.pgm maps compare

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how to compare two .pgm maps

robot works well base on a map which generated by carto or gmapping, but someone change the environment ( some fixed objects) someday, how to detect the changes happens? you know robot works badly if the maps changes can cause the localization error and navigation error.

maybe we can get new map always, and then compare the new maps with the original one (we think that is the groundtruth)

but how to detect the changes?