From 25e467a756d42d875de7f6a019ce36d8aa836c8a Mon Sep 17 00:00:00 2001
From: Andrew Murray <radarhere@users.noreply.github.com>
Date: Sat, 12 Aug 2017 12:11:36 +1000
Subject: [PATCH] Use frame count from FLI header

---
 PIL/FliImagePlugin.py | 38 +++++++++-----------------------------
 1 file changed, 9 insertions(+), 29 deletions(-)

diff --git a/PIL/FliImagePlugin.py b/PIL/FliImagePlugin.py
index a2d0e0fab..94b82540a 100644
--- a/PIL/FliImagePlugin.py
+++ b/PIL/FliImagePlugin.py
@@ -38,7 +38,7 @@ class FliImageFile(ImageFile.ImageFile):
     format = "FLI"
     format_description = "Autodesk FLI/FLC Animation"
     _close_exclusive_fp_after_loading = False
-    
+
     def _open(self):
 
         # HEAD
@@ -49,6 +49,9 @@ class FliImageFile(ImageFile.ImageFile):
                 s[20:22] == b"\x00\x00"):  # reserved
             raise SyntaxError("not an FLI/FLC file")
 
+        # frames
+        self.__framecount = i16(s[6:8])
+
         # image characteristics
         self.mode = "P"
         self.size = i16(s[8:10]), i16(s[10:12])
@@ -86,8 +89,6 @@ class FliImageFile(ImageFile.ImageFile):
         self.__frame = -1
         self.__fp = self.fp
         self.__rewind = self.fp.tell()
-        self._n_frames = None
-        self._is_animated = None
         self.seek(0)
 
     def _palette(self, palette, shift):
@@ -110,43 +111,22 @@ class FliImageFile(ImageFile.ImageFile):
 
     @property
     def n_frames(self):
-        if self._n_frames is None:
-            current = self.tell()
-            try:
-                while True:
-                    self.seek(self.tell() + 1)
-            except EOFError:
-                self._n_frames = self.tell() + 1
-            self.seek(current)
-        return self._n_frames
+        return self.__framecount
 
     @property
     def is_animated(self):
-        if self._is_animated is None:
-            current = self.tell()
-
-            try:
-                self.seek(1)
-                self._is_animated = True
-            except EOFError:
-                self._is_animated = False
-
-            self.seek(current)
-        return self._is_animated
+        return self.__framecount > 1
 
     def seek(self, frame):
         if frame == self.__frame:
             return
         if frame < self.__frame:
             self._seek(0)
+        if frame >= self.__framecount:
+            raise EOFError("no more images in FLI file")
 
-        last_frame = self.__frame
         for f in range(self.__frame + 1, frame + 1):
-            try:
-                self._seek(f)
-            except EOFError:
-                self.seek(last_frame)
-                raise EOFError("no more images in FLI file")
+            self._seek(f)
 
     def _seek(self, frame):
         if frame == 0: