access BGR;15/16 pixels as BGR, not RGB

Author: Yay295

Tests/test_lib_pack.py

@@ -362,9 +362,9 @@ def test_RGB(self) -> None:
         )
 
     def test_BGR(self) -> None:
-        self.assert_unpack("BGR;15", "BGR;15", 3, (8, 131, 0), (24, 0, 8), (41, 131, 8))
+        self.assert_unpack("BGR;15", "BGR;15", 2, (0, 131, 8), (8, 0, 24), (8, 131, 41))
         self.assert_unpack(
-            "BGR;16", "BGR;16", 3, (8, 64, 0), (24, 129, 0), (41, 194, 0)
+            "BGR;16", "BGR;16", 2, (0, 64, 8), (0, 129, 24), (0, 194, 41)
         )
         self.assert_unpack("BGR;24", "BGR;24", 3, (1, 2, 3), (4, 5, 6), (7, 8, 9))
 

src/libImaging/Access.c

@@ -86,19 +86,19 @@ get_pixel_BGR15(Imaging im, int x, int y, void *color) {
     UINT8 *in = (UINT8 *)&im->image8[y][x * 2];
     UINT16 pixel = in[0] + (in[1] << 8);
     char *out = color;
-    out[0] = (pixel & 31) * 255 / 31;
+    out[0] = ((pixel >> 10) & 31) * 255 / 31;
     out[1] = ((pixel >> 5) & 31) * 255 / 31;
-    out[2] = ((pixel >> 10) & 31) * 255 / 31;
+    out[2] = (pixel & 31) * 255 / 31;
 }
 
 static void
 get_pixel_BGR16(Imaging im, int x, int y, void *color) {
     UINT8 *in = (UINT8 *)&im->image8[y][x * 2];
     UINT16 pixel = in[0] + (in[1] << 8);
     char *out = color;
-    out[0] = (pixel & 31) * 255 / 31;
+    out[0] = ((pixel >> 11) & 31) * 255 / 31;
     out[1] = ((pixel >> 5) & 63) * 255 / 63;
-    out[2] = ((pixel >> 11) & 31) * 255 / 31;
+    out[2] = (pixel & 31) * 255 / 31;
 }
 
 static void