18. The non-transitory computer-readable storage medium of claim 17 , wherein the processing device further to: apply a second predetermined set of rules to the electronic media item to identify a second set of regions, wherein a plurality of regions in the second set of regions is associated with a second region type; analyze one or more regions in the second set of regions to determine an additional typographical feature set for the second set of regions; perform a second cluster analysis based on the additional typographical feature set to identify a second cluster of regions; and update the second predetermined set of rules based on the second cluster analysis to generate a second updated set of rules; and apply the second updated set of rules to the electronic media item to identify one or more regions associated with the second region type.
17. A non-transitory computer-readable storage medium storing instructions which, when executed, cause a processing device to: apply a first predetermined set of rules to an electronic media item to identify a first set of regions, wherein a plurality of regions in the first set of regions is associated with a first region type, the first predetermined set of rules specifying a combination of typographical features used to identify the first region type; analyze one or more regions in the first set of regions to determine a typographical feature set for the one or more regions; perform, by the processing device, a cluster analysis to identify a first cluster of regions from the first set of regions, where a first typographical feature set of a first region in the first cluster and a second typographical feature set of a second region in the first cluster comprise values that are within a threshold of a desired value for the first cluster; update the first predetermined set of rules to account for typographical feature values determined from a centroid of the first cluster of regions to generate a first updated set of rules; and apply the first updated set of rules to the electronic media item to identify one or more regions associated with the first region type.