def get_pixel_dimensions(image, target_meters_per_pixel_dimensions):
metric_dimensions = image.to_metric_dimensions(image.pixel_dimensions)
try:
pixel_width = round_number(metric_dimensions[0] / float(
target_meters_per_pixel_dimensions[0]))
pixel_height = round_number(metric_dimensions[1] / float(
target_meters_per_pixel_dimensions[1]))
except TypeError:
pixel_width, pixel_height = image.pixel_dimensions
return pixel_width, pixel_height
def estimate_negative_count(image_scope, positive_pixel_centers):
canvas = np.zeros(tuple(image_scope.pixel_dimensions), dtype='bool')
# Compute the positive pixel area
for index, positive_pixel_center in enumerate(positive_pixel_centers):
pixel_frame = image_scope.get_pixel_frame_from_pixel_center(
positive_pixel_center)
(pixel_x, pixel_y), (pixel_width, pixel_height) = pixel_frame
canvas[pixel_x:pixel_x + pixel_width,
pixel_y:pixel_y + pixel_height] = 1
positive_pixel_area = canvas.sum()
# Compute the negative pixel area
image_pixel_area = reduce(operator.mul, image_scope.pixel_dimensions)
negative_pixel_area = image_pixel_area - positive_pixel_area
# Compute the ratio of negatives to positives
negative_area_over_positive_area = negative_pixel_area / float(
positive_pixel_area)
# Estimate the required number of negative examples
positive_count = len(positive_pixel_centers)
return round_number(negative_area_over_positive_area * positive_count)
def _to_pixel_width(self, projected_width):
g0, g1, g2, g3, g4, g5 = self.calibration_pack
return round_number(projected_width / float(g1))
def _to_pixel_height(self, projected_height):
g0, g1, g2, g3, g4, g5 = self.calibration_pack
return round_number(projected_height / float(g5))
return round_number(projected_height / float(g5))
def to_projected_xy(self, (pixel_x, pixel_y)):
'Get projected coordinates given pixel coordinates'
g0, g1, g2, g3, g4, g5 = self.calibration_pack
projected_x = g0 + pixel_x * g1 + pixel_y * g2
projected_y = g3 + pixel_x * g4 + pixel_y * g5
return np.array([projected_x, projected_y])
def to_pixel_xy(self, (projected_x, projected_y)):
'Get pixel coordinates given projected coordinates'
g0, g1, g2, g3, g4, g5 = self.calibration_pack
k = float(g1 * g5 - g2 * g4)
x = -g0 * g5 + g2 * g3 - g2 * projected_y + g5 * projected_x
y = -g1 * (g3 - projected_y) + g4 * (g0 - projected_x)
return np.array([round_number(x / k), round_number(y / k)])
class MetricCalibration(ProjectedCalibration):
def __init__(self, calibration_pack, proj4):
super(MetricCalibration, self).__init__(calibration_pack)
self.proj4 = proj4
self._metric_proj4 = self._get_metric_proj4()
self._in_metric_projection = self.proj4 == self._metric_proj4
self._transform_to_metric_xy = get_transformPoint(
self.proj4, self._metric_proj4)
self._transform_to_projected_xy = get_transformPoint(
self._metric_proj4, self.proj4)
self._metric_xy1 = self._to_metric_xy((0, 0))
def _become(self, c):