Apparatus and method for estimating bio-information
An apparatus for non-invasively estimating bio-information is provided. According to one exemplary embodiment, the apparatus may include a bio-signal acquirer configured to acquire a bio-signal; and a processor configured to extract a plurality of characteristic points from the bio-signal, determine internally dividing points of the plurality of characteristic points, and extract feature values from the bio-signal based on the internally dividing points to perform bio-information estimation.
1. An apparatus for estimating bio-information, the apparatus comprising:
a photoplethysmogram (PPG) sensor or a communication interface configured to acquire a bio-signal of a user;
a processor configured to apply weights to time values of a plurality of characteristic points of the bio-signal, respectively, determine internally dividing points of the plurality of characteristic points based on a sum of the weights, and extract feature values from the bio-signal based on the internally dividing points to perform bio-information estimation; and
a display configured to display a graph of the bio-information which has been measured over time, and display a mark configured to move along the graph according to a user input to allow the user to select a specific data point from the graph.
2. The apparatus of claim 1 , wherein the processor is further configured to apply the weights respectively to the time values based on amplitude values of the plurality of characteristic points.
3. The apparatus of claim 1 , wherein the processor is further configured to estimate the bio-information comprising at least one of blood pressure, vascular age, arterial stiffness, aortic pressure waveform, stress index, and fatigue based on the extracted feature values.
4. The apparatus of claim 1 , wherein the processor is further configured to extract, as the plurality of characteristic points, at least one of points associated with component pulses constituting the bio-signal, a point at which an amplitude has a maximum value in a systolic region of the bio-signal, an area of the bio-signal, and a point in a predetermined region of the bio-signal where a first derivative value is closest to zero.
5. The apparatus of claim 4 , wherein the processor is further configured to determine local minimum points in a second derivative signal of the bio-signal as the points associated with the component pulses.
6. The apparatus of claim 4 , wherein the processor is further configured to extract the feature values based on at least one of a ratio of the area of the bio-signal to an amplitude value at the point at which the amplitude has the maximum value in the systolic region of the bio-signal and a difference in time value between the internally dividing points acquired from each of the systolic region and a diastolic region of the bio-signal.
7. The apparatus of claim 1 , wherein the PPG sensor is configured to emit a light to an object and acquire a PPG signal by detecting the light reflected or scattered from the object.
8. The apparatus of claim 1 , wherein the communication interface is configured to receive a PPG signal from an external device as the bio-signal.
9. The apparatus of claim 1 , wherein the PPG sensor comprises a light source configured to emit a light to an object and a detector configured to detect the light scattered or reflected from the object, and
wherein the PPG sensor acquires the bio-signal from the light detected by the detector.
10. A method of estimating bio-information, the method comprising:
acquiring a bio-signal of a user via a photoplethysmogram (PPG) sensor or a communication interface;
apply weights to time values of a plurality of characteristic points of the bio-signal, respectively;
determining internally dividing points of the plurality of characteristic points based on a sum of the weights;
extracting feature values from the bio-signal based on the internally dividing points to perform bio-information estimation;
displaying a graphic user interface configured to display a graph of the bio-information which has been measured over time, and display a mark configured to move along the graph according to a user input to allow the user to select a specific data point from the graph.
11. The method of claim 10 , wherein the determining the internally dividing points comprises applying the weights respectively to the time values based on amplitude values of the plurality of characteristic points.
12. The method of claim 10 , further comprising estimating the bio-information, which comprises at least one of blood pressure, vascular age, arterial stiffness, aortic pressure waveform, stress index, and fatigue, based on the extracted feature values.
13. The method of claim 10 , further comprising extracting, as the plurality of characteristic points, at least one of points associated with component pulses constituting the bio-signal, a point at which an amplitude has a maximum value in a systolic region of the bio-signal, an area of the bio-signal, and a point in a predetermined region of the bio-signal where a first derivative value is closest to zero.
14. The method of claim 13 , wherein the extracting of the plurality of characteristic points includes determining local minimum points in a second derivative signal of the bio-signal as the points associated with the component pulses.
15. The method of claim 13 , wherein the extracting the feature values comprises extracting the feature values based on at least one of a ratio of the area of the bio-signal to an amplitude value at the point at which the amplitude has the maximum value in the systolic region of the bio-signal and a difference in time value between the internally dividing points acquired from each of the systolic region and a diastolic region of the bio-signal.