                                "default": "none",
                                "help": "R|Performing normalization can help the aligner better "
                                        "align faces with difficult lighting conditions at an "
                                        "extraction speed cost. Different methods will yield "
                                        "different results on different sets."
                                        "\nL|'none': Don't perform normalization on the face."
                                        "\nL|'clahe': Perform Contrast Limited Adaptive Histogram "
                                        "Equalization on the face."
                                        "\nL|'hist': Equalize the histograms on the RGB channels."
                                        "\nL|'mean': Normalize the face colors to the mean."})
 
</s> remove                               "help": "Draw landmarks on the ouput faces for "
                                      "debug"})
 </s> add                               "help": "Draw landmarks on the ouput faces for debugging purposes."}) </s> remove                               "help": "Reference images for the person you want to process. "
                                      "Should be a front portrait with a single person in the "
                                      "image. Multiple images can be added space separated. NB: "
                                      "Using face filter will significantly decrease extraction "
                                      "speed."})
 </s> add                               "help": "Optionally select people you wish to process by passing in "
                                      "an image of that person. Should be a front portrait with a "
                                      "single person in the image. Multiple images can be added "
                                      "space separated. NB: Using face filter will significantly "
                                      "decrease extraction speed and its accuracy cannot be "
                                      "guaranteed."})
        argument_list.append({"opts": ("-l", "--ref_threshold"),
                              "action": Slider,
                              "min_max": (0.01, 0.99),
                              "rounding": 2,
                              "type": float,
                              "dest": "ref_threshold",
                              "default": 0.4,
                              "help": "For use with the optional nfilter/filter files. Threshold "
                                      "for positive face recognition. Lower values are stricter. "
                                      "NB: Using face filter will significantly decrease "
                                      "extraction speed and its accuracy cannot be "
                                      "guaranteed."}) </s> remove                               "help": "Skip frames that already have "
                                      "detected faces in the alignments "
                                      "file"})
 </s> add                               "help": "Skip frames that already have detected faces in the "
                                      "alignments file"}) </s> remove                                       "speed cost."})
 </s> add                                       "speed/system RAM cost."}) </s> remove                               "help": "Reference image for the persons you do not want to "
                                      "process. Should be a front portrait with a single person "
                                      "in the image. Multiple images can be added space "
                                      "separated. NB: Using face filter will significantly "
                                      "decrease extraction speed."})
 </s> add                               "help": "Optionally filter out people who you do not wish to "
                                      "process by passing in an image of that person. Should be a "
                                      "front portrait with a single person in the image. Multiple "
                                      "images can be added space separated. NB: Using face filter "
                                      "will significantly decrease extraction speed and its "
                                      "accuracy cannot be guaranteed."})
                                      "different results on different sets. NB: This does not "
                                      "impact the output face, just the input to the aligner."
                                "default": "none",
                                "help": "R|Performing normalization can help the aligner better "
                                        "align faces with difficult lighting conditions at an "
                                        "extraction speed cost. Different methods will yield "
                                      "different results on different sets. NB: This does not "
                                      "impact the output face, just the input to the aligner."
                                        "\nL|'none': Don't perform normalization on the face."
                                        "\nL|'clahe': Perform Contrast Limited Adaptive Histogram "
                                        "Equalization on the face."
                                        "\nL|'hist': Equalize the histograms on the RGB channels."
                                        "\nL|'mean': Normalize the face colors to the mean."})
keep keep keep keep replace keep keep keep keep keep
 Clarification of helptext in cli.py 
lib/cli.py