Info Pane and Images

The Info pane works with raster images of all kinds, and provides a limited capability to edit individual pixels in images.   Please review the Images topic before proceeding, especially the section of that topic titled Images are Stored as Tiles in Tables.     The Info pane provides so many capabilities that more than one topic is required.   See also the Info Pane topic for use with drawings and other components.

 

The main use of the Info pane with rasters is to see the heights or other values of pixels used in single-channel raster images, such as terrain elevation rasters.   Viewing and editing pixel values using the Info pane is a development tool and is not intended as a graphics editing tool.  

 

The ability to examine pixel values and to change them, is a useful tool when developing programs, scripts and queries for work with images.   Over time, Manifold will introduce user-friendly tools for pixel-level editing.

See Heights in a Terrain Elevation Raster

The Info pane allows us to see heights at specific locations in a terrain elevation raster.

 

 

We start with a raster image that has a single channel, which gives the height of the terrain at the pixel location.  The illustration above shows the terrain, thematically formatted and hill shaded.

 

 

Like all images in Manifold, this raster is stored as tiles, where each record in the associated table stores a tile that is 128 by 128 pixels in size.   

 

 

To see the height at a particular pixel, we Alt-click on the desired pixel.  For example, in the illustrated above we have alt-clicked upon the summit of a minor hill.

 

 

Alt-clicking a location in a raster image picks the tile that covers that location.  The square outline in the map shows the extents of the tile.   The Info pane automatically reports information for the tile in the Values tab.

 

 

To see the height of the context pixel (the pixel where we alt-clicked), we click on the Pixels tab.   The pixel will appear as a larger square in the map, and the cursor in the Info pane will be on the pixel.  We can see the height in that location is 444.

 

 

To see the height of a different pixel within the same tile we can simply click on that pixel.

 

 

The new pixel will appear as a larger square and the cursor in the Pixels list will jump to that pixel, scrolling the list as necessary to bring it into sight.

 

 

If we would like to see the height of a pixel outside the tile, we Alt-click the desired pixel.

 

 

As before, that picks the tile that contains that pixel.  

 

 

Clicking the Pixels tab shows the cursor on the picked pixel.   The height at that location is approximately 474.

Multichannel Images

The Info pane also works with multichannel images, which we can illustrate using an RGB image that has three channels.

 

 

We will use the sample Ginevra image, of a portrait painted by Leonardo da Vinci that is discussed in the Notes to the Example: Change the Contrast of an Image topic.

 

 

The image's table shows a typical Manifold table that stores tiles for images.   Each tile is 128 x 128 pixels in size, with each pixel containing three, unsigned integer values, a typical arrangement for what is commonly called an RGB image.   If we looked at the Style pane for this image we would see that, like almost all "RGB" images, the actual order of the numbers is BGR, that is blue, green and red values for the three channels.  The X and Y fields give the X and Y location of each tile in the matrix of tiles that makes up the image.

 

 

To bring the Info pane into play we Alt-click a location to pick the tile that contains pixels for that location.

 

 

The tile covering the Alt-clicked location is picked, appearing in blue outline with handles at the square corners.  If the view is zoomed out so the tile appears smaller, a larger box appears around the tile to make it easier to see where the tile is located.  This is helpful in busy visual displays of raster GIS data.     We can abandon picking a tile by pressing Esc, the Escape key.

 

The Info pane automatically opens, with the usual controls for the Values tab:

 

Click to pick the Previous tile or the Next tile.

Move only within selected tiles.  When enabled (only possible if there is a selection), constrains Previous and Next motion to the previous selected tile or to the next selected tile.

Zoom to the tile.  No effect if the zoom level already shows the tile in most of the display.

Update Record

Disabled in the Values tab, since all values are read-only.

 

The Values tab shows that we have Alt-clicked the tile at X location 12 and Y location 12 in the image.

 

 We can press the Next button to move the picked tile to the next tile.

 

 

The next tile is at X location 13 and Y location 12 in the image.   Just as with the use of Next and Previous in drawings, Manifold will try to avoid panning the image to bring Next and Previous tiles into view.

 

 We press the Previous button to move back to the originally picked tile.

 

 

We zoom in so the picked tile is larger.

 

Next, we click the Pixels tab.   

 

 

The Pixels tab shows the list of individual pixels within the tile, and the outline of the picked tile switches to edit mode with a larger edit handle.   

 

The Pixels tab provides the usual controls:

 

Click to pick the Previous tile or the Next tile.  In the Pixels tab, use of Previous or Next will switch back to the Values tab.

Move only within selected tiles.  When enabled (only possible if there is a selection), constrains Previous and Next motion to the previous selected tile or to the next selected tile.

Zoom to the tile.  No effect if the zoom level already shows the tile in most of the display.

<gray background>

Values shown with gray background are read-only and cannot be edited in the Values display.

<dotted outline>

The row with the dotted outline is the context row.  The pixel for the context row will be shown with a larger box in the image.

Pixel invisible (empty box) or visible (filled box).  Click  the on/off box to toggle the pixel off and on.  Applies to all selected pixels.   Pressing Update Record with a pixel OFF will result in that pixel being turned off for display, but then if it is turned on again the pixel channel values will be set to all zeros.

spacebar

Toggles the current pixel on/off.   Same as clicking the on/off box.

Click

Move the current cell to the clicked row, and display the corresponding vertex in the window using a larger blue preview box.

Ctrl-click

Select or deselect the row.

Shift-Ctrl-click

Select a swath of rows from that record to the next nearest (up or down) selected row, inclusive.

Double-click

Open the cell for editing.

Enter

Ctrl-Enter

Enter to open the current cell for editing, or double-click into a cell.  Enter also closes the cell for editing, leaving it in blue preview color until a Ctrl-Enter commits the change.  This is the same style of cell editing used in tables.

Ctrl-backspace

Abandon an edit.  Pressing the Esc key with the focus on the image also abandons any edits.

Arrow Keys

Move current cell up / down / left / right.

Home

Move current cell all the way to the left (layer names).

End

Move current cell all the way to the right (on/off box).

Ctrl-Home

Move current cell to the top layer.

Ctrl-End

Move current cell to the bottom layer (Background).

Page Up

Page Down

Move current cell up or down one page's worth.

Scroll bar

A vertical scroll bar appears when there are more layers than can fit into the display.   Scrolling the display does not move the current cell.

Scroll bar context menu

Right-clicking onto the scroll bar calls up a context menu:

 

  • Scroll Here - Drag the scroll bar handle to the spot right-clicked and scroll the display accordingly.

  • Top - Scroll the display to the top.

  • Bottom - Scroll the display to the bottom.

  • Page Up - Scroll the display up one page.

  • Page Down - Scroll the display down one page.

  • Scroll Up - Scroll the display up one row.

  • Scroll Down - Scroll the display down one row.

Update Record

Press to apply any changes.

 

For example, we can select a swath of pixels, which appear in red selection color.   We Ctrl-click the first row in the swath and then we Shift-Ctrl-click the last row in the swath, to select the two clicked rows and all rows in between.

 

 

Selecting a swath moves the row cursor to the last row in the swath, which becomes the context, or focus row.  The pixel for that row, the one with the table cursor on it in the list in the Info pane, appears with a larger box in the image window.

 

 

We double-click into the values cell for the first pixel, and we change the value to [0,0,255].   This sets the value of the Blue channel to 0, the value of the Green channel to 0, and the value of the Red channel to 255, setting a color for that pixel of full, bright red.   When we press Enter to accept the edit, that same value will be applied to all of the selected pixels., with the change for each pixel shown in blue provisional color.

 

We press Update Record to apply the change.

 

 

The lower left edge of the tile, that is, the region where the first fifteen pixels in the tile are located, shows those pixels now have been changed to red color.    

 

We click the Pixels tab to switch back to the Pixels tab (the display automatically switched to the Values tab when we pressed Update Record).

 

A red message icon appears in the lower tab to indicate a message is pending.  We click View - Messages in the main menu to see Manifold is offering to update intermediate levels, which we approve.  

 

 

When we updated intermediate levels, the system cleared the picked status of the tile.   We can clearly see the strip of red pixels caused by our editing.  

 

Let us now see what happens when we toggle the on/off boxes for pixels.

 

 

We Alt-click into the center of the display, to once again pick that same tile.

 

 

In the Pixels tab we select a large swath of pixels, from about one-third of the way down the list to all the way to the end of the list.   We click one of the on/off boxes.  That switches off all of the selected pixels.  

 

We press Update Record.

 

 

The selected pixels disappear, allowing the background to show through.   The visible/invisible status flag for those pixels has been set to invisible.

 

 

We can select the same swath of pixels again, by switching to the Pixels tab and scrolling through the list until we find the first row with a pixel turned off.  We Ctrl-click that row to select it.  The row cursor is on that row, and the pixel in the image window thus appears larger.   

 

 

We can then scroll to the bottom of the table and Shift-Ctrl-click the last row, to select all the rest of the rows in the desired swath.

 

 

We now once again click the on/off box for one of the selected pixels, thus setting all of the selected pixels on, that is, visible.  The pixels switch back on, but with color values of zero for all channels.   We press Update Record.  

 

 

The result is black color for all of the selected pixels.   Switching pixels off is a one-way operation, in that it loses whatever were the color values for those pixels.

The Context Pixel

When we pick a tile with an Alt-click, clicking any pixel in that tile in the image will make it the context row/pixel in the Pixels tab list of the Info pane, and will scroll the list to bring that row into view.

 

 

For example, in the illustrations above we have clicked a pixel approximately in the center of the picked tile.     We next will click on a pixel in the pupil of the image.

 

 

The new pixel becomes the context pixel and the list in the Info pane is scrolled to bring that pixel's row into view.   Conversely, if we click on a row in the table to make that row/pixel the context pixel, the context pixel will appear with a larger box in the image.

 

 

We have clicked on a row higher up in the list to make it the context pixel.  The new context pixel appears with a larger box, to the left of the pupil in the image.

 

Notes

Pixels are Visible or Invisible - Pixels in Manifold images can be visible or invisible, a flag used in addition to whatever an alpha channel specifies for the opacity of the pixel.  The on/off box in the Info pane for images toggles visible/invisible status.   Switching a pixel to off clears the value in the pixel.

 

See Also

Getting Started

 

User Interface Basics

 

Tables

 

Maps

 

Drawings

 

Editing Drawings

 

Snap Modes

 

Layer Opacity

 

Layers Pane

 

Select Pane

 

Style Pane

 

Transform Pane

 

Traverses

 

Example: Layers Tutorial - We take a tour of the Layers pane, learning how to manage layer display order, select layers, turn several layers on and off at the same time, alter opacity settings for one or more layers and how to change background color.

 

Example: Style Pane Quickstart - A tutorial introduction to using the Style pane to apply color, symbology, size and rotation to areas, lines and points in drawings.

 

Example: Edit Coordinates While Creating an Object - When creating an object in a map using a tool such as Create Area, right in the middle of the process we can edit coordinates in  the Info pane Coordinates tab.   This example shows the step by step process.

 

Example: Edit Attributes and Move a Point - We look at the attributes for a point in a drawing layer and edit one of the attributes using a more expanded Edit dialog.  We then move the point to a new location. Easy!

 

Example: Edit Attributes, Larger Text, IME for Asian Languages - A tour showing how to edit attributes in a drawing using the Info pane Values tab and the expanded Edit dialog, including advanced Unicode facilities and use of the built in Input Method Editor (IME) to input text in Japanese language.

 

Example: Create Parcels from Traverse Files - Traverse files using ESRI traverse file format are widely used by surveyors and government organizations in the US to define parcels and lines by describing a sequence of directions, distances and curves from a starting point.  Manifold automatically handles both tangent and non-tangent curves in ESRI traverse file format as well as the full variety of options used to specify angles, distances and curves.  This video shows how it's easy to create a parcel from a traverse file.

 

Videos

Manifold Future - Future Tour Part 1 - This video shows how to download and use a portable installation for Manifold Future.  The video also shows the Contents, pane, layers and layer opacity, one click use of data source favorites, using your own archival favorite and getting record values instantly.  If you are using Viewer or Radian Studio, download and use the Future version to get access to all these powerful new features.

 

Manifold Future - Future Tour Part 2 Editing - The video shows how to create new objects, how to add fields and vertices and move vertices around, how to edit existing objects and how to use simple selection methods to choose vertices to move together, including moving all objects.

 

Manifold Future - Future Tour Part 3 Editing - The editing tour continues with a look at how to create branched objects, including how to create areas with holes and islands, how to add branches to lines and how to add coordinates between vertices in existing objects.  We finish up by creating an area that traces over a pond in the Luxembourg Gardens in Paris using a Google satellite view, and then we add a hole to that area and two additional islands.

 

Manifold Future - Future Tour Part 4 Edit Attributes, Move a Point - We use Manifold Future to see how to view attributes of objects in drawings, including use of the new Edit dialog to view long, multi-paragraph text fields.  We edit fields and see how easy it is to preview edits and either accept them or abandon them. We switch to editing the geometry of objects in a drawing, viewing the coordinate locations and using mouse moves to reposition points. We edit the location of a point to correct an error in a drawing, using Google Satellite view to provide context for the correction.  Fast and easy, with previews all the way!

 

Manifold Future - Future Tour Part 5 Unicode Attributes and IME -  We take a tour through Manifold Future attribute editing, showing how to edit attributes in a drawing using the Info pane Values tab and the expanded Edit dialog, including advanced Unicode facilities and use of the built in Input Method Editor (IME) to input text in Japanese language.

 

Manifold Future - Future Tour Part 6 Cell Context Menu - A short video showing a fast and easy way to copy between cells in tables using the context menu.  Also... one step undo of pending changes,  setting the value of a cell to NULL and more. The context menu on cells is such a simple thing but it makes repetitive editing of tables much faster and easier.