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docs/src/data/get_depth.rst

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+.. _get_depth:
+
+Get depth image
+===============
+
+Depth images belongs to the upper layer of synthetic data. You need to start the ``EnableStreamData()`` beforehand, to get it through ``GetStreamData()``. In addition, it should be check not be empty before use.
+
+For detailed process description, please see :ref:`get_stereo` :ref:`get_stereo_rectified`.
+
+In addition, it is recommended to use plugins to calculate depth: Depth images work better and operate faster. Please refer to :ref:`get_with_plugin`.
+
+Reference code snippet:
+
+.. code-block:: c++
+
+  auto &&api = API::Create(argc, argv);
+
+  api->EnableStreamData(Stream::DEPTH);
+
+  api->Start(Source::VIDEO_STREAMING);
+
+  cv::namedWindow("frame");
+  cv::namedWindow("depth");
+
+  while (true) {
+    api->WaitForStreams();
+
+    auto &&left_data = api->GetStreamData(Stream::LEFT);
+    auto &&right_data = api->GetStreamData(Stream::RIGHT);
+
+    cv::Mat img;
+    cv::hconcat(left_data.frame, right_data.frame, img);
+    cv::imshow("frame", img);
+
+    auto &&depth_data = api->GetStreamData(Stream::DEPTH);
+    if (!depth_data.frame.empty()) {
+      cv::imshow("depth", depth_data.frame);  // CV_16UC1
+    }
+
+    char key = static_cast<char>(cv::waitKey(1));
+    if (key == 27 || key == 'q' || key == 'Q') {  // ESC/Q
+      break;
+    }
+  }
+
+  api->Stop(Source::VIDEO_STREAMING);
+
+The above code uses OpenCV to display the image. When the display window is selected, pressing ``ESC/Q`` will end the program.
+
+Complete code examples, see `get_depth.cc <https://github.com/slightech/MYNT-EYE-S-SDK/blob/master/samples/tutorials/data/get_depth.cc>`_ .
+
+.. tip::
+
+Preview the value of a region of the depth image, see `get_depth_with_region.cc <https://github.com/slightech/MYNT-EYE-S-SDK/blob/master/samples/api/get_depth_with_region.cc>`_ .