Allow RGB and RGBA values for P image putpixel

Tests/test_image_access.py

@@ -175,6 +175,12 @@ def test_signedness(self):
             self.check(mode, 2**15+1)
             self.check(mode, 2**16-1)
 
+    def test_p_putpixel_rgb_rgba(self):
+        for color in [(255, 0, 0), (255, 0, 0, 255)]:
+            im = Image.new("P", (1, 1), 0)
+            im.putpixel((0, 0), color)
+            self.assertEqual(im.convert("RGB").getpixel((0, 0)), (255, 0, 0))
+
 
 @unittest.skipIf(cffi is None, "No cffi")
 class TestCffiPutPixel(TestImagePutPixel):
@@ -294,6 +300,13 @@ def test_reference_counting(self):
                 # pixels can contain garbage if image is released
                 self.assertEqual(px[i, 0], 0)
 
+    def test_p_putpixel_rgb_rgba(self):
+        for color in [(255, 0, 0), (255, 0, 0, 255)]:
+            im = Image.new("P", (1, 1), 0)
+            access = PyAccess.new(im, False)
+            access.putpixel((0, 0), color)
+            self.assertEqual(im.convert("RGB").getpixel((0, 0)), (255, 0, 0))
+
 
 class TestEmbeddable(unittest.TestCase):
     @unittest.skipIf(not sys.platform.startswith('win32') or

docs/reference/PixelAccess.rst

@@ -65,7 +65,8 @@ Access using negative indexes is also possible.
 
         Modifies the pixel at x,y. The color is given as a single
         numerical value for single band images, and a tuple for
-        multi-band images
+        multi-band images. In addition to this, RGB and RGBA tuples
+        are accepted for P images.
 
         :param xy: The pixel coordinate, given as (x, y).
         :param color: The pixel value according to its mode. e.g. tuple (r, g, b) for RGB mode)

src/PIL/Image.py

@@ -1651,7 +1651,8 @@ def putpixel(self, xy, value):
         """
         Modifies the pixel at the given position. The color is given as
         a single numerical value for single-band images, and a tuple for
-        multi-band images.
+        multi-band images. In addition to this, RGB and RGBA tuples are
+        accepted for P images.
 
         Note that this method is relatively slow.  For more extensive changes,
         use :py:meth:`~PIL.Image.Image.paste` or the :py:mod:`~PIL.ImageDraw`
@@ -1674,6 +1675,11 @@ def putpixel(self, xy, value):
 
         if self.pyaccess:
             return self.pyaccess.putpixel(xy, value)
+
+        if self.mode == "P" and \
+           isinstance(value, (list, tuple)) and len(value) in [3, 4]:
+            # RGB or RGBA value for a P image
+            value = self.palette.getcolor(value)
         return self.im.putpixel(xy, value)
 
     def remap_palette(self, dest_map, source_palette=None):

src/PIL/PyAccess.py

@@ -53,6 +53,8 @@ def __init__(self, img, readonly=False):
 
         # Keep pointer to im object to prevent dereferencing.
         self._im = img.im
+        if self._im.mode == "P":
+            self._palette = img.palette
 
         # Debugging is polluting test traces, only useful here
         # when hacking on PyAccess
@@ -80,6 +82,12 @@ def __setitem__(self, xy, color):
         if y < 0:
             y = self.ysize + y
         (x, y) = self.check_xy((x, y))
+
+        if self._im.mode == "P" and \
+           isinstance(color, (list, tuple)) and len(color) in [3, 4]:
+            # RGB or RGBA value for a P image
+            color = self._palette.getcolor(color)
+
         return self.set_pixel(x, y, color)
 
     def __getitem__(self, xy):