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Editing Raster Geodata E D I T R A S T E R S Tutorial in TNTmips ® and TNTedit

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Page 1: Tutorial: Editing Raster Geodata - MicroImages, Inc. · Tutorial in TNTmips® and TNTedit™ page 2 Editing Raster Geodata Before Getting Started It may be difficult to identify the

Editing RasterGeodata

EDIT

RASTERS

Tutorial

in

TNTmips®

and TNTedit™

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page 2

Editing Raster Geodata

Before Getting Started

It may be difficult to identify the important points in some illustrations withouta color copy of this booklet. You can print or read this booklet in color fromMicroImages’ web site. The web site is also your source for the newesttutorial booklets on other topics. You can download an installation guide,sample data, and the latest version of TNTlite:

http://www.microimages.com

This booklet introduces techniques for creating, altering, and updating rastergeospatial objects in the Spatial Data Editor in TNTmips® and TNTedit™. Araster object contains a two-dimensional array of numeric cells of a common datatype. Each cell value can represent a geospatial variable (such as elevation, soiltype, crop type) or color information for display (numeric pixel color). This book-let introduces you to the basic raster editing tools. The Spatial Data Editor alsohas tools for editing your vector, CAD, database, TIN, and region geodata.

Prerequisite Skills This booklet assumes that you have completed the exercisesin the tutorials Displaying Geospatial Data and Navigating. Those exercisesintroduce essential skills and basic techniques that are not covered again here.Please consult those booklets and the TNTmips Reference Manual for any re-view you need.

Sample Data The exercises presented in this booklet use sample data that isdistributed with the TNT products. If you do not have access to a TNT productsCD, you can download the data from MicroImages’ web site. In particular, thisbooklet uses objects in the LANCSOIL and UNLPHOTO Project Files in the EDITRAST

data collection. Make a read-write copy of these files on your hard drive; youmay encounter problems if you work directly with the read-only sample data onthe CD-ROM.

More Documentation This booklet is intended only as an introduction to rasterediting in the Spatial Data Editor. Consult the TNT Reference Manual, whichincludes over 200 pages on the Spatial Data Editor, for more information.

TNTmips and TNTlite® TNTmips comes in two versions: the professional ver-sion and the free TNTlite version. This booklet refers to both versions as“TNTmips.” If you did not purchase the professional version (which requires asoftware license key), TNTmips operates in TNTlite mode, which limits objectsize.

The Spatial Data Editor is not available in TNTview or TNTatlas. All the exercisescan be completed in TNTlite using the sample geodata provided.

Keith Ghormley, 20 September 2004

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Editing Raster Geodata

The Spatial Data EditorThe TNT Spatial Data Editor (Edit / Spatial Data)offers a flexible, editing environment that can be usedfor simple one-object tasks or complex multi-layer,multi-object manipulations. You can have an objectin one layer, or a combination of read-only referencelayers, with other editable layers. You can have mul-tiple types of objects open at the same time, stackedin any front-to-back order.

Editing operations apply to the currently “active”layer. As you switch from layer to layer, the editingtools automatically change according to the datatype of the active layer (raster, vector, CAD, or TIN).

the ACTIVE layer has many ELEMENTS

one or more ELEMENTSmay be SELECTED

all map control automaticallyreconciled and maintained

one or more read-onlyREFERENCE layers

switch between one or moreEDITABLE layers

one editable layer is selectedas the ACTIVE layer

one SELECTED element maybe ACTIVE for editing operations

You may see editing tools like those in TNTmips inother software products, but the important thingabout the TNT Spatial Data Editor is the way youcan edit multiple geospatially related objects eas-ily and intuitively. You can concurrently edit projectmaterials of all types while TNT automatically re-tains and reconciles their map registrations. Thismeans that all the new objects you create can auto-matically derive their map registration from other lay-ers, so all of your project materials have a correctgeospatial relationship.

Newly created objects mayhave independently definedmap registration, or mapregistration derived fromanother layer in the editor.

A layer contains onegeospatial object: raster,vector, CAD, TIN, database,or complex layout. TNTautomatically reconciles themap registration and scaleof all layers.

The exercises on pages 4-13 take you through theprocess of marking anairphoto for a walking tourof part of a universitycampus. Pages 14-19introduce other rasterediting tools.

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Editing Raster Geodata

As an initial exercise, we will edit a ras-ter object that contains an airphoto im-age of a portion of a university cam-pus. We will mark sidewalks and build-ings to provide a color image map for acampus tour. Of course the edits wemake could alternatively be done with

the Spatial Data Editor in a CAD or vector overlay,but for these exercises we will edit the sample rasterobject itself.

Open the TNT Spatial Data Editor (Edit / SpatialData). Click the Open Object for Editing icon buttonand select the LITEDATA / EDITRAST / UNLPHOTO / UNL

raster object. UNL is an 8-bit 512 x 512 raster objectthat displays with a default color map. The displaycolors are all shades of gray, but the color map alsocontains a selection of bright colors that we will usefor editing operations.

Open UNL by clicking theOpen Object for Editing iconbutton.

In our first exercises, wewill use a single layer andedit one raster object. In alater exercise, we will editone raster object whileusing a second rasterobject in a reference layer.

Vocabulary:A Color Map (also “ColorTable”) assigns 8-bit datavalues (0-255) to discretedisplay colors. A ColorPalette presents all or partof a color map in a graphicinterface for color selectionand editing.

Open a Raster Object

STEPSclick the OpenObject for Editingicon button and selectthe LITEDATA / EDITRAST /UNLPHOTO / UNL rasterobject

The UNL raster objectcontains part of an airphotoof a university campus.

The view window displaysa temporary work raster,which you save into the UNL

raster object from time totime.

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Editing Raster Geodata

STEPSclick the Line buttonchange from Drawmode to Stretchmode

When you open a rasterobject for editing, theEditor opens the RasterTools window. The Ras-ter Tools window pre-sents a selection of toolsfor editing cells in a raster object. Since you want todraw lines first, click the Line tool in the top row.

The Editor opens a Line / Polygon Edit Controlsdialog. The Add End operation is the default selec-tion. In the Add End operation, each time you clickthe mouse, the Editor extends the prototype line byadding a new segment at the end. By contrast, theAdd Start operation is used to extend a prototypeline by adding segments to its initial point.

Change the drawing mode from Draw toStretch. The Stretch mode lets you see yournew line segment and drag the position ofits endpoint before you place it. For tracingoperations, this ability to move a segment to see thesurrounding photo image is very helpful. The Stretchmode also lets you hold down the Shift key to forcevertical and horizontal segments.

Remember, the Editor adds a line into a raster objectby replacing existing cell values with new valuesthat are mapped by the current color table to a se-lected color. Once a line is drawn into the raster, itcan no longer be selected and edited as a line.

The default operation is Add End.

Vocabulary:A prototype line is onethat you are creating andhave not yet added. Youcan modify a prototype line,but once you draw it intothe raster object, it can nolonger be selected andedited as a line.

The Line tool opensthe Line / Polygon EditControls window.

The AddEnd operationextends aprototype lineby adding segments to the end.

The Add Startoperation addssegments to aprototype line fromits beginning.

Select the Line Tool

"Add End"mode

"Add Start"mode

begin begin

22

33

11

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Editing Raster Geodata

STEPSclick on a red tile in thecolor paletteclick the [Cell...] pushbutton and examine theGet Raster Cell Valuedialogclick [Cancel] to closethe Get Raster CellValue dialogclick [Color...] to openthe Color Editor dialogclick [OK] to close theColor Editor dialogadjust the Width slider toset your line width to 4cells

In a color mapped display of an 8-bit raster object,each raster cell value is mapped to a discrete dis-play color. Since 8-bit data ranges from 0 to 255, an8-bit color palette has 256 colors.

Specify a drawing “color”numerically in the GetRaster Cell Value dialog.

Change the display color for the currently selectedediting value by clicking on a tile in the Palette tab ofthe Color Editor, or by adjusting component sliders inthe other tabbed panels.

Click on a tile in the colorpalette to choose a drawingcolor.

As you draw into a raster object, the cell valueschange to the numeric value that you are currentlyusing to draw. In the current exercise, we don’t caremuch how the cell values correspond to display col-ors, but in some applications, you may have reasonto want very specific values in the raster cells. TheEditor lets you select a drawing color from the colorpalette by clicking on a color, or you may specify anediting value numerically.

Change the line Width value to 4 cells so the side-walk lines will be thick enough to see easily.

... or typing in awidth value

change line width byadjusting the slider ...

Choose Line Color and Width

A selection of standardcolor palettes is availableon an option menu.

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Editing Raster Geodata

You are now ready to begin drawing red sidewalksfor the campus tour. Draw over the sidewalk fromthe library to the parking lot in the east central por-tion of the photo as illustrated. With the Line toolactive, each time you click the mouse, the Editoradds a prototype line segment. Your first click de-fines the starting point of the line, so choose thepoint where the sidewalk emerges from the east sideof the library. Then move the cursor and click on thecorner where the sidewalk turns south.

The Editor draws a pro-totype segment thatjoins your first two clickpoints. Click again,

STEPSlocate the sidewalk thatjoins the Library andparking lotclick the right mousebutton to add prototypeline segmentsdrag each new point toadjust the position ofthe new line segmentclick the right mousebutton to add the line

Cancel a prototype line that youdon’t want by pressing the Clear

button in the Edit Controls window.

The Editorshows thestarting point ofa prototypeline with a boxgraphic.

Each click adds a newprototype segment to the line.

The last segment ends with a circle graphic. Youcan drag the end by holding down the left mousebutton until the segment is where you want it.

When youfinish a

prototype line,draw it by

clicking theright mouse

button.

where the sidewalkmeets the parking lot.Since you are in stretchmode, you can drag out elastic segmentsby dragging the end of each new segmentto just the right spot. The prototype linedoes not show in the red color illustrateduntil you add the prototype by clicking theright mouse button.

Draw a Prototype Line

first click

second click

third click

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Editing Raster Geodata

Draw the sidewalk route as shown. Click the rightmouse button when you finish a prototype line todraw it into the raster object. The Editor draws theline in the selected color and width. (A later exercisedescribes techniques for deleting and correctingwhat you have drawn.)

At any time, you can zoom in to work at a highermagnification, and use the scroll bars to continueworking on a line that goes off the edge of the win-

dow. All of the standard dis-play tools are available in theView window.

The red sidewalk route that youhave drawn has changed the cellvalues in the photo image to 13,which is mapped to red displayvalues by the current colortable.

The Editor keeps the changesyou make in a temporary workraster. When you finish draw-ing the red sidewalk route as il-lustrated, select File / Save toupdate the UNL raster object.

The Spatial Data Editor also offers an autosave fea-ture. Select Preferences / Save from the Setup menuand specify how frequently you want your worksaved. Thereafter the Editor reminds you each timethe autosave interval elapses.

The Editor opens aVerify dialog to ask ifyou want to changethe UNL raster object,and again for eachautosave operation.

STEPSadd lines for thesidewalk routeillustratedselect File / Save towrite your edits into theUNL raster objectselect Setup / Prefer-ences and choose anAutosave interval in theSave panel of thePreferences dialog

Draw Lines into Raster

zoom and pan until youhave added lines acrossthe entire photo

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Editing Raster Geodata

Three main editing operations are available for pro-totype lines. Select the Insert, Drag, and Delete toolsin turn and practice changing the shape of a proto-type line. Each operation has particular usefulnessas you create a prototype line that follows a refer-ence feature in the image. As you click along a cur-vilinear path placing new segments, you may missthe feature by clicking to one side (delete that ver-tex) or by cutting a corner (insert a new vertex). Ex-periment with a prototype line until you have thefeel for each editing operation. You may practice ona prototype line and then cancel it if you wish.

Delete vertices where toomany errant mouse clickswandered off the feature.

Insert vertices where toofew mouse clicks did notconform to the complex shapeof the feature.

Drag vertices where themouse clicks missed thefeature.

It is especially important to edit prototype linescarefully as you edit a raster object. Once youdraw a line into a raster object, you cannot se-lect it as a line and reshape it the way you canreselect line elements in vector or CAD objects.As a later lesson shows (page 11), you can undoedits that you have made since the last File /Save operation, but the undo operation com-pletely erases your edits.

Practice on a prototype line.If you want to draw theresult into the UNL rasterobject, click the right mousebutton or [Add]. To discardthe prototype line, clickthe [Clear] button orjust select a differenttool.

Insert, Delete, and Drag

INSERT VERTEX• single mouse click• adds a new vertex at click point• one segment becomes two

DRAG VERTEX• drag with mouse• moves a vertex• number of segments does not change

DELETE VERTEX• single mouse click• removes vertex nearest to click point• two segments become one

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Editing Raster Geodata

The Polygon tool is slightly more complex than theLine tool, which you have been using. As with theline tool, a polygon’s initial point is indicated with abox, and the end of the last segment is indicated

with a circle. The new thing you see inthe polygon tool is a dashed line seg-ment (between the initial vertex and thelast vertex), which indicates how thepolygon would be closed were you tocomplete it by clicking the right mousebutton. All other aspects of the poly-gon tool are the same as the line tool.

For this exercise, you will outline cam-pus buildings. Select the Add Poly-gon tool and choose a yellow fill colorfrom the palette. Place a series of ver-

tices on the corners of a building by clicking the leftmouse button, and finish the polygon by clickingthe right mouse button. The Editor automaticallyfills the polygon with the drawing color.

You can edit a prototype polygon element the sameway you edit a prototype line. Use the insert, de-lete, and drag operations to reshape a prototypepolygon before you draw it into the raster object.

Draw Polygons

When you close a polygon,the Editor fills it with theselected drawing color orfill pattern.

STEPSselect the Add Polygon toolselect a yellow drawing colorclick the left mouse button to placea sequence of verticesclick the right mouse button to addthe polygonpractice tracing several campusbuildings as illustrated

Do not save these editsinto the UNL raster object.

The end of the last segmentis marked by a circle.

A dashed segmentshows how the polygonwould be closed.

The beginning of the firstsegment is marked by a box.

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Editing Raster Geodata

The Spatial Data Editor keeps the changes you makein a temporary work raster. You may undo drawingchanges you have made by restoring the work ras-ter from the UNL source raster object. Thus, as longas you have not saved your editing changes intothe UNL raster object(as on page 8), youcan undo your edits.However, once yousave your edits intothe UNL raster object,the restore operation has no effect.

The Restore from Source tool lets you draw a poly-gon on the image to define the area that containsedits that you want to undo. For this exercise, drawa polygon to enclose the buildings in the west andnorth portions of the photo as illustrated. An edit isremoved if it meets two conditions: (1) if you made itsince the last save and (2) if the edit falls inside therestore polygon.

The building polygons aregood candidates for re-doing. You probablynoticed that it is difficult totrace a regular-lookingbuilding shape from thisairphoto because of theperspective effect on thetall buildings. For bestresults, draw the roofoutline and then switch tothe Move Line operationand drag the prototypepolygon to the building’sfootprint position.

The Restore FromSource tool lets youundo edits made since thelast time you saved yourwork.

In the illustration, several yellowbuildings were included in the restorepolygon (illustrated in white), and theimage was restored from the UNL

source raster object. Observe thatsince the red sidewalks had previouslybeen saved into the UNL raster object(page 8), the Restore From Sourceoperation did not remove them.

Draw a polygon with the Restorefrom Source tool around an areayou want to restore and click the rightmouse button. The Editor copies cellvalues from the UNL raster object backinto the temporary work raster.

Restore, Undo/Redo

Observe that the Viewwindow also has a pair ofUndo/Redo buttons in the top corner.The Undo/Redo buttons let you stepback through a series of edits.

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Editing Raster Geodata

Add TextThe buildings on your campus tour map must benumbered so that visitors will be able to associatethem with a printed list that accompanies the map.In this exercise you will use the text tool to type anumber on each building.

When you click on the Text tool, the Editor opens aText Label Edit Controls dialog. Type the text youwant in the Text panel. Select a font and style in theStyle panel.

A text tool in the view shows where thetext will be drawn. Drag the baseline ofthe tool to position your label anywhereon the image. Drag the tool's "+" handle to resizethe text. Drag the "box" handles on the baseline tochange the angle of the text. When the text is theright size in the right place, click the Add push but-ton or the right mouse button to draw it.

STEPSselect the Text tooluse the left mousebutton to place the texttool crosshairs on ayellow buildingselect a black drawingcolor in both colorpalettestype text in the Textpanel of the Text LabelEdit Controls dialogchoose a font in theStyle panelresize the text tool forthe label size you wantclick [Add] to draw thetext at the text toolposition on the raster

The text you enterin the Text LabelEdit Controls dialogis added to the UNL

raster object withthe text tool.

Select black in bothcolor palettes.

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Editing Raster Geodata

Draw ShapesFinish numbering the buildings as illustrated. Inthis exercise you will add the final touches on yourcampus tour map: Start and End boxes.

Choose a green drawing color from the color paletteand select the solid rectangle drawing tool. Draw abox at the beginning and ending points of the touras illustrated. Then choose the Text tool and a blackdrawing color for the “start” and “end” text. Use theText tool and label the start and end boxes.

Experiment with the other shape drawing tools. TheEditor provides tools for outline or filled rectangles,circles, and ellipses. Create a prototype rectangleby dragging it out from its corner point. Prototypecircles and ellipses drag out from their centers; thenyou can resize them by dragging their edges.

As with lines and polygons, once you draw a rect-angle, circle, or ellipse shape into the image by click-ing the right mouse button, you cannot select andedit it as a shape. (Of course, you can erase it withUndo/Redo or theRestore from Sourceoperation, as de-scribed on page 11.)

STEPSclick on a green tile inthe color paletteselect the solidrectangle tooldraw a rectangle at thestart and end of the tourrouteclick on a black tile inthe color paletteclick on the Texttoolposition the text tool andtype in start and endlabels as illustratedsave (or discard)your work andremove the Airphotolayer from the View

Start and End boxescomplete yourcampus map image.

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Editing Raster Geodata

The Flood Fill tool fills an area with either a solidcolor or selected pattern. You can use it to replacea contiguous area of one solid color with another,or to fill an area that is enclosed with a continuousboundary of a solid color. The Flood fill tool wasdeveloped to help clean up scanned maps, remov-ing unwanted labels and notations as a preliminaryto automatic vectorization.

To select the fill tool, click the Flood Fill icon but-ton. The tool appears as a crosshair in a circle,which marks the point of the fill’s origin. Place thecrosshair with the left mouse button, and apply theflood operation with the right mouse button.

Three fill operations can be applied: Flood, Bound-ary, and Smart. Select the operation you want fromthe Point Edit Controls window, which opens whenyou select the tool. The illustrations below showthe results of each operation. NOTE: the Boundaryand Smart operations look for a contiguous bound-ary of a single solid color. You will not get satisfac-tory results if you apply the tool in an area that isnot so enclosed.

The Flood Fill toolworks in threedifferent modes and fills anarea with either a solidcolor or a selected pattern.

STEPScreate a new 16-bitRGB compositeraster object forpracticeuse the shape tools todraw a figure like theone illustratedpractice with the Flood,Boundary, and Smart filloperations

The fill tool works from thecolor at the point of origin.

FLOOD stops wherethe color of originstops.

BOUNDARY stops atthe border color.

SMART removesislands and stops atthe border color.

Flood Fill

Place the tool,then click GrabBorder Color toregister yourborder color.

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Editing Raster Geodata

Fill patterns let youdraw shapes that arefilled with transparentpatterns in order toidentify features in abackground image.For example, youmight draw a polygon around a wooded area in anairphoto and fill the polygon with a fill pattern oftree symbols. In the same way, a geologist mightdraw around a rock formation and assign a certaintype of rock symbol to an area according to the geo-logic survey data.

Fill patterns may be solid or they may be partiallytransparent. Choose a transparent pattern when youwant features in the image to show through. Youcan apply fill patterns with the shape drawing toolsand with the Smart Fill tool.

You can design any number of custom fill patternsfor special applications. Refer to the TNT ReferenceManual for instructions on using the pattern editor.

Select or create a fill pattern andpractice filling soil polygons.

STEPSopen the LITEDATA /EDITRAST / LANCSOIL /SHEET_45LITE rasterobject for practiceselect the polygontoolClick [Fill Pattern] andselect the STYLE

subobject underSHEET_45LITE

turn on the Fill Patterntoggle and click [FillPattern]select a transparentpatternpractice drawing filledpolygons, outlining soilpolygons

Fill Patterns

Turn on the Fill Pattern toggle andclick [Fill Pattern] to select a pattern.

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The Editor supports Cut, Copy, and Paste opera-tions so that you can duplicate part of an image.Selecting the Cut, Copy, Paste tool opens the BoxEdit Controls window. The basic procedure is:

Press the Copy icon button in the Box Edit Con-trols windowUse the left mouse button to draw an elastic boxaround the part of the image you want to copyClick the right mouse button to register the copyPress the Paste icon button in the Box Edit Con-trols windowUse the left mouse button to drag the paste box to itstarget locationApply the paste operation by clicking the right mousebutton

You can rotate and resample the copy by selectingPaste Resampled instead of Paste. When PasteResampled is selected, you can resize the target elas-tic box by dragging its edges, and rotate it by hold-ing down the Shift key as you drag a corner.

The Cut, Copy, Pastetool opens the Box

Edit Controls window soyou can duplicate part of animage.

COPY

PASTE

PASTE RESAMPLED

Part of the image is selected with the Copy box.

The Paste box and Paste Resampled box isused to make copies of different sizes andaspects. The rotation effect can be used torotate labels for map features such as rivers.(Although many labeling tasks are more suitedto vector and CAD objects.)

Cut, Copy, and Paste

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Using a Reference Layer

Create a soil mask in theSOILMASK raster object bypainting over the CrC soilpolygons in the SHEET_45LITE

reference raster object.

You can edit one rasterusing another raster as areference layer.

The Null Cells Transparenttoggle lets a referenceraster object be seenbehind the raster object youare editing.

One of the most powerful features of the SpatialData Editor is its ability to let you work with multiplelayers. Often, your multi-layer editing will use a ras-ter object as the backdrop and you will edit CAD orvector objects as overlays. (Refer tothe tutorial booklet Editing VectorGeodata) But multi-layer editing hasits uses with raster objects, too. Youcan edit a raster object over a rasterobject if the raster object in the edit-ing layer has null values defined.Turn on the Null Cells Transparenttoggle in the Display Controls dia-log, and then the reference raster be-low will show through the null cells.

As an exercise, edit a soil polygonmask raster object:

add LITEDATA / EDITRAST / LANCSOIL / SHEET_45LITE as areference layeropen LITEDATA / EDITRAST / LANCSOIL / SOILMASK as theraster object to editset Null Cells Transparent in the Options tab of theRaster Layer Controls dialog for SOILMASK

use the paintbrush orthe polygon tool to paintover the CrC soil polygons

The finished SOILMASK rasterobject could be used as a pro-cessing raster in raster analy-sis combinations, or for refer-ence and display.

Setting a transpar-ency value lets yousee the referenceimage behind thefeatures you draw.

If you set atransparency

value, you mayneed to pressredraw to see thepolygon with thetransparencyeffect.

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Editing Raster Geodata

Recall that a raster object is logically a two-dimen-sional array of numbers. In 8-bit raster objects(which have a data range of 0 to 255), the number ineach cell is mapped to a display color by the color

map or contrast table.

When you use the raster editing tools,you are changing the numeric values ofthe raster cells, and thereby changing thecolor of the image. The Spatial Data Edi-tor also lets you change cell values di-rectly by entering numbers from the key-board. Click the Numeric Edit tool buttonto open the Raster Inspection window.You can click the mouse cursor on theimage to see the cell values for that loca-tion, or you can type line and column val-

ues into the Raster Inspection window to specifyprecisely which part of the raster you want to view.

Numeric editing would be slow and tedious for largeextent features, but it gives you very precise con-trol for specific locations and individual cells.

Numeric Editing

Use the Point Edit Controlsdialog to specify precise mapcoordinates for the point youwant to see in the RasterInspection window. Type in thecoordinates you want and click[Edit] to jump to that position inthe image.

The Numeric Edit toolopens the Raster

Inspection and Point EditControls windows.

The Raster Inspectionwindow shows the cellvalues for the part of theimage at the tool’s crosshairand lets you type in a newcell value.

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The Paint tool opens the Paint Brush window,which offers a selection of brush shapes and

sizes. You can also create acustom brush shape (per-haps in the shape of a logoor special symbol) by click-ing the Brush push button.Paint with the current brushshape and color by draggingthe brush cursor over the image with the left mousebutton.

The Grab Color tool presents a crosshair thatyou place by clicking the left mouse button.

Use the keyboard arrow keys for fine adjustmentof the crosshair position, and then click [Grab Color]to make the cell color at the crosshair position thenew drawing color. You can also enter map coordi-nates to position the crosshair.

The Grid tool lets you draw an elastic boxthat defines the region for a grid. A Box Edit

Controls window lets you specify the number ofgrid divisions and whether the grid lines have alinear or logarithmic distribution.

You can define and select custom Line Patterns inthe same way that you define and select custom fillpatterns (see page 15). Apply linepatterns with the Line tool, any ofthe outline shape tools, and with theGrid tool.

The Spatial Data Editor offers manymore features than this booklet hasintroduced. Be sure to look at thetutorials Editing Vector Geodata,Editing CAD Geodata, and EditingTIN Geodata for more information.

Other Tools

Page 20: Tutorial: Editing Raster Geodata - MicroImages, Inc. · Tutorial in TNTmips® and TNTedit™ page 2 Editing Raster Geodata Before Getting Started It may be difficult to identify the

page 20

Editing Raster GeodataAdvanced Software for Geospatial Analysis EDIT

RASTERS

Voice: (402)477-9554www.microimages.com

MicroImages, Inc. publishes a complete line of professional software for advanced geospatial datavisualization, analysis, and publishing. Contact us or visit our web site for detailed productinformation.TNTmips TNTmips is a professional system for fully integrated GIS, image analysis,

CAD, TIN, desktop cartography, and geospatial database management.TNTedit TNTedit provides interactive tools to create, georeference, and edit vector, image,

CAD, TIN, and relational database project materials in a wide variety of formats.TNTview TNTview has the same powerful display features as TNTmips and is perfect for

those who do not need the technical processing and preparation features of TNTmips.TNTatlas TNTatlas lets you publish and distribute your spatial project materials on CD-

ROM at low cost. TNTatlas CDs can be used on any popular computing platform.TNTserver TNTserver lets you publish TNTatlases on the Internet or on your intranet.

Navigate through geodata atlases with your web browser and the TNTclient Java applet.TNTlite TNTlite is a free version of TNTmips for students and professionals with small

projects. You can download TNTlite from MicroImages’ web site, or you can orderTNTlite on CD-ROM.

active elements .................................... 3active layer .......................................... 3Add End mode .................................... 5Add Start mode ................................... 5autosave .............................................. 8cell values .......................................... 18color editor .......................................... 6color map ............................................ 4cut, copy, paste ................................ 16delete vertex ........................................ 9drag vertex ........................................... 9draw mode .......................................... 5drawing color ...................................... 6editable layer ....................................... 3fill patterns ....................................... 15flood fill ............................................ 14grab color .......................................... 19grid tool ............................................. 19insert vertex ........................................ 9

layer .................................................... 3line patterns ...................................... 19line segments ....................................... 7line tool ............................................... 5null transparency .............................. 17numeric editing .................................. 18Open Object for Editing ..................... 4paint brush ........................................ 19polygon tool ..................................... 10prototype line ................................. 5, 7reference layer ............................... 3, 17restore from source ........................... 11selected elements ................................ 3shape tools ........................................ 13smart fill ............................................ 14stretch mode ....................................... 5text tool ............................................. 12transparency ..................................... 17undo/redo .......................................... 11

MicroImages, Inc.¤

Index