Beispiel #1
0
    def copyKeywords(self,
                     theSourceLayer,
                     theDestinationFile,
                     theExtraKeywords=None):
        """Helper to copy the keywords file from a source dataset
        to a destination dataset.

        e.g.::

            copyKeywords('foo.shp', 'bar.shp')

        Will result in the foo.keywords file being copied to bar.keyword.

        Optional argument extraKeywords is a dictionary with additional
        keywords that will be added to the destination file
        e.g::

            copyKeywords('foo.shp', 'bar.shp', {'resolution': 0.01})

        Args:
            * theSourceLayer - A QGIS QgsMapLayer instance.
            * theDestinationFile - the output filename that should be used
              to store the keywords in. It can be a .shp or a .keywords for
              exampled since the suffix will always be replaced with .keywords.
            * theExtraKeywords - a dict containing all the extra keywords to be
              written for the layer. The written keywords will consist of any
              original keywords from the source layer's keywords file and
              and the extra keywords (which will replace the source layers
              keywords if the key is identical).
        Returns:
            None.
        Raises:
            None
        """
        myKeywords = self.readKeywords(theSourceLayer)
        if theExtraKeywords is None:
            theExtraKeywords = {}
        myMessage = self.tr(
            'Expected extraKeywords to be a dictionary. Got %s' %
            str(type(theExtraKeywords))[1:-1])
        verify(isinstance(theExtraKeywords, dict), myMessage)
        # compute the output keywords file name
        myDestinationBase = os.path.splitext(theDestinationFile)[0]
        myNewDestination = myDestinationBase + '.keywords'
        # write the extra keywords into the source dict
        try:
            for key in theExtraKeywords:
                myKeywords[key] = theExtraKeywords[key]
            writeKeywordsToFile(myNewDestination, myKeywords)
        except Exception, e:
            myMessage = self.tr(
                'Failed to copy keywords file from :'
                '\n%s\nto\%s: %s' %
                (theSourceLayer.source(), myNewDestination, str(e)))
            raise Exception(myMessage)
Beispiel #2
0
    def copy_keywords(
            self,
            source_layer,
            destination_file,
            extra_keywords=None):
        """Helper to copy the keywords file from a source to a target dataset.

        e.g.::

            copyKeywords('foo.shp', 'bar.shp')

        Will result in the foo.keywords file being copied to bar.keyword.

        Optional argument extraKeywords is a dictionary with additional
        keywords that will be added to the destination file e.g::

            copyKeywords('foo.shp', 'bar.shp', {'resolution': 0.01})

        :param source_layer: A QGIS QgsMapLayer instance.
        :type source_layer: QgsMapLayer

        :param destination_file: The output filename that should be used
            to store the keywords in. It can be a .shp or a .keywords for
            example since the suffix will always be replaced with .keywords.
        :type destination_file: str

        :param extra_keywords: A dict containing all the extra keywords
            to be written for the layer. The written keywords will consist of
            any original keywords from the source layer's keywords file and
            and the extra keywords (which will replace the source layers
            keywords if the key is identical).
        :type extra_keywords: dict

        """
        keywords = self.read_keywords(source_layer)
        if extra_keywords is None:
            extra_keywords = {}
        message = self.tr(
            'Expected extraKeywords to be a dictionary. Got '
            '%s' % str(type(extra_keywords))[1:-1])
        verify(isinstance(extra_keywords, dict), message)
        # compute the output keywords file name
        destination_base = os.path.splitext(destination_file)[0]
        new_destination = destination_base + '.keywords'
        # write the extra keywords into the source dict
        try:
            for key in extra_keywords:
                keywords[key] = extra_keywords[key]
            writeKeywordsToFile(new_destination, keywords)
        except Exception, e:
            message = self.tr(
                'Failed to copy keywords file from : \n%s\nto\n%s: %s' % (
                source_layer.source(), new_destination, str(e)))
            raise Exception(message)
Beispiel #3
0
    def copy_keywords(self,
                      source_layer,
                      destination_file,
                      extra_keywords=None):
        """Helper to copy the keywords file from a source to a target dataset.

        e.g.::

            copyKeywords('foo.shp', 'bar.shp')

        Will result in the foo.keywords file being copied to bar.keyword.

        Optional argument extraKeywords is a dictionary with additional
        keywords that will be added to the destination file e.g::

            copyKeywords('foo.shp', 'bar.shp', {'resolution': 0.01})

        :param source_layer: A QGIS QgsMapLayer instance.
        :type source_layer: QgsMapLayer

        :param destination_file: The output filename that should be used
            to store the keywords in. It can be a .shp or a .keywords for
            example since the suffix will always be replaced with .keywords.
        :type destination_file: str

        :param extra_keywords: A dict containing all the extra keywords
            to be written for the layer. The written keywords will consist of
            any original keywords from the source layer's keywords file and
            and the extra keywords (which will replace the source layers
            keywords if the key is identical).
        :type extra_keywords: dict

        """
        myKeywords = self.read_keywords(source_layer)
        if extra_keywords is None:
            extra_keywords = {}
        myMessage = self.tr('Expected extraKeywords to be a dictionary. Got '
                            '%s' % str(type(extra_keywords))[1:-1])
        verify(isinstance(extra_keywords, dict), myMessage)
        # compute the output keywords file name
        myDestinationBase = os.path.splitext(destination_file)[0]
        myNewDestination = myDestinationBase + '.keywords'
        # write the extra keywords into the source dict
        try:
            for key in extra_keywords:
                myKeywords[key] = extra_keywords[key]
            writeKeywordsToFile(myNewDestination, myKeywords)
        except Exception, e:
            myMessage = self.tr(
                'Failed to copy keywords file from : \n%s\nto\n%s: %s' %
                (source_layer.source(), myNewDestination, str(e)))
            raise Exception(myMessage)
Beispiel #4
0
    def copyKeywords(self, theSourceLayer,
                     theDestinationFile, theExtraKeywords=None):
        """Helper to copy the keywords file from a source dataset
        to a destination dataset.

        e.g.::

            copyKeywords('foo.shp', 'bar.shp')

        Will result in the foo.keywords file being copied to bar.keyword.

        Optional argument extraKeywords is a dictionary with additional
        keywords that will be added to the destination file
        e.g::

            copyKeywords('foo.shp', 'bar.shp', {'resolution': 0.01})

        Args:
            * theSourceLayer - A QGIS QgsMapLayer instance.
            * theDestinationFile - the output filename that should be used
              to store the keywords in. It can be a .shp or a .keywords for
              exampled since the suffix will always be replaced with .keywords.
            * theExtraKeywords - a dict containing all the extra keywords to be
              written for the layer. The written keywords will consist of any
              original keywords from the source layer's keywords file and
              and the extra keywords (which will replace the source layers
              keywords if the key is identical).
        Returns:
            None.
        Raises:
            None
        """
        myKeywords = self.readKeywords(theSourceLayer)
        if theExtraKeywords is None:
            theExtraKeywords = {}
        myMessage = self.tr('Expected extraKeywords to be a dictionary. Got %s'
               % str(type(theExtraKeywords))[1:-1])
        verify(isinstance(theExtraKeywords, dict), myMessage)
        # compute the output keywords file name
        myDestinationBase = os.path.splitext(theDestinationFile)[0]
        myNewDestination = myDestinationBase + '.keywords'
        # write the extra keywords into the source dict
        try:
            for key in theExtraKeywords:
                myKeywords[key] = theExtraKeywords[key]
            writeKeywordsToFile(myNewDestination, myKeywords)
        except Exception, e:
            myMessage = self.tr('Failed to copy keywords file from :'
                           '\n%s\nto\%s: %s' %
                   (theSourceLayer.source(), myNewDestination, str(e)))
            raise Exception(myMessage)
Beispiel #5
0
def _clip_raster_layer(
        layer, extent, cell_size=None, extra_keywords=None):
    """Clip a Hazard or Exposure raster layer to the extents provided.

    The layer must be a raster layer or an exception will be thrown.

    .. note:: The extent *must* be in EPSG:4326.

    The output layer will always be in WGS84/Geographic.

    :param layer: A valid QGIS raster layer in EPSG:4326
    :type layer: QgsRasterLayer

    :param extent:  An array representing the exposure layer
           extents in the form [xmin, ymin, xmax, ymax]. It is assumed
           that the coordinates are in EPSG:4326 although currently
           no checks are made to enforce this.
           or:
           A QgsGeometry of type polygon.
           **Polygon clipping currently only supported for vector datasets.**
    :type extent: list(float), QgsGeometry

    :param cell_size: Cell size (in GeoCRS) which the layer should
            be resampled to. If not provided for a raster layer (i.e.
            theCellSize=None), the native raster cell size will be used.
    :type cell_size: float

    :returns: Output clipped layer (placed in the system temp dir).
    :rtype: QgsRasterLayer

    :raises: InvalidProjectionError - if input layer is a density
        layer in projected coordinates. See issue #123.

    """
    if not layer or not extent:
        message = tr('Layer or Extent passed to clip is None.')
        raise InvalidParameterError(message)

    if layer.type() != QgsMapLayer.RasterLayer:
        message = tr(
            'Expected a raster layer but received a %s.' %
            str(layer.type()))
        raise InvalidParameterError(message)

    working_layer = str(layer.source())

    # Check for existence of keywords file
    base, _ = os.path.splitext(working_layer)
    keywords_path = base + '.keywords'
    message = tr(
        'Input file to be clipped "%s" does not have the '
        'expected keywords file %s' % (
            working_layer,
            keywords_path
        ))
    verify(os.path.isfile(keywords_path), message)

    # Raise exception if layer is projected and refers to density (issue #123)
    # FIXME (Ole): Need to deal with it - e.g. by automatically reprojecting
    # the layer at this point and setting the native resolution accordingly
    # in its keywords.
    keywords = read_file_keywords(keywords_path)
    if 'datatype' in keywords and keywords['datatype'] == 'density':
        if str(layer.crs().authid()) != 'EPSG:4326':

            # This layer is not WGS84 geographic
            message = (
                'Layer %s represents density but has spatial reference "%s". '
                'Density layers must be given in WGS84 geographic coordinates, '
                'so please reproject and try again. For more information, '
                'see issue https://github.com/AIFDR/inasafe/issues/123' % (
                    working_layer,
                    layer.crs().toProj4()
                ))
            raise InvalidProjectionError(message)

    # We need to provide gdalwarp with a dataset for the clip
    # because unline gdal_translate, it does not take projwin.
    clip_kml = extent_to_kml(extent)

    # Create a filename for the clipped, resampled and reprojected layer
    handle, filename = tempfile.mkstemp('.tif', 'clip_', temp_dir())
    os.close(handle)
    os.remove(filename)

    # If no cell size is specified, we need to run gdalwarp without
    # specifying the output pixel size to ensure the raster dims
    # remain consistent.
    binary_list = which('gdalwarp')
    LOGGER.debug('Path for gdalwarp: %s' % binary_list)
    if len(binary_list) < 1:
        raise CallGDALError(
            tr('gdalwarp could not be found on your computer'))
    # Use the first matching gdalwarp found
    binary = binary_list[0]
    if cell_size is None:
        command = (
            '"%s" -q -t_srs EPSG:4326 -r near -cutline %s -crop_to_cutline '
            '-of GTiff "%s" "%s"' % (
                binary,
                clip_kml,
                working_layer,
                filename))
    else:
        command = (
            '"%s" -q -t_srs EPSG:4326 -r near -tr %f %f -cutline %s '
            '-crop_to_cutline -of GTiff "%s" "%s"' % (
                binary,
                cell_size,
                cell_size,
                clip_kml,
                working_layer,
                filename))

    LOGGER.debug(command)
    result = QProcess().execute(command)

    # For QProcess exit codes see
    # http://qt-project.org/doc/qt-4.8/qprocess.html#execute
    if result == -2:  # cannot be started
        message_detail = tr('Process could not be started.')
        message = tr(
            '<p>Error while executing the following shell command:'
            '</p><pre>%s</pre><p>Error message: %s'
            % (command, message_detail))
        raise CallGDALError(message)
    elif result == -1:  # process crashed
        message_detail = tr('Process crashed.')
        message = tr('<p>Error while executing the following shell command:</p>'
                     '<pre>%s</pre><p>Error message: %s' %
                     (command, message_detail))
        raise CallGDALError(message)

    # .. todo:: Check the result of the shell call is ok
    keyword_io = KeywordIO()
    keyword_io.copy_keywords(layer, filename, extra_keywords=extra_keywords)
    base_name = '%s clipped' % layer.name()
    layer = QgsRasterLayer(filename, base_name)

    return layer
Beispiel #6
0
def _clipRasterLayer(theLayer, theExtent, theCellSize=None,
                     theExtraKeywords=None):
    """Clip a Hazard or Exposure raster layer to the extents provided. The
    layer must be a raster layer or an exception will be thrown.

    .. note:: The extent *must* be in EPSG:4326.

    The output layer will always be in WGS84/Geographic.

    Args:

        * theLayer - a valid QGIS raster layer in EPSG:4326
        * theExtent -  an array representing the exposure layer
           extents in the form [xmin, ymin, xmax, ymax]. It is assumed
           that the coordinates are in EPSG:4326 although currently
           no checks are made to enforce this.
        * theCellSize - cell size (in GeoCRS) which the layer should
            be resampled to. If not provided for a raster layer (i.e.
            theCellSize=None), the native raster cell size will be used.

    Returns:
        Path to the output clipped layer (placed in the
        system temp dir).

    Raises:
       Exception if input layer is a density layer in projected coordinates -
       see issue #123

    """
    if not theLayer or not theExtent:
        myMessage = tr('Layer or Extent passed to clip is None.')
        raise InvalidParameterException(myMessage)

    if theLayer.type() != QgsMapLayer.RasterLayer:
        myMessage = tr('Expected a raster layer but received a %s.' %
               str(theLayer.type()))
        raise InvalidParameterException(myMessage)

    myWorkingLayer = str(theLayer.source())

    # Check for existence of keywords file
    myKeywordsPath = myWorkingLayer[:-4] + '.keywords'
    myMessage = tr('Input file to be clipped "%s" does not have the '
           'expected keywords file %s' % (myWorkingLayer,
                                          myKeywordsPath))
    verify(os.path.isfile(myKeywordsPath), myMessage)

    # Raise exception if layer is projected and refers to density (issue #123)
    # FIXME (Ole): Need to deal with it - e.g. by automatically reprojecting
    # the layer at this point and setting the native resolution accordingly
    # in its keywords.
    myKeywords = readKeywordsFromFile(myKeywordsPath)
    if 'datatype' in myKeywords and myKeywords['datatype'] == 'density':
        if theLayer.srs().epsg() != 4326:

            # This layer is not WGS84 geographic
            myMessage = ('Layer %s represents density but has spatial '
                         'reference "%s". Density layers must be given in '
                         'WGS84 geographic coordinates, so please reproject '
                         'and try again. For more information, see issue '
                         'https://github.com/AIFDR/inasafe/issues/123'
                         % (myWorkingLayer, theLayer.srs().toProj4()))
            raise InvalidProjectionException(myMessage)

    # We need to provide gdalwarp with a dataset for the clip
    # because unline gdal_translate, it does not take projwin.
    myClipKml = extentToKml(theExtent)

    # Create a filename for the clipped, resampled and reprojected layer
    myHandle, myFilename = tempfile.mkstemp('.tif', 'clip_',
                                            temp_dir())
    os.close(myHandle)
    os.remove(myFilename)

    # If no cell size is specified, we need to run gdalwarp without
    # specifying the output pixel size to ensure the raster dims
    # remain consistent.
    if theCellSize is None:
        myCommand = ('gdalwarp -q -t_srs EPSG:4326 -r near '
                     '-cutline %s -crop_to_cutline -of GTiff '
                     '"%s" "%s"' % (myClipKml,
                                    myWorkingLayer,
                                    myFilename))
    else:
        myCommand = ('gdalwarp -q -t_srs EPSG:4326 -r near -tr %f %f '
                     '-cutline %s -crop_to_cutline -of GTiff '
                     '"%s" "%s"' % (theCellSize,
                                    theCellSize,
                                    myClipKml,
                                    myWorkingLayer,
                                    myFilename))
    myExecutablePrefix = ''
    if sys.platform == 'darwin':  # Mac OS X
        # .. todo:: FIXME - softcode gdal version in this path
        myExecutablePrefix = ('/Library/Frameworks/GDAL.framework/'
                              'Versions/1.9/Programs/')
    myCommand = myExecutablePrefix + myCommand

    LOGGER.debug(myCommand)
    myResult = QProcess().execute(myCommand)

    # For QProcess exit codes see
    # http://qt-project.org/doc/qt-4.8/qprocess.html#execute
    if myResult == -2:  # cannot be started
        myMessageDetail = tr('Process could not be started.')
        myMessage = tr('<p>Error while executing the following shell command:'
                     '</p><pre>%s</pre><p>Error message: %s'
                     % (myCommand, myMessageDetail))
        raise CallGDALError(myMessage)
    elif myResult == -1:  # process crashed
        myMessageDetail = tr('Process could not be started.')
        myMessage = tr('<p>Error while executing the following shell command:'
                       '</p><pre>%s</pre><p>Error message: %s'
                       % (myCommand, myMessageDetail))
        raise CallGDALError(myMessage)

    # .. todo:: Check the result of the shell call is ok
    myKeywordIO = KeywordIO()
    myKeywordIO.copyKeywords(theLayer, myFilename,
                             theExtraKeywords=theExtraKeywords)
    return myFilename  # Filename of created file
Beispiel #7
0
def _clipRasterLayer(theLayer,
                     theExtent,
                     theCellSize=None,
                     theExtraKeywords=None):
    """Clip a Hazard or Exposure raster layer to the extents provided. The
    layer must be a raster layer or an exception will be thrown.

    .. note:: The extent *must* be in EPSG:4326.

    The output layer will always be in WGS84/Geographic.

    Args:

        * theLayer - a valid QGIS raster layer in EPSG:4326
        * theExtent either: an array representing the exposure layer
           extents in the form [xmin, ymin, xmax, ymax]. It is assumed
           that the coordinates are in EPSG:4326 although currently
           no checks are made to enforce this.
                    or: A QgsGeometry of type polygon. **Polygon clipping is
           currently only supported for vector datasets.**
        * theCellSize - cell size (in GeoCRS) which the layer should
            be resampled to. If not provided for a raster layer (i.e.
            theCellSize=None), the native raster cell size will be used.

    Returns:
        Path to the output clipped layer (placed in the
        system temp dir).

    Raises:
       Exception if input layer is a density layer in projected coordinates -
       see issue #123

    """
    if not theLayer or not theExtent:
        myMessage = tr('Layer or Extent passed to clip is None.')
        raise InvalidParameterError(myMessage)

    if theLayer.type() != QgsMapLayer.RasterLayer:
        myMessage = tr('Expected a raster layer but received a %s.' %
                       str(theLayer.type()))
        raise InvalidParameterError(myMessage)

    myWorkingLayer = str(theLayer.source())

    # Check for existence of keywords file
    myKeywordsPath = myWorkingLayer[:-4] + '.keywords'
    myMessage = tr('Input file to be clipped "%s" does not have the '
                   'expected keywords file %s' %
                   (myWorkingLayer, myKeywordsPath))
    verify(os.path.isfile(myKeywordsPath), myMessage)

    # Raise exception if layer is projected and refers to density (issue #123)
    # FIXME (Ole): Need to deal with it - e.g. by automatically reprojecting
    # the layer at this point and setting the native resolution accordingly
    # in its keywords.
    myKeywords = readKeywordsFromFile(myKeywordsPath)
    if 'datatype' in myKeywords and myKeywords['datatype'] == 'density':
        if str(theLayer.crs().authid()) != 'EPSG:4326':

            # This layer is not WGS84 geographic
            myMessage = ('Layer %s represents density but has spatial '
                         'reference "%s". Density layers must be given in '
                         'WGS84 geographic coordinates, so please reproject '
                         'and try again. For more information, see issue '
                         'https://github.com/AIFDR/inasafe/issues/123' %
                         (myWorkingLayer, theLayer.crs().toProj4()))
            raise InvalidProjectionError(myMessage)

    # We need to provide gdalwarp with a dataset for the clip
    # because unline gdal_translate, it does not take projwin.
    myClipKml = extentToKml(theExtent)

    # Create a filename for the clipped, resampled and reprojected layer
    myHandle, myFilename = tempfile.mkstemp('.tif', 'clip_', temp_dir())
    os.close(myHandle)
    os.remove(myFilename)

    # If no cell size is specified, we need to run gdalwarp without
    # specifying the output pixel size to ensure the raster dims
    # remain consistent.
    myBinaryList = which('gdalwarp')
    LOGGER.debug('Path for gdalwarp: %s' % myBinaryList)
    if len(myBinaryList) < 1:
        raise CallGDALError(tr('gdalwarp could not be found on your computer'))
    # Use the first matching gdalwarp found
    myBinary = myBinaryList[0]
    if theCellSize is None:
        myCommand = ('%s -q -t_srs EPSG:4326 -r near '
                     '-cutline %s -crop_to_cutline -of GTiff '
                     '"%s" "%s"' %
                     (myBinary, myClipKml, myWorkingLayer, myFilename))
    else:
        myCommand = ('%s -q -t_srs EPSG:4326 -r near -tr %f %f '
                     '-cutline %s -crop_to_cutline -of GTiff '
                     '"%s" "%s"' % (myBinary, theCellSize, theCellSize,
                                    myClipKml, myWorkingLayer, myFilename))

    LOGGER.debug(myCommand)
    myResult = QProcess().execute(myCommand)

    # For QProcess exit codes see
    # http://qt-project.org/doc/qt-4.8/qprocess.html#execute
    if myResult == -2:  # cannot be started
        myMessageDetail = tr('Process could not be started.')
        myMessage = tr('<p>Error while executing the following shell command:'
                       '</p><pre>%s</pre><p>Error message: %s' %
                       (myCommand, myMessageDetail))
        raise CallGDALError(myMessage)
    elif myResult == -1:  # process crashed
        myMessageDetail = tr('Process could not be started.')
        myMessage = tr('<p>Error while executing the following shell command:'
                       '</p><pre>%s</pre><p>Error message: %s' %
                       (myCommand, myMessageDetail))
        raise CallGDALError(myMessage)

    # .. todo:: Check the result of the shell call is ok
    myKeywordIO = KeywordIO()
    myKeywordIO.copyKeywords(theLayer,
                             myFilename,
                             theExtraKeywords=theExtraKeywords)
    return myFilename  # Filename of created file
Beispiel #8
0
def _clip_raster_layer(layer, extent, cell_size=None, extra_keywords=None):
    """Clip a Hazard or Exposure raster layer to the extents provided.

    The layer must be a raster layer or an exception will be thrown.

    .. note:: The extent *must* be in EPSG:4326.

    The output layer will always be in WGS84/Geographic.

    :param layer: A valid QGIS raster layer in EPSG:4326
    :type layer: QgsRasterLayer

    :param extent:  An array representing the exposure layer
           extents in the form [xmin, ymin, xmax, ymax]. It is assumed
           that the coordinates are in EPSG:4326 although currently
           no checks are made to enforce this.
           or:
           A QgsGeometry of type polygon.
           **Polygon clipping currently only supported for vector datasets.**
    :type extent: list(float), QgsGeometry

    :param cell_size: Cell size (in GeoCRS) which the layer should
            be resampled to. If not provided for a raster layer (i.e.
            theCellSize=None), the native raster cell size will be used.
    :type cell_size: float

    :returns: Output clipped layer (placed in the system temp dir).
    :rtype: QgsRasterLayer

    :raises: InvalidProjectionError - if input layer is a density
        layer in projected coordinates. See issue #123.

    """
    if not layer or not extent:
        message = tr('Layer or Extent passed to clip is None.')
        raise InvalidParameterError(message)

    if layer.type() != QgsMapLayer.RasterLayer:
        message = tr('Expected a raster layer but received a %s.' %
                     str(layer.type()))
        raise InvalidParameterError(message)

    working_layer = str(layer.source())

    # Check for existence of keywords file
    base, _ = os.path.splitext(working_layer)
    keywords_path = base + '.keywords'
    message = tr('Input file to be clipped "%s" does not have the '
                 'expected keywords file %s' % (working_layer, keywords_path))
    verify(os.path.isfile(keywords_path), message)

    # Raise exception if layer is projected and refers to density (issue #123)
    # FIXME (Ole): Need to deal with it - e.g. by automatically reprojecting
    # the layer at this point and setting the native resolution accordingly
    # in its keywords.
    keywords = read_file_keywords(keywords_path)
    if 'datatype' in keywords and keywords['datatype'] == 'density':
        if str(layer.crs().authid()) != 'EPSG:4326':

            # This layer is not WGS84 geographic
            message = (
                'Layer %s represents density but has spatial reference "%s". '
                'Density layers must be given in WGS84 geographic '
                'coordinates, so please reproject and try again. For more '
                'information, see issue '
                'https://github.com/AIFDR/inasafe/issues/123' %
                (working_layer, layer.crs().toProj4()))
            raise InvalidProjectionError(message)

    # We need to provide gdalwarp with a dataset for the clip
    # because unline gdal_translate, it does not take projwin.
    clip_kml = extent_to_kml(extent)

    # Create a filename for the clipped, resampled and reprojected layer
    handle, filename = tempfile.mkstemp('.tif', 'clip_', temp_dir())
    os.close(handle)
    os.remove(filename)

    # If no cell size is specified, we need to run gdalwarp without
    # specifying the output pixel size to ensure the raster dims
    # remain consistent.
    binary_list = which('gdalwarp')
    LOGGER.debug('Path for gdalwarp: %s' % binary_list)
    if len(binary_list) < 1:
        raise CallGDALError(tr('gdalwarp could not be found on your computer'))
    # Use the first matching gdalwarp found
    binary = binary_list[0]
    if cell_size is None:
        command = (
            '"%s" -q -t_srs EPSG:4326 -r near -cutline %s -crop_to_cutline '
            '-ot Float64 -of GTiff "%s" "%s"' %
            (binary, clip_kml, working_layer, filename))
    else:
        command = (
            '"%s" -q -t_srs EPSG:4326 -r near -tr %f %f -cutline %s '
            '-crop_to_cutline -ot Float64 -of GTiff "%s" "%s"' %
            (binary, cell_size, cell_size, clip_kml, working_layer, filename))

    LOGGER.debug(command)
    result = QProcess().execute(command)

    # For QProcess exit codes see
    # http://qt-project.org/doc/qt-4.8/qprocess.html#execute
    if result == -2:  # cannot be started
        message_detail = tr('Process could not be started.')
        message = tr('<p>Error while executing the following shell command:'
                     '</p><pre>%s</pre><p>Error message: %s' %
                     (command, message_detail))
        raise CallGDALError(message)
    elif result == -1:  # process crashed
        message_detail = tr('Process crashed.')
        message = tr(
            '<p>Error while executing the following shell command:</p>'
            '<pre>%s</pre><p>Error message: %s' % (command, message_detail))
        raise CallGDALError(message)

    # .. todo:: Check the result of the shell call is ok
    keyword_io = KeywordIO()
    keyword_io.copy_keywords(layer, filename, extra_keywords=extra_keywords)
    base_name = '%s clipped' % layer.name()
    layer = QgsRasterLayer(filename, base_name)

    return layer
Beispiel #9
0
def _clipRasterLayer(theLayer,
                     theExtent,
                     theCellSize=None,
                     theExtraKeywords=None):
    """Clip a Hazard or Exposure raster layer to the extents provided. The
    layer must be a raster layer or an exception will be thrown.

    .. note:: The extent *must* be in EPSG:4326.

    The output layer will always be in WGS84/Geographic.

    Args:

        * theLayer - a valid QGIS raster layer in EPSG:4326
        * theExtent -  an array representing the exposure layer
           extents in the form [xmin, ymin, xmax, ymax]. It is assumed
           that the coordinates are in EPSG:4326 although currently
           no checks are made to enforce this.
        * theCellSize - cell size (in GeoCRS) which the layer should
            be resampled to. If not provided for a raster layer (i.e.
            theCellSize=None), the native raster cell size will be used.

    Returns:
        Path to the output clipped layer (placed in the
        system temp dir).

    Raises:
       Exception if input layer is a density layer in projected coordinates -
       see issue #123

    """
    if not theLayer or not theExtent:
        myMessage = tr('Layer or Extent passed to clip is None.')
        raise InvalidParameterException(myMessage)

    if theLayer.type() != QgsMapLayer.RasterLayer:
        myMessage = tr('Expected a raster layer but received a %s.' %
                       str(theLayer.type()))
        raise InvalidParameterException(myMessage)

    myWorkingLayer = str(theLayer.source())

    # Check for existence of keywords file
    myKeywordsPath = myWorkingLayer[:-4] + '.keywords'
    myMessage = tr('Input file to be clipped "%s" does not have the '
                   'expected keywords file %s' %
                   (myWorkingLayer, myKeywordsPath))
    verify(os.path.isfile(myKeywordsPath), myMessage)

    # Raise exception if layer is projected and refers to density (issue #123)
    # FIXME (Ole): Need to deal with it - e.g. by automatically reprojecting
    # the layer at this point and setting the native resolution accordingly
    # in its keywords.
    myKeywords = readKeywordsFromFile(myKeywordsPath)
    if 'datatype' in myKeywords and myKeywords['datatype'] == 'density':
        if theLayer.srs().epsg() != 4326:

            # This layer is not WGS84 geographic
            myMessage = ('Layer %s represents density but has spatial '
                         'reference "%s". Density layers must be given in '
                         'WGS84 geographic coordinates, so please reproject '
                         'and try again. For more information, see issue '
                         'https://github.com/AIFDR/inasafe/issues/123' %
                         (myWorkingLayer, theLayer.srs().toProj4()))
            raise InvalidProjectionException(myMessage)

    # We need to provide gdalwarp with a dataset for the clip
    # because unline gdal_translate, it does not take projwin.
    myClipKml = extentToKml(theExtent)

    # Create a filename for the clipped, resampled and reprojected layer
    myHandle, myFilename = tempfile.mkstemp('.tif', 'clip_', temp_dir())
    os.close(myHandle)
    os.remove(myFilename)

    # If no cell size is specified, we need to run gdalwarp without
    # specifying the output pixel size to ensure the raster dims
    # remain consistent.
    if theCellSize is None:
        myCommand = ('gdalwarp -q -t_srs EPSG:4326 -r near '
                     '-cutline %s -crop_to_cutline -of GTiff '
                     '"%s" "%s"' % (myClipKml, myWorkingLayer, myFilename))
    else:
        myCommand = (
            'gdalwarp -q -t_srs EPSG:4326 -r near -tr %f %f '
            '-cutline %s -crop_to_cutline -of GTiff '
            '"%s" "%s"' %
            (theCellSize, theCellSize, myClipKml, myWorkingLayer, myFilename))
    myExecutablePrefix = ''
    if sys.platform == 'darwin':  # Mac OS X
        # .. todo:: FIXME - softcode gdal version in this path
        myExecutablePrefix = ('/Library/Frameworks/GDAL.framework/'
                              'Versions/1.9/Programs/')
    myCommand = myExecutablePrefix + myCommand

    # For debugging only
    # myCommand = myExecutablePrefix + myCommand
    # myFile = file('C:/temp/command.txt', 'wt')
    # myFile.write(myCommand)
    # myFile.close()
    # Now run GDAL warp scottie...
    LOGGER.debug(myCommand)
    try:
        myResult = call(myCommand, shell=True)
        del myResult
    except CalledProcessError, e:
        myMessage = tr('<p>Error while executing the following shell command:'
                       '</p><pre>%s</pre><p>Error message: %s' %
                       (myCommand, str(e)))
        # shameless hack - see https://github.com/AIFDR/inasafe/issues/141
        if sys.platform == 'darwin':  # Mac OS X
            if 'Errno 4' in str(e):
                # continue as the error seems to be non critical
                pass
            else:
                raise Exception(myMessage)
        else:
            raise Exception(myMessage)