Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

server-side otsu #13

Open
wants to merge 1 commit into
base: main
Choose a base branch
from
Open

server-side otsu #13

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
62 changes: 38 additions & 24 deletions eepackages/utils.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -73,36 +73,44 @@ def computeThresholdUsingOtsu(image, scale, bounds, cannyThreshold, cannySigma,
edge = ee.Algorithms.CannyEdgeDetector(image, cannyThreshold, cannySigma)
edge = edge.multiply(mask)

if minEdgeLength:
connected = edge.mask(edge).lt(
cannyThreshold).connectedPixelCount(200, True)

edgeLong = connected.gte(minEdgeLength)

def filter_small_edge_length(e, canny_threshold, min_edge_length):
connected = e.mask(e).lt(
canny_threshold).connectedPixelCount(200, True)
# if debug:
# print('Edge length: ', ui.Chart.image.histogram(connected, bounds, scale, buckets))
# Map.addLayer(edge.mask(edge), {palette:['ff0000']}, 'edges (short)', false);
return connected.gte(min_edge_length)

edge = edgeLong
edge = ee.Image(ee.Algorithms.If(
minEdgeLength,
filter_small_edge_length(edge, cannyThreshold, minEdgeLength),
edge
))

# buffer around NDWI edges
edgeBuffer = edge.focal_max(ee.Number(scale), 'square', 'meters')

if minEdgeValue:
edgeMin = image.reduceNeighborhood(
ee.Reducer.min(), ee.Kernel.circle(ee.Number(scale), 'meters'))

edgeBuffer = edgeBuffer.updateMask(edgeMin.gt(minEdgeValue))
def filter_small_edge_values(i, edge_buffer, sc, min_edge_value):
edgeMin = i.reduceNeighborhood(
ee.Reducer.min(), ee.Kernel.circle(ee.Number(sc), 'meters'))

# if debug:
# Map.addLayer(edge.updateMask(edgeBuffer), {palette:['ff0000']}, 'edge min', false);

if minEdgeGradient:
edgeGradient = image.gradient().abs().reduce(
ee.Reducer.max()).updateMask(edgeBuffer.mask())
return edge_buffer.updateMask(edgeMin.gt(min_edge_value))

edgeBuffer = ee.Image(ee.Algorithms.If(
minEdgeValue,
filter_small_edge_values(image, edgeBuffer, scale, minEdgeValue),
edgeBuffer
))

def filter_small_edge_gradient(i, edge_buffer, bnds, sc, min_edge_gradient):
edge_gradient = i.gradient().abs().reduce(
ee.Reducer.max()).updateMask(edge_buffer.mask())

edgeGradientTh = ee.Number(edgeGradient.reduceRegion(
ee.Reducer.percentile([minEdgeGradient]), bounds, scale).values().get(0))
edge_gradient_th = ee.Number(edge_gradient.reduceRegion(
ee.Reducer.percentile([min_edge_gradient]), bnds, sc).values().get(0))

# if debug:
# print('Edge gradient threshold: ', edgeGradientTh)
Expand All @@ -111,7 +119,14 @@ def computeThresholdUsingOtsu(image, scale, bounds, cannyThreshold, cannySigma,

# print('Edge gradient: ', ui.Chart.image.histogram(edgeGradient, bounds, scale, buckets))

edgeBuffer = edgeBuffer.updateMask(edgeGradient.gt(edgeGradientTh))
return edge_buffer.updateMask(edge_gradient.gt(edge_gradient_th))


edgeBuffer = ee.Image(ee.Algorithms.If(
minEdgeGradient,
filter_small_edge_gradient(image, edgeBuffer, bounds, scale, minEdgeGradient),
edgeBuffer
))

edge = edge.updateMask(edgeBuffer)
edgeBuffer = edge.focal_max(
Expand All @@ -130,7 +145,7 @@ def computeThresholdUsingOtsu(image, scale, bounds, cannyThreshold, cannySigma,
'bucketMeans'), otsu(hist), minValue)
threshold = ee.Number(threshold)

if debug:
# if debug:
# // experimental
# // var jrc = ee.Image('JRC/GSW1_0/GlobalSurfaceWater').select('occurrence')
# // var jrcTh = ee.Number(ee.Dictionary(jrc.updateMask(edge).reduceRegion(ee.Reducer.mode(), bounds, scale)).values().get(0))
Expand All @@ -140,16 +155,15 @@ def computeThresholdUsingOtsu(image, scale, bounds, cannyThreshold, cannySigma,

# Map.addLayer(edge.mask(edge), {palette:['ff0000']}, 'edges', true);

print('Threshold: ', threshold)
# print('Threshold: ', threshold)

# print('Image values:', ui.Chart.image.histogram(image, bounds, scale, buckets));
# print('Image values (edge): ', ui.Chart.image.histogram(imageEdge, bounds, scale, buckets));
# Map.addLayer(mask.mask(mask), {palette:['000000']}, 'image mask', false);

if minValue is not None:
return threshold.max(minValue)
else:
return threshold
threshold_ret = ee.Number(ee.Algorithms.If(minValue, threshold.max(minValue), threshold))

return threshold_ret


def focalMin(image: ee.Image, radius: float):
Expand Down