src/dw/sensors/camera/docs/usecase1.md

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

@page camera_usecase1 Camera Workflow

Initialize the Sensor Abstraction Layer

```{.cpp}
dwSAL_initialize(&sal, sdk);
```

Initialize the parameter string for a camera sensor, in this case we request a processed image (yuv), a camera
ar0231-rccb with sf3324 module and BAE exposure type at group C. We specify a gmsl protocol and create the sensor

```{.cpp}
    dwSensor cameraSensor = DW_NULL_HANDLE;
    dwSensorParams params;
    params.parameters = "output-format=yuv,camera-type=ar0231-rccb-bae-sf3324,camera-group=c";
    params.protocol = "camera.gmsl";
    dwSAL_createSensor(&cameraSensor, params, sal);
```

after starting the sensor, the camera will start acquiring frames

```{.cpp}
dwSensor_start(...);

while(loop) {
```

We read a frame, which is stored as a `::dwCameraFrameHandle_t` and specify a timeout value in microseconds

```{.cpp}
...
    dwCameraFrameHandle_t frameHandle = DW_NULL_HANDLE;
    dwTime_t timeout = 33000;
    dwSensorCamera_readFrame(&frameHandle, timeout, cameraSensor);
...
```

many outputs can be return after reading, the only extra cost are eventual streaming and conversion, depending
on the output chosen. Also the output type is influenced by how we created the camera. Since we specified
processed image (yuv), we can request a processed image as output. In order to know what properties such an image has,
it is possible to call `dwSensorCamera_getImageProperties()` 
with `::dwCameraOutputType` equal to `::DW_CAMERA_OUTPUT_NATIVE_PROCESSED`. 

```{.cpp}
...
    dwImageHandle_t imageNative;
    dwSensorCamera_getImage(&imageNative, DW_CAMERA_IMAGE_OUTPUT_NATIVE_PROCESSED,...);
    dwImageHandle_t imageCUDA_RGBA;
    dwSensorCamera_getImage(&imageCUDA_RGBA, DW_CAMERA_IMAGE_OUTPUT_CUDA_RGBA,...);

    // CODE: use imageNative (maybe send to serializer)
    // CODE: use imageCUDA_RGBA
...
```

return frames to the fifo

```{.cpp}
...
    dwSensorCamera_returnFrame(...);
}
```

stop the sensor and release

```{.cpp}
dwSensor_stop(...);
dwSAL_releaseSensor(&cameraSensor);
```

For more details see:
- @ref dwx_camera_sample