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

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View information raster data in postgresql

I download and use raster2pgsql.exe import tiff image into postgresql. Can i use the query to retrieve the information of the image does not? Information such as: date of capture, capture time.
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FME - Raster Algebra and Multicriteria Analysis

I'm trying to use FME to do some raster algebra for some Multi-Criteria Analysis. At the moment, I have three rasters, all with the same extents and resolution: Slope, Hydro, and Infrastructure Mask. ...
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47 views

GDAL TIF to JPG Creates Dark Image

I'm using the GDAL Raster>Translate to create JPGs from Georeferenced TIFs. The translation is working, but the resulting JPGs are significantly darker than the TIFs they are being created from. ...
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How can I preserve image quality when combining aerials of different resolutions?

I have two different rasters that were flown at different times during the same month. One has a resolution of 4-inches, the other has a resolution of 6-inches. Using ArcGIS tools, how can I combine ...
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27 views

How to Separate Bands Through ModelBuilder [duplicate]

Q1: I have a .tiff file containing 365 bands. Each band represents a daily variable. I want to separate each band and save as a single .tiff file. In the end, I want to have 365 individual .tiff ...
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26 views

The difference when querying raster and vector

Hi everyone I have two queries have the same meaning but different results. Why is there a difference?. Queries are true? query 1: query 2:
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25 views

Is there a Raster2pgsql GUI?

Has anyone ever attempted to create a raster2pgsql gui (like the shp2pgsql gui). As I am sometimes lazy to use command line, this could be a very nice to have.
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1answer
76 views

Leaflet rendering TileMill tiles in the wrong order

I'm stumped, and quite a lot of searching has turned up nothing helpful. I'm on the first step of what will ultimately be a map with three raster layers and three layers of markers (with controls to ...
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3answers
133 views

What is the math behind rasterization?

I'm taking the first steps in QGIS (version 2.2 Valmiera) and I am having some difficulties in knowing what mathematical criterion that QGIS uses when converting polygons (shapefile) to raster. I'm ...
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28 views

Batch raster conversion

I want to do conversion from WCG to UTM for my 172 Raster, I can't use normal batch because I I can't re-arrange again the order of raster in Table of Content because the result are random name in ...
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what is the math behind rasterization? Doubt [duplicate]

In Figure 4 you can see how the overlap is not complete (marked with circles). What I would like to know which algorithm that QGIS uses the rasterization? What is your standard? Is there a percentage ...
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20 views

Overlay Shapefile and Raster layer in R [duplicate]

I have a raster layer with climate data from the north of Mexico, part of Canada and the US mainland. I am trying to restrict the climate data to only the zone of the US mainland. To do this I thought ...
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32 views

How do I mask a raster in TileMill?

I've tried just about every single TileMill compositing operation on the vector and raster layers in question, and I have to admit that I can't figure it out: How the heck can I mask a raster with a ...
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2answers
37 views

Build a Raster GIS Web Application

We need to build a Web based GIS application for Raster data computation (analysis). All the maps are in form of raster images. We are failing from a week to find a proper tool which allows ...
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1answer
273 views

How to convert multiple rasters to new raster (mosaic)?

I want to use Mosaic To New Raster in ModelBuilder. I want it to give me multiple outputs because I have multiple folders with a different number of images in each. Below is the model that I have ...
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2answers
3k views

How do you use GIS to detect percentage of Land Use Change

I am a student in GIS I have a dissertation about land use change. I have questions about using ArcMap 10 for this aim, how can using GIS to detect the percentage of land use change. For example we ...
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1answer
39 views

Symbology Stretch Multiple Raster

I need to change stretch of a raster using properties - Symbology to Minimum-Maximum like image bellow : Problem is I have about 172 raster, is there any way to make this automaticaly change? I ...
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1answer
88 views

Will a WMS handle RPF image scale?

When serving RPF imagery (Raster Product Format) from a WMS, will the WMS handle which layer should be on top? For example, let's say I request layer X and layer Y in some bounding box, and layer X ...
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1answer
12 views

r.series command in QGIS - timeseries

I am using r.series command in qgis. The command is performing correctly, but when I import input raster files, it creates a list in a random order. Sometimes the order of input rasters is essential ...
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2k views

Using polygons to apply unique value to all raster cells within those polygons?

In ArcGIS 9.3, I have a raster file that I would like to "mask" with polygons, giving a single value to all the raster cells that overlap the polygons. How can I do this? Here's a screen shot, ...
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1answer
38 views

Clipping Rasters from Mosaic Dataset in their Original Coordinate System

I am building a large mosaic dataset that contains several hundred rasters, which are spread across three UTM zones. My goal is to be build a tool in ArcMap (most likely within model builder) that ...
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3answers
711 views

What is a simple binary raster storage format which ArcGIS can read?

I have a C++ program that manipulates raster digital elevation models. I have been using ArcGrid ASCII format for results. It is simple to code and gets the job done, but it necessitates a decimal ...
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1answer
48 views

How do I replace cell values of a raster using values of another raster with differing extent?

I have two rasters (raster1 and raster2). The raster1 extent is smaller than raster2. I want to replace the value of raster2 pixels using raster1 pixels. How can I replace the values?
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2answers
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Counting raster points within boundaries in another layer?

I know this question is similar to some out there, but I have tried all the 'solutions' and none of them are working for me. I am using the latest version of Qgis. I have a raster layer with ...
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1answer
20 views

Setting Pixels Band Values

I have a single band RASTER of an area, in which I want to create 360 bands and then assign those bands values from a table. Is there a process for doing this?
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25 views

Rasterizing vector contour data: Python error message

would anyone know why qgis kicks up this error message (image attached) when using v.to.rast.attribute? the rasterise related to a contour set. i duplicated it twice to create 3 copies. the first ...
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40 views

Arcpy raster calculation producing random no data cell in output

I've been trying to get the raster calculation below to work using python: import arcpy from arcpy import env import os from arcpy.sa import * arcpy.CheckOutExtension("spatial") KSat_mm = ...
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1answer
44 views

How to batch generate thumbnails of raster layers with R?

I have been using R to maintain a rather large stack of raster layers (over 700 layers of data for sub-Saharan Africa). Each layer looks as follows ...
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1answer
35 views

How to select a specific area (in a polygon form) determined by some value range in a raster band?

For example, I want create a vector layer with polygons that represents all areas where the elevation is between 500 and 600. Someone has any idea to help me? I'm using PyQgis 2.2.
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38 views

time processing

I am computing NDVI for Landsat TM in grass 6.4.3 in raster map calculator, and time processing is many hours and finally tke message is "failed". trying to find a solution I discovered that it ...
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1answer
28 views

QGis export part of map (box with coordinates) as raster

I would like to export a map of Switzerland (as part of googlemaps) to use as a background for a graph, but I need to know exactly where each corner of the map corresponds to (wrt spatial ...
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2answers
100 views

Calculate Slope Between Pixels Through Time: A Time Series Trend Analysis

I have a 9 year weekly time series (~500 raster grids of equal cell size and extent). I'm interested in obtaining the regression line slope between pixels (Imagine stacking all 500 grids on top of ...
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1answer
37 views

Export Stretch Function values - Arcpy

I'm looking for a way to export Stretch Function values from images that’s stored in a Mosaic dataset. Not values from the whole set, but specific stretch functions per image. The set is stored in ...
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25 views

Disable option in QGIS which picks 4th band as alpha band

Is there a way to disable that function? As somebody who works with 4 band orthoimagery on a daily basis, it is annoying to go to the transparency options every time I load an image to disable the ...
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21 views

Slope regions from elevation points using QGIS 2.0

I am using QGIS to create a layer of slope region polygons (e.g. less than 30% slope, 30-50%, more than 50% categories). My data comes from point elevations and I interpolated using SAGA b-spline ...
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1answer
21 views

DN value from raster to vector tool (QGIS 2.0)

I am using QGIS 2.0 to convert a DEM to vectors, then create polygons of zones of slopes. However, I am unsure of in what units my new "DN" column is. It has lost of precision of z-values from my ...
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Ecoregions shapefiles: subsetting, extracting and summarizing data from raster

I am attempting to subset and project an ecoregions shapefile from : EPA ECOREGIONS my data set is found here: SHAPEFILES and RASTER When I run this code, two major problems occur: 1) I cannot get the ...
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How to perform Raster Reclassification in QGIS?

Is there a way to do reclassify a raster image to Qgis? In Arcgis you can do that in Spatial analyst Tools→Reclass→Reclassify Any ideas?
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Is it feasible to reclassify a raster which has been resampled/smoothed for display purposes?

Background: I have a Google Earth KMZ file which shows ground movements after an earthquake, arranged into discrete classes: From the KMZ file I'm able to download the original PNG images, which ...
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rasterize a geography polygon using postgis 2.1

I am still bit new to Postgis 2.1. I am trying to rasterize a polygon, meaning that I have a polygon of Syria and I want to create an empty raster that contains the shape and geography reference of ...
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65 views

Issues creating slope raster layer from a point layer

I'm trying to create a slope raster layer using QGIS 2.0 on Windows XP. I started with a points layer with the Z elevation attribute. I then used the interpolation plugin to create a DEM. But, ...
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2answers
113 views

Nested loops for raster calculation arcpy

I am trying to figure out a way to input corresponding raster datasets from two separate folders into an equation using arcpy. I think it requires some sort of nested loop but I can't figure out how ...
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2answers
111 views

Replacing raster values in one raster with another raster in QGIS … how to?

I have a raster (DEM) and want to replace a few cell's values with the values from another raster in QGIS. I would have done this with the "over" tool in the raster calculator in ArcGIS. Specifics: ...
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55 views

Need to calculate values for a cell based on surrounding landscape

I have a raster file with the urban development of a county mapped out (values: 1=urban 0=not urban). I also have a raster file with several blocks of forested land, each block of land has its own ...
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1answer
31 views

Passing RasterDataSource object to RasterData object in Javascript API?

I have a GP service that requires a RasterData object as input. The RasterData object should hold a RasterDataSource object, but I'm not sure of the syntax to connect these two classes. The API ...
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How to get RasterToPolygon working

We have a process that is almost working except for this one call ... This is the one tool function that is requiring a FeatureClass and I found code that I thought would work. Unfortunately all I ...
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1answer
27 views

Raster Calculator Syntax - ArcGIS

I'm trying to reclassify a raster based upon two criteria 1. Raster cell on "CBH" is less than or equal to 2 AND "footprint" is not null. Then output raster reclassifies any cell inside this criteria ...
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Minimum mapping unit for raster on ArcGIS

So I have this huge national wetlands raster and I'm trying to set a minimum mapping unit of 5 acres. Meaning I want to delete clusters of pixels that are smaller than 5 acres. But the raster's ...
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65 views

Raster calculation in for loop returning exit code -1

I've put together a python script that does some calculations on rasters by converting them to NumPy arrays, doing the math, then converting them back to Raster and applying all the same spatial ...
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How to draw rotated symbol RASTER type layer in Mapserver?

[PARTIALLY SOLVED]: I was on the wrong track I need to use a UVRASTER, see this part of the docs But doing leaves with with another question about how to get the angle correctly, please see this ...