ios - How to add Image to video using GPUImage in Swift -

i have codes add image video using gpuimage, somehow doesn't work thought. have searched solution, , still have problem.
i'm trying merge image when recoding done. output video not image.
here's code.

override func viewdidload(){    super.viewdidload     setupcamera() }  func setupcamera(){     let myboundsize: cgsize = uiscreen.mainscreen().bounds.size      camerasubpreview = gpuimageview(frame: cgrectmake(0, 0, myboundsize.width, myboundsize.height))     camerainput = gpuimagevideocamera(sessionpreset: avcapturesessionpreset1280x720, cameraposition: .front)     camerainput.horizontallymirrorfrontfacingcamera = true     camerainput.outputimageorientation = .portrait      camerainput.addtarget(mainvideofilter)      mainvideofilter.addtarget(camerasubpreview)     camerapreview.addsubview(camerasubpreview)     camerainput.startcameracapture() }  func setupfilter(){      let logoimageforgpu = gpuimagepicture(image: logoimageview.image)       logoimageforgpu.addtarget(transformfilter)      logoimageforgpu.processimage()       // apply transform filter      let tx: cgfloat = logoimageview.frame.size.width      let ty: cgfloat = logoimageview.frame.size.height      print("tx , ty: \(tx), \(ty)")      let t: cgaffinetransform = cgaffinetransformmakescale(tx, ty);      transformfilter.affinetransform = t      transformfilter.addtarget(mainvideofilter, attexturelocation: 1) }  func startrecordingvideo(sender: anyobject) {         if(sender.state == uigesturerecognizerstate.began) {             if !self.isrecording {              setupfilter()              let ud = nsuserdefaults.standarduserdefaults()             var intforfilepath : int? = ud.objectforkey("intforfilepath") as? int             if intforfilepath == nil{                 intforfilepath = 10000             }              let paths = nssearchpathfordirectoriesindomains(.documentdirectory, .userdomainmask, true)             let documentsdirectory = paths[0]             intforfilepath = intforfilepath! + 1             let filepath : string? = "\(documentsdirectory)/temp\(intforfilepath!).mp4"             ud.setobject(intforfilepath, forkey: "intforfilepath")             // url.             let fileurl : nsurl = nsurl(fileurlwithpath: filepath!)              //print(filepath)             self.delegate.filepathforvideo = filepath!              moviewriter = gpuimagemoviewriter(movieurl: fileurl, size: cgsize(width: 480, height: 800))             moviewriter.shouldpassthroughaudio = true             //camerainput.addtarget(stillimagefilter)             //print("sif: \()")             stillimagefilter.addtarget(moviewriter)             camerainput.audioencodingtarget = moviewriter              // start recording             moviewriter.startrecording()              circle.hidden = false             drawcircleanimation("strokeend", animename: "updategageanimation", fromvalue: 0.0, tovalue: 1.0, duration: 10.0, repeat: 1, flag: false)              self.isrecording = true         }     } else if (sender.state == uigesturerecognizerstate.ended) {         if self.isrecording {             //stop recording             moviewriter.finishrecording()              stopcircleanimation()             self.isrecording = false              self.movetovideosaveview()         }     } } 

if have ideas solve this, please let me know.
in advance.