From 1ffd8d89bd6a60b23c22a887e3c40f9f592f2b74 Mon Sep 17 00:00:00 2001
From: Paul McCarthy <pauld.mccarthy@gmail.com>
Date: Thu, 23 Jul 2015 13:34:15 +0100
Subject: [PATCH] I have no idea how bricon <-> display range sync was working
at all. Replaced the old contrast scaling equation with somthing simpler to
invert (and replaced the previously-incorrect inverted scale->contrast
equation). VolumeOpts was incorrectly flipping the resulting bricon values,
as well.
Other small changes - fsldirdlg layout tweak, and ActionButton now does
not require the action to be listed in the strings module.
---
fsl/fslview/actions/__init__.py | 13 ++---
fsl/fslview/colourmaps.py | 64 +++++++++++++-----------
fsl/fslview/displaycontext/volumeopts.py | 4 +-
fsl/utils/fsldirdlg.py | 4 +-
4 files changed, 45 insertions(+), 40 deletions(-)
diff --git a/fsl/fslview/actions/__init__.py b/fsl/fslview/actions/__init__.py
index 6d76b40a3..8fd3a8627 100644
--- a/fsl/fslview/actions/__init__.py
+++ b/fsl/fslview/actions/__init__.py
@@ -55,12 +55,13 @@ class ActionButton(props.Button):
self.name = actionName
- props.Button.__init__(self,
- actionName,
- text=strings.actions[classType, actionName],
- callback=self.__onButton,
- setup=self.__setup,
- **kwargs)
+ props.Button.__init__(
+ self,
+ actionName,
+ text=strings.actions.get((classType, actionName), actionName),
+ callback=self.__onButton,
+ setup=self.__setup,
+ **kwargs)
def __setup(self, instance, parent, widget, *a):
diff --git a/fsl/fslview/colourmaps.py b/fsl/fslview/colourmaps.py
index c500932c1..2b3a6e583 100644
--- a/fsl/fslview/colourmaps.py
+++ b/fsl/fslview/colourmaps.py
@@ -712,6 +712,35 @@ def installLookupTable(lutName):
###############
+def _briconToScaleOffset(brightness, contrast, drange):
+ """Used by the :func:`briconToDisplayRange` and the :func:`applyBricon`
+ functions.
+
+ Calculates a scale and offset which can be used to transform a display
+ range of the given size so that the given brightness/contrast settings
+ are applied.
+ """
+
+ # The brightness is applied as a linear offset,
+ # with 0.5 equivalent to an offset of 0.0.
+ offset = (brightness * 2 - 1) * drange
+
+ # If the contrast lies between 0.0 and 0.5, it is
+ # applied to the colour as a linear scaling factor.
+ if contrast <= 0.5:
+ scale = contrast * 2
+
+ # If the contrast lies between 0.5 and 1, it
+ # is applied as an exponential scaling factor,
+ # so lower values (closer to 0.5) have less of
+ # an effect than higher values (closer to 1.0).
+ else:
+ scale = 20 * contrast ** 4 - 0.25
+
+ return scale, offset
+
+
+
def briconToDisplayRange(dataRange, brightness, contrast):
"""Converts the given brightness/contrast values to a display range,
given the data range.
@@ -733,20 +762,8 @@ def briconToDisplayRange(dataRange, brightness, contrast):
drange = dmax - dmin
dmid = dmin + 0.5 * drange
- # The brightness is applied as a linear offset,
- # with 0.5 equivalent to an offset of 0.0.
- offset = (brightness * 2 - 1) * drange
+ scale, offset = _briconToScaleOffset(brightness, contrast, drange)
- # If the contrast lies between 0.0 and 0.5, it is
- # applied to the colour as a linear scaling factor.
- scale = contrast * 2
-
- # If the contrast lies between 0.5 and 1, it
- # is applied as an exponential scaling factor,
- # so lower values (closer to 0.5) have less of
- # an effect than higher values (closer to 1.0).
- if contrast > 0.5:
- scale += np.exp((contrast - 0.5) * 6) - 1
# Calculate the new display range, keeping it
# centered in the middle of the data range
@@ -773,7 +790,7 @@ def displayRangeToBricon(dataRange, displayRange):
dmid = dmin + 0.5 * drange
# These are inversions of the equations in
- # the briconToDisplayRange function above,
+ # the briconToScaleOffset function above,
# which calculate the display ranges from
# the bricon offset/scale
offset = dlo + 0.5 * (dhi - dlo) - dmid
@@ -782,7 +799,7 @@ def displayRangeToBricon(dataRange, displayRange):
brightness = 0.5 * (offset / drange + 1)
if scale <= 1: contrast = scale / 2.0
- else: contrast = np.log(scale + 1) / 6.0 + 0.5
+ else: contrast = ((scale + 0.25) / 20.0) ** 0.25
brightness = 1.0 - brightness
contrast = 1.0 - contrast
@@ -805,26 +822,13 @@ def applyBricon(rgb, brightness, contrast):
:arg brightness: A brightness level in the range ``[0, 1]``.
- :arg contrast: A brightness level in the range ``[0, 1]``.
+ :arg contrast: A contrast level in the range ``[0, 1]``.
"""
rgb = np.array(rgb)
oneColour = len(rgb.shape) == 1
rgb = rgb.reshape(-1, rgb.shape[-1])
- # The brightness is applied as a linear offset,
- # with 0.5 equivalent to an offset of 0.0.
- offset = (brightness * 2 - 1)
-
- # If the contrast lies between 0.0 and 0.5, it is
- # applied to the colour as a linear scaling factor.
- scale = contrast * 2
-
- # If the contrast lies between 0.5 and 0.1, it
- # is applied as an exponential scaling factor,
- # so lower values (closer to 0.5) have less of
- # an effect than higher values (closer to 1.0).
- if (contrast > 0.5):
- scale += np.exp((contrast - 0.5) * 6) - 1
+ scale, offset = _briconToScaleOffset(brightness, contrast, 1)
# The contrast factor scales the existing colour
# range, but keeps the new range centred at 0.5.
diff --git a/fsl/fslview/displaycontext/volumeopts.py b/fsl/fslview/displaycontext/volumeopts.py
index c167454e2..928a92b96 100644
--- a/fsl/fslview/displaycontext/volumeopts.py
+++ b/fsl/fslview/displaycontext/volumeopts.py
@@ -430,7 +430,7 @@ class VolumeOpts(ImageOpts):
self.__toggleListeners(False)
# update bricon
- self.display.brightness = 100 - brightness * 100
- self.display.contrast = 100 - contrast * 100
+ self.display.brightness = brightness * 100
+ self.display.contrast = contrast * 100
self.__toggleListeners(True)
diff --git a/fsl/utils/fsldirdlg.py b/fsl/utils/fsldirdlg.py
index ba983379b..86fe646d3 100644
--- a/fsl/utils/fsldirdlg.py
+++ b/fsl/utils/fsldirdlg.py
@@ -62,11 +62,11 @@ class FSLDirDialog(wx.Dialog):
flag=wx.ALL | wx.CENTRE,
border=10,
proportion=1)
-
- self.__buttonSizer.Add((40, -1))
+ self.__buttonSizer.Add((20, -1))
self.__sizer.Add(self.__labelSizer, flag=wx.EXPAND, proportion=1)
self.__sizer.Add(self.__buttonSizer, flag=wx.EXPAND)
+ self.__sizer.Add((-1, 20))
self.SetSizer(self.__sizer)
self.Fit()
--
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