings collected in training of autonomous vehicle systems, provided that the conditions for this and other
  data protection requirements are met.
• It is important to properly balance the interests to this end. Consider, for example, the fact that the purpose of the processing is not identifying the individuals. A framework on this is currently being developed.

In addition to legal basis you also need to:

• Fulfill the transparency obligations by marking the vehicles,
• Conduct a privacy impact assessment
• Implement appropriate technical and organizational protective measures.