scanner.py 文件源码

def _load_input_videos(self):
        """ Opens and checks that all input video files are valid, can
        be processed, and have the same resolution and framerate. """
        self.video_resolution = None
        self.video_fps = None
        self.frames_total = 0
        if not len(self.video_paths) > 0:
            return False
        for video_path in self.video_paths:
            cap = cv2.VideoCapture()
            cap.open(video_path)
            video_name = os.path.basename(video_path)
            if not cap.isOpened():
                if not self.suppress_output:
                    print("[DVR-Scan] Error: Couldn't load video %s." % video_name)
                    print("[DVR-Scan] Check that the given file is a valid video"
                          " clip, and ensure all required software dependencies"
                          " are installed and configured properly.")
                cap.release()
                return False
            curr_resolution = (int(cap.get(cv2.CAP_PROP_FRAME_WIDTH)),
                               int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT)))
            curr_framerate = cap.get(cv2.CAP_PROP_FPS)
            self.frames_total += cap.get(cv2.CAP_PROP_FRAME_COUNT)
            cap.release()
            if self.video_resolution is None and self.video_fps is None:
                self.video_resolution = curr_resolution
                self.video_fps = curr_framerate
                if not self.suppress_output:
                    print("[DVR-Scan] Opened video %s (%d x %d at %2.3f FPS)." % (
                        video_name, self.video_resolution[0],
                        self.video_resolution[1], self.video_fps))
            # Check that all other videos specified have the same resolution
            # (we'll assume the framerate is the same if the resolution matches,
            # since the VideoCapture FPS information is not always accurate).
            elif curr_resolution != self.video_resolution:
                if not self.suppress_output:
                    print("[DVR-Scan] Error: Can't append clip %s, video resolution"
                          " does not match the first input file." % video_name)
                return False
            else:
                if not self.suppress_output:
                    print("[DVR-Scan] Appended video %s." % video_name)
        # If we get to this point, all videos have the same parameters.
        return True