From e65e5bea45e92a118590c69c022d6e6741e3b101 Mon Sep 17 00:00:00 2001
From: Andrew Murray <radarhere@users.noreply.github.com>
Date: Tue, 10 Jun 2025 20:30:18 +1000
Subject: [PATCH] Start decoding with a zero-initialized array of previously
 seen pixels

---
 Tests/images/op_index.qoi | Bin 0 -> 15 bytes
 Tests/test_file_qoi.py    |   6 ++++++
 src/PIL/QoiImagePlugin.py |   2 +-
 3 files changed, 7 insertions(+), 1 deletion(-)
 create mode 100644 Tests/images/op_index.qoi

diff --git a/Tests/images/op_index.qoi b/Tests/images/op_index.qoi
new file mode 100644
index 0000000000000000000000000000000000000000..e626aafe6a433487cbacb4bdbcbbe5e66e8d07db
GIT binary patch
literal 15
TcmXTS&rD-rU|<Ac76wxQ7b*ek

literal 0
HcmV?d00001

diff --git a/Tests/test_file_qoi.py b/Tests/test_file_qoi.py
index fd4b981ce..7ce1da209 100644
--- a/Tests/test_file_qoi.py
+++ b/Tests/test_file_qoi.py
@@ -28,3 +28,9 @@ def test_invalid_file() -> None:
 
     with pytest.raises(SyntaxError):
         QoiImagePlugin.QoiImageFile(invalid_file)
+
+
+def test_op_index() -> None:
+    # QOI_OP_INDEX as the first chunk
+    with Image.open("Tests/images/op_index.qoi") as im:
+        assert im.getpixel((0, 0)) == (0, 0, 0, 0)
diff --git a/src/PIL/QoiImagePlugin.py b/src/PIL/QoiImagePlugin.py
index df552243e..75070abd7 100644
--- a/src/PIL/QoiImagePlugin.py
+++ b/src/PIL/QoiImagePlugin.py
@@ -51,7 +51,7 @@ class QoiDecoder(ImageFile.PyDecoder):
         assert self.fd is not None
 
         self._previously_seen_pixels = {}
-        self._add_to_previous_pixels(bytearray((0, 0, 0, 255)))
+        self._previous_pixel = bytearray((0, 0, 0, 255))
 
         data = bytearray()
         bands = Image.getmodebands(self.mode)