Color / Colour Manipulation Preferences

Note: this help page in general uses the spelling "color". Depending on the branding of your SNAP application, elsewhere in your application the spelling may be "colour"

Overview

This page enables the user to modify the default settings for the Color Manipulation tool. Note: any changes made to the preferences will not be automatically updated until the application is either restarted or a new view window is opened.

To open the color manipulation preferences window select /Tools/Options/Color Manipulation from the main menu (Note: this may be located instead in File/Preferences on the Mac).

Palettes (Default)

These will be palettes to use with the associated field name.

• GRAY-SCALE: The color palette to use if the field "GRAY-SCALE" is selected.
• STANDARD: The color palette to use if the field "STANDARD" is selected. This by default is a rainbow spectrum type of palette.
• UNIVERSAL: The color palette to use if the field "UNIVERSAL" is selected. The universal palette field is intended for color-blind compliant palettes.
• ANOMALIES: The color palette to use if the field "ANOMALIES" is selected. This is intended but not limited to an anomaly type of palette.

Scheme (Default)

This is the default behavior when opening a new band or clicking on the reset button and a color scheme is not being applied.

• Enable - Use the following parameters as a default scheme when opening a band, otherwise use settings from the file reader. Note: this can be preempted by "Band Lookup Schemes" if "Use Band Lookup Schemes" is selected.
• Palette: - The palette to use for the scheme.
  • GRAY-SCALE: Uses the scheme as defined in the preferences field "GRAY-SCALE".
  • STANDARD: Uses the scheme as defined in the preferences field "STANDARD".
  • UNIVERSAL: Uses the scheme as defined in the preferences field "UNIVERSAL".
  • ANOMALIES: Uses the scheme as defined in the preferences field "ANOMALIES".
• Range: - The range to use.
  • From Data: Uses the range from the statistics of the data.
  • From Palette File : Uses the range as defined in the palette file.
• Log Scaling: - The log scaling to use for the scheme.
  • TRUE : Log scaling will be set to true.
  • FALSE : Log scaling will be set to false.
  • From Palette File : Uses the range as defined in the palette file. (Note cpt format files do not contain this field.)

Scheme (Band Lookup)

This is the behavior regarding applying color schemes when opening a new band or clicking on the reset button. If the "Apply Color Schemes Automatically" button is clicked and the bandname matches a regular expression scheme lookup (defined in the configuration file ~/.snap/auxdata/color_schemes/color_palette_schemes_lookup.xml) then a color scheme is applied (palette, range, log scaling). If no match is found, then the Default Scheme or the settings in the file reader are applied (see "Default Scheme" on this help page)

• Auto-apply: Automatically apply the band lookup color schemes when a band is opened or reset button is clicked.
• Palette: - The palette to use for the scheme.
  • From Scheme STANDARD: Uses the scheme from the configuration file defined by the parameter "STANDARD_FILENAME".
  • From Scheme UNIVERSAL: Uses the scheme from the configuration file defined by the parameter "UNIVERSAL_FILENAME". The universal palette field is intended for color-blind compliant palettes.
  • GRAY-SCALE: Uses the scheme as defined in the preferences field "GRAY-SCALE".
  • STANDARD: Uses the scheme as defined in the preferences field "STANDARD".
  • UNIVERSAL: Uses the scheme as defined in the preferences field "UNIVERSAL".
  • ANOMALIES: Uses the scheme as defined in the preferences field "ANOMALIES".
• Range: - The range to use for the scheme.
  • From Scheme: Uses the scheme from the configuration file defined by the parameters "MIN" and "MAX".
  • From Data: Uses the range from the statistics of the data.
  • From Palette File : Uses the range as defined in the palette file.
• Log Scaling: - The log scaling to use for the scheme.
  • From Scheme: Uses the log scaling from the configuration file defined by the parameter "LOG_SCALE".
  • From Palette File : Uses the range as defined in the palette file. (Note cpt format files do not contain this field.)
  • TRUE : Log scaling will be set to true.
  • FALSE : Log scaling will be set to false.

Percentile Options

Histogram-based range settings which get applied to palette.

• Percentile Default: Default palette range based on percentage of pixels in a band. This is used when scheme is disabled or when "From Data" is the specified behavior. This is also used with the "From Data" button.
• 1σ (68.27%) Button: Enables this button in the "sliders editor". This function adjusts the palette range to cover 1σ (68.27%) of all pixels in the band.  
• 2σ (95.45%) Button: Enables this button in the "sliders editor". This function adjusts the palette range to cover 2σ (95.45%) of all pixels in the band.  
• 3σ (99.73%) Button: Enables this button in the "sliders editor". This function adjusts the palette range to cover 3σ (99.73%) of all pixels in the band.  
• 95% Button: Enables this button in the "sliders editor". This function adjusts the palette range to cover 95% of all pixels in the band. This is retained as a legacy function.  
• 100% Button: Enables this button in the "sliders editor". This function adjusts the palette range to cover 100% of all pixels in the band.  

Scheme Selector Options

These are options to how and what is displayed in the color scheme selector in the "Basic editor". The pre-defined color schemes which appear in this selector are configured in the file: ~/.snap/auxdata/color_schemes/color_palette_schemes.xml.

• Verbose: - This is the longer verbose name of the color scheme as defined by the parameter "VERBOSE_NAME" in the configuration file.
• Sort: - This schemes are sorted alphabetically. If sort is false then the schemes appear in the same order as they are defined in the configuration file.
• Categorize: - This categorizes the display of the schemes in the selection into "Primary Schemes" and "Additional Schemes" as determined by the boolean parameter "PRIMARY" in the configuration file.
• Show Disabled: - Schemes could be disabled for various reasons such as the color palette of the scheme does not exist. If this field is checked then those schemes will be displayed in grey. If you click on the scheme then a dialog will indicate why the scheme is disabled.

Sliders Editor Options

• Histogram Zoom: - The histogram will by default be zoomed in to span the min/max range of the color palette (sliders).
• Show Information: - The statistical information overlay within the histogram plot window will be displayed by default.
• Vertical Zoom Buttons: Enables the vertical zoom buttons in the "sliders editor".    
• Information Button: Enables this button in the "sliders editor". This function enable display of statistical information overlaid in the histogram plot window..  

RGB Options

• Range Button (Min): - The value at which the preset range button sets the first (minimum) point of the color palette.  
• Range Button (Max): - The value at which the preset range button sets the last (maximum) point of the color palette.  

Restore

Restores all parameters within the Color Manipulation Preferences to the original default values.

Configuration of Preference Defaults

Many of the default values to the Color Manipulation Preferences are initialized internally to preset SNAP defaults. However, the above parameters may be initialized either for convenience of package defaults branding or for ease of presetting certain preference parameters without using the GUI to set the parameters. This is done within the snap.properties file which is in your home directory. The following are the property keys listed in the same order as the GUI preferences display with the SNAP default values.

# snap.color.manipulation.palette.default.gray.scale=gray_scale.cpd
# snap.color.manipulation.palette.default.standard=oceancolor_standard.cpd
# snap.color.manipulation.palette.default.universal=universal_bluered.cpd
# snap.color.manipulation.palette.default.anomalies=gradient_red_white_blue.cpd
# snap.color.manipulation.scheme.default.enable=false
# snap.color.manipulation.scheme.default.palette=GRAY-SCALE
# snap.color.manipulation.scheme.default.range=From Data
# snap.color.manipulation.scheme.default.log=FALSE
# snap.color.manipulation.scheme.band.lookup.auto.apply=false
# snap.color.manipulation.scheme.band.lookup.palette=From Scheme STANDARD
# snap.color.manipulation.scheme.band.lookup.range=From Scheme
# snap.color.manipulation.scheme.band.lookup.log=From Scheme
# snap.color.manipulation.percentile.value=92.0
# snap.color.manipulation.percentile.1.sigma.enable.button=false
# snap.color.manipulation.percentile.2.sigma.enable.button=true
# snap.color.manipulation.percentile.3.sigma.enable.button=true
# snap.color.manipulation.percentile.95.percent.enable.button=false
# snap.color.manipulation.percentile.100.percent.enable.button=true
# snap.color.manipulation.scheme.selector.verbose=false
# snap.color.manipulation.scheme.selector.sort=true
# snap.color.manipulation.scheme.selector.split=true
# snap.color.manipulation.scheme.selector.show.disabled=false
# snap.color.manipulation.sliders.zoom.in=true
# snap.color.manipulation.sliders.extra.info=true
# snap.color.manipulation.sliders.zoom.vertical.enable.buttons=true
# snap.color.manipulation.sliders.extra.info.enable.button=true
# snap.color.manipulation.rgb.button.min=0.0
# snap.color.manipulation.rgb.button.max=1.0

For SeaDAS these parameters are set as follows:

snap.context=seadas

seadas.color.manipulation.palette.default.standard=oceancolor_standard.cpd
seadas.color.manipulation.palette.default.universal=universal_bluered.cpd
seadas.color.manipulation.palette.default.gray.scale=gray_scale.cpd
seadas.color.manipulation.palette.default.anomalies=gradient_red_white_blue.cpd
seadas.color.manipulation.scheme.default.enable=true
seadas.color.manipulation.scheme.default.palette=GRAY-SCALE
seadas.color.manipulation.scheme.default.range=From Data
seadas.color.manipulation.scheme.default.log=FALSE
seadas.color.manipulation.scheme.band.lookup.auto.apply=true
seadas.color.manipulation.scheme.band.lookup.palette=STANDARD
seadas.color.manipulation.scheme.band.lookup.range=From Scheme
seadas.color.manipulation.scheme.band.lookup.log=From Scheme
seadas.color.manipulation.percentile.value=92.0
seadas.color.manipulation.percentile.100.percent.enable.button=true
seadas.color.manipulation.percentile.95.percent.enable.button=false
seadas.color.manipulation.percentile.1.sigma.enable.button=false
seadas.color.manipulation.percentile.2.sigma.enable.button=true
seadas.color.manipulation.percentile.3.sigma.enable.button=true
seadas.color.manipulation.scheme.selector.verbose=true
seadas.color.manipulation.scheme.selector.sort=true
seadas.color.manipulation.scheme.selector.split=true
seadas.color.manipulation.scheme.selector.show.disabled=false
seadas.color.manipulation.sliders.zoom.in=true
seadas.color.manipulation.sliders.extra.info=true
seadas.color.manipulation.sliders.zoom.vertical.enable.buttons=true
seadas.color.manipulation.sliders.extra.info.enable.button=true
seadas.color.manipulation.rgb.button.min=0.0
seadas.color.manipulation.rgb.button.max=1.0

If the above parameters do not exist in snap.properties or are commented out, then the SNAP package internal default values are used. Note that these are only default preference values, so if you set some of these parameters within the Preferences GUI, these values from the snap.properties file will be overridden by your GUI preferences. If you have modified the GUI preferences and wish to restore the values to the snap.properties file values then click "Reset To Defaults" in the Color Manipulation Preferences GUI.