How to rectify the walls of buildings in PostGIS?

Question

I need an operations in PostGIS to eliminate intermediate vertexes in a polygon to rectify the walls of a building.

I was revising http://trac.osgeo.org/postgis/wiki/UsersWikiExamplesSpikeRemover but it only works to eliminate spikes.

example:

Answer 1

Applying a douglas-peucker filter with a small parameter value (like one meter) should remove these points. See ST_Simplify.