Improved examples

examples/tutorial_thread/3_user_input_processing_and_output.cpp

@@ -146,7 +146,7 @@ public:
             if (datumsPtr != nullptr && !datumsPtr->empty())
             {
                 cv::imshow("User worker GUI", datumsPtr->at(0).cvOutputData);
-                cv::waitKey(500); // It sleeps 500 ms just to let the user see the output. Change to 33ms for normal 30 fps display
+                cv::waitKey(1); // It displays the image and sleeps at least 1 ms (it usually sleeps ~5-10 msec to display the image)
             }
         }
         catch (const std::exception& e)

examples/tutorial_thread/4_user_input_processing_output_and_datum.cpp

@@ -158,7 +158,7 @@ public:
             if (datumsPtr != nullptr && !datumsPtr->empty())
             {
                 cv::imshow("User worker GUI", datumsPtr->at(0).cvOutputData);
-                cv::waitKey(500); // It sleeps 500 ms just to let the user see the output. Change to 33ms for normal 30 fps display
+                cv::waitKey(1); // It displays the image and sleeps at least 1 ms (it usually sleeps ~5-10 msec to display the image)
             }
         }
         catch (const std::exception& e)

examples/tutorial_wrapper/1_user_asynchronous.cpp

@@ -180,7 +180,7 @@ public:
         if (datumsPtr != nullptr && !datumsPtr->empty())
         {
             cv::imshow("User worker GUI", datumsPtr->at(0).cvOutputData);
-            cv::waitKey(500); // It sleeps 500 ms just to let the user see the output. Change to 33ms for normal 30 fps display
+            cv::waitKey(1); // It displays the image and sleeps at least 1 ms (it usually sleeps ~5-10 msec to display the image)
         }
         else
             op::log("Nullptr or empty datumsPtr found.", op::Priority::Max, __LINE__, __FUNCTION__, __FILE__);

examples/tutorial_wrapper/2_user_synchronous.cpp

@@ -220,7 +220,7 @@ public:
             if (datumsPtr != nullptr && !datumsPtr->empty())
             {
                 cv::imshow("User worker GUI", datumsPtr->at(0).cvOutputData);
-                cv::waitKey(500); // It sleeps 500 ms just to let the user see the output. Change to 33ms for normal 30 fps display
+                cv::waitKey(1); // It displays the image and sleeps at least 1 ms (it usually sleeps ~5-10 msec to display the image)
             }
         }
         catch (const std::exception& e)

src/openpose/producer/webcamReader.cpp

@@ -100,7 +100,7 @@ namespace op
                 else
                 {
                     lock.unlock();
-                    std::this_thread::sleep_for(std::chrono::microseconds{500});
+                    std::this_thread::sleep_for(std::chrono::microseconds{10});
                 }
             }
             return cvMat;