Air carrier Captain reported a labeling error of the DG parcels which were wrapped with non-transparent plastic.

Narrative

Upon boarding the airplane I glanced in the back to see how much was loaded and noticed that the Hazardous Goods were loaded and covered with heavy non-transparent plastic. The DG was labeled on top of the plastic with sticky notes" since you could not see through the plastic. I asked the ramp agent for a DG representative and she volunteered that she was qualified. I pointed out to her the FOM reference XX.XX spelling out our duties as the inspecting crew. I explained and she agreed that we could not comply with FOM as the pallet was loaded. I asked her to let me know what their plan was to correct it. The pallets did not originate in ZZZZ; they were from ZZZZ1. I notified Dispatch and asked him to advise the Supervisor. DG at ZZZZ decided to undress the pallet to allow for inspection rather than remove the pallets. Once complete they recovered the pallets and we departed. Cause: Incorrect/unsafe DG procedures during pallet build up at ZZZZ1 (originating ramp). Non-transparent plastic used to cover DG. Excess plastic during covering.Crew acceptance of non-acceptable/unsafe DG pallets.Suggestions: Adherence to correct DG procedures during pallet buildup. Use of transparent plastic.Crews adhering to DG procedures outlined in FOM and not accepting non-compliant pallets. The ramps will continue to produce this kind of work unless the crew holds the standard."