diff --git a/src/core.py b/src/core.py
--- a/src/core.py
+++ b/src/core.py
@@ -2,7 +2,9 @@ import os
 import multiprocessing
 import threading
 import logging
+
 import PIL
+
 from util import MsgQueue
 from gui import gui
 from analyzer import ImageAnalyzer
@@ -10,6 +12,7 @@ from analyzer.framecache import FrameCac
 from go.core import Go, isLegalPosition
 from statebag import StateBag
 import config as cfg
+import util
 
 log=logging.getLogger(__name__)
 
@@ -25,7 +28,7 @@ class Core:
 		self._ownMessages=MsgQueue(self._handleEvent)
 		self._guiMessages=MsgQueue()
 
-		self._imgs=sorted(os.listdir(cfg.misc.imgDir))
+		self._imgs=sorted(filter(lambda s: s.endswith(".jpg"), os.listdir(cfg.misc.imgDir)))
 		self._imgIndex=cfg.misc.defaultImage
 		imgPath=os.path.join(cfg.misc.imgDir,self._imgs[self._imgIndex])
 		self._frame=PIL.Image.open(imgPath)
@@ -45,9 +48,10 @@ class Core:
 
 	def relativeFrame(self,step):
 		self._imgIndex=(self._imgIndex+step)%len(self._imgs)
-		imgPath=os.path.join(cfg.misc.imgDir,self._imgs[self._imgIndex])
+		filename=self._imgs[self._imgIndex]
+		imgPath=os.path.join(cfg.misc.imgDir,filename)
 		self._frame=PIL.Image.open(imgPath)
-		self._guiMessages.send("setCurrentFrame",(self._frame.copy(),gui.PREVIEW))
+		self._guiMessages.send("setCurrentFrame",(self._frame.copy(),gui.PREVIEW,filename))
 		self.preview()
 
 	def sendParams(self):