From 6fa426711bfb7c7d8027878ff5c30940e50e3d82 Mon Sep 17 00:00:00 2001
From: amuliang <982632988@qq.com>
Date: Mon, 18 Mar 2024 15:43:03 +0800
Subject: [PATCH] =?UTF-8?q?=E4=BF=AE=E5=A4=8DIDAT=E5=9D=97=E5=A4=A7?=
 =?UTF-8?q?=E5=B0=8F=E7=9A=84=E9=97=AE=E9=A2=98?=
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---
 type/PNG.py | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/type/PNG.py b/type/PNG.py
index dc1cddf..e2cc200 100644
--- a/type/PNG.py
+++ b/type/PNG.py
@@ -174,16 +174,22 @@ class PNG:
         changed = False
         b = False
         idat_append = []
+        idat_length = 65445
+        if len(idats) > 0: # 有时候IDAT块大小不是65445，默认用第一个IDAT块大小来检测之后的块
+            idat_length = idats[0][1]
         for idat in idats:
             if not b:
                 # 默认每个IDAT数据块最大为65445，如果出现一个数据块小于65445，说明数据块结束。如果后续又出现了IDAT数据块，则说明可能有异常数据
-                if idat[1] < 65445:
+                if idat[1] < idat_length:
                     b = True
             else:
                 print('[x] 检测到异常IDAT数据块')
                 idat_data = data[idat[0]: idat[0]+idat[1]]
-                idat_result = binascii.hexlify(zlib.decompress(idat_data)) # 究竟是不是要这样处理有待研究
-                idat_append.append[idat_result]
+                try:
+                    idat_result = binascii.hexlify(zlib.decompress(idat_data)) # 究竟是不是要这样处理有待研究
+                except Exception as e:
+                    idat_result = idat_data
+                idat_append.append(idat_result)
         
         return changed, data, idat_append
     
@@ -196,7 +202,9 @@ class PNG:
         pixels_b = []
         for y in range(height):
             for x in range(width):
-                r, g, b = image.getpixel((x, y))
+                # result = image.getpixel((x, y))
+                # print(result)
+                r, g, b, a = image.getpixel((x, y))
                 pixels_r.append(r)
                 pixels_g.append(g)
                 pixels_b.append(b)