BUG: Handle chained colorspace for inline images when no filter is set

Closes #2998.

pypdf/generic/_data_structures.py

@@ -1343,6 +1343,8 @@ def _read_inline_image(self, stream: StreamType) -> Dict[str, Any]:
             data = extract_inline_DCT(stream)
         elif filtr == "not set":
             cs = settings.get("/CS", "")
+            if isinstance(cs, list):
+                cs = cs[0]
             if "RGB" in cs:
                 lcs = 3
             elif "CMYK" in cs:

tests/test_images.py

@@ -473,3 +473,14 @@ def test_4bits_images(caplog):
     name = "iss2411.png"
     img = Image.open(BytesIO(get_data_from_url(url, name=name)))
     assert image_similarity(reader.pages[0].images[1].image, img) == 1.0
+
+
+@pytest.mark.enable_socket
+def test_no_filter_with_colorspace_as_list():
+    """Tests for #2998"""
+    url = "https://github.com/user-attachments/files/18058571/9bf7a2e2-72c8-4ac1-b8ae-164df16c8cef.pdf"
+    name = "iss2998.pdf"
+    reader = PdfReader(BytesIO(get_data_from_url(url, name=name)))
+
+    page = reader.pages[0]
+    page.images.items()