C++ API Documentation

Estimator class

class DemographicEstimator

The Demographic Estimator class.

Public Functions

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

~DemographicEstimator()

Destructor.

std::future<std::vector<del::Face>> 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<void (ResultOrError<std::vector<Face>>)>).

Parameters

  • imageHeader: image descriptor

void detectFaces(const del::ImageHeader &imageHeader, std::function<void(ResultOrError<std::vector<Face>>)> 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&).

Return

tracked landmarks and emotions

Parameters

  • imageHeader: image descriptor

  • callback: callback to call with the result

std::future<std::vector<del::Output>> 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<void (ResultOrError<std::vector<del::Output>>)>).

Return

estimations

Parameters

  • face: the previously detected face to embed

void estimate(const del::Face &face, std::function<void(ResultOrError<std::vector<del::Output>>)> 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

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.

Return

The (approximate) number of calculations currently in-flight.

std::string getModelName() const

Returns the name (version etc) of the loaded model.

Return

name of the model

Public Static Functions

static del::Version getSDKVersion()

Returns the version of the SDK (and not the model)

Return

version of the SDK

static std::string getSDKVersionString()

Returns the version string of the SDK (and not the model)

Return

version string of the SDK

Image header class

struct ImageHeader

Descriptor class for image data (non-owning)

Public 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 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.

class Face

Face Class.

Public Functions

Face(const del::ImageHeader &imageHeader, const std::vector<del::Point2d> &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

~Face()

Destructor.

BoundingBox boundingBox() const

Returns the bounding box of the detected face.

Return

BoundingBox

float confidence() const

Returns the confidence value of the detected face.

Return

float

std::vector<del::Point2d> landmarks() const

Returns the landmarks of the face.

Return

std::vector<del::Point2d>

Point2d

struct Point2d

Point2d class for landmarks.

Public Members

float x

x coordinate of the point

float y

y coordinate of the point

BoundingBox

struct BoundingBox

Bounding Box class for the faces.

Public 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 del::OutputType

Type of the output in Output struct.

Values:

AGE = 0
GENDER = 1

Gender

enum del::Gender

Gender enum.

Values:

FEMALE = 0
MALE = 1

Output

struct Output

Output struct for various estimated outputs.

Public Members

del::OutputType type

type of the output

std::variant<Gender, float> value

value of the output

std::string name

name of the output