New answers tagged photo-management
I'm not sure this is exactly what you're looking for, but you should be able to do a Windows search based on dimensions. Search for files smaller than the original images and then you should be able to remove them. That, of course, is assuming that you don't want to save any smaller files.
If you're asking for GUI-driven software, then please note that you probably will have to look harder. I do not know of any. Now, For What It Is Worth: ExifTool (a command line utility) will do what you have described. That is at least to the level that it will copy/move all images it can find THAT HAS METADATA (e.g. EXIF) into a location that may depend on ...
Darktable (which you can download for OSX here) is probably the software that comes closest to what you are looking for. The workflow still has some rough edges, compared to Lightroom or Aperture, but quite usable especially if you are looking for a scripting interface.
I would add DigiKam (KDE photograph management and editing tool) and LightZone (editing tool) to the list to examine.
Digikam has an SQLite database. I am not an SQL expert, but such databases allow for powerful search operations. While I do not have a direct answer, I am hoping the following avenues of research will be helpful. First start with Digikam's advanced search feature. Start with Browse->Search and activate the "Advanced Search ..." menu. Select the criteria ...
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