Openpose给出错误:无法从另一个线程访问CPU/GPU指针数据

Question

我想初始化一个openose实例，将它保存为一个class字段，这个类实现了一些与grpc相关的逻辑，将监听一个端口，我想从这个端口将请求(一个图像)传递给保存的openpose实例进行检测，然后将检测结果返回给这个端口。

在谷歌之后，我找到了PyOpenpose，并像这样实现了我的设计：

  class PosingServer:
    def __init__(self, setting=PosingSetting):
        self.setting=setting
        self.initNetwork()

    def detect(self, req):
            #detect pose
            net.detectPose(req.image)
            #detect pose
           return net.getKeypoints(net.KeypointType.POSE)[0]

    def initNetwork(self):
        setting = self.setting
        self.net = OP.OpenPose(setting.poseSize, setting.faceHandSize, setting.outSize,\
                               setting.modelType, setting.modelFolder, setting.logLevel,\
                               setting.downloadHeatmaps)

   *****grpc related stuffs*******

在PosingServer运行后，它可以接收rpc请求并执行检测，但这一行：

return net.getKeypoints(net.KeypointType.POSE)[0]

给出错误：

The CPU/GPU pointer data cannot be accessed from a different thread.

Coming from:
- src/openpose/pose/poseExtractor.cpp:checkThread():341
- src/openpose/pose/poseExtractor.cpp:checkThread():345
- src/openpose/pose/poseExtractor.cpp:getPoseKeypoints():265
ERROR    Exception calling application: 
Error:
The CPU/GPU pointer data cannot be accessed from a different thread.

Coming from:
- src/openpose/pose/poseExtractor.cpp:checkThread():341
- src/openpose/pose/poseExtractor.cpp:checkThread():345
- src/openpose/pose/poseExtractor.cpp:getPoseKeypoints():265
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/grpc/_server.py", line 377, in _call_behavior
    return behavior(argument, context), True
  File "server/pose/PosingServer.py", line 81, in carryOut
    return self.detector.detect(req)
  File "server/pose/PosingServer.py", line 40, in detect
    return net.getKeypoints(net.KeypointType.POSE)[0])
RuntimeError: 
Error:
The CPU/GPU pointer data cannot be accessed from a different thread.

如何解决这个问题？

Answer 1

在调用getPoseKeypoints()之前，应该使用函数PoseExtractor::initializationOnThread()对PoseExtractor对象进行初始化。我在开发自己的多线程应用程序时遇到了完全相同的错误，因为初始化是从父线程调用的，而我试图从子线程获取姿势关键点。我通过确保在同一线程中调用这两个函数解决了这个问题。