The tag has no wiki summary.

learn more… | top users | synonyms

0
votes
2answers
1k views

Multi-Band (RGBA) into single band raster

I have the raster which contains 4 bands (RGBA), which ilustrates the pupulation (traffic) density. I want to convert it to the simple gridded ascii, however I'm getting in the trouble when I try the ...
0
votes
0answers
24 views

RGB Imagery Layer - Feature Extraction

I'm looking for information on Feature Extraction from the Ordnance Survey Mastermap Imagery Layer. This could be technical information, research papers or just sound advice from folks on this message ...
0
votes
2answers
57 views

From RGB raster to grayscale

I have been searching for a way to rasterize shp files (Unexpected output when using gdal_rasterize) and it worked with a little help. Now, my code is first rasterizing the largest sip file and than ...
2
votes
2answers
395 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 ...
2
votes
2answers
3k views

GDAL: Convert specific RGB (GeoTIFF) color to transparent

I have an RGB GeoTIFF file and I want to convert a specific RGB colour to transparent. I would like to use GDAL for doing this, but external Python scripts are also an option (though I haven't learned ...
0
votes
0answers
53 views

How to change area inside mask to different RGB Value in ECW Format with FME

I have 3 Band RGB ECW Raster files and would like to change all the RGB values within the masked area to 0,0,0. I am using the SpatialFilter to set the masking area and thought that I could use the ...
2
votes
1answer
210 views

How to reclassify a raster (tiff) with multiple bands?

i have a raster file containing information about the windspeed average for the year. My purpose is to reclassify the 15 classes based on their rgb-composite. The color is the only information given. ...
0
votes
1answer
73 views

How to iterate RGB raster layers in ModelBuilder?

I have an RGB raster that I'm calculating color-based indices from. When I do the calculations manually, I can select a certain band of the RGB raster to calculate. I need to do the same operations on ...
0
votes
0answers
44 views

How can I add/define a legend for RGB images in QGIS?

I have a RGB image in QGIS that is the product of some raster analysis (e.g. QGIS's relief operation, results from sound/traffic models) to which I want to add a legend. I'd like to denote several RGB ...
0
votes
0answers
92 views

ArcMap- Create a symbology from RGB with colors name

I have a number of features loaded on a mxd I would like to create a script or model builder to assign each row containing a value in the coloum "ENTE" with a RGB color which must be represented in ...
6
votes
1answer
2k views

ArcMap 10 - Extract raster cells from imagery based on RGB value

I've got some aerial photography (format: IMAGINE Image) which is detailed enough to see to fire hydrants and a shapefile of fire hydrants which was digitized based on some CAD data. My project is to ...
2
votes
1answer
203 views

How to extract vegetation polygons from Imagery using Python?

I have been trying to roughly polygonize vegetation areas from Imagery (RGB). I tried using Iso Cluster Unsupervised Classification (Spatial Analyst) but it is still too detailed for my purpose. I ...
0
votes
1answer
255 views

Basic raster map questions

My bigger problem is to convert a raster map to polygons. I've found some questions that give info and I'm trying to use GRASS GIS as part of that. However, I'm having some basic problems and I can't ...
5
votes
1answer
543 views

How to force RGB in a raster in QGIS?

I have rasters in 1 band 64bits float that represent real data values and for which I can set min and max using the stretch to min and max option in QGIS. I would like to convert these rasters to RGB ...
3
votes
0answers
218 views

How to symbolize vector features using RGB values stored in three fields?

I need to symbolize a vector layer in Arcmap based on RGB (or HSB - can do either) values found in fields in the attribute table. I'm working with up to 10 different datasets, each with over 100 ...