public void stripFunction(){
		//set validness of filename to false as initialization and other general initialization
		boolean valid=false; //if inputs are valid
		String inFileName=_curDir; //input filename
		String outFileName=_saveDir; //output file name
		int overrideChoice=-1; //for override button choice
		String path=""; //variable for path

		//get output file
		if(FileChecker.validInFile(inFileName,Constants.VIDEO_AUDIO_TYPE)){
			valid=false; //set correctness of output file path to false
			if (outFileName==null){
				JOptionPane.showMessageDialog(null, "You have not entered a destination to save to. Please input a valid file name.");
			}else if(outFileName.equals("")){
				//error message of empty file name
				JOptionPane.showMessageDialog(null, "You have entered an empty file name. Please input a valid file name.");
			}else{
				Matcher m =Pattern.compile(".mp3$").matcher(outFileName);
				if (_curDir.equals(_saveDir)){
					//error message need to not be the same name as input file
					JOptionPane.showMessageDialog(null, "Your input file and output file cannot be the same. Please input a valid file name that is not the same.");
				}else if (m.find()){
					if (FileChecker.fileExist(outFileName)){
						//file exist ask if override
						Object[] option= {"Override","New output file name"};
						//check if the file exist locally
						//note 0 is override ie first option chosen and 1 is new name
						overrideChoice=JOptionPane.showOptionDialog(null, "File " +outFileName +" already exist. Do you wish to override or input new file name?",
								"Override?",JOptionPane.YES_NO_OPTION,JOptionPane.QUESTION_MESSAGE,null,option,option[0]);
						if(overrideChoice==0){
							valid=true;//out file valid
						}
					}else{
						valid=true;//out file valid
					}
				}else{
					//error message need to end with mp3
					JOptionPane.showMessageDialog(null, "You have entered a file name that does not end with .mp3 \nPlease input a valid file name that ends with .mp3");
				}

			}
		}
		
		if(valid){
			//delete to be override file
			if(overrideChoice==0){
				File file=new File(outFileName);
				file.delete();
			}
			//create the gui of extract which consist of cancel and progress bar
			JFrame stripAudioFrame=new JFrame("Strip audio");
			Container pane=stripAudioFrame.getContentPane();
			pane.setLayout(new GridLayout(2,0));
			JButton cancelButton =new JButton("Cancel Strip Audio");
			JProgressBar dlProgressBar=new JProgressBar();
			stripAudioFrame.setSize(300, 100); //set size of frame
			cancelButton.addActionListener(new ActionListener() {
				//setup cancel button listener
				@Override
				public void actionPerformed(ActionEvent e) {
					saWork.cancel(true);
				}
			});
			//add window listener to close button (cross hair) so it cancel as well
			stripAudioFrame.addWindowListener(new WindowAdapter() {
				@Override
				public void windowClosing(WindowEvent e){
					saWork.cancel(true);
				}
			});
			stripAudioFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
			stripAudioFrame.add(cancelButton,pane); //add cancel button to new frame
			stripAudioFrame.add(dlProgressBar,pane); //add progress bar to new frame
			stripAudioFrame.setVisible(true); //set visibility of frame on
			stripAudioFrame.setResizable(false); //set frame so it can't be resize
			//create swing worker object and run it
			saWork=new StripAudioWorker(path+inFileName,outFileName,stripAudioFrame,dlProgressBar);
			saWork.execute();
		}
	}