          # Prepare sort, group and final process method names
          _sort = "sort_" + self.args.sort_method.lower()
          _group = "group_" + self.args.group_method.lower()
          _final = "final_process_" + self.args.final_process.lower()
          self.args.sort_method = _sort.replace('-', '_')
          self.args.group_method = _group.replace('-', '_')
          self.args.final_process = _final.replace('-', '_')
  
          self.sort_process()
 
</s> remove                                       "\nL|'hist-dissim': Like 'hist' but sorts by "
                                      "dissimilarity."
 </s> add                                       "\nL|'hist-dissim': Like 'hist' but sorts by dissimilarity."
                                      "\nL|'color-gray': Sort images by the average intensity of "
                                      "the converted grayscale color channel."
                                      "\nL|'color-luma': Sort images by the average intensity of "
                                      "the converted Y color channel. Bright lighting and "
                                      "oversaturated images will be ranked first."
                                      "\nL|'color-green': Sort images by the average intensity of "
                                      "the converted Cg color channel. Green images will be "
                                      "ranked first and red images will be last."
                                      "\nL|'color-orange': Sort images by the average intensity "
                                      "of the converted Co color channel. Orange images will be "
                                      "ranked first and blue images will be last." </s> remove                                           "face-yaw", "hist", "hist-dissim"),
 </s> add                                           "face-yaw", "hist", "hist-dissim", "color-gray",
                                          "color-luma", "color-green", "color-orange"),
        if _sort.startswith('sort_color-'):
            self.args.color_method = _sort.replace('sort_color-', '')
            _sort = _sort[:10]
          # Prepare sort, group and final process method names
          _sort = "sort_" + self.args.sort_method.lower()
          _group = "group_" + self.args.group_method.lower()
          _final = "final_process_" + self.args.final_process.lower()
        if _sort.startswith('sort_color-'):
            self.args.color_method = _sort.replace('sort_color-', '')
            _sort = _sort[:10]
          self.args.sort_method = _sort.replace('-', '_')
          self.args.group_method = _group.replace('-', '_')
          self.args.final_process = _final.replace('-', '_')
  
          self.sort_process()
keep keep keep add keep keep keep keep keep
 Color channel sorting (#905)

* Add Sort by Color Feature

Sort by
 - Grayscale
 - Luma
 - Green to Red
 - Orange to Blue 
tools/sort.py