initial attempt at plugin

src/PIL/HeifImagePlugin.py

@@ -0,0 +1,38 @@
+import io
+
+from . import Image, ImageFile
+
+try:
+    import pyheif
+    print("!")
+except ImportError:
+    pyheif = None
+
+def _accept(prefix):
+    check = pyheif.check(prefix)
+    return check != pyheif.heif_filetype_no
+
+
+class HeifImageFile(ImageFile.ImageFile):
+    format = "HEIF"
+    format_description = "HEIF Image File Format"
+
+    def _open(self):
+        b = self.fp.read()
+        if not _accept(b):
+            raise ValueError("Not a HEIF image file")
+
+        heif_file = pyheif.read(b)
+        self._size = heif_file.size
+        self.mode = heif_file.mode
+        self.fp = io.BytesIO(heif_file.data)
+        self.tile = [("raw", (0, 0) + heif_file.size, 0, (heif_file.mode, heif_file.stride))]
+
+
+if pyheif:
+    print("!!")
+    Image.register_open(HeifImageFile.format, HeifImageFile, _accept)
+    Image.register_extensions(HeifImageFile.format, [".heif", ".heic", ".hif"])
+    Image.register_mime(HeifImageFile.format, "image/heif")
+    Image.register_mime(HeifImageFile.format, "image/heic")
+

src/PIL/__init__.py

@@ -98,6 +98,7 @@ _plugins = [
     "GifImagePlugin",
     "GribStubImagePlugin",
     "Hdf5StubImagePlugin",
+    "HeifImagePlugin",
     "IcnsImagePlugin",
     "IcoImagePlugin",
     "ImImagePlugin",

venv/pyvenv.cfg

@@ -0,0 +1,3 @@
+home = /usr/local/Cellar/python@3.8/3.8.3_2/bin
+include-system-site-packages = false
+version = 3.8.3