DETECT (Feb93)                    model                   DETECT (Feb93)



NAME
    detect
    
    
USAGE
    detect lsndb lsgain lsdark nphase lsiiii cyfrac mbytes
    
    
PARAMETERS
    
    lsndb
        List of input image names: numerator, denominator, brightness.
        The 3rd pixel dimension must be 3.
    
    lsgain
        List of input image names: gain.
        The 3rd pixel dimension must be 1.
        Optional input parameter.
    
    lsdark
        List of input image names containing the dark current.
        The 3rd pixel dimension must be 1.
        Optional input parameter.
    
    nphase
        3rd dimension of the output images which is also the  number  of
        intensity phases.
    
    lsiiii
        List of Output Image Names: Intensities.
        The 3rd dimension is set by the value of NPHASE.
    
    cyfrac
        Camera readout cycle fraction.
    
    mbytes
        Available memory for image pixel arrays in Megabytes.
        This  parameter  can  be  used  to control the amount of virtual
        memory paging that will occur if all the  pixel  arrays  do  not
        fit into the available real memory.
    
    
IMAGE HEADER WORDS
    
    The  three  image  dimension  parameters  are  read  from  the image
    headers for input images: LSNDB, LSGAIN, LSDARK.
    
    The header for the output image, LSIIII, is copied from  the  header
    for the input image, LSNDB.
    
    The following output image dimension parameters are reset:
        IM_LEN(.,3) is determined from the input parameter, NPHASE.
    
    The  task  writes  processing  history  information  into the output
    header using 'gr_history' from 'grutil/'.
    
    
DESCRIPTION
    
    DETECT  computes  the  effects  of  the  detector  in  the   Fourier 
    tachometer.
    
    DETECT  is  from  Tim  Brown's  Fourier  tachometer  modeling  code, 
    "FAKEFT".
    
    The phase intensity values for phase angle, I3,
        (I3=1,N3; N3=NPHASE, an input parameter)
    in pixel row, I2,
        (I2=1,N2; N2=IM_LEN(,.2), the size of the 2nd dim. of LSIIII)
    in pixel, I1,
        (I1=1,N1; N1=IM_LEN(,.1), the size of the 1nd dim. of LSIIII)
    are
        DARK_CURRENT(I1,I2)
        +(1.0+GAIN(I1,I2))*BRIGHTNESS(I1,I2)
        *(1.0+NUMERATOR(I1,I2)*SPHA+DENOMINATOR(I1,I2)*CPHA)
    where
        SPHA = SIN(CAMERA_READOUT_PHASE + FTACH_PHASE)
        CPHA = COS(CAMERA_READOUT_PHASE + FTACH_PHASE)
        CAMERA_READOUT_PHASE=2*PI*CYFRAC*FLOAT(I2-1)/FLOAT(N2)
        FTACH_PHASE=         2*PI*       FLOAT(I3-1)/FLOAT(N3)
        NUMERATOR   is the 1st 2d pixel array in LSNDB
        DENOMINATOR is the 2nd 2d pixel array in LSNDB
        BRIGHTNESS  is the 3rd 2d pixel array in LSNDB
    
    
EXAMPLES
    
    
TIME REQUIREMENTS
    
    
BUGS
    
    
SEE ALSO
    genvim
    interf
    synftach