face detection algo, configurability, reusability

Try to move the crop in the direction of a face if it is present

More internal configuration options for choosing weights of each of the algorithm's findings

Move logic into its module

1 files changed, 216 insertions, 0 deletions

diff --git a/modules/textual_inversion/autocrop.py b/modules/textual_inversion/autocrop.py
new file mode 100644
index 00000000..f858a958
--- /dev/null
+++ b/modules/textual_inversion/autocrop.py
@@ -0,0 +1,216 @@
+import cv2
+from collections import defaultdict
+from math import log, sqrt
+import numpy as np
+from PIL import Image, ImageDraw
+
+GREEN = "#0F0"
+BLUE = "#00F"
+RED = "#F00"
+
+def crop_image(im, settings):
+  """ Intelligently crop an image to the subject matter """
+  if im.height > im.width:
+      im = im.resize((settings.crop_width, settings.crop_height * im.height // im.width))
+  else:
+      im = im.resize((settings.crop_width * im.width // im.height, settings.crop_height))
+
+  focus = focal_point(im, settings)
+
+  # take the focal point and turn it into crop coordinates that try to center over the focal
+  # point but then get adjusted back into the frame
+  y_half = int(settings.crop_height / 2)
+  x_half = int(settings.crop_width / 2)
+
+  x1 = focus.x - x_half
+  if x1 < 0:
+      x1 = 0
+  elif x1 + settings.crop_width > im.width:
+      x1 = im.width - settings.crop_width
+
+  y1 = focus.y - y_half
+  if y1 < 0:
+      y1 = 0
+  elif y1 + settings.crop_height > im.height:
+      y1 = im.height - settings.crop_height
+
+  x2 = x1 + settings.crop_width
+  y2 = y1 + settings.crop_height
+
+  crop = [x1, y1, x2, y2]
+
+  if settings.annotate_image:
+    d = ImageDraw.Draw(im)
+    rect = list(crop)
+    rect[2] -= 1
+    rect[3] -= 1
+    d.rectangle(rect, outline=GREEN)
+    if settings.destop_view_image:
+      im.show()
+
+  return im.crop(tuple(crop))
+
+def focal_point(im, settings):
+    corner_points = image_corner_points(im, settings)
+    entropy_points = image_entropy_points(im, settings)
+    face_points = image_face_points(im, settings)
+
+    total_points = len(corner_points) + len(entropy_points) + len(face_points)
+
+    corner_weight = settings.corner_points_weight
+    entropy_weight = settings.entropy_points_weight
+    face_weight = settings.face_points_weight
+
+    weight_pref_total = corner_weight + entropy_weight + face_weight
+
+    # weight things
+    pois = []
+    if weight_pref_total == 0 or total_points == 0: 
+      return pois
+
+    pois.extend(
+      [ PointOfInterest( p.x, p.y, weight=p.weight * ( (corner_weight/weight_pref_total) / (len(corner_points)/total_points) )) for p in corner_points ]
+    )
+    pois.extend(
+      [ PointOfInterest( p.x, p.y, weight=p.weight * ( (entropy_weight/weight_pref_total) / (len(entropy_points)/total_points) )) for p in entropy_points ]
+    )
+    pois.extend(
+      [ PointOfInterest( p.x, p.y, weight=p.weight * ( (face_weight/weight_pref_total) / (len(face_points)/total_points) )) for p in face_points ]
+    )
+
+    if settings.annotate_image:
+      d = ImageDraw.Draw(im)
+
+    average_point = poi_average(pois, settings, im=im)
+
+    if settings.annotate_image:
+      d.ellipse([average_point.x - 25, average_point.y - 25, average_point.x + 25, average_point.y + 25], outline=GREEN)
+      
+    return average_point
+
+
+def image_face_points(im, settings):
+    np_im = np.array(im)
+    gray = cv2.cvtColor(np_im, cv2.COLOR_BGR2GRAY)
+    classifier = cv2.CascadeClassifier(f'{cv2.data.haarcascades}haarcascade_frontalface_default.xml')
+
+    minsize = int(min(im.width, im.height) * 0.15) # at least N percent of the smallest side
+    faces = classifier.detectMultiScale(gray, scaleFactor=1.05,
+      minNeighbors=5, minSize=(minsize, minsize), flags=cv2.CASCADE_SCALE_IMAGE)
+
+    if len(faces) == 0:
+      return []
+
+    rects = [[f[0], f[1], f[0] + f[2], f[1] + f[3]] for f in faces]
+    if settings.annotate_image:
+      for f in rects:
+        d = ImageDraw.Draw(im)
+        d.rectangle(f, outline=RED)
+    
+    return [PointOfInterest((r[0] +r[2]) // 2, (r[1] + r[3]) // 2) for r in rects]
+
+
+def image_corner_points(im, settings):
+    grayscale = im.convert("L")
+
+    # naive attempt at preventing focal points from collecting at watermarks near the bottom
+    gd = ImageDraw.Draw(grayscale)
+    gd.rectangle([0, im.height*.9, im.width, im.height], fill="#999")
+
+    np_im = np.array(grayscale)
+
+    points = cv2.goodFeaturesToTrack(
+        np_im,
+        maxCorners=100,
+        qualityLevel=0.04,
+        minDistance=min(grayscale.width, grayscale.height)*0.07,
+        useHarrisDetector=False,
+    )
+
+    if points is None:
+        return []
+
+    focal_points = []
+    for point in points:
+        x, y = point.ravel()
+        focal_points.append(PointOfInterest(x, y))
+
+    return focal_points
+
+
+def image_entropy_points(im, settings):
+    landscape = im.height < im.width
+    portrait = im.height > im.width
+    if landscape:
+      move_idx = [0, 2]
+      move_max = im.size[0]
+    elif portrait:
+      move_idx = [1, 3]
+      move_max = im.size[1]
+    else:
+      return []
+
+    e_max = 0
+    crop_current = [0, 0, settings.crop_width, settings.crop_height]
+    crop_best = crop_current
+    while crop_current[move_idx[1]] < move_max:
+        crop = im.crop(tuple(crop_current))
+        e = image_entropy(crop)
+
+        if (e > e_max):
+          e_max = e
+          crop_best = list(crop_current)
+
+        crop_current[move_idx[0]] += 4
+        crop_current[move_idx[1]] += 4
+
+    x_mid = int(crop_best[0] + settings.crop_width/2)
+    y_mid = int(crop_best[1] + settings.crop_height/2)
+
+    return [PointOfInterest(x_mid, y_mid)]
+
+
+def image_entropy(im):
+    # greyscale image entropy
+    band = np.asarray(im.convert("1"))
+    hist, _ = np.histogram(band, bins=range(0, 256))
+    hist = hist[hist > 0]
+    return -np.log2(hist / hist.sum()).sum()
+
+
+def poi_average(pois, settings, im=None):
+    weight = 0.0
+    x = 0.0
+    y = 0.0
+    for pois in pois:
+        if settings.annotate_image and im is not None:
+          w = 4 * 0.5 * sqrt(pois.weight)
+          d = ImageDraw.Draw(im)
+          d.ellipse([
+            pois.x - w, pois.y - w,
+            pois.x + w, pois.y + w ], fill=BLUE)
+        weight += pois.weight
+        x += pois.x * pois.weight
+        y += pois.y * pois.weight
+    avg_x = round(x / weight)
+    avg_y = round(y / weight)
+
+    return PointOfInterest(avg_x, avg_y)
+
+
+class PointOfInterest:
+  def __init__(self, x, y, weight=1.0):
+    self.x = x
+    self.y = y
+    self.weight = weight
+
+
+class Settings:
+  def __init__(self, crop_width=512, crop_height=512, corner_points_weight=0.5, entropy_points_weight=0.5, face_points_weight=0.5, annotate_image=False):
+    self.crop_width = crop_width
+    self.crop_height = crop_height
+    self.corner_points_weight = corner_points_weight
+    self.entropy_points_weight = entropy_points_weight
+    self.face_points_weight = entropy_points_weight
+    self.annotate_image = annotate_image
+    self.destop_view_image = False
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