Method And Apparatus Of Adaptive Infrared Projection Control

Abstract

Various examples with respect to adaptive infrared (IR) projection control for depth estimation in computer vision are described. A processor or control circuit of an apparatus receives data of an image based on sensing by one or more image sensors. The processor or control circuit also detects a region of interest (ROI) in the image. The processor or control circuit then adaptively controls a light projector with respect to projecting light toward the ROI.

What is claimed is: 
     
         1 . A method, comprising:
 receiving data of an image based on sensing by one or more image sensors;   detecting a region of interest (ROI) in the image; and   adaptively controlling a light projector with respect to projecting light toward the ROI.   
     
     
         2 . The method of  claim 1 , wherein the receiving of the data of the image comprises receiving data of an infrared (IR) image, a red-green-blue (RGB) image or a depth map. 
     
     
         3 . The method of  claim 1 , wherein:
 the detecting of the ROI in the image comprises detecting a face in the image, and   the adaptively controlling of the light projector with respect to projecting the light toward the ROI comprises:
 enabling an infrared (IR) projector to project an IR light toward the face during a first portion of a sensor readout time when the one or more image sensors read a portion of the image where the ROI is located; and 
 disabling the IR projector to cease projecting the IR light toward the face during a second portion of the sensor readout time when the one or more image sensors read another portion of the image where the ROI is not located. 
   
     
     
         4 . The method of  claim 3 , wherein the enabling of the light projector to project the IR light toward the face during the first portion of the sensor readout time when the one or more image sensors read the portion of the image where the ROI is located comprises disabling the light projector to cease projecting the IR light when the one or more image sensors read a portion of the image where an eye of the face is located. 
     
     
         5 . The method of  claim 1 , wherein:
 the detecting of the ROI in the image comprises:
 detecting a face in the image; and 
 detecting an eye on the face, and 
   the adaptively controlling of the light projector with respect to projecting the light toward the ROI comprises:
 enabling an infrared (IR) projector to project an IR light toward the face responsive to the eye being closed or blinked; and 
 disabling the IR projector to cease projecting the IR light toward the face responsive to the eye being open. 
   
     
     
         6 . The method of  claim 1 , wherein:
 the detecting of the ROI in the image comprises:
 detecting a face in the image; 
 detecting an eye on the face; and 
 monitoring a pupil of the eye, and 
   the adaptively controlling of the light projector with respect to projecting the light toward the ROI comprises controlling an infrared (IR) projector to reduce an amount of power in projecting an IR light toward the face responsive to an enlargement of the pupil.   
     
     
         7 . The method of  claim 1 , wherein:
 the detecting of the ROI in the image comprises:
 detecting a face in the image; and 
 determining a distance of the face from the one or more image sensors based on a size of the face in the image, and 
   the adaptively controlling of the light projector with respect to projecting the light toward the ROI comprises controlling an infrared (IR) projector to reduce an amount of power in projecting an IR light toward the face responsive to the distance of the face being lower than a threshold.   
     
     
         8 . The method of  claim 1 , further comprising:
 detecting a brightness level of an ambient light,   wherein the adaptively controlling of the light projector with respect to projecting the light toward the ROI comprises controlling an infrared (IR) projector to reduce an amount of power in projecting an IR light responsive to the brightness level of the ambient light being lower than a threshold.   
     
     
         9 . The method of  claim 1 , wherein:
 the receiving of the data of the image comprises receiving data of a depth map of the ROI, and   the adaptively controlling of the light projector with respect to projecting the light toward the ROI comprises:
 determining a respective confidence level for each of a plurality of regions of the depth map; and 
 enabling an infrared (IR) projector to project an IR light toward the ROI for each of one or more regions of the plurality of regions of the depth map the respective confidence level of which being lower than a threshold. 
   
     
     
         10 . The method of  claim 1 , wherein the adaptively controlling of the light projector with respect to projecting the light toward the ROI comprises:
 determining a respective amount of texture for each of a plurality of regions of the ROI in the image; and   enabling an infrared (IR) projector to project an IR light toward the ROI for each of one or more regions of the plurality of regions of the ROI the respective amount of texture of which being lower than a threshold.   
     
     
         11 . The method of  claim 1 , wherein the adaptively controlling of the light projector with respect to projecting the light toward the ROI comprises:
 detecting a power level of a battery that powers the light projector; and   controlling an infrared (IR) projector to reduce an amount of power in projecting an IR light toward the ROI responsive to the power level of the battery being lower than a threshold.   
     
     
         12 . An apparatus, comprising:
 a processor or control circuit which, during operation, performs operations comprising:
 receiving data of an image based on sensing by one or more image sensors; 
 detecting a region of interest (ROI) in the image; and 
 adaptively controlling a light projector with respect to projecting light toward the ROI. 
   
     
     
         13 . The apparatus of  claim 12 , wherein the receiving of the data of the image comprises receiving data of an infrared (IR) image, a red-green-blue (RGB) image or a depth map. 
     
     
         14 . The apparatus of  claim 12 , wherein:
 in detecting the ROI in the image, the processor or control circuit detects a face in the image, and   in adaptively controlling the light projector with respect to projecting the light toward the ROI, the processor or control circuit performs operations comprising:
 enabling an infrared (IR) projector to project an IR light toward the face during a first portion of a sensor readout time when the one or more image sensors read a portion of the image where the ROI is located; and 
 disabling the IR projector to cease projecting the IR light toward the face during a second portion of the sensor readout time when the one or more image sensors read another portion of the image where the ROI is not located, 
   wherein, in enabling the light projector to project the IR light toward the face during the first portion of the sensor readout time when the one or more image sensors read the portion of the image where the ROI is located, the processor or control circuit disables the light projector to cease projecting the IR light when the one or more image sensors read a portion of the image where an eye of the face is located.   
     
     
         15 . The apparatus of  claim 12 , wherein:
 in detecting the ROI in the image, the processor or control circuit performs operations comprising:
 detecting a face in the image; and 
 detecting an eye on the face, and 
   in adaptively controlling the light projector with respect to projecting the light toward the ROI, the processor or control circuit performs operations comprising:
 enabling an infrared (IR) projector to project an IR light toward the face responsive to the eye being closed or blinked; 
 controlling the IR projector to reduce an amount of power in projecting the IR light toward the face responsive to an enlargement of a pupil of the eye; and 
 disabling the IR projector to cease projecting the IR light toward the face responsive to the eye being open. 
   
     
     
         16 . The apparatus of  claim 12 , wherein:
 in detecting the ROI in the image, the processor or control circuit performs operations comprising:
 detecting a face in the image; and 
 determining a distance of the face from the one or more image sensors based on a size of the face in the image, and 
   in adaptively controlling of the light projector with respect to projecting the light toward the ROI, the processor or control circuit controls an infrared (IR) projector to reduce an amount of power in projecting an IR light toward the face responsive to the distance of the face being lower than a threshold.   
     
     
         17 . The apparatus of  claim 12 , wherein, during operation, the processor or control circuit further detects a brightness level of an ambient light, and wherein, in adaptively controlling the light projector with respect to projecting the light toward the ROI, the processor or control circuit controls an infrared (IR) projector to reduce an amount of power in projecting an IR light responsive to the brightness level of the ambient light being lower than a threshold. 
     
     
         18 . The apparatus of  claim 12 , wherein:
 in receiving the data of the image, the processor or control circuit receives data of a depth map of the ROI, and   in adaptively controlling the light projector with respect to projecting the light toward the ROI, the processor or control circuit performs operations comprising:
 determining a respective confidence level for each of a plurality of regions of the depth map; and 
 enabling an infrared (IR) projector to project an IR light toward the ROI for each of one or more regions of the plurality of regions of the depth map the respective confidence level of which being lower than a threshold. 
   
     
     
         19 . The apparatus of  claim 12 , wherein, in adaptively controlling the light projector with respect to projecting the light toward the ROI, the processor or control circuit performs operations comprising:
 determining a respective amount of texture for each of a plurality of regions of the ROI in the image; and   enabling an infrared (IR) projector to project an IR light toward the ROI for each of one or more regions of the plurality of regions of the ROI the respective amount of texture of which being lower than a threshold.   
     
     
         20 . The apparatus of  claim 12 , wherein, in adaptively controlling the light projector with respect to projecting the light toward the ROI, the processor or control circuit performs operations comprising:
 detecting a power level of a battery that powers the light projector; and   controlling an infrared (IR) projector to reduce an amount of power in projecting an IR light toward the ROI responsive to the power level of the battery being lower than a threshold.