refactoring for coverage

pypdf/filters.py

@@ -668,39 +668,22 @@ def _get_imagemode(
  color_space = color_space[1]
  if isinstance(color_space, IndirectObject):
  color_space = color_space.get_object()
- if isinstance(color_space, list):
- typ = color_space[0]
- if isinstance(color_space[0], IndirectObject):
- typ = typ.get_object()
- if typ == "/DeviceN":
- """
- x = color_space[1]
- if isinstance(x,IndirectObject):
- x = x.get_object()
- color_components = x
- """
- color_space = color_space[2]
- if isinstance(color_space, IndirectObject):
- color_space = color_space.get_object()
- else:
- color_space = color_space[1].get_object().get("/Alternate", "")
- elif not isinstance(color_space, str):
- color_space = color_space[1].get_object().get("/Alternate", "")
- color_components = 1 if "Gray" in color_space else 2
- if not (isinstance(color_space, str) and "Gray" in color_space):
- color_space = "palette"
+ mode = _get_imagemode(color_space, color_components, prev_mode)
+ if mode in ("RGB", "CMYK"):
+ mode = "P"
+ return mode
  elif color_space[0] == "/Separation":
  color_space = color_space[2]
  elif color_space[0] == "/DeviceN":
  color_components = len(color_space[1])
  color_space = color_space[2]
- if isinstance(color_space, IndirectObject):
+ if isinstance(color_space, IndirectObject): # pragma: no cover
  color_space = color_space.get_object()
 
  mode_map = {
- "1bit": "1", # 0 will be used for 1 bit
+ "1bit": "1", # pos [0] will be used for 1 bit
  "/DeviceGray": "L", # must be in pos [1]
- "palette": "P", # reserved for color_components alignment
+ "palette": "P", # must be in pos [2] for color_components align.
  "/DeviceRGB": "RGB", # must be in pos [3]
  "/DeviceCMYK": "CMYK", # must be in pos [4]
  "2bit": "2bits", # 2 bits images