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

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How to set min and max value for stretchType: esriRasterStretch_PercentMinimumMaximum

How can I set the min and max values for the stretch type "Percent Clip" in arcobjects? It's possible to set the Stretch type: rasterStretch.StretchType = ...
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57 views

Save map in raster format from QGIS using compression

Is there a method to save a map in raster format from QGIS using compression? For exemple from "Export map" in ArcGIS there are many options to compress the images depending on the file type (tiff, ...
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15 views

Has anyone success using subset an image such as NAIP?

Has anyone any luck subsetting a small part out from NAIP? I'd like to hear your feedback on pros or cons on how to subset an image from NAIP despite they are in mrsid and their uncompressed file size ...
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29 views

Raster: how to locate cells having nodata

I am new to oracle spatial. I am using SDO_GEOR package's getNoData prcedure. the results are populated in following format. MDSYS.SDO_RANGE(MDSYS.SDO_RANGE(-32768,null)) My questions are: Is ...
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9 views

QGIS Raster moving when Majority filter

I'm running QGIS 2.01 Dufour on Linux Mint. Data & project are WGS84. I'm trying to smooth a grid & following other posts here I've used the Majority filter. This is looking helpful, but the ...
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32 views

In qgis using python, how can I get multiple pixels from a raster based on a vector point file

I just started working with qgis, and for the life of me I cannot figure out how to solve this problem: I have several points of interest, these are stored in a shape file (just simple points). I ...
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2answers
24 views

Remove sections, defined by a line or polygon, from a raster in QGIS

(QGIS 2.6.0 on Windows.) I have created a raster layer of heights using the TIN interpolate function. I also have another raster layer with more accurate information on the height of particular areas ...
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26 views

fit point with raster data figure out those points belong to, and add column and row to represent it in ArcGIS 10.2.2

I have an X-Y point data file, with which has latitude and longitude. I'd like to be fit it with the raster data, then add column and row data on the X-Y point data file. first i created the attribute ...
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2answers
54 views

How to calculate percentage of selected area from DEM?

I am working with elevation data and performed a local operation to convert it from meters to feet. I am interested in finding the area (expressed in percentage) that is above 4000 ft, but I have ...
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2answers
20 views

Creating new raster based on spatial extent and classes of one raster and average of another using ArcMap?

I have a raster that is split into classes and I wanted to make a new raster with this raster's spatial extent and classes but displaying the average values from a different raster. I am not really ...
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1answer
24 views

Percentage of a polygon at, or less than, a specific height (supplied by a raster)

I am using QGIS to process some LIDAR data. I need to be able to define the area of a pond with respect to its depth (i.e it is 100m^2 at 32mAOD and 500m^2 at 33mAOD). Is there a way of finding the ...
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47 views

Using raster to clip vector data

I have high res raster data covering 2million km sq, with a field where each cell has a value from 0 to 100. I need to create a "mask" using the cells with a value over 12 in that field. I then need ...
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1answer
112 views

How to rename multiple rasters with modelbuilder

I have 101 raster images stacked inside a folder. The Rasters are of arcinfo grid type (*.asc) while having a long string name 'NW2D_T100_05_base_depthXXX.asc' where XXX ranges from 000 to 100. What ...
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7answers
14k views

Get boundary of raster image as polygon in ArcGIS Desktop?

I have a rectangular raster image in ArcGIS. My question is: how can I produce a polygon which is just the extent of the raster image? That is, I want to have a polygon layer with a single ...
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2answers
344 views

Can I prevent QGIS raster clipper from changing output cell/pixel size?

I have performed a DEM extraction using the clipper tool in QGIS 1.9.0 Master, using a mask layer, the original resolution of the DEM is 20x20 but in the resultant DEM the new resolution is ...
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80 views

How to decide how to “stretch” raster imagery?

I have to symbolize a digital elevation model. ArcMap offers many different setting for stretching the symbology which all give widely different results. Some stretch methods symbolize the data so ...
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1answer
63 views

What effect does standard deviation have on the display of DEM rasters?

I need to explain why ArcGIS offers the function "standard deviation" when symbolizing rasters with the Stretch method. The Standard Deviation is a measure of how spread out numbers are and is ...
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1answer
27 views

how to make mapnik style raster, not just render as solid color

I have set up Mapnik with mod_tile and renderd. I replaced the default osm.xml file with my own xml file, which is shown below. My problem is that all images are being created as solid blue tiles as ...
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2answers
60 views

How to clip vector data from raster data?

I have two files: National land cover data (raster) HUC 8 (vector files of watersheds) Both are national scale but the HUC 8 takes up a larger geographic region than the raster set so I want ...
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4answers
87 views

Apply Symbology to Rasters using Arcpy Script

I have an ArcPy script to apply the symbology of one raster layer to all of the raster layers in the table of contents. I have used this script before with feature layers instead of raster layers, and ...
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1answer
54 views

Modifying raster values in a zone with a math expression

I'm currently doing an SIG project with the goal of calculating groundwater volumes in chalk and silex residuals aquifers. I have point data of underground water, chalk roof, and floor elevations, as ...
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32 views

raster and vector misalignment

my vector and raster datasets align perfectly fine in Arcmap but not in QGIS, any suggestion on solving this dilemma is very much appreciated.
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250 views

Floating point calculations in QGIS

How do I manage floating point calculations in QGIS? I have carried out 3 consecutive calculations on landsat bands. I end up with 32 bit floating point rasters on which I can't carry out a 4th ...
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4answers
43 views

How can I join all data of two raster datasets in ArcMap 10.2?

I have two raster datasets in ArcMap10.2. One is displaying rails and one that is displaying a 100m Buffer to both sides of it. My cellsize is 100x100m. What I want is to combine the rails AND the ...
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65 views

QGIS raster symbology problem in 2.6

With the new 2.6 QGIS version I often have problems with raster colors. For some reason certain pixels do not display initially, but if I move the raster a little spatially they show up.
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159 views

Save As in QGIS 2.4

I am trying to save edits to a raster file in QGIS, but; When you edit a raster file and select "Save As"; no output file is generated. My version is in Spanish; however "Save as raster layer" is ...
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606 views

ArcMap 10.1 - Tabulate Area tool “doubling up” for Overlapping Buffer Zones

This question is related to a previous question I asked: Raster Version of Spatial Join (one to many) I used the Tabulate Area tool to crosstabulate values between an overlapping "buffrast" raster ...
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1answer
89 views

Getting Uncompressed Size of Raster using ArcObjects?

How can we get the Uncompressed Size of a raster as shown in the layer properties below using ArcObjects?
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171 views

Rasters added to mosaic dataset only display at large acale

I have a set of 357 rasters in .jp2 that I've added to a mosaic dataset. All but 7 of them display properly, but the 7 only display at larger scales, around 1:6500 and under. I've tried adding them ...
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1answer
231 views

shortest distance between a raster and another raster

i am using arcgis 10.1 i want to calculate the shortest distance between a raster and another raster. i have a bathymetric raster and an underlying fault plane raster. for each bathy raster cell, i ...
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3answers
39 views

How to narrow raster features to single cell width?

Are there any tools or existing workflow which convert raster features (such as roads, rivers, electric lines etc.) which are (or can be) multiple cells wide to a single cell widht (i.e, center line). ...
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problem in raster data with arcmap 10

I have a problem when trying to load raster data (a TIF) in ArcMap. ArcMap 10 instantly shuts down and the well known window appears "ArcGis Desktop has encountered a serious application error and is ...
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19 views

Web Server/Technology to work with Raster-Imagery Data

I am in the process of designing a web application which will allow the end users to load raster imagery data (size range from 300 MB to 500 MB) as a back ground map and a corresponding OLD JPEG image ...
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37 views

Creating a Raster of Road Distance to Point

I am using QGIS 2.6. This question is in two related parts: I'm trying to create a raster of travel time from one point to another point travelling via the road system. Each raster pixel will roughly ...
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210 views

How to change field name in raster file?

I´m having a bit of an understanding problem with a DEM TIF file. I have a DEM TIF file which is served with Geoserver. When I click on the layer the WMSGetFeatureInfo gives me the following output: ...
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36 views

Arcpy reclassify all values to same number

Using ArcGIS 10.1 and arcpy, is there a way to reclassify all values of a raster file to the same value (leaving NoData Values as "NoData")? Lets assume that I have no way of knowing what the actual ...
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1answer
99 views

Classified Images of RandomForest-Classification look clustered

I performed a RF-classification. I have 6 bands, ~250 trainingpoints in a shapefile, OOB estimate of error rate: 1.56% Picture of take trainingpoints added. My code: ...
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5answers
2k views

Is Hillshade option in ArcMap rubbish or is it me?

Here is a pretty pic of the raster I am using - with no effects applied - just the color ramp and historgram adjusted to show out all the relief - all be it in a very 2D way! I have a raster layer ...
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1answer
32 views

Defining polygons based on thickness maps using ArcGIS for Desktop?

I want to find and create polygons that demarcates three different inflection points in a thickness raster: where the thickness start to increase, where the thickness is at its max and where it starts ...
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1answer
412 views

Taudem Resources

As I frequently deal with hydrology, I've heard Taudem mentioned quite a few times. I'm finding all sorts of information, but much of it is dated for use with previous versions. In addition, the ...
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1answer
63 views

Extracting raster values with polylines in QGIS

I have a polyline shapefile that represent a road an a raster grid with slope values. Is it possible to interpolate the shape file and the grid to have the average slope of the road? I know that I can ...
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3answers
3k views

Polygon to Raster Tool Problem

I am trying to create a raster data set from county level polygon data for the US. I have successfully created one raster from a dataset, but when attempting another, it does not work. I am ...
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29 views

area elevation distribution with QGIS

I have a raster DEM and a polygon covering a part of it. I need an area-elevation distribution (i.e. how many m2 are in which elevation interval). 20m intervals will be fine. I cant figure it out.
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1answer
325 views

How to extracting raster data to multiple polygons?

I have a reclassified raster dataset (10 classes) and I want to find out the area of each class contained within multiple (hundreds-to-thousands) polygons. I have all the polygons in the same ...
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22 views

Raster overview hierarchy in WMS [duplicate]

I have rasters with low resolution which covers the whole area, and in certain spots i have some rasters with higher resolution which covers small parts of the same are covered by the lower raster ...
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3answers
70 views

Creating buffer around particular raster cells using ArcGIS for Desktop?

I would like to draw 100m buffers around particular raster cells (artificial surfaces) in my LandCover raster layer in ArcMap10.2. The Buffer tool only works with polygon and the Expand tool always ...
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22 views

Adding Raster Layer in C++ application always result in layer invalid

I am trying to add a raster layer in c++ application with QtCreator and QGIS 2.6.0. My code is as follows: QgsRasterLayer * layer = new ...
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1answer
58 views

Do rasters other than “north up” exist in the wild?

"North-up" (as I understand it) refers to raster images stored with the northerly direction at top, and each subsequent line of pixels is a bit farther southward. Rasters' georeferencing metadata ...
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29 views

Prepare raster data for wms using geoserver!

I have some orthophoto of different resolution (urban 8cm pixel, hill 20cm pixel, mountain 35 cm pixel) which cover an area of 28000 km2. Those are in jpg format, already georeferenced. I need to ...
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259 views

Is there a standard for the coordinates of pixels in georeferenced rasters ?

We are working with different raster datasets, and the pixel coordinates are either stored at the center of the pixel or at one corner. The information is usually provided in the metadata, but ...