iphone - iOS Camera Overlay Capture Image -

i facing real though issues. have studied couple of tutorial adding overlay in camera using uiimagepickercontroller , avfoundation. working fine me. can add overlay on camera using both. main concern extract part of image under overlay view when user hits scan button. having white view in overlay , button, image under white view should retrieved.

-(ibaction)cameraclicked:(id)sender {      overlayview *overlay = [[overlayview alloc] initwithframe:cgrectmake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];      self.imagepickercontroller = [[uiimagepickercontroller alloc] init];     self.imagepickercontroller.delegate = self;      if ([uiimagepickercontroller      iscameradeviceavailable:uiimagepickercontrollercameradevicerear]) {         self.imagepickercontroller.sourcetype = uiimagepickercontrollersourcetypecamera;         self.imagepickercontroller.cameracapturemode =              uiimagepickercontrollercameracapturemodephoto;     }     else {         self.imagepickercontroller.sourcetype =             uiimagepickercontrollersourcetypesavedphotosalbum;     }      self.imagepickercontroller.showscameracontrols = no;     self.imagepickercontroller.navigationbarhidden = yes;           self.imagepickercontroller.toolbarhidden = yes;      self.imagepickercontroller.wantsfullscreenlayout = yes;     self.imagepickercontroller.cameraviewtransform =          cgaffinetransformscale(self.imagepickercontroller.cameraviewtransform,      camera_transform_x,camera_transform_y);     self.imagepickercontroller.cameraoverlayview = overlay;     [self presentviewcontroller:self.imagepickercontroller animated:yes          completion:nil]; }  - (void)imagepickercontroller:(uiimagepickercontroller *)picker didfinishpickingmediawithinfo:(nsdictionary *)info {     uiimage *image = [info objectforkey:uiimagepickercontrolleroriginalimage];      cgrect croprect;     uiimage *image = [info objectforkey:uiimagepickercontrolleroriginalimage];     uiimage *crosshair = [uiimage imagenamed:@"overlay.png"];      uigraphicsbeginimagecontext(cgsizemake(self.view.frame.size.width, self.view.frame.size.height));     [image drawinrect: cgrectmake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];     uiimage *smallimage = uigraphicsgetimagefromcurrentimagecontext();     uigraphicsendimagecontext();      if(isios7)         croprect = cgrectmake(10, 440, crosshair.size.width, crosshair.size.height);     else         croprect = cgrectmake(10, 405, crosshair.size.width, crosshair.size.height);      cgimageref imageref = cgimagecreatewithimageinrect([smallimage cgimage], croprect);     uiimage *setimage = [uiimage imagewithcgimage:imageref];     self.finalimageview.image = setimage;      [self dismissviewcontrolleranimated:yes completion:nil]; } 

try this... working..

  self.imagepickercontroller=nil;   self.imagepickercontroller = [[uiimagepickercontroller alloc] init];   self.imagepickercontroller.sourcetype = uiimagepickercontrollersourcetypecamera;   self.imagepickercontroller.delegate = self;   self.imagepickercontroller.allowsediting = no;   self.imagepickercontroller.showscameracontrols = no; 

// create view overlay

 cgrect overlayrect = cgrectmake(0, 0, self.imagepickercontroller.view.frame.size.width,      self.imagepickercontroller.view.frame.size.height);      uiview *overlayview = [[uiview alloc] initwithframe:overlayrect];      btn_overlay = [uibutton buttonwithtype:uibuttontypecustom];     [btn_overlay setbackgroundimage:[uiimage imagenamed:@"imagenmae"] forstate:uicontrolstatenormal];     btn_overlay.frame = cgrectmake(80.0, 170, 150.0, 30.0);     btn_overlay.tag = 0;     [btn_overlay settitle:@"button title" forstate:uicontrolstatenormal];     [btn_overlay addtarget:self action:@selector(actinmethod:) forcontrolevents:uicontroleventtouchupinside];     [overlayview addsubview:btn_overlay];  [self.imagepickercontroller setcameraoverlayview:overlayview];     // display imagepicker     [self.navigationcontroller presentviewcontroller:self.imagepickercontroller animated:yes completion:nil];