1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
|
#! /usr/bin/env python
#
#
# This is a simple script based on GDAL and used to retrieve value of single raster pixel.
# It is used in WKTRaster testing to compare raster samples.
#
# Copyright (C) 2009 Mateusz Loskot <mateusz@loskot.net>
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software Foundation,
# Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
from __future__ import print_function
from osgeo import gdal
from osgeo import osr
import osgeo.gdalconst as gdalc
import struct
import sys
def pt2fmt(pt):
fmttypes = {
gdalc.GDT_Byte: 'B',
gdalc.GDT_Int16: 'h',
gdalc.GDT_UInt16: 'H',
gdalc.GDT_Int32: 'i',
gdalc.GDT_UInt32: 'I',
gdalc.GDT_Float32: 'f',
gdalc.GDT_Float64: 'f'
}
return fmttypes.get(pt, 'x')
if len(sys.argv) < 5 or len(sys.argv) > 6:
print("Usage: pixval.py <raster> <band> <x> <y>")
print("\traster - GDAL supported dataset")
print("\tband - 1-based number of band")
print("\toverview - optional 1-based number of overview")
print("\tx - Pixel column - 1..N where N is raster X dimension")
print("\ty - Pixel row - 1..N where N is raster Y dimension")
sys.exit(0)
infile = sys.argv[1]
nband = int(sys.argv[2])
x = int(sys.argv[3])
y = int(sys.argv[4])
if len(sys.argv) > 5:
noverview = int(sys.argv[5])
else:
noverview = None
print("File : %s" % infile)
print("Band : %d" % nband)
if noverview is not None:
print("Overview: %d" % noverview)
print("Pixel: %d x %d" % (x, y))
ds = gdal.Open(infile, gdalc.GA_ReadOnly);
if ds is None:
sys.exit('ERROR: Cannot open input file: ' + str(infile))
band = ds.GetRasterBand(nband)
if band is None:
sys.exit('Cannot access band %d', nband)
if noverview is None:
src_band = band
else:
if noverview > 0 and noverview <= band.GetOverviewCount():
src_band = band.GetOverview(noverview - 1)
else:
print("ERROR: Invalid overview index")
print("Band %d consists of %d overivews" % (nband, band.GetOverviewCount()))
sys.exit(1)
if x <= 0 or x > src_band.XSize or y <= 0 or y > src_band.YSize:
print("ERROR: Invalid pixel coordinates")
print("Band or overview dimensions are %d x %d" % (src_band.XSize, src_band.YSize))
sys.exit(1)
# Pixel index is 0-based
pixel = src_band.ReadRaster(x - 1, y - 1, 1, 1, 1, 1)
fmt = pt2fmt(src_band.DataType)
pixval = struct.unpack(fmt, pixel)
print("Pixel value -> %s" % str(pixval[0]))
|
