iphone camera shuttering sound turning off

Hi. I just need to turn off camera shuttering sound when I capture image from camera in objective-c. Please bid only if you already did this. Put "I already have turned off shuttering sound" in your bid. thanks Here is part of my code: AVCaptureConnection *stillImageConn = [avCaptureStillOutput connectionWithMediaType:AVMediaTypeVideo]; UIDeviceOrientation devOrient = [[UIDevice currentDevice] orientation]; AVCaptureVideoOrientation avOrient = AVCaptureVideoOrientationPortrait; if (devOrient==UIDeviceOrientationLandscapeLeft) avOrient = AVCaptureVideoOrientationLandscapeRight; else if (devOrient==UIDeviceOrientationLandscapeRight) avOrient = AVCaptureVideoOrientationLandscapeLeft; [stillImageConn setVideoOrientation:avOrient]; [avCaptureStillOutput setOutputSettings:[NSDictionary dictionaryWithObject:[NSNumber numberWithInt:kCMPixelFormat_32BGRA] forKey:(id)kCVPixelBufferPixelFormatTypeKey]]; [avCaptureStillOutput captureStillImageAsynchronouslyFromConnection:stillImageConn completionHandler:^(CMSampleBufferRef imageDataSampleBuffer, NSError *error) ..............