def testPalettedClassDataToString(self):
classes = [
QgsPalettedRasterRenderer.Class(1, QColor(0, 255, 0), 'class 2'),
QgsPalettedRasterRenderer.Class(3, QColor(255, 0, 0), 'class 1')
]
self.assertEqual(QgsPalettedRasterRenderer.classDataToString(classes),
'1 0 255 0 255 class 2\n3 255 0 0 255 class 1')
# must be sorted by value to work OK in ArcMap
classes = [
QgsPalettedRasterRenderer.Class(4, QColor(0, 255, 0), 'class 2'),
QgsPalettedRasterRenderer.Class(3, QColor(255, 0, 0), 'class 1')
]
self.assertEqual(QgsPalettedRasterRenderer.classDataToString(classes),
'3 255 0 0 255 class 1\n4 0 255 0 255 class 2')
def testPalettedRendererWithNegativeColorValue(self):
""" test paletted raster renderer with negative values in color table"""
path = os.path.join(unitTestDataPath('raster'),
'hub13263.vrt')
info = QFileInfo(path)
base_name = info.baseName()
layer = QgsRasterLayer(path, base_name)
self.assertTrue(layer.isValid(), 'Raster not loaded: {}'.format(path))
renderer = QgsPalettedRasterRenderer(layer.dataProvider(), 1,
[QgsPalettedRasterRenderer.Class(-1, QColor(0, 255, 0), 'class 2'),
QgsPalettedRasterRenderer.Class(3, QColor(255, 0, 0), 'class 1')])
self.assertEqual(renderer.nColors(), 2)
self.assertEqual(renderer.usesBands(), [1])
def apply_symbology(rlayer, rband, symbology):
"""Apply symbology to raster layer using Paletted/Unique values"""
paletted_classes = []
for name, value, color in symbology:
paletted_classes.append(
QgsPalettedRasterRenderer.Class(
value, QColor(color[0], color[1], color[2], color[3]), name))
renderer = QgsPalettedRasterRenderer(rlayer.dataProvider(), rband,
paletted_classes)
# Set renderer for raster layer
rlayer.setRenderer(renderer)
# set the opacity to the layer based on the opacity set in active layer UI
from ThRasE.gui.main_dialog import ThRasEDialog
active_layer = next((active_layer for active_layer in [
al for als in [
view_widget.active_layers
for view_widget in ThRasEDialog.view_widgets
] for al in als
] if active_layer.layer == rlayer), False)
if active_layer:
if rlayer.type() == QgsMapLayer.VectorLayer:
rlayer.setOpacity(active_layer.opacity / 100.0)
else:
rlayer.renderer().setOpacity(active_layer.opacity / 100.0)
# Repaint
if hasattr(rlayer, 'setCacheImage'):
rlayer.setCacheImage(None)
rlayer.triggerRepaint()
def testPalettedBand(self):
""" test paletted raster render band"""
path = os.path.join(unitTestDataPath(), 'landsat_4326.tif')
info = QFileInfo(path)
base_name = info.baseName()
layer = QgsRasterLayer(path, base_name)
self.assertTrue(layer.isValid(), 'Raster not loaded: {}'.format(path))
renderer = QgsPalettedRasterRenderer(layer.dataProvider(), 2, [
QgsPalettedRasterRenderer.Class(137, QColor(0, 255, 0), 'class 2'),
QgsPalettedRasterRenderer.Class(138, QColor(255, 0, 0), 'class 1'),
QgsPalettedRasterRenderer.Class(139, QColor(0, 0, 255), 'class 1')
])
layer.setRenderer(renderer)
ms = QgsMapSettings()
ms.setLayers([layer])
ms.setExtent(layer.extent())
checker = QgsRenderChecker()
checker.setControlName("expected_paletted_renderer_band2")
checker.setMapSettings(ms)
self.assertTrue(checker.runTest("expected_paletted_renderer_band2"),
"Paletted rendering test failed")
renderer = QgsPalettedRasterRenderer(layer.dataProvider(), 3, [
QgsPalettedRasterRenderer.Class(120, QColor(0, 255, 0), 'class 2'),
QgsPalettedRasterRenderer.Class(123, QColor(255, 0, 0), 'class 1'),
QgsPalettedRasterRenderer.Class(124, QColor(0, 0, 255), 'class 1')
])
layer.setRenderer(renderer)
ms = QgsMapSettings()
ms.setLayers([layer])
ms.setExtent(layer.extent())
checker = QgsRenderChecker()
checker.setControlName("expected_paletted_renderer_band3")
checker.setMapSettings(ms)
self.assertTrue(checker.runTest("expected_paletted_renderer_band3"),
"Paletted rendering test failed")
def testPaletted(self):
""" test paletted raster renderer with raster with color table"""
path = os.path.join(unitTestDataPath('raster'),
'with_color_table.tif')
info = QFileInfo(path)
base_name = info.baseName()
layer = QgsRasterLayer(path, base_name)
self.assertTrue(layer.isValid(), 'Raster not loaded: {}'.format(path))
renderer = QgsPalettedRasterRenderer(layer.dataProvider(), 1,
[QgsPalettedRasterRenderer.Class(1, QColor(0, 255, 0), 'class 2'),
QgsPalettedRasterRenderer.Class(3, QColor(255, 0, 0), 'class 1')])
self.assertEqual(renderer.nColors(), 2)
self.assertEqual(renderer.usesBands(), [1])
# test labels
self.assertEqual(renderer.label(1), 'class 2')
self.assertEqual(renderer.label(3), 'class 1')
self.assertFalse(renderer.label(101))
# test legend symbology - should be sorted by value
legend = renderer.legendSymbologyItems()
self.assertEqual(legend[0][0], 'class 2')
self.assertEqual(legend[1][0], 'class 1')
self.assertEqual(legend[0][1].name(), '#00ff00')
self.assertEqual(legend[1][1].name(), '#ff0000')
# test retrieving classes
classes = renderer.classes()
self.assertEqual(classes[0].value, 1)
self.assertEqual(classes[1].value, 3)
self.assertEqual(classes[0].label, 'class 2')
self.assertEqual(classes[1].label, 'class 1')
self.assertEqual(classes[0].color.name(), '#00ff00')
self.assertEqual(classes[1].color.name(), '#ff0000')
# test set label
# bad index
renderer.setLabel(1212, 'bad')
renderer.setLabel(3, 'new class')
self.assertEqual(renderer.label(3), 'new class')
# color ramp
r = QgsLimitedRandomColorRamp(5)
renderer.setSourceColorRamp(r)
self.assertEqual(renderer.sourceColorRamp().type(), 'random')
self.assertEqual(renderer.sourceColorRamp().count(), 5)
# clone
new_renderer = renderer.clone()
classes = new_renderer.classes()
self.assertEqual(classes[0].value, 1)
self.assertEqual(classes[1].value, 3)
self.assertEqual(classes[0].label, 'class 2')
self.assertEqual(classes[1].label, 'new class')
self.assertEqual(classes[0].color.name(), '#00ff00')
self.assertEqual(classes[1].color.name(), '#ff0000')
self.assertEqual(new_renderer.sourceColorRamp().type(), 'random')
self.assertEqual(new_renderer.sourceColorRamp().count(), 5)
# write to xml and read
doc = QDomDocument('testdoc')
elem = doc.createElement('qgis')
renderer.writeXml(doc, elem)
restored = QgsPalettedRasterRenderer.create(elem.firstChild().toElement(), layer.dataProvider())
self.assertTrue(restored)
self.assertEqual(restored.usesBands(), [1])
classes = restored.classes()
self.assertTrue(classes)
self.assertEqual(classes[0].value, 1)
self.assertEqual(classes[1].value, 3)
self.assertEqual(classes[0].label, 'class 2')
self.assertEqual(classes[1].label, 'new class')
self.assertEqual(classes[0].color.name(), '#00ff00')
self.assertEqual(classes[1].color.name(), '#ff0000')
self.assertEqual(restored.sourceColorRamp().type(), 'random')
self.assertEqual(restored.sourceColorRamp().count(), 5)
# render test
layer.setRenderer(renderer)
ms = QgsMapSettings()
ms.setLayers([layer])
ms.setExtent(layer.extent())
checker = QgsRenderChecker()
checker.setControlName("expected_paletted_renderer")
checker.setMapSettings(ms)
self.assertTrue(checker.runTest("expected_paletted_renderer"), "Paletted rendering test failed")
def on_cannyPushButton_clicked(self):
raster_layer_name = self.rasterLayerComboBox.currentText()
raster_layer = QgsProject.instance().mapLayersByName(
raster_layer_name)[0]
provider = raster_layer.dataProvider()
extent = provider.extent()
rows = raster_layer.height()
cols = raster_layer.width()
# 读取栅格值
block = provider.block(1, extent, cols, rows)
img = np.zeros([rows, cols, 3], np.uint8)
band_num = 3
for band_index in range(band_num):
block = provider.block(band_index + 1, extent, cols, rows)
# for row_index in range(rows):
# for col_index in range(cols):
# img[row_index][col_index][band_index] = block.value(
# row_index, col_index)
img[:, :,
band_index] = np.array(block.data()).reshape([rows, cols])
print(img)
print(img.shape)
edges = cv2.Canny(img, 200, 400, 15)
plt.subplot(121)
plt.imshow(img)
plt.title('Original Image')
plt.xticks([])
plt.yticks([])
plt.subplot(122)
plt.imshow(edges, cmap='gray')
plt.title('Edge Image')
plt.xticks([])
plt.yticks([])
plt.show()
cv2.imwrite(r'edge_result.jpg', edges)
# 写入Tiff
driver = gdal.GetDriverByName('GTiff')
# 创建图像
print(f'cols {cols}, rows {rows}')
ds = driver.Create('edge_result.tif',
xsize=cols,
ysize=rows,
bands=1,
eType=gdal.GDT_Byte)
# 设置参考坐标系
crs_wkt = raster_layer.crs().toWkt()
ds.SetProjection(crs_wkt)
print(crs_wkt)
# srs = osr.SpatialReference()
# srs.SetUTM(12, 1)
# srs.SetWellKnownGeogCS('WGS84')
# ds.SetProjection(srs.ExportToWkt())
# 设置Tiff的图像转换参数
transformParam = [
extent.xMinimum(), (extent.width() / cols), 0,
extent.yMaximum(), 0, -(extent.height() / rows)
]
ds.SetGeoTransform(transformParam)
print(transformParam)
# 写入数据
ds.GetRasterBand(1).WriteArray(edges[:, :])
# 关闭文件
ds = None
# 添加至图层并设置样式
rlayer = QgsRasterLayer('edge_result.tif', "result tif layer")
QgsProject.instance().addMapLayer(rlayer)
palette_raster_render = QgsPalettedRasterRenderer(
rlayer.dataProvider(), 1, [
QgsPalettedRasterRenderer.Class(0, QtGui.QColor(0, 0, 0, 0)),
QgsPalettedRasterRenderer.Class(255,
QtGui.QColor(255, 0, 0, 255))
])
rlayer.setRenderer(palette_raster_render)
