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

learn more… | top users | synonyms (1)

0
votes
1answer
17 views

how can we convert vector data to raster data in geotools

In my project iam able to open and save shape file. I want to convert this vector data to image format as a tiffimage plese help me the procedure to do the same.
0
votes
0answers
37 views

rasterize table polygon postgis 2.1

I would like to rasterize a postgis 2.1 polygon table, but I don't undersand how to create the SQL function syntax for ST_AsRaster. My vector table has 3 fields: gid, recharge, and geom. The SQL ...
0
votes
1answer
50 views

problem in scale of projected raster

I have a shapefile (my basin limit) and one raster file that I projected it to the shapefile coordinate system and set its cell size to 1000m(area=1Km2). my basin area is 5400 Km2 and it should ...
1
vote
2answers
58 views

Sum values within one raster (25m) using another raster (1km) ArcGIS Desktop 10.2

I am summarizing some population data using a 1km raster overlay. I converted population data, polygon layer, into a 25-meter raster that contains the value for population/m^2. That value is then ...
0
votes
1answer
37 views

Extracting info on polygons from underlaying raster layers

In ArcGIS 10.1, I have two layers: 1) raster of Topographic Wetness Index 2) vector layer of polygons representing soil types I am wondering how to accomplish what I am after, that is to get ...
1
vote
1answer
36 views

Export a large raster to a comma or tab delimited text file in ArcGIS 10.2 for Desktop

I have a large raster with multiple attributes in 200-meter cells, and I would like to export this to a tab or comma delimited file which contains the X,Y coordinates and all of the attributes. If ...
1
vote
1answer
21 views

How to change the symbology on many image files within a group?

I have a group of raster images from lidar data (so a DEM). When loaded in, they all have different symbology - so their color scheme and color ramp are all different. I would like to create a group ...
0
votes
0answers
23 views

GeoTIFF Mosaic/Crop/Translate: Easiest Method in QGIS?

I routinely have to mosaic multiple GeoTIFFs together, extract a rectangular area, and save that area as a JPG with a world file. Typically I've been using commercial software for that (Geographic ...
3
votes
2answers
99 views

Creating raster pinned to cartesian coordinates using ArcGIS for Desktop?

I'm looking to create a raster such that the edges of the raster are aligned perfectly with the cartesian coordinates of the underlying projection. I am using a custom Lambert conformal conic ...
4
votes
5answers
135 views

How to group individual groups of pixels into a single class

I have a raster image with certain pixel groups of equal area. Each group represents a single house. I want all the pixels near a group of houses to have the same pixel value, i.e., I want to name ...
0
votes
1answer
47 views

How to convert raster negetive pixel value to positive

I was working on ground water Level. I used raster math minus function and the Output raster grid data contains negetive cell values. ma resulting raster contains values ranges from High : 0,187477 ...
5
votes
4answers
372 views

What satellite imagery would help to show spring locations?

I've got lots of tiny streams on a hydrography shapefile. Historic texts indicate that certain ones have headwaters at "sources" or springs, and I want to try to find these. Browsing the historical ...
0
votes
0answers
23 views

QGIS-Merge or create virtual raster files without losing definition?

I am new to QGIS and relatively new to GIS (so please be aware I am not that familiar with a lot of technical terminology). I am trying to merge several tiff files as either a virtual raster or a ...
0
votes
2answers
65 views

Error in which.max() : not yet implemented for large objects in R

I am going to create raster by Julian day that observed maximum value of NDVI within a single year. Actually, I want to know which julian day (or raster) has max value in each cells and get result by ...
0
votes
1answer
43 views

Selecting raster data by location: for raster and feature class data

I have rasters covering certain spots in my environment, I'm looking for a way to extract the values which occur at locations which are defined by a selection of feature layers. I've tried with the ...
2
votes
1answer
33 views

Problems merging OS Terrain50 tiles i.e. gaps at small scales after using “Mosaic to New Raster” Any ideas?

I downloaded the OS Terrain 50 dataset in ascii format, then unzipped all the folders and searched for all *.asc files. I then copied and pasted these into a new folder, so that they could be easily ...
0
votes
2answers
69 views

How to create raster map by day that observed maximum NDVI from multiple raster data in R?

I have 11 NDVI raster data, representing single summer. I want to create raster by day (Julian day or name of raster) that observed maximum value. In other words, I want to know which day (which ...
3
votes
2answers
63 views

“Levelling” elevation data coinciding with polygon?

I have a shapefile containing building geometries (polygons) and a elevation dataset. The elevation data doesn't perfectly match the buildings. I want to "flatten" the elevation data so that ...
1
vote
1answer
62 views

Fix Black Border in Python Batch Raster Conversion

I have a Raster image like this as you can see the road are not connected between 2 raster (up and down) its because the scanned raster use different projection (dgn utm 50s) than my data frame (utm ...
0
votes
1answer
69 views

QGIS Scripting problem updating contrast enhancements for raster layers using bandStatistics

Found this function to update statistics for a raster layer : rlayer.setContrastEnhancement(QgsContrastEnhancement.StretchToMinimumMaximum, ...
0
votes
1answer
22 views

Overlaid raster gets shifted around when printing to pdf or when resizing graphics device with mouse

I've spent the past couple of days learning how to use the maps, raster, and rgdal packages to create nice images, but I'm running into trouble when trying to make pdf's for actually presenting. I'm ...
3
votes
3answers
171 views

Las to bare-earth DEM: average points spacing and cell size

I am using ArcGIS 10.1 to generate a DEM (bare earth) from LAS dataset. To accomplish this, I use 'Las Dataset to Raster' tool as described in Esri website. I have read here and there in the web that ...
1
vote
1answer
57 views

Calculating field length in certain directions (raster)

Currently I'm working on winderosion. For my purpose I like to calculate the length of agricultural fields in certain wind direction. I would like to do it for raster. To be more precise: I have ...
0
votes
1answer
45 views

netcdf daily data to monthly raster layers

I have a netcdf (.nc) file of 95GB which consisted of daily data for a 50 years period. I tried to process this with ArcGIS (Multidimension tools – MakeNetCDFRasterLayer command) and it was not ...
0
votes
1answer
42 views

Are there another way/tool as GDAL/ERDAS-API to convert a raster to ECW?

I am looking for a tool to convert raster (TIF, JPG) to ECW. I found this two year old question/answer How to convert orthophotomap to .ecw file? The answer is to use GDAL with an ERDAS SDK. I checked ...
0
votes
1answer
23 views

GRASS raster map types: UInt16 and Float64

i am in the processing of using r.out.gdal to export DEMs from GRASS into QGIS this is the output of the first try: using UInt16 as the data type. r.out.gdal input=DEM0maslTopog@UTM_35S ...
2
votes
1answer
29 views

Stacking overlapping rasters, keeping cell values on top?

I have a land cover classification that consists of three files. One file is the LCC for the western half of my study area, another covers the eastern half (these two overlap in the middle), and the ...
1
vote
1answer
28 views

Aggregate the raster from the Combine Tool in Spatial Analyst--->Local

I have a raster file created through the Combine tool (Spatial Analyst--->Local). The attribute table is showed below. Its resolution is roughly 10m. I would like to aggregate it to 50m with each ...
0
votes
0answers
41 views

How to calculate a population weighted centroid using a raster and shape file in QGIS?

I am very new to QGIS so please help me with a step by step answer. I have a raster file with population count and a shape file based on a large population and shape file. I have successfully created ...
1
vote
0answers
20 views

Weekly raster data for temperature and precipitation in US

I am looking for weekly raster data for US for temperature and precipitation. All the major datasets PRISM, WorldClim etc. are either on a monthly scale or daily scale. I was wondering if anyone has ...
1
vote
1answer
44 views

Alternatives to bilinear interpolation for raster extraction in R

I have a set of coordinates for which I want to extract temperature values from a raster. I am using the extract function from the raster library in R. Looking at the interpolation methods, there are ...
0
votes
0answers
5 views

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.
0
votes
2answers
51 views

Is it permissible to redefine raster resolution (not resample!) in order that it be included in a SDM?

I'm fitting a SDM using R. A requirement is that all environmental predictor layers have the same extent, origin and resolution. I have high resolution bathymetry data (25m) that I will resample to ...
2
votes
0answers
37 views

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. ...
1
vote
0answers
27 views

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 ...
0
votes
1answer
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. ...
0
votes
0answers
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:
0
votes
0answers
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 ...
0
votes
0answers
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.
0
votes
1answer
29 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 ...
-1
votes
0answers
31 views

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 ...
0
votes
0answers
30 views

qgis's georeferencer renders my white map with a translucent blue tint, can I prevent this?

I'm running QGIS 2.0.1-Dufour on MacOSX and when loading a PNG or TIFF into qgis as a raster its always getting rendered with a blue tint. Here's what it looks like before being loaded into QGis's ...
0
votes
0answers
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 ...
1
vote
3answers
134 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 ...
0
votes
1answer
79 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 ...
2
votes
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 ...
0
votes
1answer
33 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 ...
0
votes
1answer
15 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 ...
0
votes
1answer
39 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 ...
1
vote
1answer
55 views

Is there a way to write single bands raster from multi-band layer faster in r?

I have 1000 multi-layer rasters and have to export each separate layer to a tif. Some friends recommended R to do the job. I used the following code: library(raster) namesVector<- c("layer1", ...