Diff for "\AG1_Freibord"

Differences between revisions 2 and 14 (spanning 12 versions)

Die Besprechung ueber das Vorgehen ihrer Aufgaben ergab:

die Transformation in polarstereographische Koordinaten und der nachfolgende Uebergang zu den Bildpunkten von ASAR
Eckpunkten und Aufloseung des ASAR-Bildes variieren frei -> allgemeingueltiges Programm fuer den Uebergang des Outputs erfolgt als Vektor in der Form x, y, Freiboardhoehe(fbh)

fbh_bildkoordinaten.py

   1 from polar_projection import *
   2 from read_asar import *
   3 from read_icesat import *
   4 from coord_transform import *
   5 from scipy 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     A=coord_transformation(ASAR_p)
  20 
  21     # reading freeboard data and computing geographic into polarstereographic coordinates
  22     ICESAT_p,fbh=read_icesat(filename2,sgn)    #fbh are measured freeboard heights in cm
  23 
  24     # calculating new coordinates for freeboard data
  25     x_neu=[]
  26     y_neu=[]
  27     for x,y in zip(ICESAT_p[0],ICESAT_p[1]):
  28         x_neu.append(dot(array([A[0,0],A[0,1]]),array([x,y]))+A[0,2])
  29         y_neu.append(dot(array([A[1,0],A[1,1]]),array([x,y]))+A[1,2])
  30    
  31     # cutting off non-corresponding data values  
  32     m=-1
  33     index_vec=[]
  34     for xn,yn in zip(x_neu,y_neu):
  35         m=m+1
  36         if xn<=1. and xn >=0. and yn<=1. and yn >=0.:
  37             index_vec.append(m)
  38 
  39     x_bild=[]
  40     y_bild=[] 
  41     fbh_bild=[]
  42     for i in index_vec:
  43         x_bild.append(x_neu[i])
  44         y_bild.append(y_neu[i])
  45         fbh_bild.append(fbh[i])
  46 
  47     x_y_fbh=array([x_bild,y_bild,fbh_bild])
  48 
  49     return x_y_fbh

coord_transform.py

   1 from Numeric import *
   2 import LinearAlgebra as la
   3 
   4 def coord_transformation(ASAR_p):
   5     # polarstereographic coordinate system
   6     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])
   7     # new coordinate system with normalized coordinates  
   8     y10,x10,y11,x11,y12,x12,y13,x13=0,0,1,0,1,1,0,1
   9 
  10     # calculating transformation matrix:
  11     P0=array([[x00, x01, x02, x03],[y00,y01,y02,y03],[1.0,1.0,1.0,1.0]])
  12     P1=array([[x10, x11, x12, x13],[y10,y11,y12,y13],[1.0,1.0,1.0,1.0]])
  13 
  14     Faktor1=dot(P1,transpose(P0))
  15     Faktor2=la.inverse(dot(P0,transpose(P0)))
  16     A=dot(Faktor1,Faktor2)  # Transformation matrix
  17     return A

read_icesat.py

   1 import string
   2 from polar_projection 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

Zum Testen hängt man an das obige Programm folgende Zeilen an:

   1 filename1='ASA_IMP_1PNDPA20060617_043346_000000162048_00362_22460_2136.N1'
   2 filename2='LonLatFre_1706_6.xyz'
   3 ergebnis=fit_freeboard_ASAR(filename1,filename2)

-  ⇤ ← Revision 2 as of 2008-07-09 09:17:16 → 
  Size: 3008
  Editor: NinaMaass
  Comment:
+   ← Revision 14 as of 2008-07-11 09:08:12 → ⇥
  Size: 3681
  Editor: NinaMaass
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 4:
-  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
+  Eckpunkten und Aufloseung des ASAR-Bildes variieren frei -> allgemeingueltiges Programm fuer den Uebergang
  des Outputs erfolgt als Vektor in der Form x, y, Freiboardhoehe(fbh)
 Line 9:
-fbh_bildkoordinaten.py
+'''fbh_bildkoordinaten.py'''
 Line 12:
-from geo_polar import *
+from polar_projection import *
 Line 14:
-import string
+from read_icesat import *
from coord_transform import *
from scipy import *
-Line 16:
+Line 18:
-def fit_freeboard_ASAR(filename1,filename2,resolution):
    """filename1: ASAR data file, filename2: freeboard data file, resolution: data resolution"""
+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)]"""
-Line 20:
+Line 25:
-    lat1,lon1,lat2,lon2,lat3,lon3,lat4,lon4=read_asar_corners(filename1)
    
    ASAR_1=[lat1,lon1]      
    ASAR_2=[lat2,lon2]      
    ASAR_3=[lat3,lon3]      
    ASAR_4=[lat4,lon4]
+    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)
-Line 27:
+Line 30:
-    ASAR_1p=mapll(ASAR_1[0],ASAR_1[1],sgn)  #computing polarstereographic coordinates
    ASAR_2p=mapll(ASAR_2[0],ASAR_2[1],sgn)
    ASAR_3p=mapll(ASAR_3[0],ASAR_3[1],sgn)
    ASAR_4p=mapll(ASAR_4[0],ASAR_4[1],sgn)
+    A=coord_transformation(ASAR_p)
 Line 32:
-    X=int(abs(ASAR_2p[0]-ASAR_1p[0])/resolution)  #image size in pixel
    Y=int(abs(ASAR_4p[1]-ASAR_1p[1])/resolution)

    # polarstereographic coordinate system
    y00,x00,y01,x01,y02,x02,y03,x03=int(ASAR_1p[1]),int(ASAR_1p[0]),int(ASAR_4p[1]),int(ASAR_4p[0]),int(ASAR_3p[1]),int(ASAR_3p[0]),int(ASAR_2p[1]),int(ASAR_2p[0])
    # 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
    lon=[]
    lat=[]
    fbh=[]
    datei = open (filename2, 'r')
    line=datei.readline()
    k=-1
    while line!="":
        k=k+1
        data=string.split(line)
        lon.append(float(data[0]))
        lat.append(abs(float(data[1])))
        fbh.append(float(data[2]))
        line=datei.readline()

    polar=mapll(array(lat),array(lon),sgn)
+    # reading freeboard data and computing geographic into polarstereographic coordinates
    ICESAT_p,fbh=read_icesat(filename2,sgn)    #fbh are measured freeboard heights in cm
-Line 68:
+Line 38:
-    for x,y in zip(polar[0],polar[1]):
+    for x,y in zip(ICESAT_p[0],ICESAT_p[1]):
-Line 71:
+Line 41:
     # cutting off non-corresponding data values
-Line 90:
+Line 60:
-    return x_y_fbh
+    return x_y_fbh
}}}
-Line 92:
+Line 63:
+'''coord_transform.py'''
{{{#!python
from Numeric import *
import LinearAlgebra as la

def coord_transformation(ASAR_p):
    # 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=la.inverse(dot(P0,transpose(P0)))
    A=dot(Faktor1,Faktor2)  # Transformation matrix
    return A
-Line 93:
+Line 83:
+'''read_icesat.py'''


{{{#!python
import string
from polar_projection 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'''

Zum Testen hängt man an das obige Programm folgende Zeilen an: 
{{{#!python
filename1='ASA_IMP_1PNDPA20060617_043346_000000162048_00362_22460_2136.N1'
filename2='LonLatFre_1706_6.xyz'
ergebnis=fit_freeboard_ASAR(filename1,filename2)
}}}

{{attachment:schemabild.jpg}}

{{attachment.schemabild2.jpg}}