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doc/doc_sort_tool.md

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+### **Sort tool**:
+
+`blur` places most blurred faces at end of folder
+
+`hist` groups images by similar content
+
+`hist-dissim` places most similar to each other images to end.
+
+`hist-blur` sort by blur in groups of similar content
+
+`brightness` 
+
+`hue`
+
+`black` Places images which contains black area at end of folder. Useful to get rid of src faces which cutted by screen.
+
+`final` sorts by yaw, blur, and hist, and leaves best 1500-1700 images.
+
+Best practice for gather src faceset from tens of thousands images:
+
+1) `black` -> then delete faces cutted by black area at end of folder
+2) `blur` -> then delete blurred faces at end of folder
+3) `hist` -> then delete groups of similar unwanted faces and leave only target face
+4) `final` -> then delete faces occluded by obstructions
+
+Best practice for dst faces:
+
+1) delete first unsorted aligned groups of images what you can to delete. Dont touch target face mixed with others.
+2) `hist` -> then delete groups of similar and leave only target face