src/utils/align_images.py

import os

from src.utils.face_alignment import image_align
from src.landmark_detector import LandmarksDetector


def align_images(img_files, aligned_dir, output_size=1024, x_scale=1, y_scale=1, em_scale=0.1, use_alpha=False):
    """
    Extracts and aligns all faces from images using DLib and a function from original FFHQ dataset preparation step
    python align_images.py /raw_images /aligned_images
    """

    ALIGNED_IMAGES_DIR = aligned_dir

    # Create the directory if it doesn't exist
    if not os.path.exists(ALIGNED_IMAGES_DIR):
        os.makedirs(ALIGNED_IMAGES_DIR)
    else:   # Remove existing files in the directory
        for file in os.listdir(ALIGNED_IMAGES_DIR):
            os.remove(os.path.join(ALIGNED_IMAGES_DIR, file))

    landmarks_detector = LandmarksDetector()
    for idx, img_path in enumerate(img_files, start=1):
        img_name = os.path.basename(img_path)
        print('Aligning %s ...' % img_name)
        try:
            raw_img_path = img_path
            fn = face_img_name = f'{idx:04d}_{os.path.splitext(img_name)[0]}_01.png'
            if os.path.isfile(os.path.join(ALIGNED_IMAGES_DIR, fn)):
                continue
            print('Getting landmarks...')
            for i, face_landmarks in enumerate(landmarks_detector.get_landmarks(raw_img_path), start=1):
                try:
                    print('Starting face alignment...')
                    face_img_name = f'{idx:04d}_{os.path.splitext(img_name)[0]}_{i:02d}.png'
                    aligned_face_path = os.path.join(ALIGNED_IMAGES_DIR, face_img_name)
                    image_align(raw_img_path, aligned_face_path, face_landmarks, output_size=output_size, x_scale=x_scale, y_scale=y_scale, em_scale=em_scale, alpha=use_alpha)
                    print('Wrote result %s\n' % aligned_face_path)
                except Exception as e:
                    print(f"Exception in face alignment for {img_name}: {e}")
        except Exception as e:
            print(f"Exception in landmark detection for {img_name}: {e}")
        
    # return absolute paths of aligned images
    return [os.path.join(ALIGNED_IMAGES_DIR, img) for img in os.listdir(ALIGNED_IMAGES_DIR)]