Source code for gsdview.gdalbackend.gdalqt4
# -*- coding: utf-8 -*-
### Copyright (C) 2008-2012 Antonio Valentino <a_valentino@users.sf.net>
### This file is part of GSDView.
### GSDView 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.
### GSDView 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 GSDView; if not, write to the Free Software
### Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
'''Helper tools and custom components for binding GDAL and Qt4.'''
import logging
import numpy as np
from numpy import ma
from osgeo import gdal
from osgeo.gdal_array import GDALTypeCodeToNumericTypeCode
from qt import QtCore, QtGui
from .. import imgutils
from ..qt4support import numpy2qimage
from ..gdalbackend import gdalsupport
__author__ = 'Antonio Valentino <a_valentino@users.sf.net>'
__date__ = '$Date$'
__revision__ = '$Revision$'
[docs]def gdalcolorentry2qcolor(colrentry, interpretation=gdal.GPI_RGB):
qcolor = QtGui.QColor()
if interpretation == gdal.GPI_RGB:
qcolor.setRgb(colrentry.c1, colrentry.c2, colrentry.c3, colrentry.c4)
elif interpretation == gdal.GPI_Gray:
qcolor.setRgb(colrentry.c1, colrentry.c1, colrentry.c1)
elif interpretation == gdal.GPI_CMYK:
qcolor.setCmyk(colrentry.c1, colrentry.c2, colrentry.c3, colrentry.c4)
elif interpretation == gdal.GPI_HLS:
qcolor.setHsv(colrentry.c1, colrentry.c2, colrentry.c3)
#, colrentry.c4)
else:
raise ValueError('invalid color intepretatin: "%s"' % interpretation)
return qcolor
[docs]def safeDataStats(data, nodata=None):
if nodata is not None:
data = ma.masked_equal(data, nodata)
stats = (data.min(), data.max(), data.mean(), data.std())
stddev = stats[-1]
if ma.isMaskedArray(stddev) or stddev == 0:
stats = (None, None, None, None)
return stats
# @TODO: move GraphicsView here
[docs]class BaseGdalGraphicsItem(QtGui.QGraphicsItem):
Type = QtGui.QStandardItem.UserType + 1
def __init__(self, gdalobj, parent=None, scene=None, **kwargs):
super(BaseGdalGraphicsItem, self).__init__(parent, scene, **kwargs)
# @COMPATIBILITY: Qt >= 4.6.0 needs this flag to be set otherwise the
# exact exposedRect is not computed
# @SEEALSO: ItemUsesExtendedStyleOption item at
# http://doc.qt.nokia.com/4.6/qgraphicsitem.html#GraphicsItemFlag-enum
try:
self.setFlag(QtGui.QGraphicsItem.ItemUsesExtendedStyleOptions)
except AttributeError:
self.setFlag(QtGui.QGraphicsItem.GraphicsItemFlag(0x200))
self.gdalobj = gdalobj
try:
# dataset
w = gdalobj.RasterXSize
h = gdalobj.RasterYSize
except AttributeError:
# raster band
w = gdalobj.XSize
h = gdalobj.YSize
self._boundingRect = QtCore.QRectF(0, 0, w, h)
#self.read_threshold = 1600*1200
self.stretch = imgutils.LinearStretcher()
# @TODO: use lazy gaphicsitem inirialization
# @TODO: initilize stretching explicitly
self._stretch_initialized = False
def _clipRect(self, ovrband, rect, ovrlevel):
boundingRect = self._boundingRect
x = int((rect.x() - boundingRect.x()) // ovrlevel)
y = int((rect.y() - boundingRect.y()) // ovrlevel)
width = rect.width() // ovrlevel + 1 # @TODO: check
height = rect.height() // ovrlevel + 1 # @TODO: check
if x < 0:
x = 0
if y < 0:
y = 0
if (x + width) * ovrlevel > boundingRect.width():
width = ovrband.XSize - x
if (y + height) * ovrlevel > boundingRect.height():
height = ovrband.YSize - y
return x, y, width, height
def _targetRect(self, x, y, w, h, ovrlevel):
boundingRect = self._boundingRect
return QtCore.QRect(x * ovrlevel + boundingRect.x(),
y * ovrlevel + boundingRect.y(),
w * ovrlevel,
h * ovrlevel)
@staticmethod
def _levelOfDetailFromTransform(worldTransform):
# @COMPATIBILITY: since Qt v. 4.6.0 the levelOfDetail attribute of
# QStyleOptionGraphicsItem is deprecated
# @SEEALSO: ItemUsesExtendedStyleOption item at
# http://doc.qt.nokia.com/4.6/qgraphicsitem.html#GraphicsItemFlag-enum
#
# From qt/src/gui/styles/qstyleoption.cpp:5130
if worldTransform.type() <= QtGui.QTransform.TxTranslate:
return 1 # Translation only? The LOD is 1.
# Two unit vectors.
v1 = QtCore.QLineF(0, 0, 1, 0)
v2 = QtCore.QLineF(0, 0, 0, 1)
# LOD is the transformed area of a 1x1 rectangle.
return np.sqrt(worldTransform.map(v1).length() *
worldTransform.map(v2).length())
@staticmethod
def _levelOfDetail(option, painter):
# @COMPATIBILITY: since Qt v. 4.6.0 the levelOfDetail attribute of
# QStyleOptionGraphicsItem is deprecated
# @SEEALSO: ItemUsesExtendedStyleOption item at
# http://doc.qt.nokia.com/4.6/qgraphicsitem.html#GraphicsItemFlag-enum
if hasattr(option, 'levelOfDetailFromTransform'):
levelOfDetail = option.levelOfDetailFromTransform(
painter.transform())
elif QtCore.qVersion() >= '4.6.0':
levelOfDetail = BaseGdalGraphicsItem._levelOfDetailFromTransform(
painter.transform())
else:
levelOfDetail = option.levelOfDetail
return levelOfDetail
@staticmethod
def _bestOvrLevel(band, levelOfDetail):
ovrlevel = 1
ovrindex = None
if band.GetOverviewCount() > 0:
if levelOfDetail <= 0:
reqlevel = 1.
else:
reqlevel = 1. / levelOfDetail
try:
ovrindex = gdalsupport.ovrBestIndex(band, reqlevel)
except gdalsupport.MissingOvrError:
pass
else:
ovrlevel = gdalsupport.ovrLevels(band)[ovrindex]
if abs(reqlevel - 1) < abs(reqlevel - ovrlevel):
ovrlevel = 1
ovrindex = None
else:
band = band.GetOverview(ovrindex)
return band, ovrlevel, ovrindex
@staticmethod
def _defaultStretch(band, data=None, nsigma=5):
# @NOTE: statistics computation is potentially slow so first check
# if fast statistics retriewing is possible
stats = (None, None, None, None)
if band and gdalsupport.hasFastStats(band):
stats = gdalsupport.SafeGetStatistics(band, True, True)
if None in stats and data is not None and data.size <= 4 * 1024 ** 2:
stats = safeDataStats(data, band.GetNoDataValue())
if None in stats:
if band and band.DataType == gdal.GDT_Byte:
return 0, 255
else:
return None, None
vmin, vmax, mean, stddev = stats
lower = max(mean - nsigma * stddev, 0)
upper = min(mean + nsigma * stddev, vmax)
return lower, upper
[docs] def setDefaultStretch(self, data=None):
lower, upper = self._defaultStretch(self.gdalobj, data)
if None in (lower, upper) or (lower == upper):
self._stretch_initialized = False
return
self.stretch.set_range(lower, upper)
self._stretch_initialized = True
@staticmethod
def _dataRange(band, data=None):
if band and gdalsupport.hasFastStats(band):
vmin, vmax, mean, stddev = gdalsupport.SafeGetStatistics(band,
True)
if None not in (vmin, vmax, mean, stddev):
if gdal.DataTypeIsComplex(band.DataType):
vmin, vmax = 0, vmax * np.sqrt(2)
return vmin, vmax
if data is not None and data.size <= 4 * 1024 ** 2:
vmin, vmax, mean, stddev = safeDataStats(band)
if None not in (vmin, vmax, mean, stddev):
return data.min(), data.max()
if band:
tmap = {
gdal.GDT_Byte: (0, 255),
gdal.GDT_UInt16: (0, 2 ** 16 - 1),
gdal.GDT_UInt32: (0, 2 ** 32 - 1),
gdal.GDT_Int16: (-2 ** 15, 2 ** 15 - 1),
gdal.GDT_Int32: (-2 ** 31, 2 ** 31 - 1),
gdal.GDT_CInt16: (0, 2 ** 15 * np.sqrt(2)),
gdal.GDT_CInt32: (0, 2 ** 31 * np.sqrt(2)),
gdal.GDT_CFloat32: (0, None),
gdal.GDT_CFloat64: (0, None),
}
return tmap.get(band.DataType, (None, None))
return None, None
[docs]class UIntGdalGraphicsItem(BaseGdalGraphicsItem):
'''GDAL graphics item specialized for 8 and 16 it unsigned integers.
Uses an unchecked LUT for transformations.
'''
Type = BaseGdalGraphicsItem.Type + 1
def __init__(self, band, parent=None, scene=None, **kwargs):
super(UIntGdalGraphicsItem, self).__init__(band, parent, scene,
**kwargs)
# @TODO: maybe it is batter to use a custo mexception: ItemTypeError
if band.DataType not in (gdal.GDT_Byte, gdal.GDT_UInt16):
typename = gdal.GetDataTypeName(band.DataType)
raise ValueError('invalid data type: "%s"' % typename)
dtype = np.dtype(GDALTypeCodeToNumericTypeCode(band.DataType))
self.stretch = imgutils.LUTStretcher(fill=2 ** (8 * dtype.itemsize))
self._stretch_initialized = False
[docs] def paint(self, painter, option, widget):
levelOfDetail = self._levelOfDetail(option, painter)
ovrband, ovrlevel, ovrindex = self._bestOvrLevel(self.gdalobj,
levelOfDetail)
x, y, w, h = self._clipRect(ovrband,
option.exposedRect.toAlignedRect(),
ovrlevel)
# @TODO: threshold check
# @WARNING: option.levelOfDetail is no more usable
#threshold = 1600*1600
#if w * h > threshold:
# newoption = QtGui.QStyleOptionGraphicsItem(option)
# newoption.levelOfDetail = option.levelOfDetail*threshold/(w*h)
# return self.paint(painter, newoption, widget)
data = ovrband.ReadAsArray(x, y, w, h)
if not self._stretch_initialized:
self.setDefaultStretch(data)
data = self.stretch(data)
image = numpy2qimage(data)
rect = self._targetRect(x, y, w, h, ovrlevel)
painter.drawImage(rect, image)
[docs]class GdalGraphicsItem(BaseGdalGraphicsItem):
Type = BaseGdalGraphicsItem.Type + 2
def __init__(self, band, parent=None, scene=None, **kwargs):
super(GdalGraphicsItem, self).__init__(band, parent, scene, **kwargs)
if gdal.DataTypeIsComplex(band.DataType):
# @TODO: raise ItemTypeError or NotImplementedError
typename = gdal.GetDataTypeName(band.DataType)
raise NotImplementedError('support for "%s" data type not '
'avalable' % typename)
[docs] def paint(self, painter, option, widget):
levelOfDetail = self._levelOfDetail(option, painter)
ovrband, ovrlevel, ovrindex = self._bestOvrLevel(self.gdalobj,
levelOfDetail)
x, y, w, h = self._clipRect(ovrband,
option.exposedRect.toAlignedRect(),
ovrlevel)
# @TODO: threshold check
# @WARNING: option.levelOfDetail is no more usable
#threshold = 1600*1600
#if w * h > threshold:
# newoption = QtGui.QStyleOptionGraphicsItem(option)
# newoption.levelOfDetail = (option.levelOfDetail *
# threshold / (w * h))
# return self.paint(painter, newoption, widget)
data = ovrband.ReadAsArray(x, y, w, h)
if not self._stretch_initialized:
self.setDefaultStretch(data)
data = self.stretch(data)
rect = self._targetRect(x, y, w, h, ovrlevel)
image = numpy2qimage(data)
painter.drawImage(rect, image)
[docs]class GdalComplexGraphicsItem(GdalGraphicsItem):
Type = GdalGraphicsItem.Type + 1
def __init__(self, band, parent=None, scene=None, **kwargs):
# @NOTE: skip GdalGraphicsItem __init__
BaseGdalGraphicsItem.__init__(self, band, parent, scene, **kwargs)
[docs] def dataRange(self, data=None):
if data:
data = np.abs(data)
return self._dataRange(self.gdalobj, data)
[docs] def paint(self, painter, option, widget):
levelOfDetail = self._levelOfDetail(option, painter)
ovrband, ovrlevel, ovrindex = self._bestOvrLevel(self.gdalobj,
levelOfDetail)
x, y, w, h = self._clipRect(ovrband,
option.exposedRect.toAlignedRect(),
ovrlevel)
# @TODO: threshold check
#threshold = 1600*1600
#if w * h > threshold:
# newoption = QtGui.QStyleOptionGraphicsItem(option)
# newoption.levelOfDetail = (option.levelOfDetail *
# threshold / (w * h))
# return self.paint(painter, newoption, widget)
data = ovrband.ReadAsArray(x, y, w, h)
data = np.abs(data)
if not self._stretch_initialized:
self.setDefaultStretch(data)
data = self.stretch(data)
rect = self._targetRect(x, y, w, h, ovrlevel)
image = numpy2qimage(data)
painter.drawImage(rect, image)
[docs]class GdalRgbGraphicsItem(BaseGdalGraphicsItem):
Type = BaseGdalGraphicsItem.Type + 3
def __init__(self, dataset, parent=None, scene=None, **kwargs):
if not gdalsupport.isRGB(dataset):
raise TypeError('RGB or RGBA iamge expected')
super(GdalRgbGraphicsItem, self).__init__(dataset, parent, scene,
**kwargs)
self.stretch = None
[docs] def paint(self, painter, option, widget):
band = self.gdalobj.GetRasterBand(1)
levelOfDetail = self._levelOfDetail(option, painter)
ovrband, ovrlevel, ovrindex = self._bestOvrLevel(band, levelOfDetail)
x, y, w, h = self._clipRect(ovrband,
option.exposedRect.toAlignedRect(),
ovrlevel)
dataset = self.gdalobj
data = gdalsupport.ovrRead(dataset, x, y, w, h, ovrindex)
rect = self._targetRect(x, y, w, h, ovrlevel)
image = numpy2qimage(data)
painter.drawImage(rect, image)
[docs]def graphicsItemFactory(gdalobj, parent=None, scene=None):
'''Factory function for GDAL graphics items.
Instantiates on object of the GDAL graphics item class taht best
fits the *gdalobj* passed as argument.
'''
if gdalsupport.isRGB(gdalobj):
logging.debug('new GdalRgbGraphicsItem')
return GdalRgbGraphicsItem(gdalobj, parent, scene)
elif gdalobj.DataType in (gdal.GDT_Byte, gdal.GDT_UInt16):
logging.debug('new GdalUIntGraphicsItem')
return UIntGdalGraphicsItem(gdalobj, parent, scene)
elif gdal.DataTypeIsComplex(gdalobj.DataType):
logging.debug('new GdalComplexGraphicsItem')
return GdalComplexGraphicsItem(gdalobj, parent, scene)
else:
logging.debug('new GdalGraphicsItem')
return GdalGraphicsItem(gdalobj, parent, scene)
