What do all the walls with secret switches look like?

Where a switch type appears on a wall is variable, so while the screenshots below circle what the switch looks like, it doesn't mean you can always look at exactly that part of the wall to see it.

Here are the hidden switch types I've seen.

Also, I have found secrets by doing the following:

• Placing torches in sconces
• Removing torches from sconces
• Finding pressure plates on the floors (which have always been very obvious)
• Placing desired item types in alcoves (such as putting a weapon in the alcove outside the room that says "no weapons allowed")
• Slicing tapestries hanging on walls to cut them down and reveal switches behind them.