imageloader.py simplification: multiprocessing

fftcg/imageloader.py

@@ -1,7 +1,6 @@
 import io
 import logging
-import queue
-import threading
+import multiprocessing
 
 import requests
 from PIL import Image
@@ -9,20 +8,11 @@ from PIL import Image
 from fftcg.utils import RESOLUTION
 
 
-class ImageLoader(threading.Thread):
-    def __init__(self, url_queue: queue.Queue):
-        super().__init__()
-
-        self.__queue = url_queue
-        self.__images = {}
-
-    def run(self) -> None:
+class ImageLoader:
+    @classmethod
+    def _load(cls, url: str) -> Image.Image:
         logger = logging.getLogger(__name__)
 
-        while not self.__queue.empty():
-            # take next url
-            url = self.__queue.get()
-
         # fetch image (retry on fail)
         while True:
             logger.info(f"downloading image {url}")
@@ -31,45 +21,13 @@ class ImageLoader(threading.Thread):
                 image = Image.open(io.BytesIO(res.content))
 
                 # unify images
-                    image.convert("RGB")
-                    image = image.resize(RESOLUTION, Image.BICUBIC)
-                    break
+                image.convert(mode="RGB")
+                return image.resize(RESOLUTION, Image.BICUBIC)
+
             except requests.exceptions.RequestException:
                 pass
 
-            # put image in correct position
-            self.__images[url] = image
-
-            # image is processed
-            self.__queue.task_done()
-
     @classmethod
     def load(cls, urls: list[str], num_threads: int) -> list[Image.Image]:
-        url_queue = queue.Queue()
-        for url in urls:
-            url_queue.put(url)
-
-        loaders = []
-        for _ in range(num_threads):
-            loader = cls(url_queue)
-            loaders.append(loader)
-            loader.start()
-
-        url_queue.join()
-
-        # stitch all "images" dicts together
-        images = {}
-        for loader in loaders:
-            images |= loader.images
-
-        # sort images to match the initial "urls" list
-        images = [
-            images[url]
-            for url in urls
-        ]
-
-        return images
-
-    @property
-    def images(self) -> dict[str, Image.Image]:
-        return self.__images
+        with multiprocessing.Pool(num_threads) as p:
+            return p.map(ImageLoader._load, urls)

main.py

@@ -31,7 +31,7 @@ def main() -> None:
     args = parser.parse_args()
 
     # set up logging
-    logging.basicConfig(level=logging.INFO, format="%(levelname)s: %(threadName)s %(message)s")
+    logging.basicConfig(level=logging.INFO, format="%(levelname)s: %(processName)s %(message)s")
 
     # output directory
     if not os.path.exists("out"):