0
votes
2answers
59 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
409 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 ...
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 ...
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
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
546 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 ...
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 ...