init

surround_view/base_thread.py

@@ -0,0 +1,52 @@
+from queue import Queue
+import cv2
+from PyQt5.QtCore import (QThread, QTime, QMutex, pyqtSignal, QMutexLocker)
+
+from .structures import ThreadStatisticsData
+
+
+class BaseThread(QThread):
+
+    """
+    Base class for all types of threads (capture, processing, stitching, ...,
+    etc). Mainly for collecting statistics of the threads.
+    """
+
+    FPS_STAT_QUEUE_LENGTH = 32
+
+    update_statistics_gui = pyqtSignal(ThreadStatisticsData)
+
+    def __init__(self, parent=None):
+        super(BaseThread, self).__init__(parent)
+        self.init_commons()
+
+    def init_commons(self):
+        self.stopped = False
+        self.stop_mutex = QMutex()
+        self.clock = QTime()
+        self.fps = Queue()
+        self.processing_time = 0
+        self.processing_mutex = QMutex()
+        self.fps_sum = 0
+        self.stat_data = ThreadStatisticsData()
+
+    def stop(self):
+        with QMutexLocker(self.stop_mutex):
+            self.stopped = True
+
+    def update_fps(self, dt):
+        # add instantaneous fps value to queue
+        if dt > 0:
+            self.fps.put(1000 / dt)
+
+        # discard redundant items in the fps queue
+        if self.fps.qsize() > self.FPS_STAT_QUEUE_LENGTH:
+            self.fps.get()
+
+        # update statistics
+        if self.fps.qsize() == self.FPS_STAT_QUEUE_LENGTH:
+            while not self.fps.empty():
+                self.fps_sum += self.fps.get()
+
+            self.stat_data.average_fps = round(self.fps_sum / self.FPS_STAT_QUEUE_LENGTH, 2)
+            self.fps_sum = 0