Patent ID: 11886647
Assignee: SHANGHAI JIAO TONG UNIVERSITY
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 0:
1. An in-air gesture control method based on visible light signals, comprising a light signal is emitted through a display device and its reflection signal with gestures is collected, and after analysis, gesture recognition is realized and used to generate corresponding control instructions, wherein: emitted light signals are in visible light bands;, a spatial resolution information in the display device to reduce user's visual effect;, wherein the analysis comprises the following steps:
i) performing short-time Fourier transform on reflected signals to convert data in time domain into frequency domain, amplitude sequence of f0=0 Hz, f1=, f
     s
    
    2
   
   ⁢
     
   Hz
  
  ,, and, f
   2
  
  =
  
   
    
     n
     *
     
      f
      s
     
    
    2
   
   ⁢
      
   Hz, are effective features;
ii) segmenting the sequence of, f
    s
   
   2
  
  ⁢
     
  Hz, amplitudes in the frequency domain; when the amplitude of the frequency light signal is greater than the threshold, a gesture is detected, then the feature sequence needs to be processed and gesture recognition is performed; otherwise, the feature sequence is skipped and gesture recognition is not required; and
iii) after selecting the feature sequence, K-nearest neighbor classification method is used to classify and realize gesture recognition, specifically: choose the amplitude sequence E0(t) corresponding to f0=0 Hz, the amplitude sequence E1(t) corresponding to, f
    1
   
   =
   
    
     
      f
      s
     
     2
    
    ⁢
      
    Hz
   
  
  ,, the product of the first derivative E0(t)′*E1(t)′, and the ratio of E1 to E2(t)(E2(t) is the amplitude sequence of, 3
      *
      
       f
       s
      
     
     2
    
    ⁢
      
    Hz
   
   )
  
  ,
     
  
   
    
     E
     1
    
    (
    t
    )
   
   
    
     E
     2
    
    (
    t
    )
   
  
  ,, as four key feature sequences, whereing each feature sequence is normalized using a zero-mean method, and dynamic time-warped is used to measure the distance.