# C++ API Documentation ## Estimator class ### class del::DemographicEstimator The Demographic Estimator class #### Constructors ```cpp DemographicEstimator(const std::string& modelFile, int maxConcurrency = 0) ``` Constructor: loads model file, sets up the processing. **Parameters:** - `modelFile` - path for the used model - `maxConcurrency` - maximum allowed concurrency, 0 means automatic (using all cores), default: 0 ```cpp ~DemographicEstimator() ``` Destructor #### Methods ```cpp std::future> detectFaces(const del::ImageHeader& imageHeader) ``` Detects the faces on an image with the std::future API. **Note:** The given ImageHeader doesn't own the image data, and it is safe to delete the data after the call, a copy is happening internally. See del::ImageHeader for details. **Note:** Calling this function is non-blocking, so calling it again with the next image without waiting for the result is possible. Also see getConcurrentCalculations(). **Note:** This is the std::future based API, for callback API see `del::DemographicEstimator::detectFaces(const del::ImageHeader&, std::function>)>)`. **Parameters:** - `imageHeader` - image descriptor --- ```cpp void detectFaces(const del::ImageHeader& imageHeader, std::function>)> callback) ``` Detects the faces on an image with a callback API. **Note:** The given ImageHeader doesn't own the image data, and it is safe to delete the data after the call, a copy is happening internally. See del::ImageHeader for details. **Note:** Calling this function is non-blocking, so calling it again with the next frame without waiting for the result is possible. Also see getConcurrentCalculations(). **Note:** This is the callback based API, for std::future API see `del::DemographicEstimator::detectFaces(const del::ImageHeader&)`. **Parameters:** - `imageHeader` - image descriptor - `callback` - callback to call with the result **Returns:** tracked landmarks and emotions --- ```cpp std::future> estimate(const del::Face& face) ``` Returns the demographic estimation of the detected face. **Note:** Calling this function is non-blocking, so calling it again with the next frame without waiting for the result is possible. Also see getConcurrentCalculations(). **Note:** This is the std::future based API, for callback API see `del::DemographicEstimator::estimate(const del::Face&, std::function>)>)`. **Parameters:** - `face` - the previously detected face to embed **Returns:** estimations --- ```cpp void estimate(const del::Face& face, std::function>)> callback) ``` Returns the demographic estimation of the detected face. **Note:** Calling this function is non-blocking, so calling it again with the next frame without waiting for the result is possible. Also see getConcurrentCalculations(). **Note:** This is the callback based API, for std::future API see `del::DemographicEstimator::estimate(const del::Face&)`. **Parameters:** - `face` - the previously detected face to embed - `callback` - callback to call with the result --- ```cpp int getConcurrentCalculations() const ``` Returns the value of the atomic counter for the number of calculations currently running concurrently. You can use this to limit the number of concurrent calculations. **Returns:** The (approximate) number of calculations currently in-flight. --- ```cpp std::string getModelName() const ``` Returns the name (version etc) of the loaded model. **Returns:** name of the model --- ```cpp static del::Version getSDKVersion() ``` Returns the version of the SDK (and not the model) **Returns:** version of the SDK --- ```cpp static std::string getSDKVersionString() ``` Returns the version string of the SDK (and not the model) **Returns:** version string of the SDK ## Image header class ### struct del::ImageHeader Descriptor class for image data (non-owning) **Members:** - `const uint8_t* data` - pointer to the byte array of the image - `int width` - width of the image in pixels - `int height` - height of the image in pixels - `int stride` - length of one row of pixels in bytes (e.g: 3*width + padding) - `del::ImageFormat format` - image format ### enum class del::ImageFormat **Values:** - `Grayscale = 0` - 8-bit grayscale - `RGB = 1` - 24-bit RGB - `RGBA = 2` - 32-bit RGBA or 32-bit RGB_ - `BGR = 3` - 24-bit BGR - `BGRA = 4` - 32-bit BGRA or 32-bit BGR_ ## Result classes ### Face See also: [landmarks specification](overview.md#target-to-face-specs). #### class del::Face Face Class ##### Constructors ```cpp Face(const del::ImageHeader& imageHeader, const std::vector& landmarks, const del::BoundingBox& bbox = del::BoundingBox(), float confidence = 0.0f) ``` Constructor for the Face object to support 3rd party face detectors **Parameters:** - `imageHeader` - image descriptor - `landmarks` - face landmarks - `bbox` - face bounding box - `confidence` - face detection confidence ```cpp ~Face() ``` Destructor ##### Methods ```cpp BoundingBox boundingBox() const ``` Returns the bounding box of the detected face **Returns:** BoundingBox --- ```cpp float confidence() const ``` Returns the confidence value of the detected face **Returns:** float --- ```cpp std::vector landmarks() const ``` Returns the landmarks of the face **Returns:** std::vector ### Point2d #### struct del::Point2d Point2d class for landmarks **Members:** - `float x` - x coordinate of the point - `float y` - y coordinate of the point ### BoundingBox #### struct del::BoundingBox Bounding Box class for the faces **Members:** - `int x` - x coordinate of the top-left corner - `int y` - y coordinate of the top-left corner - `int width` - width of the bounding box in pixels - `int height` - height of the bounding box in pixels ### OutputType #### enum class del::OutputType Type of the output in Output struct. **Values:** - `AGE = 0` - `GENDER = 1` - `AGE_UNCERTAINTY = 2` ### Gender #### enum class del::Gender Gender enum. **Values:** - `FEMALE = 0` - `MALE = 1` ### Output #### struct del::Output Output struct for various estimated outputs. **Members:** - `del::OutputType type` - type of the output - `std::variant value` - value of the output - `std::string name` - name of the output