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

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count band numbers from multiband raster image

My raster image has 10 bands (10 bands are 10 year), cell values of each one are 1, 2, 3. One is negative anomaly, 2 is no change area, 3 is positive anomaly. Now I want to find how many years out of ...
9
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5answers
3k views

How to modify single Pixel values in QGIS?

I would like to modify a raster (pixel values) in QGIS. The plugins "value tools" can easily provide me with the value of the pixel of my raster. However I don't know how to modify it. I have found ...
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8 views

Segmentation and Classification in ERDAS

I have segmented an image inn erdas and will want to use it in a classification exercise, how do i proceed? My image is a low resolution 30m alos.
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0answers
18 views

C++ code and ArcGIS Button

I have some code in c++ that used gdal and process raster and create an output raster. I want to create a button in ArcGIS Desktop (using ArcObjects SDK 10.2 c#) and pass the raster layer to my c++ ...
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2answers
55 views

PostGIS polygon clip inaccurate using ST_Clip and ST_Union from tiled raster

I have a RGB raster tiled at 128x128 in PostGIS enabled database. I am trying to clip from the raster using a polygon as follows: SELECT ST_AsGDALRaster(rast,'GTiff') FROM ( ...
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0answers
6 views

Help with Raster files and Colour ramps [on hold]

(A)I wonder if there is any general help with Raster files for QGIS? I am encountering some problems related to GRID files that have attribute tables attached in Arc but the attributes don't show in ...
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1answer
156 views

Combine overlapping rasters in gdal_calc.py, taking the maximum value from each pixel?

I want to combine 3 overlapping rasters to create 1 raster. Each have the same dimensions, resolution and CRS. I want to populate the new raster with the maximum value from each of the layers. ...
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4answers
310 views

How to convert a vector map to raster in Qgis?

I am creating a thematic map (vector data) with different classes. How to convert this vector map to a raster map, keeping the classification?
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1answer
115 views

How to use USGS Bulk Download on EC2 linux Server?

I am interesting in downloading Landsat 8 rasters to an Amazon EC2 instance and would like to know how to do it. I already install USGS Bulk Download but I do not know how to use it in terminal mode ...
2
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1answer
19 views

replace raster cell values with values in a .csv

I'm looking for a simple way to replace the value field in GRID format with values that I have in a csv. It would be much like doing a join, where the GRID and the csv have a FEATUREID and then ...
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3answers
1k views

How to extract X Y coordinates and RGB from pixels using python in QGIS?

I'm trying to white a Python plugin in QGIS (2.2) to get, for each pixel of a raster image, its X Y coordinates, as well as, its RGB (3 bands) values. At first I opened the raster file using: rlayer ...
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0answers
17 views

How to combine two different raster by replace its raster value at their overlap space? [duplicate]

I have two different raster data : First data : Second data How to combine those raster data? so the output data will be like this : Where the overlap space between First data and second data ...
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1answer
88 views

Zonal Statistics Freezing QGIS 2.2

Running on Windows; 8gb memory, 500gb HD, i5 cpu; Raster file: 250mb I am having a problem with zonal statistics advancing past 17%. I am trying to run statistics on a crop grown in certain counties. ...
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3answers
364 views

Geodjango read raster files

I am developing a web app in geodjango (django) framework but I need to import raster files. Is it possible a geodjango app read raster files from a directory? Thanks
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0answers
14 views

multiple attributes in csv file to raster

I have a several large comma separated text files each with multiple attributes. Each text file is about ~2.9 GB with 21 million lines. Each line contains X, Y, VALUE1, VALUE2, VALUE3, etc. The X and ...
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0answers
20 views

Is QGIS aspect analysis description mistaken?

I've been checking the Aspect analysis tool and several sources indicate that aspect is measured from 0 to 360, starting North and going counter-clockwise. Nevertheless, I've been testing it on ...
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0answers
12 views

Custom data source for GeoServer raster image

I'm working on a project where a custom binary data file contains latitude, longitude, and temperature data. I'm interested in creating a DataStoreFactory plugin to enable GeoServer to load this ...
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38 views

Aggregate / Calculate Cell Statistics >1000 Rasters

I'm looking for a tool/script that does simply what "Cell Statistics - Mean/Sum" in ArcGIS does but for more than 1000 Rasters (TIF) (I need to process ~10000 Raster at once). I'm not used to use ...
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1answer
151 views

How to fill holes/missing values in XYZ data / a DEM with QGIS?

I have equidistant XYZ point (text) data that I used to create a point grid. However, it's not perfect - there are some holes. I then created a DSM raster from it, which obviously has the holes too. ...
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2answers
62 views

How to sum pixel values of a floating point raster in ArcMap?

I have a floating point raster with values from 60 up to 95 (with decimals), it has 7077 pixels of 250x250m size. Is there a way to sum all pixel values of this raster? For example, if the raster had ...
2
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1answer
2k views

Creating raster map using Excel file and calculating averages?

I have thought about using ArcGIS to create a raster map of latitude/longitude (0 to 360 degrees) temperature data (in Excel format). This temperature data reflects the total amount of warming that ...
2
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2answers
241 views

Python Script tools for ArcGIS 10.2 is very slow (get raster properties)

I am using python script tools for ArcGIS 10.2, under Windows 8.1 64bit. When I am using the arcpy.GetRasterProperties_management() command, it's very slow to process the data. For example. I tried ...
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22 views

IRasterLayer background transparency in C++ with ArcObjects 10.x .NET

I have a georeferenced IRasterLayer which is displaying data with no alpha channel. I am trying to specify a color which should be treated as transparent. In ArcMap it is possible to set a specific ...
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2answers
44 views

Changing raster calculation values - shorten this script?

i'm doing something quite straightforward regarding raster algebra but am struggling either to find the correct function or make a function work correctly; Basically I have 2 rasters, representing ...
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1answer
532 views

mosaic raster to file geodatabase yields missing raster sections

Since upgrading to ArcGIS 10.1 (SP 1) from 10.0, I've been encountering an issue when running the arcpy.MosaicToNewRaster_management() tool with output to a file geodatabase. I'm principally working ...
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3answers
320 views

How to subtract rasters using the gdal_calculate command

I just want to know how to subtract two raster using gdal_calculate command? Or what is the proper way of subtracting using this? Any idea would be greatly appreciated. Note: gdal_calc is different ...
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3answers
645 views

What causes RuntimeError: ERROR 010240 saving after CellStatistics?

I am having trouble saving outputs from CellStatistics but only when I run it on a list of rasters. This was working on python 26 but not 27. I know this example is nonsense, but: env.workspace = ...
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0answers
40 views

Converting large rasters to NumPy

I have a geodatabase that contains a large number of raster datasets - there are two rasters for each country in the world, and they are very large, in some cases up to 3GB per raster dataset. I ...
2
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1answer
26 views

Rasterization of point vector in QGis: how to align the resulting raster to an existing one?

I have a point shapefile, with no associated .prj file, that I have to rasterize. Each point should be transformed into a pixel of 30x30 size aligned to the pixels of a Landsat image (the point file ...
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0answers
15 views

Reclassifiy raster in R [duplicate]

I have a raster file which has been classified from 1 to 255. I have to reclassify into binary form where 1 to 11 must be classified as 1 and the rest must be 0.How would I be able to do it in R. My ...
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9answers
11k views

How do I create a shapefile showing footprints of Rasters?

I have around 1,000 satellite images in tiff format, and I want to create a shapefile which will serve as an index to the rasters. This is something similar to a raster catalog, but I do not want to ...
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20 views

export several rasters from grass

I'd like to export 127 raster files from grass to .tif in one operation. I already stumbled over this post How to batch export using r.out.gdal command in GRASS but it doesn't work (I don't even know ...
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1answer
527 views

Building attribute table from raster in ArcMap?

I'm using ArcMap 10.1. I have a NetCDF file containing the latitude, longitude and porosity for the entire US. I am trying to add another value (wilting point) which depends on the porosity. I ...
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1answer
21 views

QGIS GRASS raster to GeoTiff

First of all: Windows 8.1 QGIS 2.8.2 Wien My problem is that I used the GRASS module r.watershed to delineate watersheds and get flows with a DEM. It worked fine so everything is OK so far. But ...
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0answers
14 views

Is QGIS Server working like this?

On CentOS 7 I have QGIS Server and QGIS Desktop installed. In QGIS Desktop I created a project with raster and vector data and saved it in a ".qgs" file. Then I copied the file in ...
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2answers
70 views

What percentage of polygon x is in raster pixel y, efficiently

I feel this is a competition worthy problem, due to its size. I would like to weight a set of raster pixels to the attributes of a set of polygons. To do this I need to know the proportion of each ...
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0answers
19 views

Subset moving window when using focal on raster in R

I have a classified Landsat image, and I'd like to pass a filter over it converting certain cells to 0. For some categories, I'd like to set cells to 0 unless an entire 7x7 window contains only that ...
2
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0answers
29 views

Using Terrain Profile plugin with an interpolated raster

I am very new to QGIS and the goal of this exercise is to view an elevation profile of a river from a set of discrete points taken from surveying records. Steps taken: A vector layer was created ...
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2answers
57 views

Computing View Distance in One Direction from Point on Elevation Raster in PostGIS?

I'm a software developer just getting into GIS, so please forgive me if I don't use proper lingo, or if I use proper lingo incorrectly! I have a raster of elevation data. For a given point in the ...
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1answer
136 views

Extracting the pixelwise proportion of classes of a finer raster in a coarser one

I have two rasters, one has a 1 km resolution. The other has a spatial resolution of 30 m. This latter pixelwise is a classification. I want to overlay the 1 km raster on the classification raster and ...
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1answer
208 views

Tools for building and exporting high resolution geotiff

I'm having some really nice raster maps in geotiff format. I would like to add some features to these maps as well as then exporting them as tiles for serving the map from a web server. Preferably I ...
2
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3answers
489 views

Raster map in different zone () than region ()

I am new to QGIS (just installed QGIS 2.0.1) and am having problems running any spatial analysis tools. I followed the instructions on how to call GRASS tools into QGIS, but when I try to run the ...
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0answers
17 views

Achieving consistent RGB Composite Settings using ArcPy?

Does anyone know if there is an arcpy tool so that when I bring in raster imagery (Specifically Landsat) into ArcMap it will automatically adjust the settings of the RGB composite? I know under ...
2
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1answer
148 views

Same Raster but different min/max in ArcMAP and QGIS

since I am abandoning windows to stay only with Linux, I started learning how to use QGIS. So far so good. However, trying to reproduce a python script from Arcpy to PyQGIS I noticed something. When I ...
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1answer
782 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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2answers
26 views

Combining several mask rasters to obtain one single mask with binary values

I have a series of separate rasters which represent the cloud cover over the same area but in different months. Each raster has 2 values: nan for "no cloud" and 255 for "cloud". What i want to do is ...
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3answers
201 views

Benefits of *.las vs *.xyz or *.ascii when working with LiDAR in ArcGIS for Desktop?

From time to time, we use lidar data for modelling in arcgis. Previously, we would be supplied either an .xyz or .ascii of the data, but more recently, we are also being provided .las files in ...
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1answer
148 views

How to know the GSD (grid size, resolution) in meters of an existing raster when working in Geographic coordinates?

I would need to know the GSD or grid size (resolution), in meters, of a raster created when working in a Geographic coordinate system in ArcGIS. Is is possible? Even better, can I set the Cell size ...
2
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1answer
300 views

Can I update the service on ArcGis Server programmatically?

There is Windows Service. This service adds user raster data to the Raster Dataset in sde database. The Raster Dataset registred on the ArcGis Server. This Raster Dataset also was publishing on ...
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2answers
233 views

Understanding min and max values with Mosaic to New Raster?

I have to combine several DEM rasters into one from this source: http://srtm.csi.cgiar.org/SELECTION/inputCoord.asp, so I use Mosaic to New Raster tool. I set up the tool: I input the rasters (all ...