private MultipleFrames readImageFolder (int minFrame, int maxFrame) throws IOException{

       MultipleFrames mF = new MultipleFrames();

       for (int i=0; i<(int) Math.abs (maxFrame-minFrame+1); i++) {

            byte [] singleFrame = null;
            try {

                singleFrame = this.readSingleFrame(minFrame+i);

            } finally {

                if (singleFrame != null) {
                    mF.frames.add (singleFrame);
                }
            }

       }
       return mF;