Merge pull request #1129 from etiennesky/gdaltools_fixes2

gdaltools: use GDAL python bindings to get raster SRS and extent (fix #9460)
qgis · Feb 5, 2014 · 58faa5b · 58faa5b
2 parents 6178860 + 4b9e181
commit 58faa5b
Showing 1 changed file with 33 additions and 47 deletions.
diff --git a/python/plugins/GdalTools/tools/GdalTools_utils.py b/python/plugins/GdalTools/tools/GdalTools_utils.py
@@ -35,7 +35,7 @@
 from qgis.core import *
 from qgis.gui import *
 
-from osgeo import gdal, ogr
+from osgeo import gdal, ogr, osr
 from osgeo.gdalconst import *
 
 import os
@@ -287,59 +287,45 @@ def getVectorFields(vectorFile):
 
 # get raster SRS if possible
 def getRasterSRS( parent, fileName ):
-    processSRS = QProcess( parent )
-    if ( GdalConfig.versionNum() >= 1900 ):
-        processSRS.start( "gdalsrsinfo", ["-o", "wkt", "-p", fileName], QIODevice.ReadOnly )
-    else:
-        processSRS.start( "gdalinfo", [fileName], QIODevice.ReadOnly )
-    arr = ''
-    if processSRS.waitForFinished():
-      arr = str(processSRS.readAllStandardOutput())
-      processSRS.close()
-
-    if arr == '':
-      return ''
+    ds = gdal.Open(fileName)
+    if ds is None:
+        return ''
 
-    info = arr.splitlines()
-    if len(info) == 0:
+    proj = ds.GetProjectionRef()
+    if proj is None:
       return ''
+
+    sr = osr.SpatialReference()
+    if sr.ImportFromWkt(proj) != gdal.CE_None:
+        return ''
 
-    for elem in reversed(info):
-        m = re.match("^\s*AUTHORITY\[\"([a-z]*[A-Z]*)\",\"(\d*)\"\]", elem)
-        if m and len(m.groups()) == 2:
-            return '%s:%s' % (m.group(1), m.group(2))
+    name = sr.GetAuthorityName(None)
+    code = sr.GetAuthorityCode(None)
+    if name is not None and code is not None:
+        return '%s:%s' % (name,code)
 
     return ''
 
+# get raster extent using python API - replaces old method which parsed gdalinfo output
 def getRasterExtent(parent, fileName):
-    processSRS = QProcess( parent )
-    processSRS.start( "gdalinfo", [fileName], QIODevice.ReadOnly )
-    arr = ''
-    if processSRS.waitForFinished():
-      arr = str(processSRS.readAllStandardOutput())
-      processSRS.close()
-
-    if arr == '':
-      return
-
-    ulCoord = lrCoord = ''
-    xUL = yLR = xLR = yUL = 0
-    info = arr.splitlines()
-    for elem in info:
-        m = re.match("^Upper\sLeft.*", elem)
-        if m:
-            ulCoord = m.group(0).strip()
-            ulCoord = ulCoord[string.find(ulCoord,"(") + 1 : string.find(ulCoord,")") - 1].split( "," )
-            xUL = float(ulCoord[0])
-            yUL = float(ulCoord[1])
-            continue
-        m = re.match("^Lower\sRight.*", elem)
-        if m:
-            lrCoord = m.group(0).strip()
-            lrCoord = lrCoord[string.find(lrCoord,"(") + 1 : string.find(lrCoord,")") - 1].split( "," )
-            xLR = float(lrCoord[0])
-            yLR = float(lrCoord[1])
-            continue
+    ds = gdal.Open(fileName)
+    if ds is None:
+        return
+
+    x = ds.RasterXSize
+    y = ds.RasterYSize
+
+    gt = ds.GetGeoTransform()
+    if gt is None:
+        xUL = 0
+        yUL = 0
+        xLR = x
+        yLR = y
+    else:
+        xUL = gt[0]
+        yUL = gt[3]
+        xLR = gt[0] + gt[1]*x + gt[2]*y
+        yLR = gt[3] + gt[4]*x + gt[5]*y
 
     return QgsRectangle( xUL, yLR, xLR, yUL )