From 6663ed929b41c3c89ec1469b78fbf6c36af487cc Mon Sep 17 00:00:00 2001 From: Andrew Murray Date: Sat, 17 Sep 2022 17:56:36 +1000 Subject: [PATCH] If first frame has transparency for RGB_ALWAYS, use RGBA --- Tests/test_file_gif.py | 17 ++++++++++++----- src/PIL/GifImagePlugin.py | 24 +++++++++++++++--------- 2 files changed, 27 insertions(+), 14 deletions(-) diff --git a/Tests/test_file_gif.py b/Tests/test_file_gif.py index 68cb8a36e8d..0f7f3814b4b 100644 --- a/Tests/test_file_gif.py +++ b/Tests/test_file_gif.py @@ -84,17 +84,24 @@ def test_l_mode_transparency(): def test_strategy(): + with Image.open("Tests/images/iss634.gif") as im: + expected_rgb_always = im.convert("RGB") + with Image.open("Tests/images/chi.gif") as im: - expected_zero = im.convert("RGB") + expected_rgb_always_rgba = im.convert("RGBA") im.seek(1) - expected_one = im.convert("RGB") + expected_different = im.convert("RGB") try: GifImagePlugin.LOADING_STRATEGY = GifImagePlugin.LoadingStrategy.RGB_ALWAYS - with Image.open("Tests/images/chi.gif") as im: + with Image.open("Tests/images/iss634.gif") as im: assert im.mode == "RGB" - assert_image_equal(im, expected_zero) + assert_image_equal(im, expected_rgb_always) + + with Image.open("Tests/images/chi.gif") as im: + assert im.mode == "RGBA" + assert_image_equal(im, expected_rgb_always_rgba) GifImagePlugin.LOADING_STRATEGY = ( GifImagePlugin.LoadingStrategy.RGB_AFTER_DIFFERENT_PALETTE_ONLY @@ -105,7 +112,7 @@ def test_strategy(): im.seek(1) assert im.mode == "P" - assert_image_equal(im.convert("RGB"), expected_one) + assert_image_equal(im.convert("RGB"), expected_different) # Change to RGB mode when a frame has an individual palette with Image.open("Tests/images/iss634.gif") as im: diff --git a/src/PIL/GifImagePlugin.py b/src/PIL/GifImagePlugin.py index 2e11df54c0a..ab165dd518b 100644 --- a/src/PIL/GifImagePlugin.py +++ b/src/PIL/GifImagePlugin.py @@ -299,11 +299,13 @@ def _seek(self, frame, update_image=True): self.im.paste(self.dispose, self.dispose_extent) self._frame_palette = palette or self.global_palette + self._frame_transparency = frame_transparency if frame == 0: if self._frame_palette: - self.mode = ( - "RGB" if LOADING_STRATEGY == LoadingStrategy.RGB_ALWAYS else "P" - ) + if LOADING_STRATEGY == LoadingStrategy.RGB_ALWAYS: + self.mode = "RGBA" if frame_transparency is not None else "RGB" + else: + self.mode = "P" else: self.mode = "L" @@ -313,7 +315,6 @@ def _seek(self, frame, update_image=True): palette = copy(self.global_palette) self.palette = palette else: - self._frame_transparency = frame_transparency if self.mode == "P": if ( LOADING_STRATEGY != LoadingStrategy.RGB_AFTER_DIFFERENT_PALETTE_ONLY @@ -386,7 +387,8 @@ def _rgb(color): transparency = -1 if frame_transparency is not None: if frame == 0: - self.info["transparency"] = frame_transparency + if LOADING_STRATEGY != LoadingStrategy.RGB_ALWAYS: + self.info["transparency"] = frame_transparency elif self.mode not in ("RGB", "RGBA"): transparency = frame_transparency self.tile = [ @@ -410,9 +412,9 @@ def load_prepare(self): temp_mode = "P" if self._frame_palette else "L" self._prev_im = None if self.__frame == 0: - if "transparency" in self.info: + if self._frame_transparency is not None: self.im = Image.core.fill( - temp_mode, self.size, self.info["transparency"] + temp_mode, self.size, self._frame_transparency ) elif self.mode in ("RGB", "RGBA"): self._prev_im = self.im @@ -429,8 +431,12 @@ def load_prepare(self): def load_end(self): if self.__frame == 0: if self.mode == "P" and LOADING_STRATEGY == LoadingStrategy.RGB_ALWAYS: - self.mode = "RGB" - self.im = self.im.convert("RGB", Image.Dither.FLOYDSTEINBERG) + if self._frame_transparency is not None: + self.im.putpalettealpha(self._frame_transparency, 0) + self.mode = "RGBA" + else: + self.mode = "RGB" + self.im = self.im.convert(self.mode, Image.Dither.FLOYDSTEINBERG) return if self.mode == "P" and self._prev_im: if self._frame_transparency is not None: