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'''fbh_bildkoordinaten.py'''

{{{#!python
from polar_projection import *
from read_asar import *
from read_icesat import *
from LinearAlgebra import *
from Numeric import *

def fit_freeboard_ASAR(filename1,filename2):
    """filename1: ASAR data file, filename2: freeboard data file
       creates new coordinate system defined by corners of ASAR image and selects freeboard values within ASAR image box
       returns an array containing normalized image coordinates and corresponding freeboard values:
       [x_coordinate, y_coordinate, freeboardheight(cm)]"""
    
    sgn=-1 #Antarctica
    ASAR=array(read_asar_corners(filename1))
    ASAR_p=zeros(8)
    for k in arange(0,7,2): #computing polarstereographic coordinates
        ASAR_p[k:k+2]=mapll(ASAR[k],ASAR[k+1],sgn)
   
    # polarstereographic coordinate system
    y00,x00,y01,x01,y02,x02,y03,x03=int(ASAR_p[1]),int(ASAR_p[0]),int(ASAR_p[7]),int(ASAR_p[6]),int(ASAR_p[5]),int(ASAR_p[4]),int(ASAR_p[3]),int(ASAR_p[2])
    # new coordinate system with normalized coordinates
    y10,x10,y11,x11,y12,x12,y13,x13=0,0,1,0,1,1,0,1

    # calculating transformation matrix:
    P0=array([[x00, x01, x02, x03],[y00,y01,y02,y03],[1.0,1.0,1.0,1.0]])
    P1=array([[x10, x11, x12, x13],[y10,y11,y12,y13],[1.0,1.0,1.0,1.0]])

    Faktor1=dot(P1,transpose(P0))
    Faktor2=inverse(dot(P0,transpose(P0)))
    A=dot(Faktor1,Faktor2) # Transformation matrix

    # reading freeboard data and computing geographic into polarstereographic coordinates
    ICESAT_p,fbh=read_icesat(filename2,sgn)

    # calculating new coordinates for freeboard data
    x_neu=[]
    y_neu=[]
    for x,y in zip(ICESAT_p[0],ICESAT_p[1]):
        x_neu.append(dot(array([A[0,0],A[0,1]]),array([x,y]))+A[0,2])
        y_neu.append(dot(array([A[1,0],A[1,1]]),array([x,y]))+A[1,2])

    # cutting off non-corresponding data values
    m=-1
    index_vec=[]
    for xn,yn in zip(x_neu,y_neu):
        m=m+1
        if xn<=1. and xn >=0. and yn<=1. and yn >=0.:
            index_vec.append(m)

    x_bild=[]
    y_bild=[]
    fbh_bild=[]
    for i in index_vec:
        x_bild.append(x_neu[i])
        y_bild.append(y_neu[i])
        fbh_bild.append(fbh[i])

    x_y_fbh=array([x_bild,y_bild,fbh_bild])

    return x_y_fbh
}}}

{{{#!python
import string
from geo_polar import *
from scipy import io

def read_icesat(filename,sgn):
    data=io.read_array(filename)
    polar=mapll(data[:,1],data[:,0],sgn)
    fbh=data[:,2]
    return polar,fbh
}}}

Die benötigten Module polar_projection.py und read_asar.py sind auf der Seite der Arbeitsgruppe 0 [[AG0_ASAR_Einlesen]] zu finden.

'''fbh_bildkoordinaten_test.py'''

{{{#!python
from polar_projection import *
from read_asar import *
from read_icesat import *
from LinearAlgebra import *
from Numeric import *

def fit_freeboard_ASAR(filename1,filename2):
    """filename1: ASAR data file, filename2: freeboard data file
       creates new coordinate system defined by corners of ASAR image and selects freeboard values within ASAR image box
       returns an array containing normalized image coordinates and corresponding freeboard values:
       [x_coordinate, y_coordinate, freeboardheight(cm)]"""
    
    sgn=-1 #Antarctica
    ASAR=array(read_asar_corners(filename1))
    ASAR_p=zeros(8)
    for k in arange(0,7,2): #computing polarstereographic coordinates
        ASAR_p[k:k+2]=mapll(ASAR[k],ASAR[k+1],sgn)
   
    # polarstereographic coordinate system
    y00,x00,y01,x01,y02,x02,y03,x03=int(ASAR_p[1]),int(ASAR_p[0]),int(ASAR_p[7]),int(ASAR_p[6]),int(ASAR_p[5]),int(ASAR_p[4]),int(ASAR_p[3]),int(ASAR_p[2])
    # new coordinate system with normalized coordinates
    y10,x10,y11,x11,y12,x12,y13,x13=0,0,1,0,1,1,0,1

    # calculating transformation matrix:
    P0=array([[x00, x01, x02, x03],[y00,y01,y02,y03],[1.0,1.0,1.0,1.0]])
    P1=array([[x10, x11, x12, x13],[y10,y11,y12,y13],[1.0,1.0,1.0,1.0]])

    Faktor1=dot(P1,transpose(P0))
    Faktor2=inverse(dot(P0,transpose(P0)))
    A=dot(Faktor1,Faktor2) # Transformation matrix

    # reading freeboard data and computing geographic into polarstereographic coordinates
    ICESAT_p,fbh=read_icesat(filename2,sgn)

    # calculating new coordinates for freeboard data
    x_neu=[]
    y_neu=[]
    for x,y in zip(ICESAT_p[0],ICESAT_p[1]):
        x_neu.append(dot(array([A[0,0],A[0,1]]),array([x,y]))+A[0,2])
        y_neu.append(dot(array([A[1,0],A[1,1]]),array([x,y]))+A[1,2])

    # cutting off non-corresponding data values
    m=-1
    index_vec=[]
    for xn,yn in zip(x_neu,y_neu):
        m=m+1
        if xn<=1. and xn >=0. and yn<=1. and yn >=0.:
            index_vec.append(m)

    x_bild=[]
    y_bild=[]
    fbh_bild=[]
    for i in index_vec:
        x_bild.append(x_neu[i])
        y_bild.append(y_neu[i])
        fbh_bild.append(fbh[i])

    x_y_fbh=array([x_bild,y_bild,fbh_bild])

    return x_y_fbh

filename1='ASA_IMP_1PNDPA20060617_043346_000000162048_00362_22460_2136.N1'
filename2='LonLatFre_1706_6.xyz'
ergebnis=fit_freeboard_ASAR(filename1,filename2)
}}}

{{attachment:schemabild.jpg}}

Die Besprechung ueber das Vorgehen ihrer Aufgaben ergab:

  • die Transformation in polarstereographische Koordinaten und der nachfolgende Uebergang zu den Bildpunkten von ASAR

    Eckpunkte und Aufloseung des ASAR-Bildes variieren frei -> allgemeingueltiges Programm fuer den Uebergang der Output erfolgt als Vektor in der Form x, y, Freiboardhoehe; eventuell die Floatangabe

fbh_bildkoordinaten.py

   1 from polar_projection import *
   2 from read_asar import *
   3 from read_icesat import *
   4 from LinearAlgebra import *
   5 from Numeric import *
   6 
   7 def fit_freeboard_ASAR(filename1,filename2):
   8     """filename1: ASAR data file, filename2: freeboard data file
   9        creates new coordinate system defined by corners of ASAR image and selects freeboard values within ASAR image box
  10        returns an array containing normalized image coordinates and corresponding freeboard values:
  11        [x_coordinate, y_coordinate, freeboardheight(cm)]"""
  12     
  13     sgn=-1  #Antarctica
  14     ASAR=array(read_asar_corners(filename1))
  15     ASAR_p=zeros(8)
  16     for k in arange(0,7,2):       #computing polarstereographic coordinates
  17         ASAR_p[k:k+2]=mapll(ASAR[k],ASAR[k+1],sgn)
  18    
  19     # polarstereographic coordinate system
  20     y00,x00,y01,x01,y02,x02,y03,x03=int(ASAR_p[1]),int(ASAR_p[0]),int(ASAR_p[7]),int(ASAR_p[6]),int(ASAR_p[5]),int(ASAR_p[4]),int(ASAR_p[3]),int(ASAR_p[2])
  21     # new coordinate system with normalized coordinates  
  22     y10,x10,y11,x11,y12,x12,y13,x13=0,0,1,0,1,1,0,1
  23 
  24     # calculating transformation matrix:
  25     P0=array([[x00, x01, x02, x03],[y00,y01,y02,y03],[1.0,1.0,1.0,1.0]])
  26     P1=array([[x10, x11, x12, x13],[y10,y11,y12,y13],[1.0,1.0,1.0,1.0]])
  27 
  28     Faktor1=dot(P1,transpose(P0))
  29     Faktor2=inverse(dot(P0,transpose(P0)))
  30     A=dot(Faktor1,Faktor2)  # Transformation matrix 
  31 
  32     # reading freeboard data and computing geographic into polarstereographic coordinates
  33     ICESAT_p,fbh=read_icesat(filename2,sgn)
  34 
  35     # calculating new coordinates for freeboard data
  36     x_neu=[]
  37     y_neu=[]
  38     for x,y in zip(ICESAT_p[0],ICESAT_p[1]):
  39         x_neu.append(dot(array([A[0,0],A[0,1]]),array([x,y]))+A[0,2])
  40         y_neu.append(dot(array([A[1,0],A[1,1]]),array([x,y]))+A[1,2])
  41 
  42     # cutting off non-corresponding data values  
  43     m=-1
  44     index_vec=[]
  45     for xn,yn in zip(x_neu,y_neu):
  46         m=m+1
  47         if xn<=1. and xn >=0. and yn<=1. and yn >=0.:
  48             index_vec.append(m)
  49 
  50     x_bild=[]
  51     y_bild=[] 
  52     fbh_bild=[]
  53     for i in index_vec:
  54         x_bild.append(x_neu[i])
  55         y_bild.append(y_neu[i])
  56         fbh_bild.append(fbh[i])
  57 
  58     x_y_fbh=array([x_bild,y_bild,fbh_bild])
  59 
  60     return x_y_fbh 

   1 import string
   2 from geo_polar import *
   3 from scipy import io
   4 
   5 def read_icesat(filename,sgn):
   6     data=io.read_array(filename)
   7     polar=mapll(data[:,1],data[:,0],sgn)
   8     fbh=data[:,2]
   9     return polar,fbh

Die benötigten Module polar_projection.py und read_asar.py sind auf der Seite der Arbeitsgruppe 0 AG0_ASAR_Einlesen zu finden.

fbh_bildkoordinaten_test.py

   1 from polar_projection import *
   2 from read_asar import *
   3 from read_icesat import *
   4 from LinearAlgebra import *
   5 from Numeric import *
   6 
   7 def fit_freeboard_ASAR(filename1,filename2):
   8     """filename1: ASAR data file, filename2: freeboard data file
   9        creates new coordinate system defined by corners of ASAR image and selects freeboard values within ASAR image box
  10        returns an array containing normalized image coordinates and corresponding freeboard values:
  11        [x_coordinate, y_coordinate, freeboardheight(cm)]"""
  12     
  13     sgn=-1  #Antarctica
  14     ASAR=array(read_asar_corners(filename1))
  15     ASAR_p=zeros(8)
  16     for k in arange(0,7,2):       #computing polarstereographic coordinates
  17         ASAR_p[k:k+2]=mapll(ASAR[k],ASAR[k+1],sgn)
  18    
  19     # polarstereographic coordinate system
  20     y00,x00,y01,x01,y02,x02,y03,x03=int(ASAR_p[1]),int(ASAR_p[0]),int(ASAR_p[7]),int(ASAR_p[6]),int(ASAR_p[5]),int(ASAR_p[4]),int(ASAR_p[3]),int(ASAR_p[2])
  21     # new coordinate system with normalized coordinates  
  22     y10,x10,y11,x11,y12,x12,y13,x13=0,0,1,0,1,1,0,1
  23 
  24     # calculating transformation matrix:
  25     P0=array([[x00, x01, x02, x03],[y00,y01,y02,y03],[1.0,1.0,1.0,1.0]])
  26     P1=array([[x10, x11, x12, x13],[y10,y11,y12,y13],[1.0,1.0,1.0,1.0]])
  27 
  28     Faktor1=dot(P1,transpose(P0))
  29     Faktor2=inverse(dot(P0,transpose(P0)))
  30     A=dot(Faktor1,Faktor2)  # Transformation matrix 
  31 
  32     # reading freeboard data and computing geographic into polarstereographic coordinates
  33     ICESAT_p,fbh=read_icesat(filename2,sgn)
  34 
  35     # calculating new coordinates for freeboard data
  36     x_neu=[]
  37     y_neu=[]
  38     for x,y in zip(ICESAT_p[0],ICESAT_p[1]):
  39         x_neu.append(dot(array([A[0,0],A[0,1]]),array([x,y]))+A[0,2])
  40         y_neu.append(dot(array([A[1,0],A[1,1]]),array([x,y]))+A[1,2])
  41 
  42     # cutting off non-corresponding data values  
  43     m=-1
  44     index_vec=[]
  45     for xn,yn in zip(x_neu,y_neu):
  46         m=m+1
  47         if xn<=1. and xn >=0. and yn<=1. and yn >=0.:
  48             index_vec.append(m)
  49 
  50     x_bild=[]
  51     y_bild=[] 
  52     fbh_bild=[]
  53     for i in index_vec:
  54         x_bild.append(x_neu[i])
  55         y_bild.append(y_neu[i])
  56         fbh_bild.append(fbh[i])
  57 
  58     x_y_fbh=array([x_bild,y_bild,fbh_bild])
  59 
  60     return x_y_fbh 
  61 
  62 filename1='ASA_IMP_1PNDPA20060617_043346_000000162048_00362_22460_2136.N1'
  63 filename2='LonLatFre_1706_6.xyz'
  64 ergebnis=fit_freeboard_ASAR(filename1,filename2)

schemabild.jpg

LehreWiki: \AG1_Freibord (last edited 2008-07-11 11:19:34 by NinaMaass)