Hi,
I have studied face_detector.py from here.
Here detector is applied on video camera frames in real time.
The issue comes after 80-90 frames - the script simply stops, but the application didn't crash.
And I can't figure out why it stops and how I can prevent this?
Any ideas?
# coding: utf-8 from objc_util import * from ctypes import c_void_p import ui import time # 全フレームを処理しようとすると動かなくなるのでこの程度で FRAME_INTERVAL = 6 # 30fps / 6 = 5fps frame_counter = 0 last_fps_time = time.time() fps_counter = 0 AVCaptureSession = ObjCClass('AVCaptureSession') AVCaptureDevice = ObjCClass('AVCaptureDevice') AVCaptureDeviceInput = ObjCClass('AVCaptureDeviceInput') AVCaptureVideoDataOutput = ObjCClass('AVCaptureVideoDataOutput') AVCaptureVideoPreviewLayer = ObjCClass('AVCaptureVideoPreviewLayer') CIImage = ObjCClass('CIImage') CIDetector = ObjCClass('CIDetector') dispatch_get_current_queue = c.dispatch_get_current_queue dispatch_get_current_queue.restype = c_void_p CMSampleBufferGetImageBuffer = c.CMSampleBufferGetImageBuffer CMSampleBufferGetImageBuffer.argtypes = [c_void_p] CMSampleBufferGetImageBuffer.restype = c_void_p CVPixelBufferLockBaseAddress = c.CVPixelBufferLockBaseAddress CVPixelBufferLockBaseAddress.argtypes = [c_void_p, c_int] CVPixelBufferLockBaseAddress.restype = None CVPixelBufferGetWidth = c.CVPixelBufferGetWidth CVPixelBufferGetWidth.argtypes = [c_void_p] CVPixelBufferGetWidth.restype = c_int CVPixelBufferGetHeight = c.CVPixelBufferGetHeight CVPixelBufferGetHeight.argtypes = [c_void_p] CVPixelBufferGetHeight.restype = c_int CVPixelBufferUnlockBaseAddress = c.CVPixelBufferUnlockBaseAddress CVPixelBufferUnlockBaseAddress.argtypes = [c_void_p, c_int] CVPixelBufferUnlockBaseAddress.restype = None def captureOutput_didOutputSampleBuffer_fromConnection_(_self, _cmd, _output, _sample_buffer, _conn): global frame_counter, fps_counter, last_fps_time global image_width, image_height, faces # 性能確認のためビデオデータの実 FPS 表示 fps_counter += 1 now = time.time() if int(now) > int(last_fps_time): label_fps.text = '{:5.2f} fps'.format((fps_counter) / (now - last_fps_time)) last_fps_time = now fps_counter = 0 # 画像処理は FRAME_INTERVAL 間隔で処理 if frame_counter == 0: # ビデオ画像のフレームデータを取得 imagebuffer = CMSampleBufferGetImageBuffer(_sample_buffer) # バッファをロック CVPixelBufferLockBaseAddress(imagebuffer, 0) image_width = CVPixelBufferGetWidth(imagebuffer) image_height = CVPixelBufferGetHeight(imagebuffer) ciimage = CIImage.imageWithCVPixelBuffer_(ObjCInstance(imagebuffer)) # CIDetector により顔検出 options = {'CIDetectorAccuracy': 'CIDetectorAccuracyHigh'} detector = CIDetector.detectorOfType_context_options_('CIDetectorTypeFace', None, options) faces = detector.featuresInImage_(ciimage) # バッファのロックを解放 CVPixelBufferUnlockBaseAddress(imagebuffer, 0) # 検出した顔の情報を使って表示を更新 path_view.set_needs_display() frame_counter = (frame_counter + 1) % FRAME_INTERVAL class PathView(ui.View): def __init__(self, *args, **kwargs): super().__init__(*args, **kwargs) def draw(self): # 検出した顔の輪郭に合わせて、表示を加工 if faces is not None and faces.count() != 0: # 顔の部分を白く覆う ui.set_color((1, 1, 1, 0.9)) for face in faces: face_bounds = face.bounds() # カメラの画像は X軸=1920 Y軸=1080 # View は X軸=375 Y軸=667 # 画像のX軸Y軸をViewのY軸X軸に対応させ、サイズを調整 x = face_bounds.origin.y * self.height / image_width y = face_bounds.origin.x * self.width / image_height w = face_bounds.size.height * self.height / image_width h = face_bounds.size.width * self.width / image_height path = ui.Path.oval(x, y, w * 1.3, h) path.fill() @on_main_thread def main(): global path_view, label_fps, faces # 画面の回転には対応しておらず # iPhoneの画面縦向きでロックした状態で、横長画面で使う想定 # View のサイズは手持ちの iPhone6 に合わせたもの faces = None main_view = ui.View(frame=(0, 0, 375, 667)) path_view = PathView(frame=main_view.frame) main_view.name = 'Face Detector' sampleBufferDelegate = create_objc_class( 'sampleBufferDelegate', methods=[captureOutput_didOutputSampleBuffer_fromConnection_], protocols=['AVCaptureVideoDataOutputSampleBufferDelegate']) delegate = sampleBufferDelegate.new() session = AVCaptureSession.alloc().init() device = AVCaptureDevice.defaultDeviceWithMediaType_('vide') _input = AVCaptureDeviceInput.deviceInputWithDevice_error_(device, None) if _input: session.addInput_(_input) else: print('Failed to create input') return output = AVCaptureVideoDataOutput.alloc().init() queue = ObjCInstance(dispatch_get_current_queue()) output.setSampleBufferDelegate_queue_(delegate, queue) output.alwaysDiscardsLateVideoFrames = True session.addOutput_(output) session.sessionPreset = 'AVCaptureSessionPresetHigh' # 1920 x 1080 prev_layer = AVCaptureVideoPreviewLayer.layerWithSession_(session) prev_layer.frame = ObjCInstance(main_view).bounds() prev_layer.setVideoGravity_('AVLayerVideoGravityResizeAspectFill') ObjCInstance(main_view).layer().addSublayer_(prev_layer) # 性能確認のためビデオデータの実 FPS 表示 label_fps = ui.Label(frame=(0, 0, main_view.width, 30), flex='W', name='fps') label_fps.background_color = (0, 0, 0, 0.5) label_fps.text_color = 'white' label_fps.text = '' label_fps.alignment = ui.ALIGN_CENTER main_view.add_subview(label_fps) main_view.add_subview(path_view) session.startRunning() main_view.present('sheet') main_view.wait_modal() session.stopRunning() delegate.release() session.release() output.release() if __name__ == '__main__': main()