Raster is a data format consisting of regular grids of values, usually stored in an image-like format.

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Are there any examples of WCS getcoverage requests done using ajax?

I am looking through openlayers to try to figure out a consistent format for generating views of coverages that can satisfy any wcs server, but mainly I'd like to get geoserver coverages. While I've ...
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1answer
215 views

Using rasters/features created at 10.0 in ArcGIS Desktop 9.3?

I am tempted to go back to ArcGIS 9.3 from ArcGIS 10. For what I do, 9.3 is more efficent. I know I cannot open ArcGIS 10 documents (maps, scenes) and layers in 9.3 unless saved as 9.3 file, but ...
13
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2answers
6k views

Differences between Raster Dataset, Raster Catalog, and Raster Mosaic

I have about 40 scanned, colorful Geology maps that are GeoTiffs. I want to bring them into an Esri FileGeodatabase to lower their size, combine them as one and display them with a mostly transparent ...
4
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1answer
891 views

How to sum or even perform more complex mathematical operations (multiply, add a constant, …) two GDAL grids?

I have two grids with same cell size, same starting position (top left) and same grid size. I want to sum the grids and create a sum grid as an result: e.g. grid A + grid B = grid C How can I ...
2
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1answer
945 views

How to replace values in rasters in directory 1 based on condition on other rasters in another directory?

Having 10 raster files in one directory and another 10 rasters in another directory and both have the same dimensions. directory 1: files1 <- list.files("C:\\2010", "*.envi", full.names = ...
5
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3answers
886 views

Finding outliers with wrong Z values in LIDAR data

I have more than 2000 XYZ (only ground points) .txt files and I have to do Quality Control (QC). Let's say I have file, which I converted to multipoint (or even singlepart feature). I have mean Z ...
5
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1answer
341 views

How do I write XML metadata with Python?

Some Python software I have written generates raster files via GDAL. I would like the software to create an XML metadata file for each raster so that I can include details about how the raster was ...
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0answers
97 views

Four band raster - ColorInterp of the IR band

I have a four band aerial photography raster. The bands contain Red, Green, Blue, and IR data. Using GDALInfo we get something like this currently: Band 1 Block=2933x1 Type=UInt16, ...
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2answers
699 views

Calculate Percent coverage using another raster, with dif resolution and orientation

I have a 0.5 meter raster that defines presence or absence (cells are either 1 or 0). I have another 5 meter raster, which I created. I would like to calculate a percent coverage of the underlying 0.5 ...
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1answer
180 views

Scanned Transparent Map Overlay

We have a flat file of 50 Geology maps that have a transparent overlay with faults and drill holes. I have them scanned and georeferenced as TIF images and they will be used in ArcGIS 10.0, 10.1 and ...
3
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0answers
143 views

Is there a tool for automated quality assurance for vector data captured on raster data?

I wonder whether is any tool(or script) in ArcGIS or QGIS which allows to make an automated quality assurance for vector data captured on raster data? vector data on binary raster:
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1answer
208 views

How to get the absolute raster row / column of rastercell when using ArcObject Raster Cursor?

When using the ArcObject RasterCursor (see snippet below), how do I get the absolute row / column of the current pixel value? IRasterCursor rasterCursor = raster.CreateCursorEx(null); do { ...
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1answer
842 views

How to assign new values to a raster attribute table - by comparing two fields?

I have created a new raster from two raster datasets using combine operation in ArcGIS. The new attribute table has two fields from the input rasters. What I need is, to compare these two fields and ...
3
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2answers
799 views

Majority filter (minimum mapping unit) in ArcGIS Desktop with larger window size?

I want to run the majority filter in ArcGIS Desktop with a window size of 4 or 5 i.e. greater than the default 3. Is it possible, or is there some other command (or tool) which might help me achieve ...
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0answers
48 views

How to Convert Multiple Raster in to NettCDF in Arcmap 10.1?

My name is Paresh Chaudhary and I've worked in the field of Geometics since 2008. I have 30 day by day surface temperature images of MODIS, aqua satellite. Now i want to convert it into a NetCDF ...
3
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1answer
361 views

Can ArcGIS handle missing values to create a contour map?

I am trying to create a contour map for a waterbody. It turns out that in several locations there is no data. I just don't want to use the missing values as zero in ArcGIS because it would create ...
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0answers
133 views

How can I create a multi layer exportable file (.xcf .psd) from multiple raster image in QGIS?

I have many raster file of the same zone but in differents spectral bands. I would like to create an exportable file of a small portion that can handle different layers. So in practice I would like to ...
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0answers
132 views

Are there limitations with gdal virtual raster option?

I am new at Postgis and I'm groping... I pretend to rasterize some weighty vector layers in Postgis, do some map algebra and reclassification with them and visualize intermediate as well as final ...
2
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1answer
114 views

Displaying raster attributes on data driven pages

I have a feature class of 50 properties that are ranked. I have a photo for each property stored in a raster attribute column (in the feature class) called "Picture". I am trying to create a Dynamic ...
5
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1answer
2k views

Save Visible WMS layer to file

Is there tool to save currently visible WMS layer to file in QGIS, or some place in QGIS where you can get needed xml to fetch it using gdal ?
2
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1answer
198 views

How to reclassify grey scale tiff in qgis

I downloaded a raster image of the sea floor age. The values in band 1 ranges from -32768 to 32767. I need to reclassify it to no. of million of years to make sense of the data. How can I do so? I try ...
3
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1answer
797 views

Model builder - Nesting models to extract raster values to points

Hello! Hopefully a quick question. I have a simple model below that iterates through a folder full of rasters, taking each in turn to extract data values based on a single shapefile of Random point ...
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2answers
2k views

how to convert grid from Saga gis to have raster in Arcgis?

i am new in Saga Gis, i created grid- LS factor (from Rusle equation for erosis) in Saga gis and now i need to "put" it to Arcgis. How can i do this? I tried a lot of possibilities and none of them ...
5
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1answer
96 views

Best Practice for maintaining a “Cleanup Floor”

I do not have a GIS background and was hoping that someone could point me in the right direction as to the best procedure / software to do the following. Starting with a current LiDAR survey, I need ...
7
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1answer
2k views

How to calculate the flood volume using a LiDAR DEM and a HEC-RAS floodplain polygon

I’ve got a vexing GIS analysis problem which is conceptually fairly straightforward, but in reality more challenging to figure out…. Basically, I need to calculate the VOLUME of floodwater within a ...
2
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2answers
218 views

How do I stop null values from being assigned extreme color values?

I have a raster surface that I kriged in Surfer and imported to Grass GIS but when I view it in QGIS, the null values outside of the interpolated surface take an extreme value and wash out the ...
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3answers
2k views

How to represent trend over time?

I have a time series of rasters where the cells of each raster represents some value at a certain time. I'd like to generate a map that highlights the magnitude of positive or negative trends in this ...
2
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1answer
140 views

What is No Data Value?

I'm looking at the transparency window of the layer properties of my "Heat map". How does the No Data Value effect a raster layer. I'm assuming an initial setting of -9999 sets it out of the way, so ...
7
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1answer
4k views

Best Way to Handle Many Raster Files in QGIS?

I have a project with a large number of raster files, but it is becoming very slow. I wonder which is the best way to handle all this. I'm simply georeferencing these files creating .wld file (geoTiff ...
3
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2answers
1k views

How to calculate the area of rasters in QGIS?

I have been working with some rasters and would like to know how to calculate the area occupied by one element of a raster in Qgis.
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1answer
604 views

What are Bands, Dimensions, and Histograms in QGIS?

First; I can see a band as synonymous with a channel in an image editing program like GIMP, is this correct? If so then bands play the role of color mixing and masking. Are there any other ...
3
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1answer
88 views

What defines a Class in the Heat map plugin?

What defines a Class in the Heat map plugin? As in: "Black holes like that are usually caused by raster values exceeding the range of the color ramp. Try adding another class with a higher associated ...
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1answer
808 views

Calculating distance from points to different class in raster

I am looking for some advice on how to calculate the distance from a point to a different class of a raster. Specifically, I have observations (points) of animal use overlaid on land cover data. For ...
3
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1answer
2k views

How to convert jpg file to shapefile? [duplicate]

I am developing a GIS application like this: By now my steps are: I have got a jpg file, 5040 x 8179 dimension. In this map, the roads, rivers, towns etc. are marked. I am using .Net to develop ...
3
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0answers
158 views

How does Zonal statistics handle pixels that are on the border of the polygon?

I am using the plugin zonal statistics to calculate the sum of the raster cells within polygons. How does this plugin handle pixels that are on the border of the polygon, are those cell values ...
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1answer
126 views

Problem loading raster to PostGIS using QGIS

I am having trouble loading a raster (.asc) file to PostGIS 2.0.1 using the plugin Database - PostGIS Raster - Load raster to postgis in QGIS 1.8.0 on Win Vista 64 bit. I get the following error ...
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1answer
257 views

Qgis - Raster clip Problem

I tried to use the Raster (Extration) tool "clipper" and I always get this error log: What is my problem? Fehler bei der Ausführung von Python-Code: Traceback (most recent call last): File ...
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2answers
3k views

How to count and rasterize polygon overlaps in ArcGIS Desktop?

How do you take a vector layer with overlapping polygons and turn it into a raster where each cell counts the number of polygons containing that cell? We are looking at polygons of fire burn areas ...
2
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1answer
178 views

filter / generalize elevation points on the basis of some conditions

I wanted to generalize many elevation points in a rectangular area (about 700 square km). I need to take about 3 points for square km. These points must satisfy some conditions: One of these ...
2
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2answers
411 views

Getting 2147483647 and -2147483647 as min and max output for point to raster, polygon to raster, and feature to raster tools

No matter which feature to raster tool I use (feature to raster, point to raster, or polygon to raster), I am getting a raster output whose min and max values are 2147483647 and -2147483647, ...
2
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4answers
500 views

Stuck in loading raster to PostGIS

I am running running Mac OS X (10.7.5), PostgreSQL (9.2) and PostGIS (2.0.2) (installed via Postgres.app). The PostGIS extension seems to work perfectly with vector and raster layers. Once I enable ...
2
votes
4answers
691 views

Raster dataset doesn't exist error

Dataset exist and I am able to get statistics from ArcGIS python window. But it failed as a script with error: ERROR 000865: Input raster: C:\temp\ras does not exist. I have tried following ...
3
votes
1answer
194 views

Reclassification of environmental values

I've started to use Qgis recently. I have a logical question. I'm trying to reclassify a raster. The values in the raster are depths, obtained by an interpolation. The original depth values (of the ...
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0answers
31 views

Polygonize Raster to Vector Error [duplicate]

I have a problem when I am trying to Polygonize (Raster To Vector). I have a Corine map with 44 different land uses. I run a query and I save the selected areas with Bands 0 and 1. Now I am trying to ...
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1answer
47 views

Isolate And Save Raster Features From Existing Multivalue Raster Map

I have Cyprus Corine map with 44 different types of land use. I want to run a raster calculator query or any other way to isolate the areas with codes 10 to 22 and 26 to 34, all other values 1 to 44 ...
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2answers
575 views

How do you use 'reclass' in GRASS?

It could be user error, but for some reason, the reclass tool is just hanging and hanging... QGIS 1.8 Compiled against GDAL/OGR 1.9.2 Ubuntu 12.04.1 Running the tool from the Sextante toolbox Input ...
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1answer
109 views

Sextante (SAGA) “Normalisation” problem

I don't understand the SAGA-module "NORMALISATION". In SAGA Gis I just can define one MIN and one MAX value. In QGis I have to define 2 of both. How to handle that exactly?
3
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4answers
192 views

Combining UK OS Historic Digimap Tiles

I'm assisting a retired user in combining a large number of raster tiles downloaded from Historic Digimap http://edina.ac.uk/digimap/description/historic_overview.shtml into one project in qgis. I'd ...
2
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1answer
349 views

How to flip X and Y coordinates of a grid by GDAL

I have a grid, which has flipped X and Y coordinates (X is represented by Y values and Y is represented by X values). This results in grid being positioned in completely wrong place. How can I flip ...
4
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2answers
266 views

How to create a colormap where colors diverge at value 0 in QGIS?

I calculated a raster as difference of two other rasters. Now I want to create a colormap where one colour represents negative values and one colour positive ones. The two colours should become ...