Easy Trace Group

Conventionally, all changes and improvements may be divided into six categories:

• New format of Easy Trace PRO project;
• Relief digitizing;
• Digitizing of polygonal coverages;
• Digitizing of 1:500 maps;
• Space imagery decoding;
• Miscellaneous.

Some old tools and utilities were improved of course, and some very promising new utilities remained incomplete because of urgency and diversity of our recent projects, and thus were not included into this release. But we shall surely return to them later.

 

10.x - new format of Easy Trace PRO project

Format: ET-project has become a solid data file without the separate folder of attributive tables. The format remains closed and we do not plan to open it.

Speed: The speed of project opening and saving increased drastically - these operations have become several times quicker. It is particularly evident at work with big projects and composite coverages consisting of tens of sheets.

Limitations: Some rudiments of the previous format’s limitations still persist (8190 vertices per line at the maximum, bridges between the inner and the outer polygon contours) but their elimination is the matter of time. It will take a revision of a substantial code volume but these limitations are not inherent to the format any more.

Compatibility: Using of the new format does not require any additional actions. You just open your project after installation of the new ET version, the program converts it quickly, and… that’s all. Your project will be saved in the new format by default. Also, you may use old projects as prototypes unrestrictedly, and all new projects will inherit there data structure, operating environment settings, custom tools, strategies of tracers and utilities, etc.

Backward compatibility: Even if you have only one renewed package in your working group, it should become “the leader”. One working place is quite enough to prepare images for new projects, digitize them automatically, and fulfill primary vector cleaning and correction before transfer to other operators. It is also reasonable to use it for assembling of the full vector coverage, line joining at sheet boundaries, data control and optimization. All these procedures have become much quicker in the new version.

It takes only one additional operation called Compose Project to transfer the project into a previous version. The command opens a dialog box where you select the format 7.x-9.x and specify the folder for project saving. At loading of an old project, the program asks, whether you want to convert it into 10.x format. Just answer “No”.

 

Imagery digitizing

Interactive tracing of polygonal areas' borders (NEW!)

We were thinking about interactive digitizing of space photos for a long time as they are just another kind of rasters for the tracer tool, or a set of rasters in case of the multispectral imagery. Even more so since in practice most users work with orthogonally transformed photos it the form of RGB images. The worst of it is that synthesized, transformed, and color-corrected images have a “thinned out” palette of color tints resembling degradation of "true" colors in maps “overcompressed” by JPEG-coding. Histograms of such images look like a comb with every third or fourth tooth remained only...

The human brain is a wonder. For example, we can read a text with a great share of letters changed for figures or put in wrong places. The same is true for the image - it may be quite distinct visually even if its source palette is torn to shreds. Never mind – here are the boundaries! Well, the problem is to understand what and how do we see.

Anyway, we taught the tracer “to run” along the boundaries though color and brightness differentials are badly blurred by the “thinned out” palette in space photos. As usually, the tool was developed in the course of the next project – farmland inventory (according to Rosreestr, more than 40% of farmlands have not yet been registered in the cadastre).

The current scheme of interactive digitizing of polygonal objects’ borders in the imagery is the following

• Select Curvilinear Tracer, then open the Tracing Parameters dialog box and create a new strategy with the Imagery Areas tracing type (Once! Later you will only use it);
• Select the Automatic tracing mode;
• Left click inside the area you want to outline – the tracer shows the recognized contour;
• Keep Ctrl pressed and rotate the mouse wheel to enlarge or contract the contour;
• Right click or Esc to fix the result.

Additionally you may keep Shift pressed and rotate the mouse wheel to clean cavities in the boundary. Wheel rotation with Alt pressed helps to change the degree of line smoothing (optimization). In this case the program suggests you to save the new optimization parameters to the current strategy for subsequent use. It was usually difficult for the beginners to select line form optimization parameters in the digital form, but everything is simple now: rotate the wheel => estimate the result => save the found parameters for future use.

If some boundaries of the polygon are hardly visible or represented by straight lines, you may form this part of the contour manually, then start the automatic mode, click any point inside the area, and then proceed as described above.

The resulting contour will certainly need some rectification with the Vector Eraser and Camber Editor tools, but on the whole digitization of farmlands became about two times quicker according to our operators’ estimation. Time saving is most noticeable for polygons of curved complex shape.

See video for an example of tool application:

Note also that the usual interactive tracer is long able to recognize country dirt roads rather well.

Split-screen vector displaying above a multispectral imagery (updating)

Manual decoding of farmland boundaries is usually based on a set of space imageries. It comprises a true-color photo plus an infrared one or another synthesized imagery revealing object boundaries. There may be more than two photos (rasters) – at seasonal surveying, etc.

The first thing that comes to mind is raster stacking applying the option of transparent image displaying. It works well enough for example at map superposition on the photo but gives terrible results for the case of several imageries. It is much better to split the working window in 2 or 4 parts and display the vector in them synchronously above different rasters (or even better display these windows on different screens).

Strictly speaking, ET has this displaying mode for a long time, but only now it has become possible to see the current rubber band line or the running semiautomatic tracer in all the windows at the same time. Previously, you had either change the current window all the time to check the fitness or bear with delayed line displaying in additional (not current) windows.

Transparent Images mode

One more displaying version is added to the Transparent Images mode. It makes “transparent” only pixels lighter than the user-specified threshold and thus allows color or grey-scale map superposition above a space- or aerophoto without quality lost of the latter. In other words, only lines and fillings darker than the specified threshold will be displayed above the imagery but the dirty grey background of the map will remain completely transparent. The option is accessible for all images differing from black-and-white ones (as their black background is transparent by default).

Cursor tracing mode (updating)

The cursor tracing mode (continuous line forming directly by the move of mouse cursor) proved to be most popular at imagery decoding, but it requires a sure hand if you do not want to record the trembling. Integrated line smoothing is essential for this tool. This mechanism was revised so that even I can draw nice lines now!

See video for an example of tool application in this mode:

Digitizing of polygonal coverages

Filtering Connected Trash utility (NEW!)

Typically, AUTOMATIZED digitizing (I do not like the term "automatic" as it is applicable to a limited class of tasks only) consists of several operations:

• Extraction, cleaning, and may be thinning of the subject image;
• Image digitizing, vector cleaning, merging and correction of vector elements;
• Assembling, shape improvement, classification of vector objects and attribute data input.

In data-loaded maps, deletion of vector “rubbish” (inevitably generated by digitizing) takes up to 90% of working time. I would like to emphasize for skeptics right away: vector cleaning and improvement is SEVERAL TIMES FASTER than successive accurate tracing of one line after another by any method.

“Rubbish” deletion is most laborious at digitizing of hand-made materials, such as soil maps in our recent project. They contained very thick lines, numerous hand-written inscriptions and graphical symbols, and were painted with color pencils.

Great line thickness is not blessing by any means. Thick lines in shabby materials turn into downright dirt with numerous cavities and gaps. The only remedy in that case is repeated diffusion and contrast enhancement. Unfortunately the same operations cause also conglutination of text, conventional symbols, and useful lines. Further processing generates complex vector conglomerates adhered to polygon boundaries.

The Raw Line Filtering utility can not delete such conglomerates; so, we have developed the specialized Filtering Connected Trash utility for this task. As text recognition is completely impossible in such line tangles, the utility recognizes them on the base of some typical features. These are high compactness (big line length in the conglomerate at small size of the encompassing rectangle), small length of the object, a big number of elements in it, and the fact of contiguity to something resembling a polygon boundary (i.e. a long line with a slight bend).

Below is an example of images the utility was developed for. These are soil rating maps – the source image and the black subject layer extracted from it. The extraction took a rather long sequence of commands controlled by the Compound tool. The Local Contrast Enhancement utility was included into this sequence for extraction of dark-brown boundaries.

Parameter setting for the Filtering Connected Trash utility looks somewhat frightening but there specifying causes no problem as and samples of conglomerates to be deleted may be selected directly on the screen in the Preview mode. You just specify the layer you want to clean, click Reset, and start sampling selection.

Brightness of the source vector decreases to simplify the control, but selected conglomerates become on the contrary highlighted. The lower group of parameters in the dialog box limits conglomerate growth to avoid their "creeping" on the polygon boundaries. Prior line smoothing improves reliability of conglomerate recognition. It does not affect the source vector data.

The utility “kills” some useful vector segments of course, but they are short and thus can be easily restored by the Breakup Joining and Topology Correction (Snap line ends… option) utilities.

Search for Lines (updating)

An alternative way to detect polygon boundaries in a very dirty image or separate relief elements from contour lines is "tracing of the vector". Unlike other tracing tools, the Search for Lines tracer "runs" along dense vector lines generated by the Autotrace Lines utility rather than lines in the image. The tool exists already for a long time, but now it was updated and got a new ability: in the Cursor Tracking path routing method the tool leaves the current raw line and transfers to its continuation specified manually without unnecessary questions.

The case in point is not simple gaps in lines – the tool crosses them successfully from the very beginning. The situation is more difficult and should be considered in detail. Dirty images with line color hardly differing from the background (e.g., half-erased pencil lines on an old 1:500 map or polygon boundaries on a map colored manually, see the figure above) require a special processing. It necessary comprises a combination of Diffusion and Unsharp Mask (sharpness improvement) steps. The first operation helps to assemble line remnants together and the second separates the line from the background.

A critical parameter at sharpness improvement is the Unsharp Mask Radius. It is responsible for the decision "what exactly should be improved?" It means that the optimal Radius value depends on the line width. In dirty images the width becomes several times more at line crosses, and the program interprets these "bulbs" as the background (there are no brightness jumps within the mask radius!), sharpness improvement does not happen, and one of the lines (the thinnest and the weakest usually) "falls off".

The Local Contrast Enhancement utility is particularly effective at extraction of weak lines, but this same tool causes line "falling off" most often. After digitization, the junctions may be restored with the Topology Correction utility (Snap line ends… option) but vectorized inscriptions, topographic symbols and other rubbish objects will inevitably stick to these lines on overstuffed maps. That is why tracing of vector lines is a reasonable choice for them. Not all lines “fall off” of course – it happens when the lines are very thin near the node, almost cut off already, but there may be a lot of them in some images.

Now, the tracer can jump across a ruined node to the line continuation rather than search for a bypass passage via other branches outgoing from the node.

This new feature proved to be very useful at tracing of relief elements (cliffs, ravines, rock outcrops, index lines on rocks), boundaries of shaded area (not filled but just shaded with diagonal or another hatch), contours of building with a big number of adjoining boundaries and communication lines, etc. For example, in the soil map project it saved us a lot of time at tracing of long ravines. Not only boundaries of these narrow polygons were actually contiguous – their dark-brown color hardly differed from the color of soil type polygons’ boundaries.

Autodetect Point Symbols utility (updating)

This revision allowed us to delete numerous topographical symbols from soil map images. The utility is primarily intended for recognition of the symbols and exact positioning of their insertion points. At that, the symbols may consist of several disconnected elements, differ in size and inclination. In our particular case, symbol recognition was not required (they were coded by attributes of soil type polygons), but we used the utility as it can optionally erase recognized symbols from the image.

Maximal size of recognizable objects was increased together with improvement of recognition exactness and interface of object selection. As a result, we managed to get rid not of toposymbols only but also of long strokes in dashed lines representing dirt roads. The lines had the same color as polygon boundaries and crossed them in an arbitrary way.

It took us only 7-10 minutes to clean the image from several tens of thousands of “rubbish” objects. The time was spent to specify patterns of the objects to be deleted (the maps were drawn manually by different persons and the symbols had little more than the meaning in common).

Mask patterns are now connected with any specified layer rather than the current one. It is enough to leave the Layer field in table of patterns empty and the objects will be recognized “to nowhere”, i.e. just deleted from the image.

Combined image processing (NEW!)

If your computer is not too slow (even better if it has a modern graphic card on a NVIDIA processor), you may estimate future results of a series of image processing operations at once. Even the simplest basic sequences of actions like Diffusion – Contrast Enhancement – Conversion to the Monochrome Color Mode leave students of our courses asking questions about “right” parameter values suitable for all occasions. And they simply do not exist!!!

All settings depend on image resolution, condition, compression algorithm and degree, amount of represented information, colors that should be separated from each other, and so on. But there are rather clear approaches to selection of parameter values – line extraction should generate neither gaps nor adhesion, and should separate objects of different colors as well as possible.

It is actually impossible to tell a priori how strongly this particular image should be blurred to course collapse of cavities in lines, disappearance of line “branches”, and deletion of dirt from the background after contrast enhancement without loss of thin lines. As a rule, it takes several trials to get a decent result, even more so for our low-quality materials.

It is well worth the effort anyway, as digitizing of a soundly extracted image is several TIMES (not percents) faster.

But now everything has become much easier – you may find optimal settings by the rule of thumb. Take the standard strategy directly from the Compound tool or make up a set of operations relying on our video-lesson or the corresponding post from our forum, and start parameter selection. How? Depending on the final result – it is visible at once now.

Several tries will be sufficient to understand what the effect of different parameters in every operation is. For the beginning, it may be useful to move sliders of the tools from one stop to another. (It is better to use copies of the basic strategy for learning – just change the name and click Save).

Besides, the tool itself contains a guide book of a kind, with pairs of figures (before/after), the strategy used to get the result, description and explanation of operations in the strategy, and the corresponding source image fragment for your own experiments.

 

Relief Digitizing

Processing of Contour Clumps utility (NEW!)

We have never seen so many mistakes and contour lines discontinued at bottlenecks as on the General Staff’s 1:50,000 maps of foreign territories. On the whole, they looked like a shoddy piece of work: "Why to try? There are no our tanks abroad any more!". But the performance specification provided for line joining, and so we did.

A utility for equidistant laying of discontinued contours was developed. It also marks endpoints of lines that can not be joined as they belong to different contours. This utility significantly accelerates digitizing of complex relief with long zones of missing contours.

The principle of operation is based on tracking of corridors formed by index (thick) contours. Additionally, the utility uses linear objects and boundaries of areal relief elements that may break contours similar to the sheet border.

Line Width Recovery utility (NEW!)

Raw data for the Line Width Recovery utility consist of the vector layer with autotracing results and the initial thick-line black-and-white image (not thinned!), which was ultimately the starting point of digitization.

Generally speaking, we recommend to save two black-and-white images in the project always –the Thick image generated at subject layer extraction and its Thin copy created by the Image Thinning operation. Automatic line tracing uses the Thin image, whereas Thick is necessary for recognition of topologic symbols and, from now on, also for recovery of information about line thickness.

Click the Preview button, and the utility will gather statistics about width of raster lines underlying vector lines of the specified layer. The task is rather difficult as the width of individual lines varies in a wide range because of line agglutinations, crosses, and gaps.

After calculation, the utility displays the histogram of line distribution by width. Simultaneously, it marks with user-specified colors line parts that correspond to the currently specified width intervals. Move sliders of the histogram to define width intervals of thick and thin lines more exactly. You may zoom and scroll the working window during the execution to estimate correctness of the intervals.

This new utility works well together with the previous one. Drawing of discontinued intermediate contour lines is based on tracking of corridors formed by index contours, and the source image is useful for automatic recognition of the latter after digitization.

The Apply button assigns thickness values to all lines that got into one of the specified width intervals. The value is saved as a special attribute $Thickness (just as the attribute $Z provided for elevation). The lines get the average width value of the interval they belong to. The $Thickness attribute value of lines having thickness that didn’t get into one of the specified intervals is zero.

Now, the lines with different values of the $Thickness attribute may be isolated to different layers, or you may select them and assign the usual Contour Type attribute. Use the View Attributes dialog box or the Object Filter command from the Group Editor submenu.

Automatic recovery of line width is quite suitable for work acceleration but not perfect. There will be manual correction of course, particularly of short contour segments between relief elements, near sheet borders, etc.

Not also, that final line width equalizes at subject layer extraction from a dirty image with the help of Diffusion + Unsharp Mask operations, as it starts to depend on mask radius. And it happened to us to apply this pair of operations up to 3 times in a row.

Assign elevations to 3D Lines utility (NEW!)

The utility calculates elevation of vertices in 3D polylines (ravines, river lines, etc.) on the base of Z-values of relief contours, which these objects cross. It also marks 3D-polylines that do not cross any contour. The mark looks like a segment between the line start and end points, similar to other utilities of Z assign/check.

 

Digitizing of 1:500 maps

Transform Classifier utility (NEW!)

Lack of official data format standards in Russian electronic cartography causes repeatedly “cash disbursement” in connection with transfer to the next “finally right” geoinformational system. At that, previously created vector data get scuttled sometimes and digitizing starts from the beginning.

It is reasonable quite often. Early waves of "wild digitizing" generated a great amount of data that hold no water in the sense exactness and topology correctness. Good riddance! But there is no rule without an exception, and a lot of quite adequate data should be converted to another format. This is not a trivial task at all...

As usually, we developed the utility when the task had to be fulfilled “by yesterday”. In the middle of project execution, the Customer informed us that a decision had been made to change the target system. It was something like jumping from one train to another. On-the-run, and with the luggage. We had to change the data presentation form, and thus data classifying. The only (but significant) advantage was the fact that we prepared the data by ourselves.

Fortunately, everything was no so bad. The classifiers differed in structure and object attributes of course, but the new one didn’t require additional "decorations" in the form of so called auxiliary (service) objects and other arrows, strokes, daggers, etc.

We had to fulfill two operations:

• Object ascription to layers. It was necessary to either change the layer of objects or distribute them among several layers in accordance with attributive characteristics.
• Modification of attributes. This task was much more complex and comprised two stages. Identical attributive characteristics often have distinct names even in different variants of the same GIS classifier, not to mention different target systems. Renaming was the first stage, but not the worst one. Not attributes’ names only required change but also the ranges of their allowed values (domains), and often without one-to-one relationship between the old and the new GIS.

All these modifications should be done simultaneously of course, in the process of conversion – it is impossible to assemble data in a new format after partial destruction of the old one. We didn’t develop an original controlling mechanism for conversion rule tables, but applied commonly used Excel, which already has it.

You may also specify the output format of converted data through a ET project-prototype (if you have one of course). In that case, data representation, topologic rules, strategies of tools and utilities in your new project will be taken from the prototype. Beside, the type and format of attributive fields will be specified exactly. Without the prototype, the program tries to determine them on its own.

It goes without saying that the prototype should strictly correspond to the new classifier, into which you convert the data. At any discrepancy between the prototype and the rules of conversion, the utility will inform you about an error in the corresponding line.

Examples of projects before and after classifier conversion, as well as the Excel table of conversion rules and a descriptive file may be found here.

Checkup and Correction of Communications utility, М 1:500 (NEW!)

Digitizing of communication networks requires correct ascription of point objects - manholes to different layers depending on the layers of corresponding communication lines. It is difficult to check the correspondence visually, even on the base of attributive data. Besides, layer specifying for all these points is tiresome in itself and generates many mistakes, even more so due to low quality of old and shabby 1:500 maps.

On the other hand, it is easy to check correctness of the communication network and manholes connected with these communications automatically. The new utility Checkup and Correction of Communications will do everything instead of you if correspondence of communication and manhole layers is univocal.

The utility functions as follows:

• Checks the structure of communication lines (belonging of all elements of every network to the same layer, free line terminations, etc.)
• Checks and corrects distribution of manholes previously attributed to corresponding layers;
  
• Searches for other errors - "hanging" manholes, crosses of different-type communications with vertex forming, etc.
• Attributes all other manholes (recognized previously by the Autodetect Circles utility) to corresponding layers;
  

Some situations will be supplied with error marks as usually. Quick navigation between the errors is supported by the customary for Easy Trace hot keys F (next) and V (previous). Correct the mistakes and run the utility again until you get the message "No errors found".

Other new and updated utilities

Compose Project utility (NEW!)

Note, that we use the term “project” in two ways - to denote either an order received from the Customer, or a unite of operator’s work.

Lately, we come across projects with very big images with ever increasing frequency. These may be soil maps, or space imageries, or projects comprising groups of 1:500 sheets. Urgency of the orders forces us to organize just-in-time work, starting digitizing immediately on receiving of the next portion of images (and without any trial project of course – “there is no time to explain, start doing!”).

The only reasonable and right approach in this situation is conveyor-like line processing of materials. It may comprise many stages, but four at least are compulsory: image preparing – digitizing – attribute data input – integration. At that, processing of hydrographical objects, relief, and vegetation in topographic maps is separated. This implies high-level requirements to mobility of working units (projects consisting of one or several sheets) to provide easy and reliable exchange between operators.

High-speed network and a data server with common folders for images and folders for storage of working units would be an ideal decision. In practice, real executors never have time (and money!) enough to organize the work in this way and have to put up with data reshuffle between operators.

The new Compose Project utility is developed for saving of all parts of the project to one folder without omissions. It is useful in the case of home-working freelancers, for project transfer between subdivisions, etc.

It is enough to specify a new project name and path for project assembling. Additionally, you may select the Easy Trace format version to be used at saving – it may be necessary for interaction with operators who apply earlier versions of the software.

Recovery Points utility (NEW!)

Deep modifications of vector data by means of integrated utilities consist one of Easy Trace advantages. There are utilities for vector filtering, object recognition, line form optimization, topology correction, line merging at boundaries, topology optimization, etc. These powerful tools execute thousands and even tens of thousands of object modifications simultaneously. And as all powerful things, they require careful and competent use. A big truck can do a lot, but it can also crush a small car in passing...

Now you have a “time machine” for safety use of utilities – intermediate saving of the project before a potentially dangerous operation. It creates a backup copy, and you can return to it if the results are unsatisfactory.

A backup copy is the most reliable way to protect your data. Of course, ET has deep “Undo” for almost all operations (except deletion of vector layers) but it works only during the current session. Just imagine that you left for a coffee-break without project saving and somebody (just for a minute!) took your protection key…No chance for “Undo” after it.

Make control points of project recovery every time you are not sure in results, just to avoid any unexpected situation. It is simple now - the Recovery Points utility enables creation of several points and selection of any such point for returning to a previous project state.

Autodetect Circles utility

Some new features are added to the utility; its interface is improved and simplified:

• The Apply special processing for maps on scale 1:500 option is added for automatic recognition of topologic symbols represented by circles with additional lines inside. These are usually symbols of inspection chambers (manholes). The symbols may be badly damaged (torn pieces of circles) or adhered to other objects in our low-quality maps, and the search took much time.
• The Color field is added to the table of patterns. Every pattern has its color now used both for displaying of histogram sliders and recognized circles in the working window of your project.
• The Move up / down buttons are provided for the pattern table management. Pattern move increases / decreases its priority at recognition.
• The Stretch / Fewer buttons are added to the histogram for exact specification of permissible intervals of circle diameters. For example, the diameter distribution peak of one circle type may be stretched to the full size of the histogram.

Raw Line Filtering utility

The following changes are made in the basic Raw Line Filtering utility intended for preliminary processing of results of automatic digitizing:

1. Recognition of the Spikes artifact type is added for recovery of “collapsed” extremities of narrow polygons (e.g., ravines). The option substitutes such “branches” for smooth contour continuations and thus restores the initial form. Specifying of convergence angle for spike shoulders enables accurate separation of “collapsed” polygons from usual T-joints of vector lines;
2. Recognition of the Y-Joints artifact type is added for Y-like nodes of the third degree. These artifacts appear as a rule at bottlenecks due to adhesion of left-off contours to neighboring lines, i.e. the Y-Joint is one half of the Adhesion artifact. The utility cuts out these nodes, and the freed lines can be afterwards joined correctly with the Breakup Joining utility or (more reliably!) with the new Processing of Contour Clumps utility;
3. Both maximal and minimal value can be specified now for the Winding parameter of Strokes. This updating is useful for deletion of dashed lines drawn above polygonal objects (e.g., dirt roads crossing soil-type polygons). Previously, only the lower limit was available.
4. The Width of raster lines… parameter, which controls the “depth” of correction should be specified now separately for every tracing strategy. It helps to find the shape of added lines more exactly at Branch deletion and correction of T-Joints, as well as the size of the line part to be cut out from Y-Joints.
5. The Stretch option is deleted from parameters of the Branches artifact type as the new type Strokes is added.

Breakup Joining utility

Preview of the utility application results is added. Now, even beginners can select parameter values most appropriate to the specific material on the first try as results become visible before execution of the operation.

• The algorithm of short segment processing is improved. Previously, the utility didn’t perform winding test of segments considered short. For example, you could not use segments up to 9 pixels long as points (without directions) and ignore badly winding segments shorter that 7 pixels at the same time. Now, the program performs both tests and selects the strongest reaction (up to deletion).
• An individual button is provided now for specifying of the breakup joining area.
• УThe utility may be run without preview and even without opening its dialog box and receiving the final message if you assign it a hot key. It is convenient at gradual “untangling” of a complex polygonal material with numerous irrelevant lines and inscriptions. Deletion of the next portion of “rubbish” with Vector Eraser and execution of the utility enables you to “reveal” the next area of the polygonal coverage.

Autodetect Dot Lines utility

Dot lines on topographical maps are easy for automatic recognition (the size and shape of dots are stable, and the distance between them is constant and rather small). Situation with departmental maps (forest estimation records, etc.) is quite different - line representation is all in a tumble. One have to specify a much wider range of possible dot-to-dot distances, many points are indistinguishable from rubbish objects and can not be used at line recovery. The following updates were made for processing of such materials:

• Selection of barrier layers for dot lines is transferred to the first step of the utility. It helps to avoid long-distance breakup joinings across lines - barriers. Beside, contour closing near the barriers is forbidden (as it hinders line snapping at the next step of the utility);
• Additional filtering of ambiguous triangles is added to the primary chain binding step.

Cut ut Subprojects

The Crop the images to the frame option is added. If selected, the program not only saves all images of the current subproject to the subproject folder but also crops them along the frame. The Copy images to subproject folder option becomes unavailable as they will be saved to this folder automatically.

Attribute Tables dialog box

The search for objects with the same attributes is added. To find the object with similar values of an attribute, type the exclamation mark in the filter cell of the corresponding column.

Autodetect Topo-Symbols utility

Unlike the Autodetect Point Symbols utility, this one uses raster “spots” rather than their vector contours. It makes autodetection low-sensitivity to symbol “adhesions” to other objects. On the other hand, the utility has difficulties with recognition of symbols with variable size and inclination differing from the selected pattern.

As the utility analyzes the image, symbol recognition in grey-scale and color images is added. Specifying of symbol search masks remained unchanged.

Buffer Zone Generation utility

Utility improvement enables specifying of buffer zone width independently of the project scale. Maximal possible width is 200 mm of the paper (200 m on 1:1000 maps and 20 000 m on 1:100 000 maps).

 

Digitizing and editing tools

Through command Snap Line End

It is hardly reasonable to "drag" all free line ends at once with the Topology Correction utility at clearance of autotracing results. On the other hand, manual snapping takes too much time, as there may be a lot of hanging nodes in dashed lines or lines left-off near objects and near the sheet frame.

Now, you may snap any hanging node to the nearest line with automatic selection of the snapping point or specify the direction explicitly. Place the cursor of ANY editing tool BETWEEN the line termination and the line you want to snap it to in the first case or THE OTHER SIDE of the line in the second case, and press the hot key B.

This video demonstrates the operation:

Shears

Cropping algorithm is optimized and parallelized. Cropping along the contour has become 25 times faster on a 4-core computer.

The Shears tool crops a compound vector coverage along the border of one or several closed contours, with optional deletion of objects’ parts falling inside or outside these contours. Any closed polyline may be selected as the cropping frame.

Corrector

The list of situations that the tool can now process is actually the same as the list of artifacts in the Raw Line Filtering utility. But unlike the utility, the tool enables the operator to specify individual artifacts and correction methods directly. Corrector should be applied after line filtering to solve the problems the utility didn’t cope with.

The tool functions in the following way:

1. Highlights lines that potentially need processing at cursor approaching to an artifact;
2. Suggests the most probable alteration when you click the left button;
3. If the tool didn’t “guess right”, it cyclically changes possible corrections of the situation at next left clicks;
4. Rotation of the mouse wheel changes correction parameters – size of the line part to be deleted or straighten, bend radius, etc.
5. Right click to apply the selected correction method.

Additional setting of preferable processing methods is available in the tool’s dialog box (the “hammer” button in the Parameters Bar).

Editor

1. The Equidistant merging mode . Mode has extended abilities of the Editor tool at polyline processing. The mode is intended for generation of contour lines’ missing parts through bottlenecks. Line form correction is not required actually if the restored parts have no sharp bends.
   
   Note: a shift of already existing contours may be necessary for laying of missing intermediate contour lines with equal line-to-line distance in the corridor formed by index lines. The simpliest way of the work is the following:
   
   
   • Dissect the line beam with Vector Eraser to separate lines neighboring with left-off ones from their continuations;
   • Move the cut-off line parts with the Shift/Resize Polylines tool and merge them with their continuations again;
   • Execute equidistant merging of left-off contours inside the resulting widened corridor.
     
     
2. At merging of line terminations adjacent to other polylines, the program looks for the shortest way via existing objects within the working window and uses it as the closing segment, similar the approach utilized in the Autoclose mode of semiautomatic digitizing. Elsewhere, closing by a line segment or a smooth arc will be fulfilled depending on Shift key pressing.
   
   
3. At object attribute editing, an automatic increment may be specified if the attribute type is Integer. Click in the Auto check-box of this attribute in the Object Attributes dialog box until the "+1" symbol appears. After that, attribute value will automatically increase by one at selection of the next object if it has no an assigned attribute value yet or remain unchanged if it has.

 

Semiautomatic digitizing

It is not required any more to press the hot key (Z) or switch to the red scissors mode of the Editor for line part deletion if the tracer has run too far along the line in the semiautomatic mode. Just click the point in the current line you want to make the final one. This way of line part deletion is also available in the manual tracing mode.

Band Polygon tool

Band polygons may be formed for several polylines at once. Select the lines with the Group Editor, and then click any of them with the tool’s cursor. To unselect the lines without polygon forming, click somewhere outside the group.

The tool may be used to generate band polygons (buffer zones) along a set of polylines selected with the Object Filter of the Group Editor in accordance with the specified criteria. Forming of band polygons up to 200 m wide is also added.

Shift / Resize Polylines tool

The Units button is added to the Parameters Bar of the tool. It enables you to select the units for specifying of polyline shift or polygon widening (contracting). These are pixels, project units, or mm of the paper original. The updating is made for manual generation of buffer zones along objects.

Group Editor

Now, the program shows the total line length and polygon area in the tool’s Parameters Bar at selection of several objects. The area may be measured in the project units or in other units (e.g., hectares) depending on settings made in the Project Properties dialog box.

 

Image editing tools

Image Thinning

The utility has got a dialog box where you may select the source image and the way of processing. The resulting thinned image may be saved with a new name to remain the source one intact. The thinned copy becomes a new image layer if the source image is already linked to a project. Optionally, the image may be binarized, otherwise a pseudo-grey image will be generated where brightness depends on source line thickness. It may be used for automatic digitizing directly to get lines that already have thickness values. Unfortunately, Mask Filtering is inaccessible for such images.

Execution of the Image Thinning is optimized and parallelized. As a result, the operation has become 7-10 times faster.

Image Cleaning

A button in the Tools tool bar is provided now for Image Cleaning. Preview of cleaning results is added; undoubtedly, it simplifies selection of the operation parameters.

 

Other improvements

Hot Keys dialog box

The Utilities category of hot keys is added. These hot keys enable you to start execution of Breakup Joining, Raw Line Filtering, Topology Correction, Topology Checkup and other utilities quickly, bypassing the menu. They are quite helpful as clearance and correction of automatic tracing results requires repeated use of the utilities.

System Settings, page Images

The Select the compression method automatically new option is added to the General page of the Images group in the dialog box. When on, the program selects compression method at image saving automatically, when off – uses the method applied in the source image. It is convenient at processing of rasters compressed with ineffective algorithms.

Export to DWG (AutoCAD)

An existing DWG drawing may be opened for writing at export now (previously, the program just overwrote it). The Clear existing layers option is provided for this purpose. When on, vector objects and images will be deleted from the DWG layer of the same name (if exists). When off, exported data will be added to existing objects.

Object Attributes dialog box

Attribute value selection from the drop-down list (e.g., domain of possible values) is simplified. Start typing the value and the list will be scrolled automatically to the corresponding record.

Project Properties dialog box

The Use alternative area units option is added to the Options page of the dialog box. Area may be specified now in hectares, areas, sq. m, and sq. km at a criterion-based object selection with the Group Editor and in the View Attributes dialog box. At selection of closed polylines or polygons with the Editor, the area will be also displayed in the units you have specified.

Merging of adjoining polygons by the double click has become optional (see Project -> Project Properties -> View and Editing -> Options) as it often hindered editing of vector objects. The double click in ET is the Polyline Joining through command first of all; it is available from almost all editing tools. Polygon merging by the double click is off by default now. Usually, it is reasonable to switch it on for quick joining of polygonal coverages along the borders of map sheets digitized separately.

The Fill polygons at scrolling option is deleted. The operating speed of modern computers and graphic cards is quite sufficient for permanent displaying of fillings.

Blocks

Comment: blocks are widely in use in Easy Trace PRO as a convenient mean of point symbol representation. Initially, they got to the program from ACAD and had only the “classical use”, but later proved to be indispensable for quick project setup to various classifiers. Most GISes storage conventional signs in non-documented inner formats and it is problematic to extract them and use at map digitizing.

Block creation in ET is simple – draw it somewhere on the project field, select all elements with the Group Editor and declare them a block. Later it may be connected with the attribute-based displaying of point objects. As a result, the objects take the form of the block and the corresponding pictogram appears in the list of possible attribute values. Besides, you may use the blocks as in ACAD, up to final block disintegration into elements at export to the target GIS.

The Table of Project Blocks is updated:

• The program determines default block layers now reasoning from information about blocks already inserted in the project;
• The standard layer tree is provided for selection of the block layer instead of the list;
• The "Delete", "Delete All" and other buttons are substituted for a Toolbar duplicated by the context menu;
• A field at the foot of the table is added for descriptions of the dialog box controls and elements.

Z parameters (contour elevations) dialog box

Optionally, you may now allow omissions of intermediate contours. Z-value of existing lines will be calculated on the base of the distance from neighboring index contours. Previously, the situation caused the error message "Intermediate contour is missing!". Z input in maps with contours missing at bottlenecks has become much easier.

 

Debugging and small alterations

• The bug is corrected: loading of empty table of blocks in some cases.
  
  
• Add Image/Relink Image: at image registration with reference file/metadata use, the program checks if the new raster “lays” well, i.e., if its size/scale/insertion point fit project parameters. If they are too much out of proportion, a warning appears about possible loss of accuracy.
  
  
• The bug is corrected in time accounting: the new project inherited duration of working sessions in the prototype at prototype-based creation. It caused overestimation of working time. Time correction is also added for previously executed projects – the program deletes all sessions started before project creation at loading.
  
  
• The bug is corrected in the Project Information utility: incorrect line length in the XLS report. The data lost the decimal delimiter at export to XLS and the length became three orders greater (at dec=3).
  
  
• Export to Panorama GIS: existence of the table of point objects’ attributes is not required any more for vector layer export to Panorama.
  
  
• The bug is corrected: cursor traces remained at two-screen work after cursor moving outside the working window.
  
  
• Restored: the possibility to select “Another color” in the elevation scale of Z parameters.
  
  
• Export to AutoCAD is corrected: the program exported all objects to the same layer even if the “Create separate layers for objects..." option was on. Export of line types is provided (only adding, without overwriting of existing ones).
  
  
• The bug is corrected: export / import of line types didn’t function if the delimiter of the fractional part differed from '.' (point).
  
  
• Imagery loading is corrected: the program didn’t load png-files and palette ones (Yandex maps). “Interpolation” option is now working at transformation.
  
  
• The bug is corrected: attribute structure change in the opened Table of Attributes could cause errors and strange shifts in the table until you opened it again or changed the layer in it.
  
  
• The bug is corrected: compound processing resulted in an empty image if it started with the Brightness/Contrast operation.
  
  
• Execution of the Z Checkup utility is accelerated.
  
  
• The bug is corrected at reading of some types of TIFF images.
  
  
• The bug is corrected: saving of subject layer extraction parameters in the Compound tool required pervious saving in the color-separating sub-tool itself. In general, everything was rather complicated. Now strategies of color separation and the sub-tool current settings are independent.
  
  
• The bug is corrected: it was impossible to start the Create Subprojects utility if even one of all possible layers was not selected.
  
  
• The limitation of Undo buffer is removed (it was 2 GB, insufficient for very big images).
  
  
• The limitation is removed at attribute editing: it was 30 characters at the maximum.
  
  
• The Topology Editor and the Cleaning mode do not interact with view modes any more – they do not start the Show vertices mode forcedly.
  
  
• Undo for vector data is restricted to 1 Gb – something like a protection from overfilling at processing of giant projects.
  
  
• The bug is corrected: 15-s pauses and memory leak at quick repetition of Undo/Redo operations when the snapping mode is on.
  
  
• The bug is corrected in image tools with Preview: blinking of the source image at progress indication and delays at quick scrolling.
  
  
• Local Contrast Enhancement: the "Object part" option functions as post-filtering, i.e. cancels changes if the number of changed pixels in the mask is less than the specified value.
  
  
• The Autodetect Laces utility is optimized (from 3 minutes to 5 seconds).
  
  
• The bug is corrected: any action on the object (undo / redo, joining, closing) didn’t cancel the previously started Move mode of the Editor and thus caused unpredictable results.
  
  
• The bug is corrected: the try to make an unloaded image current after selection of an image tool could cause an abnormal termination of the work.