The process of converting features on a map or image (either hardcopy or digital) to vector-based data in digital format.

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2
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1answer
247 views

How to find the projection of an image?

Instead of georeferencing the image and deforming it, I'm trying to find the projection used by the author of the image. I've got tens of these distribution maps to digitize. The idea is to avoid ...
2
votes
1answer
274 views

Heads up digitizing - Polygons overlay differently with two different Satellite images

I have been digitizing building footprints from satellite image using ArcGIS 10.1 . Field data collections is done with the use of four corner point GPS way point. Due to multipath errors, we are ...
2
votes
1answer
313 views

using the “freehand” construction tool

I am drawing hydro features with the freehand tool. Does anyone know how to delete vertices (i.e. back up) in ArcMap 10 while drawing with freehand in the construction tools? I was just curious if ...
2
votes
2answers
147 views

Digitized Shapefile manually using wrong projection: how to fix it?

I have a raster in correct projection. I used shapefiles, and marked objects (manually), but I found out that my vector layers have different projection, so they have different size and position. Is ...
2
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1answer
2k views

When I finish drawing a polygon, it disappears again (although appearing in my attribute table)

I'm working with Quantum GIS at this moment. And as the title says, when I finish drawing a polygon, it disappears again. The new object does appear in my attribute table and in the legend/'filling of ...
2
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1answer
82 views

What program can I use to highlight and calculate multiple areas on a satellite image?

I would like to calculate the area of all the parking spaces in my city (North Miami Beach). I would highlight the parking in two layers, commercial and residential, and then export it to Excel and ...
2
votes
1answer
231 views

How to implement Add feature action from PyQGIS

I'm trying to implement / reuse Add Feature functionality in my python plugin. there a class/function that handles geometry creation on canvas based on layer geometry definition? I'm checking API but ...
2
votes
1answer
580 views

“Node tool: could not snap to a segment on the current layer” message

I have a strange issue. Editing a layer with node tool I get always the following message: "Node tool: could not snap to a segment on the current layer." This error happens to me even with a fresh ...
2
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0answers
39 views

Digitized points are getting displaced automatically in QGIS

We are capturing 100's of drilling sample locations in QGIS. At times, we are copying the whole set of points from adjacent survey_lines to the next one. After that, we will capture the respective ...
2
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0answers
73 views

How to avoid topology errors when digitizing a road network?

I am working on a road layer project. For the snapping option I'm using the mode to vertex and segment and tolerance 5 pixels. When zooming in (to the max) I do not notice a gap. But when I use the ...
2
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0answers
38 views

Geometry issues when digitising in QGIS

I'm digitising a large number of maps from hand drawn mud maps and digital images, and although I have used the snapping tools ("snap to vertex and segment", Tolerance 10 pixels, avoid intersections) ...
2
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0answers
30 views

QGIS 2.8.1 (Windows 64bit). Setting snapping to the “decoration” grid?

I was wondering if anyone knew of a way to snap digitizing to the grid you can create in View>Decorations>Grid? I can't see anything in the manual or the menus so I am thinking there probably isn't ...
2
votes
1answer
350 views

Why are my polygons automatically simplified/generalised when merging them in ArcMap 10.2?

I am creating a small land use map, as an exercise for visual image interpretation. I created a shapefile and started digitising polyogons with the polygon tool. The problem is that some of my ...
2
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0answers
67 views

How to digitize a custom road?

So I've built my network and now I am creating custom bus routes. However, one of my bus routes makes a stop on a private road that I had not realized was included in my network. How should I go about ...
2
votes
0answers
900 views

How can I create/draw “freehand” polygon features in QGIS 2.2?

I installed the Freehand Editing plugin but it doesn't seem to work with the latest version of QGIS; the icon appears on the Ditizing Toolbar but the icon is disabled. Is there any way to use a ...
2
votes
0answers
226 views

Polygons of Land Use Change

I am doing a project where I am digitizing a map of Haiti from the 70s. Through R2V I digitized the lines and then I exported it into ArcGIS 10. I am just interested in the land use change, therefore, ...
1
vote
2answers
495 views

Harvest data from an ArcGIS Server

I would like to include some state agency data in an application I am creating. The agency will not share the data so I have to find another approach. What I am interested in are the points on the ...
1
vote
6answers
234 views

In what real-world examples do users still digitize features from a map?

Is digitizing of map features completely dead? For example, when and why do you still digitize features from a map? It can be heads digitizing up from a scanned paper map (or image, or whatever) or ...
1
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2answers
54 views

Which value should I assign my digitalized features?

I have a scanned an old document that contains geochemical interpolated values (no way to work with the digital file). This is the original image: And this is the digitalization I made from it: ...
1
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1answer
63 views

Digitized Map To Scale

Is it perfectly acceptable to produce a map at a scale of 1:24,000 from a database that was digitized from a 1:100,000 scale source map?
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2answers
152 views

How to make digitization more detailed afterwards with QGIS?

I digitized already two areas, bordering each other on one side. Than I realized, more detail was needed! What do you suggest as a fast way to do so? Adding each time new dots/verteces takes so ...
1
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2answers
655 views

convert a *.jpg scanned from line paper map to vector data in arcgis

I want to digitize automatically old paper map that scanned to jpg . I know that it's possible to digitize it with arc-map but I can not remember how to do it.
1
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2answers
41 views

USGS National Map Ortho - Digitizing

As a part of project scope we have to deliver to the Client digitized data sets – some houses and roads. Can we use USGS Orthoimagery from The National Map layer for feature digitizing? ...
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2answers
96 views

How to close a polyline in QGIS while digitizing?

We need to work on a line layer where some features are closed and some are open. The closed features need to be closed perfectly, so that the first and the last point of the polyline perfectly match. ...
1
vote
1answer
906 views

How to go with…somewhat complex geological maps in QGIS?

Just a follow-up to this question QGIS: Line to polygon conversion. Not sure do i have to continue there itself... We are currently digitizing a geological map...which has 36 features in total. Some ...
1
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3answers
233 views

How can I create a simple basemap in QGIS that will allow me to trace a polygon with an accurate projection?

I need to find an aerial photograph, create a new vector layer, trace several fields in this aerial photograph, and find random coordinates within these polygons. I first tried this with the Google ...
1
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3answers
1k views

Auto populating XY fields when new point feature digitized using ArcGIS Desktop?

Is there a way for ArcGIS Desktop to populate a field automatically when a new point is dropped on the map? We have our map in State Plane Feet, and we want to the database to automatically add WGS ...
1
vote
1answer
68 views

Connecting vertices to form a line without using an attribute

I have a number of multipoint features that form lines (hiking trails). I would like to connect the dots of each multipoint feature to generate line features, but there are no attributes with which to ...
1
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2answers
77 views

Edit Geometry with digitizing tools in QGIS of a postgis layer

I have a multiline PostGIS layer added to my QGIS 2.10.1 Pisa. I'm able to add features using the digitizing tools, but I'm not able to use the delete or node tool. It remains gray even if I'm in ...
1
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1answer
123 views

Advanced Digitizing Tools Crashing in QGIS 2.8.1 x64 on Ubuntu 14.04

I'm hoping someone here can tell me what I'm doing wrong... Whenever I use the Advanced Digitizing tools in QGIS, I crash after about 5 clicks. I'm even doing it without OTF transformations on. Any ...
1
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1answer
24 views

Digitizing 2-node lines?

I tried digitizing in to a new sqlite line layer with autoincrement id ticked..... I want to create a 2-node line, but there seems to be a minimum limit of 3 nodes. Is this correct or am I doing ...
1
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2answers
82 views

QGIS: digitized object disappear when filling in attributes

When digitizing, for example a point, the attribute window opens for you to fill in the pre-defined columns/information. But no point is shown in the map while you do this in QGIS 2.6. It was shown in ...
1
vote
1answer
1k views

How to indicate flow of a watershed feature?

While tracing and digitizing rivers, streams, rivulets, etc., is it possible to indicate the direction/flow in the shapefile on QGIS? I'd like to avoid using map labels. Ideally, when done tracing, I ...
1
vote
1answer
550 views

Can I resume (continue) digitizing a polygon feature from any vertex?

When I digitize in ArcMap with a Wacom tablet and a pen I often accidentally double click and finish my sketch. More often then not the accidentally finished sketch crosses itself. I would like to ...
1
vote
1answer
180 views

QGIS: Line to polygon conversion

Currently we are working in a geological project..in which all the Contacts, Linear & some other geological features have to be captured. The thing is most of the features have to be Captured as ...
1
vote
1answer
122 views

Digitized vectors don't match while zooming [duplicate]

I'm trying to digitize in QGIS with Google Maps as the background. Digitizing with constant zoom works fine. But if the zoom is changed, the digitized vectors don't match the Google Maps background ...
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0answers
43 views

Newly added points disappearing after saving edits in QGIS.

I am adding features to a shapefile point layer in QGIS 2.12 Lyon. When I add the new point I can see it, but once I click the Save Edits button it disappears. When I click Toggle Editing button to ...
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0answers
24 views

Rotate functions in “Rectangles, Ovals Digitizing” as well as “Advanced Digitizing” distort shape dimensions

I am trying to rotate squares via the rotate tool in the "Rectangles Ovals Digitizing" Plugin in QGIS. The dimensions/proportions of the sides, however, are distorted whenever I do so. Any idea of why ...
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0answers
24 views

Fill of sketch polygon blocks view of what I'm trying to digitize

I am trying to digitize polygons using QGIS 2.10.1-Pisa, but the red fill of the sketch polygon blocks me from seeing the imagery that I need in order to draw said polygon. I have tried going into ...
1
vote
1answer
52 views

Freehand editing without holding down mouse button in QGIS?

I am trying to delineate wetlands using satellite imagery in QGIS 2.10.1-Pisa. I'm using the Freehand Editing plugin. Is there a way to draw polygons without having to hold down the mouse button, ...
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0answers
56 views

Error in Editing Point Shapefile: I can't add a new point feature

I want to add a point to a point shapefile. I place the cursor in an empty field. The strange thing is that the point of the point shapefile that is nearest to the cursor is highlighted. If I click ...
1
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0answers
34 views

Digitising - Separate fill and line opacities (or remove fill)

I have a client who specialises in aerial photograph interpretation and is in the process of moving from AutoCAD to QGIS. They find the auto 'fill' when digitising polygons really disruptive and ...
1
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0answers
151 views

How to OCR topographic maps

I have old topographic maps that i have scanned and converted into pdf in Actobat XI 11. I need this pdf to be text-searchable (not mere image). To do this i tried text recognition in acrobat but it ...
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0answers
29 views

Best way to create sub-polygons based on underlying basemap

I'm looking at ranging patterns where animals go in and out of nature reserves into residential areas. In addition to home range polygons, I've generated polygons made from applying 25m and 50m ...
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0answers
79 views

How to set a defined distance between nodes to digitize in qgis?

Using QGIS (by now I have the 2.4 version) I would like to set some parameter (I don't know if such exists) that would impose a definite or maximal distance between nodes when digitizing a polyline or ...
1
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0answers
46 views

automated method of Geo-referencing air photos?

I am trying to figure out a way to automate a process to geo-reference ~800 air photos, followed by digitalizing several thousand polygons from these air photos. At a minimum, we would like to create ...
1
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0answers
137 views

How can I optimize ArcMap Editor's streaming mode for use with a tablet such as the Wacom Intuos?

I have the Wacom Intuos 4 Large tablet which I use occasionally outside of ArcGIS. I now need to digitize a large volume of polygons from aerial imagery and am finding the tablet's ArcGIS ...
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0answers
73 views

When digitizing, polygons are inverted

I need to use QGIS to digitize my images. My images are scanning electron microscope (SEM) images of rocks. I am interested in analyzing the pore space in the images. Here is the steps I follow: I ...
1
vote
1answer
29 views

Searching 'select by color' for raster or map data

I'm planing to create an online map component with which the user can create/draw polygons based on underlying raster data. Is there some library / tool / procedure existing which enables the ...
1
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0answers
70 views

When digitizing, objects are not saved well

I've some problems with digitizing. If I draw a line or a polygon, the line or polygon is saved in the attribute list, but not visible and its location is not saved either (when I zoom to the object ...