I'm working on georeferencing old maps for archaeological purpose. Of course, colonial maps all do have some degree of transformation needed. But sometimes a specific region is well mapped while the neighbouring one is not. So I wonder if there is a way to calculate the amount of (in)accuracy, or the level to which the original image has been transformed in order to fit the actual landscape? Could a new raster be generated with these values? I'm using QGIS and TPS for georeferencing, but it can be on any platform.
I'm not sure if this is what you want but when you load a map with 4 or more calibration points in MAPC2MAPC, it calculates a best-fit affine transformation between coordinates and pixels - and then reports on how good the fit is.
If you have an image and a suitable calibration file it will only take seconds.
But what to do if the calibration is 'off' is another matter!
Load the maps shapefile from a trusted source and compare them. If there is some error it can be further improved by taking more control points, changing transformation parameters and trying a different datum.