diff --git a/pypdf/filters.py b/pypdf/filters.py
index 5e6a10f782..137e3603a3 100644
--- a/pypdf/filters.py
+++ b/pypdf/filters.py
@@ -190,16 +190,19 @@ def _decode_png_prediction(data: bytes, columns: int, rowlength: int) -> bytes:
             filter_byte = rowdata[0]
 
             if filter_byte == 0:
+                # PNG None Predictor
                 pass
             elif filter_byte == 1:
+                # PNG Sub Predictor
                 for i in range(bpp + 1, rowlength):
                     rowdata[i] = (rowdata[i] + rowdata[i - bpp]) % 256
             elif filter_byte == 2:
+                # PNG Up Predictor
                 for i in range(1, rowlength):
                     rowdata[i] = (rowdata[i] + prev_rowdata[i]) % 256
             elif filter_byte == 3:
+                # PNG Average Predictor
                 for i in range(1, bpp + 1):
-                    # left = 0
                     floor = prev_rowdata[i] // 2
                     rowdata[i] = (rowdata[i] + floor) % 256
                 for i in range(bpp + 1, rowlength):
@@ -207,12 +210,9 @@ def _decode_png_prediction(data: bytes, columns: int, rowlength: int) -> bytes:
                     floor = (left + prev_rowdata[i]) // 2
                     rowdata[i] = (rowdata[i] + floor) % 256
             elif filter_byte == 4:
+                # PNG Paeth Predictor
                 for i in range(1, bpp + 1):
-                    # left = 0
-                    up = prev_rowdata[i]
-                    # up_left = 0
-                    paeth = up
-                    rowdata[i] = (rowdata[i] + paeth) % 256
+                    rowdata[i] = (rowdata[i] + prev_rowdata[i]) % 256
                 for i in range(bpp + 1, rowlength):
                     left = rowdata[i - bpp]
                     up = prev_rowdata[i]