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diff --git a/catapult/telemetry/telemetry/internal/image_processing/cv_util.py b/catapult/telemetry/telemetry/internal/image_processing/cv_util.py
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+++ b/catapult/telemetry/telemetry/internal/image_processing/cv_util.py
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+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""This module provides implementations of common computer Vision operations."""
+
+from __future__ import division
+from telemetry.internal.util import external_modules
+
+np = external_modules.ImportRequiredModule('numpy')
+
+
+def AreLinesOrthogonal(line1, line2, tolerance):
+  """Returns true if lines are within tolerance radians of being orthogonal."""
+  # Map each line onto an angle between 0 and 180.
+  theta1 = np.arctan2(np.float(line1[1] - line1[3]),
+                      np.float(line1[0] - line1[2]))
+  theta2 = np.arctan2(np.float(line2[1] - line2[3]),
+                      np.float(line2[0] - line2[2]))
+  angle2 = abs(theta2 - theta1)
+  if angle2 >= np.pi:
+    angle2 -= np.pi
+  # If the difference between the angles is more than pi/2 - tolerance, the
+  # lines are not orthogonal.
+  return not abs(angle2 - (np.pi / 2.0)) > tolerance
+
+
+def FindLineIntersection(line1, line2):
+  """If the line segments intersect, returns True and their intersection.
+  Otherwise, returns False and the intersection of the line segments if they
+  were to be extended."""
+  # Compute g, and h, the factor by which each line must be extended to
+  # exactly touch the other line. If both are between 0 and 1, then the lines
+  # currently intersect. We use h to compute their intersection.
+  line1p1 = line1[:2]
+  line1p0 = line1[2:]
+  line2p1 = line2[:2]
+  line2p0 = line2[2:]
+  E = np.subtract(line1p1, line1p0)
+  F = np.subtract(line2p1, line2p0)
+  Pe = np.asfarray((-E[1], E[0]))
+  Pf = np.asfarray((-F[1], F[0]))
+  h = np.dot(np.subtract(line1p0, line2p0), Pe)
+  h = np.divide(h, np.dot(F, Pe))
+  g = np.dot(np.subtract(line2p0, line1p0), Pf)
+  g = np.divide(g, np.dot(E, Pf))
+  intersection = np.add(line2p0, np.dot(F, h))
+  intersect = (h >= -0.000001 and h <= 1.000001 and
+               g >= -0.000001 and g <= 1.000001)
+  return intersect, intersection
+
+
+def ExtendLines(lines, length):
+  """Extends lines in an array to a given length, maintaining the center
+  point. Does not necessarily maintain point order."""
+  half_length = length / 2.0
+  angles = np.arctan2(lines[:, 1] - lines[:, 3], lines[:, 0] - lines[:, 2])
+  xoffsets = half_length * np.cos(angles)
+  yoffsets = half_length * np.sin(angles)
+  centerx = (lines[:, 0] + lines[:, 2]) / 2.0
+  centery = (lines[:, 1] + lines[:, 3]) / 2.0
+  lines[:, 0] = centerx - xoffsets
+  lines[:, 2] = centerx + xoffsets
+  lines[:, 1] = centery - yoffsets
+  lines[:, 3] = centery + yoffsets
+  return lines
+
+
+def IsPointApproxOnLine(point, line, tolerance=1):
+  """Approximates distance between point and line for small distances using
+  the determinant and checks whether it's within the tolerance. Tolerance is
+  an approximate distance in pixels, precision decreases with distance."""
+  xd = line[0] - line[2]
+  yd = line[1] - line[3]
+  det = ((xd) * (point[1] - line[3])) - ((yd) * (point[0] - line[2]))
+  tolerance = float(tolerance) * (abs(xd) + abs(yd))
+  return abs(det) * 2.0 <= tolerance
+
+
+def SqDistances(points1, points2):
+  """Computes the square of the distance between two sets of points, or a
+  set of points and a point."""
+  d = np.square(points1 - points2)
+  return d[:, 0] + d[:, 1]
+
+
+def SqDistance(point1, point2):
+  """Computes the square of the distance between two points."""
+  d = np.square(point1 - point2)
+  return d[0] + d[1]