Make --upsample a parameter for command line face_recognition

Otherwise smaller faces can't be located via command line

face_recognition/face_detection_cli.py

@@ -14,9 +14,9 @@ def print_result(filename, location):
     print("{},{},{},{},{}".format(filename, top, right, bottom, left))
 
 
-def test_image(image_to_check, model):
+def test_image(image_to_check, model, upsample):
     unknown_image = face_recognition.load_image_file(image_to_check)
-    face_locations = face_recognition.face_locations(unknown_image, number_of_times_to_upsample=0, model=model)
+    face_locations = face_recognition.face_locations(unknown_image, number_of_times_to_upsample=upsample, model=model)
 
     for face_location in face_locations:
         print_result(image_to_check, face_location)
@@ -26,7 +26,7 @@ def image_files_in_folder(folder):
     return [os.path.join(folder, f) for f in os.listdir(folder) if re.match(r'.*\.(jpg|jpeg|png)', f, flags=re.I)]
 
 
-def process_images_in_process_pool(images_to_check, number_of_cpus, model):
+def process_images_in_process_pool(images_to_check, number_of_cpus, model, upsample):
     if number_of_cpus == -1:
         processes = None
     else:
@@ -42,6 +42,7 @@ def process_images_in_process_pool(images_to_check, number_of_cpus, model):
     function_parameters = zip(
         images_to_check,
         itertools.repeat(model),
+        itertools.repeat(upsample),
     )
 
     pool.starmap(test_image, function_parameters)
@@ -51,7 +52,8 @@ def process_images_in_process_pool(images_to_check, number_of_cpus, model):
 @click.argument('image_to_check')
 @click.option('--cpus', default=1, help='number of CPU cores to use in parallel. -1 means "use all in system"')
 @click.option('--model', default="hog", help='Which face detection model to use. Options are "hog" or "cnn".')
-def main(image_to_check, cpus, model):
+@click.option('--upsample', default=0, help='How many times to upsample the image looking for faces. Higher numbers find smaller faces.')
+def main(image_to_check, cpus, model, upsample):
     # Multi-core processing only supported on Python 3.4 or greater
     if (sys.version_info < (3, 4)) and cpus != 1:
         click.echo("WARNING: Multi-processing support requires Python 3.4 or greater. Falling back to single-threaded processing!")
@@ -59,11 +61,11 @@ def main(image_to_check, cpus, model):
 
     if os.path.isdir(image_to_check):
         if cpus == 1:
-            [test_image(image_file, model) for image_file in image_files_in_folder(image_to_check)]
+            [test_image(image_file, model, upsample) for image_file in image_files_in_folder(image_to_check)]
         else:
-            process_images_in_process_pool(image_files_in_folder(image_to_check), cpus, model)
+            process_images_in_process_pool(image_files_in_folder(image_to_check), cpus, model, upsample)
     else:
-        test_image(image_to_check, model)
+        test_image(image_to_check, model, upsample)
 
 
 if __name__ == "__main__":