Function convert_folder_to_grayscale

utils/poster_eval_utils.py:413–421

(input_folder, output_folder)

    return avg_l2, avg_cos_sim

def convert_folder_to_grayscale(input_folder, output_folder):
    os.makedirs(output_folder, exist_ok=True)
    for filename in os.listdir(input_folder):
        if filename.lower().endswith(('.jpg', '.jpeg', '.png')):
            input_path = os.path.join(input_folder, filename)
            output_path = os.path.join(output_folder, filename)

            img = Image.open(input_path).convert('L').convert('RGB')  # grayscale + 3 channels
            img.save(output_path)

def compute_fid_with_grayscale(reference_poster_folder, generated_poster_img_folder, clip=False):
    # Step 1: Create grayscale versions in tmp/