waitcondition/camera/docs/usecase3.md

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# Copyright (c) 2019-2020, NVIDIA CORPORATION.  All rights reserved.

@page waitcondition_usecase3 Wait Conditions Detector Workflow

@note SW Release Applicability: This tutorial is applicable to modules in **NVIDIA DRIVE Software** releases.

The following code snippet shows the general structure of a program that uses waitconditions detector to detect intersections, traffic lights and traffic signs.

Initialize WaitNet default parameters, WaitNet, detector parameters and then the detector.
```{.cpp}
dwWaitNetParams waitnetParams{};
dwWaitNet_initDefaultParams(&waitnetParams)
dwWaitNet_initialize(&waitnetHandle, &waitnetParams, context);
dwWaitConditionsDetectorParams wcDetectorParams;
dwWaitConditionsDetector_initDefaultParams(&wcDetectorParams);
dwWaitConditionsDetector_initializeFromWaitNetNew(&wcDetectorHandle, waitnetHandle,
                                                  &wcDetectorParams, cam2Rig, calibratedCamObj, motionObj, context);
```

Then bind output and set cuda stream:
```{.cpp}
dwWaitConditionsDetectorOutput detectorOutput{};
dwIntersectionDetection detectedIntersections[DW_WAIT_CONDITIONS_DETECTOR_MAX_INTERSECTIONS];
intersectionsBuffer.buffer   = detectedIntersections;
intersectionsBuffer.size     = 0;
intersectionsBuffer.maxSize  = DW_WAIT_CONDITIONS_DETECTOR_MAX_INTERSECTIONS;
detectorOutput.intersections = &intersectionsBuffer;
dwWaitConditionsDetector_bindOutput(&detectorOutput, wcDetectorHandle);
dwWaitConditionsDetector_setCUDAStream(cudaStream, wcDetectorHandle);
```

Detect intersections, traffic lights and traffic signs:
```{.cpp}
dwWaitConditionsDetector_inferDeviceAsync(&imageIn, imageNum, wcDetectorHandle);
dwWaitConditionsDetector_interpret(imageNum, wcDetectorHandle);
```

When finished, release the module handles:
```{.cpp}
dwWaitConditionsDetector_release(wcDetectorHandle);
dwWaitNet_release(waitnetHandle);
```

For more detailed workflow, please refer to the intersection detector sample: @ref dwx_sample_intersection_detector