Image Distributor & Thumbnail Generator

generate_thumbnails.py

#!/usr/bin/env python3
"""
Image Distributor & Thumbnail Generator
----------------------------------------
1. Creates 10 subfolders inside a target directory
2. Randomly distributes ~1000 images across them (~100 each)
3. For each image, generates 10 WordPress thumbnail sizes

Usage:
    python generate_thumbnails.py /path/to/your/images

Requirements:
    pip install Pillow
"""

import os
import sys
import random
import shutil
from pathlib import Path
from PIL import Image

# ── Configuration ─────────────────────────────────────────────────────────────

NUM_FOLDERS = 10

# 10 WordPress / web thumbnail sizes — all within 1024px max dimension
THUMBNAIL_SIZES = [
    (100, 100),   # WooCommerce tiny
    (150, 150),   # WP default thumbnail (square)
    (250, 250),   # Sidebar / widget square
    (300, 300),   # WP medium square
    (320, 240),   # Mobile small landscape
    (400, 300),   # Card / widget landscape
    (600, 400),   # Blog featured image
    (768, 432),   # Tablet 16:9
    (800, 600),   # Medium-large landscape
    (1024, 576),  # Full-width 16:9
]

# Supported input image extensions
IMAGE_EXTENSIONS = {".jpg", ".jpeg", ".png", ".webp", ".bmp", ".tiff", ".gif"}

# ── Helpers ───────────────────────────────────────────────────────────────────

def collect_images(source_dir: Path) -> list[Path]:
    """Return a shuffled list of image files in source_dir (non-recursive)."""
    images = [
        f for f in source_dir.iterdir()
        if f.is_file() and f.suffix.lower() in IMAGE_EXTENSIONS
    ]
    random.shuffle(images)
    return images


def create_folders(base_dir: Path) -> list[Path]:
    """Create 10 numbered subfolders and return their paths."""
    folders = []
    for i in range(1, NUM_FOLDERS + 1):
        folder = base_dir / f"batch_{i:02d}"
        folder.mkdir(exist_ok=True)
        folders.append(folder)
    return folders


def distribute_images(images: list[Path], folders: list[Path]) -> dict[Path, list[Path]]:
    """
    Move images into folders as evenly as possible.
    Returns a dict mapping each folder to its list of moved images.
    """
    mapping: dict[Path, list[Path]] = {f: [] for f in folders}

    for idx, img_path in enumerate(images):
        target_folder = folders[idx % NUM_FOLDERS]
        dest = target_folder / img_path.name
        # Handle filename collisions
        if dest.exists():
            stem = img_path.stem
            suffix = img_path.suffix
            dest = target_folder / f"{stem}_{idx}{suffix}"
        shutil.move(str(img_path), dest)
        mapping[target_folder].append(dest)

    return mapping


def make_thumbnail(src: Path, folder: Path, width: int, height: int) -> None:
    """
    Create a thumbnail of (width x height) from src image.
    Uses LANCZOS resampling. Fits the image within the box without cropping.
    Saves as JPEG regardless of source format.
    """
    thumb_name = f"{src.stem}-thumb-{width}x{height}.jpg"
    thumb_path = folder / thumb_name

    with Image.open(src) as img:
        # Convert palette / RGBA images so they save cleanly as JPEG
        if img.mode in ("P", "RGBA", "LA"):
            img = img.convert("RGB")
        elif img.mode != "RGB":
            img = img.convert("RGB")

        img_copy = img.copy()
        img_copy.thumbnail((width, height), Image.LANCZOS)
        img_copy.save(thumb_path, "JPEG", quality=85, optimize=True)


def generate_thumbnails(mapping: dict[Path, list[Path]]) -> None:
    """Generate all thumbnail sizes for every image in every folder."""
    total_thumbs = 0
    for folder, images in mapping.items():
        print(f"\n  📁 {folder.name}  ({len(images)} images)")
        for img_path in images:
            for width, height in THUMBNAIL_SIZES:
                try:
                    make_thumbnail(img_path, folder, width, height)
                    total_thumbs += 1
                except Exception as e:
                    print(f"    ⚠️  Skipped thumbnail {width}x{height} for {img_path.name}: {e}")
        thumb_count = len(images) * len(THUMBNAIL_SIZES)
        print(f"     ✅ {thumb_count} thumbnails generated")
    print(f"\n  🎉 Total thumbnails created: {total_thumbs}")


# ── Main ──────────────────────────────────────────────────────────────────────

def main():
    if len(sys.argv) < 2:
        print("Usage: python generate_thumbnails.py /path/to/your/images")
        sys.exit(1)

    source_dir = Path(sys.argv[1]).resolve()
    if not source_dir.is_dir():
        print(f"Error: '{source_dir}' is not a valid directory.")
        sys.exit(1)

    print(f"\n🔍 Scanning: {source_dir}")
    images = collect_images(source_dir)
    print(f"   Found {len(images)} image(s)")

    if not images:
        print("No supported images found. Supported formats: JPG, PNG, WEBP, BMP, TIFF, GIF")
        sys.exit(0)

    print(f"\n📂 Creating {NUM_FOLDERS} folders...")
    folders = create_folders(source_dir)

    print(f"\n🔀 Distributing images across folders...")
    mapping = distribute_images(images, folders)

    for folder, imgs in mapping.items():
        print(f"   {folder.name}: {len(imgs)} images")

    print(f"\n🖼️  Generating thumbnails ({len(THUMBNAIL_SIZES)} sizes per image)...")
    print(f"   Sizes: {', '.join(f'{w}x{h}' for w, h in THUMBNAIL_SIZES)}")
    generate_thumbnails(mapping)

    print("\n✅ All done!")
    print(f"   📁 {NUM_FOLDERS} folders")
    print(f"   🖼️  {len(images)} original images distributed")
    print(f"   🔖 Up to {len(images) * len(THUMBNAIL_SIZES)} thumbnails generated")


if __name__ == "__main__":
    main()