Upload imgproc.py

imgproc.py

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+import random
+
+from PIL import Image
+import numpy as np
+
+
+def center_crop_arr(pil_image, image_size):
+    """
+    Center cropping implementation from ADM.
+    https://github.com/openai/guided-diffusion/blob/8fb3ad9197f16bbc40620447b2742e13458d2831/guided_diffusion/image_datasets.py#L126
+    """
+    while min(*pil_image.size) >= 2 * image_size:
+        pil_image = pil_image.resize(tuple(x // 2 for x in pil_image.size), resample=Image.BOX)
+
+    scale = image_size / min(*pil_image.size)
+    pil_image = pil_image.resize(tuple(round(x * scale) for x in pil_image.size), resample=Image.BICUBIC)
+
+    arr = np.array(pil_image)
+    crop_y = (arr.shape[0] - image_size) // 2
+    crop_x = (arr.shape[1] - image_size) // 2
+    return Image.fromarray(arr[crop_y : crop_y + image_size, crop_x : crop_x + image_size])
+
+
+def center_crop(pil_image, crop_size):
+    while pil_image.size[0] >= 2 * crop_size[0] and pil_image.size[1] >= 2 * crop_size[1]:
+        pil_image = pil_image.resize(tuple(x // 2 for x in pil_image.size), resample=Image.BOX)
+
+    scale = max(crop_size[0] / pil_image.size[0], crop_size[1] / pil_image.size[1])
+    pil_image = pil_image.resize(tuple(round(x * scale) for x in pil_image.size), resample=Image.BICUBIC)
+
+    # crop_left = random.randint(0, pil_image.size[0] - crop_size[0])
+    # crop_upper = random.randint(0, pil_image.size[1] - crop_size[1])
+    crop_left = (pil_image.size[0] - crop_size[0]) // 2
+    crop_upper = (pil_image.size[1] - crop_size[1]) // 2
+    crop_right = crop_left + crop_size[0]
+    crop_lower = crop_upper + crop_size[1]
+    return pil_image.crop(box=(crop_left, crop_upper, crop_right, crop_lower))
+
+def var_center_crop(pil_image, crop_size_list, random_top_k=4):
+    w, h = pil_image.size
+    rem_percent = [min(cw / w, ch / h) / max(cw / w, ch / h) for cw, ch in crop_size_list]
+    crop_size = random.choice(
+        sorted(((x, y) for x, y in zip(rem_percent, crop_size_list)), reverse=True)[:random_top_k]
+    )[1]
+    return center_crop(pil_image, crop_size)
+
+def var_center_crop_128(pil_image, crop_size_list, random_top_k=4):
+    w, h = pil_image.size
+    rem_percent = [min(cw / w, ch / h) / max(cw / w, ch / h) for cw, ch in crop_size_list]
+    crop_size = random.choice(
+        sorted(((x, y) for x, y in zip(rem_percent, crop_size_list)), reverse=True)[:random_top_k]
+    )[1]
+    breakpoint()
+    return center_crop(pil_image, (((w//128)*128), ((h//128)*128)))
+
+
+def generate_crop_size_list(num_patches, patch_size, max_ratio=4.0):
+    assert max_ratio >= 1.0
+    crop_size_list = []
+    wp, hp = num_patches, 1
+    while wp > 0:
+        if max(wp, hp) / min(wp, hp) <= max_ratio:
+            if ((wp * patch_size)//32) % 2 == 0 and  ((hp * patch_size)//32) % 2 == 0:
+                crop_size_list.append((wp * patch_size, hp * patch_size))
+        if (hp + 1) * wp <= num_patches:
+            hp += 1
+        else:
+            wp -= 1
+    return crop_size_list
+
+
+def to_rgb_if_rgba(img: Image.Image):
+    if img.mode.upper() == "RGBA":
+        rgb_img = Image.new("RGB", img.size, (255, 255, 255))
+        rgb_img.paste(img, mask=img.split()[3])  # 3 is the alpha channel
+        return rgb_img
+    elif img.mode.upper() == "P":
+        return img.convert('RGB')
+    else:
+        return img