70 lines
1.8 KiB
Python
70 lines
1.8 KiB
Python
from ctypes import byref, c_int
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from django.contrib.gis.gdal.base import GDALBase
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from django.contrib.gis.gdal.prototypes import raster as capi
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from django.utils.encoding import force_text
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from .const import GDAL_PIXEL_TYPES
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class GDALBand(GDALBase):
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"""
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Wraps a GDAL raster band, needs to be obtained from a GDALRaster object.
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"""
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def __init__(self, source, index):
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self.source = source
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self.ptr = capi.get_ds_raster_band(source.ptr, index)
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@property
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def description(self):
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"""
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Returns the description string of the band.
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"""
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return force_text(capi.get_band_description(self.ptr))
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@property
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def width(self):
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"""
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Width (X axis) in pixels of the band.
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"""
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return capi.get_band_xsize(self.ptr)
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@property
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def height(self):
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"""
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Height (Y axis) in pixels of the band.
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"""
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return capi.get_band_ysize(self.ptr)
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def datatype(self, as_string=False):
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"""
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Returns the GDAL Pixel Datatype for this band.
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"""
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dtype = capi.get_band_datatype(self.ptr)
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if as_string:
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dtype = GDAL_PIXEL_TYPES[dtype]
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return dtype
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@property
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def min(self):
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"""
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Returns the minimum pixel value for this band.
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"""
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return capi.get_band_minimum(self.ptr, byref(c_int()))
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@property
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def max(self):
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"""
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Returns the maximum pixel value for this band.
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"""
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return capi.get_band_maximum(self.ptr, byref(c_int()))
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@property
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def nodata_value(self):
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"""
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Returns the nodata value for this band, or None if it isn't set.
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"""
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nodata_exists = c_int()
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value = capi.get_band_nodata_value(self.ptr, nodata_exists)
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return value if nodata_exists else None
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