本文整理汇总了Python中PyQt5.QtCore.QByteArray.lastIndexOf方法的典型用法代码示例。如果您正苦于以下问题：Python QByteArray.lastIndexOf方法的具体用法？Python QByteArray.lastIndexOf怎么用？Python QByteArray.lastIndexOf使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类PyQt5.QtCore.QByteArray的用法示例。
在下文中一共展示了QByteArray.lastIndexOf方法的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Python代码示例。
示例1: NetworkMJPGImage
# 需要导入模块: from PyQt5.QtCore import QByteArray [as 别名]
# 或者: from PyQt5.QtCore.QByteArray import lastIndexOf [as 别名]
#.........这里部分代码省略.........
def getSourceURL(self) -> "QUrl":
return self._source_url
sourceURLChanged = pyqtSignal()
source = pyqtProperty(QUrl, fget = getSourceURL, fset = setSourceURL, notify = sourceURLChanged)
def setMirror(self, mirror: bool) -> None:
if mirror == self._mirror:
return
self._mirror = mirror
self.mirrorChanged.emit()
self.update()
def getMirror(self) -> bool:
return self._mirror
mirrorChanged = pyqtSignal()
mirror = pyqtProperty(bool, fget = getMirror, fset = setMirror, notify = mirrorChanged)
imageSizeChanged = pyqtSignal()
@pyqtProperty(int, notify = imageSizeChanged)
def imageWidth(self) -> int:
return self._image.width()
@pyqtProperty(int, notify = imageSizeChanged)
def imageHeight(self) -> int:
return self._image.height()
@pyqtSlot()
def start(self) -> None:
self.stop() # Ensure that previous requests (if any) are stopped.
if not self._source_url:
Logger.log("w", "Unable to start camera stream without target!")
return
self._started = True
self._image_request = QNetworkRequest(self._source_url)
if self._network_manager is None:
self._network_manager = QNetworkAccessManager()
self._image_reply = self._network_manager.get(self._image_request)
self._image_reply.downloadProgress.connect(self._onStreamDownloadProgress)
@pyqtSlot()
def stop(self) -> None:
self._stream_buffer = QByteArray()
self._stream_buffer_start_index = -1
if self._image_reply:
try:
try:
self._image_reply.downloadProgress.disconnect(self._onStreamDownloadProgress)
except Exception:
pass
if not self._image_reply.isFinished():
self._image_reply.close()
except Exception as e: # RuntimeError
pass # It can happen that the wrapped c++ object is already deleted.
self._image_reply = None
self._image_request = None
self._network_manager = None
self._started = False
def _onStreamDownloadProgress(self, bytes_received: int, bytes_total: int) -> None:
# An MJPG stream is (for our purpose) a stream of concatenated JPG images.
# JPG images start with the marker 0xFFD8, and end with 0xFFD9
if self._image_reply is None:
return
self._stream_buffer += self._image_reply.readAll()
if len(self._stream_buffer) > 2000000: # No single camera frame should be 2 Mb or larger
Logger.log("w", "MJPEG buffer exceeds reasonable size. Restarting stream...")
self.stop() # resets stream buffer and start index
self.start()
return
if self._stream_buffer_start_index == -1:
self._stream_buffer_start_index = self._stream_buffer.indexOf(b'\xff\xd8')
stream_buffer_end_index = self._stream_buffer.lastIndexOf(b'\xff\xd9')
# If this happens to be more than a single frame, then so be it; the JPG decoder will
# ignore the extra data. We do it like this in order not to get a buildup of frames
if self._stream_buffer_start_index != -1 and stream_buffer_end_index != -1:
jpg_data = self._stream_buffer[self._stream_buffer_start_index:stream_buffer_end_index + 2]
self._stream_buffer = self._stream_buffer[stream_buffer_end_index + 2:]
self._stream_buffer_start_index = -1
self._image.loadFromData(jpg_data)
if self._image.rect() != self._image_rect:
self.imageSizeChanged.emit()
self.update()