PDS Imaging Node
Display Dictionary

• Hierarchical Listing of Classes
• Alphabetical Listing of Classes
• Alphabetical Listing of Attributes
• Class Definitions
• Attribute Dictionary

This dictionary describes how to display Array data on a display device.

• Display_Settings

• Local_Internal_Reference

• comment
• local_identifier_reference
• local_reference_type

• Display_Direction

• comment
• horizontal_display_axis
• horizontal_display_direction
• vertical_display_axis
• vertical_display_direction

• Color_Display_Settings

• color_display_axis
• comment
• red_channel_band
• green_channel_band
• blue_channel_band

• Movie_Display_Settings

• time_display_axis
• comment
• frame_rate
• loop_flag
• loop_count
• loop_delay
• loop_back_and_forth_flag

• Color_Display_Settings
• Display_Direction
• Display_Settings
• Movie_Display_Settings

• blue_channel_band
• color_display_axis
• comment
• frame_rate
• green_channel_band
• horizontal_display_axis
• horizontal_display_direction
• local_identifier_reference
• local_reference_type
• loop_back_and_forth_flag
• loop_count
• loop_delay
• loop_flag
• red_channel_band
• time_display_axis
• vertical_display_axis
• vertical_display_direction

Color_Display_Settings

Class Description: The Color_Display_Settings class provides guidance to data users on how to display a multi-banded Array object on a color-capable display device.

	Entity	Card	Value/Class
Hierarchy	pds:Tagged_NonDigital_Object
	. Color_Display_Settings
Subclasses	none
Attributes	color_display_axis	1
	comment	0..1
	red_channel_band	1
	green_channel_band	1
	blue_channel_band	1
Associations	none

Display_Direction

Class Description: The Display_Direction class specifies how two of the dimensions of an Array object should be displayed in the vertical (line) and horizontal (sample) dimensions of a display device.

	Entity	Card	Value/Class
Hierarchy	pds:Tagged_NonDigital_Object
	. Display_Direction
Subclasses	none
Attributes	comment	0..1
	horizontal_display_axis	1
	horizontal_display_direction	1	Left to Right Right to Left
	vertical_display_axis	1
	vertical_display_direction	1	Top to Bottom Bottom to Top
Associations	none

Display_Settings

Class Description: The Display_Settings class contains one or more classes describing how data should be displayed on a display device.

	Entity	Card	Value/Class
Hierarchy	pds:Tagged_NonDigital_Object
	. Display_Settings
Subclasses	none
Attributes	none
Associations	has_Local_Internal_Reference	1	Local_Internal_Reference
	has_Display_Direction	1	Display_Direction
	has_Color_Display_Settings	0..1	Color_Display_Settings
	has_Movie_Display_Settings	0..1	Movie_Display_Settings

Local_Internal_Reference

Class Description: The Local_Internal_Reference class is used to cross-reference other Description Objects in a PDS4 label.

	Entity	Card	Value/Class
Hierarchy	pds:Tagged_NonDigital_Object
	. Local_Internal_Reference
Subclasses	none
Attributes	comment	0..1
	local_identifier_reference	1
	local_reference_type	1
Associations	none

Movie_Display_Settings

Class Description: The Movie_Display_Settings class provides default values for the display of a multi-banded Array using a software application capable of displaying video content.

	Entity	Card	Value/Class
Hierarchy	pds:Tagged_NonDigital_Object
	. Movie_Display_Settings
Subclasses	none
Attributes	time_display_axis	1
	comment	0..1
	frame_rate	0..1
	loop_flag	0..1	true false
	loop_count	0..1
	loop_delay	0..1
	loop_back_and_forth_flag	0..1	true false
Associations	none

blue_channel_band

The blue_channel_band attribute identifies the number of the band, along the band axis, that should be loaded, by default, into the blue channel of a display device. The first band along the band axis has band number 1.

Type: ASCII_Integer
Minimum Value: 1
Nillable: false
Steward: img
Name Space Id: disp


color_display_axis

The color_display_axis attribute identifies, by name, the axis of an Array (or Array subclass) that is intended to be displayed in the color dimension of a display device. I.e., bands from this dimension will be loaded into the red, green, and blue bands of the display device. The value of this attribute must match the value of one, and only one, axis_name attribute in an Axis_Array class of the associated Array.

Type: ASCII_Short_String_Collapsed
Nillable: false
Steward: img
Name Space Id: disp


comment

The comment attribute is a free form text string providing additional details related to default display parameters.

Type: ASCII_Text_Preserved
Nillable: false
Steward: img
Name Space Id: disp


frame_rate

The frame_rate attribute indicates the number of still pictures (or frames) that should be displayed per unit of time in a video. Note this is NOT necessarily the same as the rate at which the images were acquired.

Type: ASCII_Real
Unit of Measure Type: Units_of_Frame_Rate
Minimum Value: 1.0
Specified Units: frames/s
Nillable: false
Steward: img
Name Space Id: disp


green_channel_band

The green_channel_band attribute identifies the number of the band, along the band axis, that should be loaded, by default, into the green channel of a display device. The first band along the band axis has band number 1.

Type: ASCII_Integer
Minimum Value: 1
Nillable: false
Steward: img
Name Space Id: disp


horizontal_display_axis

The horizontal_display_axis attribute identifies, by name, the axis of an Array (or Array subclass) that is intended to be displayed in the horizontal or "sample" dimension on a display device. The value of this attribute must match the value of one, and only one, axis_name attribute in an Axis_Array class of the associated Array.

Type: ASCII_Short_String_Collapsed
Nillable: false
Steward: img
Name Space Id: disp


horizontal_display_direction

The horizontal_display_direction attribute specifies the direction across the screen of a display device that data along the horizontal axis of an Array is supposed to be displayed.

Type: ASCII_Short_String_Collapsed
Minimum Characters: 13
Maximum Characters: 13
Nillable: false
Steward: img
Name Space Id: disp


Values:
- Left to Right - The lowest indexed element along an array axis should be displayed at the left edge of a display device and elements with higher indices should be displayed further to the right. Note that this is the standard display direction for most major image formats.
- Right to Left - The lowest indexed element along an array axis should be displayed at the right edge of a display device and elements with higher indices should be displayed further to the left. Note that virtually no image display formats use this display direction. Use this only when deliberately mirroring the image around the vertical axis.


local_identifier_reference

The local_identifier_reference attribute provides a character string which is used to reference a uniquely identified object within the label.

Type: ASCII_Short_String_Collapsed
Minimum Characters: 1
Maximum Characters: 127
Nillable: false
Steward: pds
Name Space Id: pds


local_reference_type

The local_reference_type attribute provides the name of the local association.

Type: ASCII_Short_String_Collapsed
Minimum Characters: 1
Maximum Characters: 127
Nillable: false
Steward: pds
Name Space Id: pds


loop_back_and_forth_flag

The loop_back_and_forth_flag attribute specifies whether or not a movie should only be "looped" or played repeatedly in the forward direction, or whether it should be played forward followed by played in reverse, iteratively.

Type: ASCII_Boolean
Nillable: false
Steward: img
Name Space Id: disp


Values:
- true - When looping, the movie should be played in the forward direction, followed by the reverse direction, iteratively.
- false - When looping, the movie should only be played in the forward direction. This is the default behavior.


loop_count

The loop_count attribute specifies the number of times a movie should be "looped" or replayed before stopping.

Type: ASCII_Integer
Minimum Value: 1
Nillable: false
Steward: img
Name Space Id: disp


loop_delay

The loop_delay attribute specifies the amount of time to pause between "loops" or repeated playbacks of a movie.

Type: ASCII_Real
Unit of Measure Type: Units_of_Time
Minimum Value: 0.0
Specified Units: s
Nillable: false
Steward: img
Name Space Id: disp


loop_flag

The loop_flag attribute specifies whether or not a movie object should be played repeatedly without prompting from the user.

Type: ASCII_Boolean
Nillable: false
Steward: img
Name Space Id: disp


Values:
- true - The movie should be "looped" or played repeatedly.
- false - The movie should be not be "looped" or played repeatedly.


red_channel_band

The red_channel_band attribute identifies the number of the band, along the band axis, that should be loaded, by default, into the red channel of a display device. The first band along the band axis has band number 1.

Type: ASCII_Integer
Minimum Value: 1
Nillable: false
Steward: img
Name Space Id: disp


time_display_axis

The time_display_axis attribute identifies, by name, the axis of an Array (or Array subclass), the bands of which are intended to be displayed sequentially in time on a display device. The frame_rate attribute, if present, provides the rate at which these bands are to be displayed.

Type: ASCII_Short_String_Collapsed
Nillable: false
Steward: img
Name Space Id: disp


vertical_display_axis

The vertical_display_axis attribute identifies, by name, the axis of an Array (or Array subclass) that is intended to be displayed in the vertical or "line" dimension on a display device. The value of this attribute must match the value of one, and only one, axis_name attribute in an Axis_Array class of the associated Array.

Type: ASCII_Short_String_Collapsed
Nillable: false
Steward: img
Name Space Id: disp


vertical_display_direction

The vertical_display_direction attribute specifies the direction along the screen of a display device that data along the vertical axis of an Array is supposed to be displayed.

Type: ASCII_Short_String_Collapsed
Minimum Characters: 13
Maximum Characters: 13
Nillable: false
Steward: img
Name Space Id: disp


Values:
- Top to Bottom - The lowest indexed element along an array axis should be displayed at the top edge of a display device and elements with higher indices should be displayed lower down. This is the display direction typically used for VICAR formatted data.
- Bottom to Top - The lowest indexed element along an array axis should be displayed at the bottom edge of a display device and elements with higher indices should be displayed higher up. This is the display direction typically used for FITS formatted data.