def getWindow(imageFile,x,y,winsize,site):
"""
Extracts portion of raster defined by window as an array.
"""
inProj = osr.SpatialReference()
inProj.ImportFromEPSG(int('4326'))
outProj = osr.SpatialReference()
outProj.ImportFromEPSG(int('2835%s' % qvf.utmzone(imageFile)[-1]))
transform = osr.CoordinateTransformation(inProj, outProj)
(x, y, z) = transform.TransformPoint(x, y)
x = float(x)
y = float(y)
winsize = int(cmdargs.winsize)
imgInfo = gdalcommon.info(imageFile)
trans = imgInfo.transform
bands = imgInfo.rasterCount
(row,col) = gdalcommon.eastNorth2rowCol(trans,x,y)
(row,col) = (int(row), int(col))
temp = '%s_%s_%spix.tif' % (imageFile.split('.')[0],site.strip(),winsize)
cmd = 'gdal_translate -srcwin %s %s %s %s %s %s' % (col-int(.5*winsize), row-int(.5*winsize), winsize, winsize, imageFile, temp)
os.system(cmd)
return temp
def getStatVal(imageFile,longitude,latitude,winsize,statistic,site):
"""
Caculates the statistics on the pixels in the window array
"""
band1,band2,band3,band4,band5,band6,count = 'None','None','None','None','None','None','None'
if imageFile != 'None' and imageFile != None:
imageFile=qvf.changestage(imageFile,'tmp')
temp = '%s_%s_%spix.tif' % (imageFile.split('.')[0],site.strip(),winsize)
if not os.path.exists(temp):
subsetRaster = getWindow(imageFile,longitude,latitude,winsize,site)
else:
subsetRaster = temp
try:
imgInfo = gdalcommon.info(subsetRaster)
handle = gdal.Open(subsetRaster)
for band in [1,2,3,4,5,6]:
if handle != None:
bandHandle = handle.GetRasterBand(band)
bandArray = bandHandle.ReadAsArray()
maskedBand = ma.masked_values(bandArray, 0)
count = ma.count(maskedBand)
if statistic == 'mean': statVal = maskedBand.mean()
elif statistic == 'std': statVal = maskedBand.std()
else:
statVal = None
if band == 1:
band1 = statVal
elif band == 2:
band2 = statVal
elif band == 3:
band3 = statVal
elif band == 4:
band4 = statVal
elif band == 5:
band5 = statVal
elif band == 6:
band6 = statVal
except:
pass
return band1, band2, band3, band4, band5, band6, count
