2SR Python API

bob.rppg.ssr.ssr_utils.get_skin_pixels(face_frame, index, facewidth, skininit, threshold, bounding_boxes=None, skin_frame=None, plot=False) → skin_pixels

Get a list of skin colored pixels inside the given frame.

Parameters

face_frame (numpy array):

The frame where the face has to be detected.

index (int):

The index of the frame containing the face to be detected.

skininit (boolean):

Flag if you want the parameters of the skin model to be re-estimated.

threshold (float [0-1]):

The threshold on the skin color probability.

bounding_boxes (list of BoundingBoxes):

The face bounding boxes corresponding to the sequence.

skin_frame (numpy array):

The frame where the skin pixels have to be retrieved. If not set, face_frame will be used.

plot (boolean):

Flag to plot the result of skin pixels detection

Returns

skin_pixels (numpy array):

The RGB values of all detected skin colored pixels

bob.rppg.ssr.ssr_utils.get_eigen(skin_pixels) → eigenvalues, eigenvectors

Build the C matrix, get eigenvalues and eigenvectors, sort them.

Parameters

skin_pixels (numpy array):

The RGB values of skin-colored pixels.

Returns

eigenvalues (numpy array):

The eigenvalues of the correlation matrix

eigenvectors (numpy array):

The (sorted) eigenvectors of the correlation matrix

bob.rppg.ssr.ssr_utils.plot_eigenvectors(skin_pixels, eigenvectors, counter)

Plots skin pixel cluster and eignevectors in the RGB space.

Parameters

skin_pixels (numpy array):

The RGB values of skin-colored pixels.

eigenvectors (numpy array):

The eigenvectors of the correlation matrix.

bob.rppg.ssr.ssr_utils.build_P(counter, temporal_stride, eigenvectors, eigenvalues, plot=False) → p

Builds P

Parameters

counter (int):

The frame index

temporal_stride (int):

The temporal stride to use

eigenvectors (numpy array):

The eigenvectors of the c matrix (for all frames up to counter).

eigenvalues (numpy array):

The eigenvalues of the c matrix (for all frames up to counter).

plot (boolean):

If you want something to be plotted

Returns

p (numpy array):

The p signal to add to the pulse.