# SegmentationMask

SegmentationParser node outputs this message. It contains a single-channel segmentation mask, where each pixel value corresponds
to the class label of the segmented object at that location. The mask is represented as a byte array where the value 255 is
reserved for the pixels that do not belong to any class, and the values from 0 to 254 are used for the actual class labels. For
example, in a binary segmentation task, the "background" class would be represented by 255 and the "object" class would be
represented by 0.

## Examples of functionality

 * [Segmentation Parser](https://docs.luxonis.com/software-v3/depthai/depthai-components/nodes/segmentation_parser.md) - Run a
   DeepLabv3+ segmentation model and display the resulting segmentation mask on a video stream.

## Reference

### dai::SegmentationMask

Kind: class

SegmentationMask message. Segmentation mask of an image is stored as a single-channel UINT8 array, where each value represents a
class or instance index. The value 255 is treated as background pixels (no class/instance).

#### std::optional< ImgTransformation > transformation

Kind: variable

#### SegmentationMask()

Kind: function

#### SegmentationMask(const std::vector< std::uint8_t > & data, size_t width, size_t height)

Kind: function

#### ~SegmentationMask()

Kind: function

#### void serialize(std::vector< std::uint8_t > & metadata, DatatypeEnum & datatype)

Kind: function

#### DatatypeEnum getDatatype()

Kind: function

Get the datatype of this specific message.

return: DatatypeEnum

#### void setSize(size_t width, size_t height)

Kind: function

Sets the size of the segmentation mask. note: Use with caution as it sets the metadata of the mask without allocating or resizing
the underlying data array.

#### std::size_t getWidth()

Kind: function

Returns the width of the segmentation mask.

#### std::size_t getHeight()

Kind: function

Returns the height of the segmentation mask.

#### void setMask(const std::vector< std::uint8_t > & mask, size_t width, size_t height)

Kind: function

Sets the segmentation mask from a vector of bytes. The size of the vector must be equal to width * height.

#### void setMask(dai::ImgFrame & frame)

Kind: function

Sets the segmentation mask from an ImgFrame . parameters: frame: Frame must be of type GRAY8

#### void setMask(span< const std::uint8_t > mask, size_t width, size_t height)

Kind: function

Sets the segmentation mask from a byte span without an extra temporary vector. The span size must be equal to width * height.

#### span< std::uint8_t > prepareMask(size_t width, size_t height)

Kind: function

Prepares internal storage for writing and returns a mutable view to it. The caller must fill exactly width * height bytes.

#### void setLabels(const std::vector< std::string > & labels)

Kind: function

Sets the class labels associated with the segmentation mask. The label at index parameters: labels: Vector of class labels

#### std::vector< std::uint8_t > getMaskData()

Kind: function

Returns a copy of the segmentation mask data as a vector of bytes. If mask data is not set, returns an empty vector.

#### dai::ImgFrame getFrame()

Kind: function

Returns the segmentation mask as an ImgFrame . If mask data is not set, returns an empty frame with only metadata set.

#### std::optional< uint32_t > getArea(uint8_t index)

Kind: function

Returns the area (number of pixels) of the specified instance/class index in the segmentation mask. parameters: index:
Instance/Class index note: If index is not present in the mask, returns std::nullopt.

#### std::optional< dai::Point2f > getCentroid(uint8_t index)

Kind: function

Returns the normalized centroid (x,y) coordinates of the specified instance/class index in the segmentation mask. parameters:
index: Instance/Class index note: If index is not present in the mask, returns std::nullopt.

#### std::vector< uint8_t > getUniqueIndices()

Kind: function

Returns a list of sorted unique indices present in the segmentation mask.

#### std::vector< std::string > getLabels()

Kind: function

Returns all class labels associated with the segmentation mask. If no labels are set, returns an empty vector.

#### std::vector< std::uint8_t > getMaskByIndex(uint8_t index)

Kind: function

Returns a binary mask where pixels belonging to the specified instance/class index are set to 1, others to 0. If mask data is not
set, returns an empty vector.

#### std::vector< std::uint8_t > getMaskByLabel(const std::string & label)

Kind: function

Returns a binary mask where pixels belonging to the specified class label are set to 1, others to 0. If labels are not set or
label not found, returns an empty vector.

#### bool hasValidMask()

Kind: function

Returns true if the mask data is not empty and has valid size (width * height).

#### void setCvMask(cv::Mat mask)

Kind: function

note: This API only available if OpenCV support is enabled Copies cv::Mat data to Segmentation Mask buffer parameters: frame:
Input cv::Mat frame from which to copy the data note: Throws if mask is not a single channel INT8 type.

#### cv::Mat getCvMask(cv::MatAllocator * allocator)

Kind: function

Retrieves mask data as a cv::Mat copy with specified width and height. If mask data is not set, returns an empty matrix.
parameters: allocator: Allows callers to supply a custom cv::MatAllocator for zero-copy/custom memory management; nullptr uses
OpenCV’s default.

#### cv::Mat getCvMaskByIndex(uint8_t index, cv::MatAllocator * allocator)

Kind: function

Returns a binary mask where pixels belonging to the instance index are set to 1, others to 0. If mask data is not set, returns an
empty matrix. parameters: index: Instance index; allocator: Allows callers to supply a custom cv::MatAllocator for
zero-copy/custom memory management; nullptr uses OpenCV’s default.

#### std::vector< std::vector< dai::Point2f > > getContour(uint8_t index)

Kind: function

Calls the opencv findContours function and filters the results based on the provided index. Returns filtered contour as a vector
of vectors of non-normalized points. If mask data is not set, returns an empty vector. parameters: index: class index

#### std::vector< dai::RotatedRect > getBoundingBoxes(uint8_t index, bool calculateRotation)

Kind: function

Returns a bounding box for each continuous region with the specified index. parameters: index: class index; calculateRotation: If
true, returns rotated bounding boxes, otherwise returns the outer, axis-aligned bounding boxes.

#### DEPTHAI_SERIALIZE(SegmentationMask, Buffer::ts, Buffer::tsDevice, Buffer::sequenceNum, transformation, width, height, labels)

Kind: function

### Need assistance?

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