def getGdcTransformFromPixelTransform(imageSize, pixelTransform, refImageGdcTransform):
'''Converts an image-to-image transform chained with a GDC transform
to a pixel to GDC transform for this image.'''
# Convert the image-to-image transform parameters to a class
temp = numpy.array([tform[0:3], tform[3:6], tform[6:9]] )
imageToRefTransform = transform.ProjectiveTransform(temp)
newImageSize = ImageFetcher.miscUtilities.getImageSize(newImagePath)
# Generate a list of point pairs
imagePoints = []
gdcPoints = []
# Loop through an evenly spaced grid of pixels in the new image
# - For each pixel, compute the desired output coordinate
pointPixelSpacing = (newImageSize[0] + newImageSize[1]) / 20 # Results in about 100 points
for r in range(0, newImageSize[0], pointPixelSpacing):
for c in range(0, newImageSize[1], pointPixelSpacing):
# Get pixel in new image and matching pixel in the reference image,
# then pass that into the GDC transform.
thisPixel = numpy.array([float(c), float(r)])
pixelInRefImage = pixelTransform.forward(thisPixel)
gdcCoordinate = refImageGdcTransform.forward(pixelInRefImage)
imagePoints.append(thisPixel)
gdcPoints.append(gdcCoordinate)
# Compute a transform object that converts from the new image to projected coordinates
imageToGdcTransform = transform.getTransform(numpy.asarray(worldPoints),
numpy.asarray(gdcPoints))
return imageToGdcTransform
def getPixelToGdcTransform(imagePath, pixelToProjectedTransform=None):
'''Returns a pixel to GDC transform.
The input image must either be a nicely georegistered image from Earth Engine
or a pixel to projected coordinates transform must be provided.'''
if pixelToProjectedTransform:
# Have image to projected transform, convert it to an image to GDC transform.
# Use the simple file info call (the input file may not have geo information)
(width, height) = IrgGeoFunctions.getImageSize(imagePath)
imagePoints = []
gdcPoints = []
# Loop through a spaced out grid of pixels in the image
pointPixelSpacing = (width +
height) / 20 # Results in about 100 points
for r in range(0, width, pointPixelSpacing):
for c in range(0, height, pointPixelSpacing):
# This pixel --> projected coords --> lonlat coord
thisPixel = numpy.array([float(c), float(r)])
projectedCoordinate = pixelToProjectedTransform.forward(
thisPixel)
gdcCoordinate = transform.metersToLatLon(projectedCoordinate)
imagePoints.append(thisPixel)
gdcPoints.append(gdcCoordinate)
# Solve for a transform with all of these point pairs
pixelToGdcTransform = transform.getTransform(
numpy.asarray(gdcPoints), numpy.asarray(imagePoints))
else: # Using a reference image from EE which will have nice bounds.
# Use the more thorough file info call
stats = IrgGeoFunctions.getImageGeoInfo(imagePath, False)
(width, height) = stats['image_size']
(minLon, maxLon, minLat, maxLat) = stats['lonlat_bounds']
# Make a transform from ref pixel to GDC using metadata on disk
xScale = (maxLon - minLon) / width
yScale = (maxLat - minLat) / height
transformMatrix = numpy.array([[xScale, 0, minLon],
[0, -yScale, maxLat], [0, 0, 1]])
pixelToGdcTransform = transform.LinearTransform(transformMatrix)
return pixelToGdcTransform
def updateAlignment(self):
toPts, fromPts = transform.splitPoints(self.extras.points)
tform = transform.getTransform(toPts, fromPts)
self.extras.transform = tform.getJsonDict()
289.4999999999986
],
[
-10824770.036926387,
2994035.003758455,
335.50000000000034,
424.50000000000097
]
]
TO_PTS, FROM_PTS = transform.splitPoints(POINTS)
N = len(POINTS)
def testTransformClass(cls):
tform = cls.fit(TO_PTS, FROM_PTS)
toPtsApprox = transform.forwardPts(tform, FROM_PTS)
#print toPtsApprox
print ('%s: %e'
% (cls.__name__,
numpy.linalg.norm(toPtsApprox - TO_PTS) / N))
testTransformClass(transform.TranslateTransform)
testTransformClass(transform.RotateScaleTranslateTransform)
testTransformClass(transform.AffineTransform)
testTransformClass(transform.ProjectiveTransform)
testTransformClass(transform.QuadraticTransform)
testTransformClass(transform.QuadraticTransform2)
print transform.getTransform(TO_PTS, FROM_PTS)
def updateAlignment(self):
toPts, fromPts = transform.splitPoints(self.extras.points)
tform = transform.getTransform(toPts, fromPts)
self.extras.transform = tform.getJsonDict()
def qualityGdalwarp(imagePath, outputPath, imagePoints, gdcPoints):
'''Use some workarounds to get a higher quality gdalwarp output than is normally possible.'''
# Generate a high resolution grid of fake GCPs based on a transform we compute,
# then call gdalwarp using a high order polynomial to accurately match our transform.
#trans = transform.ProjectiveTransform.fit(numpy.asarray(gdcPoints),numpy.asarray(imagePoints))ls
trans = transform.getTransform(numpy.asarray(gdcPoints),numpy.asarray(imagePoints))
transformName = trans.getJsonDict()['type']
tempPath = outputPath + '-temp.tif'
# Generate a temporary image containing the grid of fake GCPs
cmd = ('gdal_translate -co "COMPRESS=LZW" -co "tiled=yes" -co "predictor=2" -a_srs "'
+ OUTPUT_PROJECTION +'" '+ imagePath +' '+ tempPath)
# Generate the GCPs in a grid, keeping the total under about 500 points so
# that GDAL does not complain.
(width, height) = IrgGeoFunctions.getImageSize(imagePath)
xStep = width /22
yStep = height/22
MAX_DEG_SIZE = 20
minLon = 999 # Keep track of the lonlat size and don't write if it is too big.
minLat = 999 # - This would work better if it was in pixels, but how to get that size?
maxLon = -999
maxLat = -999
for r in range(0,height,yStep):
for c in range(0,width,xStep):
pixel = (c,r)
lonlat = trans.forward(pixel)
cmd += ' -gcp '+ str(c) +' '+str(r) +' '+str(lonlat[0]) +' '+str(lonlat[1])
if lonlat[0] < minLon:
minLon = lonlat[0]
if lonlat[1] < minLat:
minLat = lonlat[1]
if lonlat[0] > maxLon:
maxLon = lonlat[0]
if lonlat[1] > maxLat:
maxLat = lonlat[1]
#print cmd
os.system(cmd)
if max((maxLon - minLon), (maxLat - minLat)) > MAX_DEG_SIZE:
raise Exception('Warped image is too large to generate!\n'
'-> LonLat bounds: ' + str((minLon, minLat, maxLon, maxLat)))
# Now generate a warped geotiff.
# - "order 2" looks terrible with fewer GCPs, but "order 1" does not accurately
# capture the footprint of higher tilt images.
# - tps seems to work well with the evenly spaced grid of virtual GCPs.
cmd = ('gdalwarp -co "COMPRESS=LZW" -co "tiled=yes" -co "predictor=2"'
+ ' -dstalpha -overwrite -tps -multi -r cubic -t_srs "'
+ OUTPUT_PROJECTION +'" ' + tempPath +' '+ outputPath)
print cmd
os.system(cmd)
# Check output and cleanup
os.remove(tempPath)
if not os.path.exists(outputPath):
raise Exception('Failed to create warped geotiff file: ' + outputPath)
return transformName
],
[
-13045724.330780469, 3825669.8715011734, 68.50000000000003,
289.4999999999986
],
[
-10824770.036926387, 2994035.003758455, 335.50000000000034,
424.50000000000097
]]
TO_PTS, FROM_PTS = transform.splitPoints(POINTS)
N = len(POINTS)
def testTransformClass(cls):
tform = cls.fit(TO_PTS, FROM_PTS)
toPtsApprox = transform.forwardPts(tform, FROM_PTS)
#print toPtsApprox
print('%s: %e' %
(cls.__name__, numpy.linalg.norm(toPtsApprox - TO_PTS) / N))
testTransformClass(transform.TranslateTransform)
testTransformClass(transform.RotateScaleTranslateTransform)
testTransformClass(transform.AffineTransform)
testTransformClass(transform.ProjectiveTransform)
testTransformClass(transform.QuadraticTransform)
testTransformClass(transform.QuadraticTransform2)
print transform.getTransform(TO_PTS, FROM_PTS)
