Fixed incorrect patch.

9 years ago · d5e60e8506
1 changed files with 2 additions and 2 deletions
--- a/src/ImageSharp/Formats/Png/Zlib/Adler32.cs
+++ b/src/ImageSharp/Formats/Png/Zlib/Adler32.cs
@ -138,7 +138,7 @@ namespace ImageSharp.Formats
            }

            // (By Per Bothner)
-            uint s1 = this.checksum;
+            uint s1 = this.checksum & 0xFFFF;
            uint s2 = this.checksum >> 16;

            while (count > 0)
@ -151,7 +151,7 @@ namespace ImageSharp.Formats
                count -= n;
                while (--n > -1)
                {
-                    s1 = s1 + buffer[offset++];
+                    s1 = s1 + (uint)(buffer[offset++] & 0xff);
                    s2 = s2 + s1;
                }