similar to: Tif image to 8bit colour matrix.

Displaying 20 results from an estimated 4000 matches similar to: "Tif image to 8bit colour matrix."

2009 Jul 15
1
Read PNG file and display with more than 256 colors RGDAL
Hello list I am trying to use a Googlemaps tile (png file, 640 X 640 px tile) as a background to a plot and have been using the rgdal library to read in the PNG file (modified from code in the RGoogleMaps package). This works OK. My problem is is that the SGDF2PCT function in rgdal seems to be limited to 256 colors and this is introducing (I think) some degradation to the image which appears on
2012 Oct 18
2
Re-projecting geotiff
Dear R users, I'm currently trying to re-project a geotiff in another coordinate system. For instance, I have a tif image in UTM 19 zone which I would like to reproject into UTM 18. I was wondering if it was possible in R. Furthermore, I looked into 'rgdal' package, but I can't really find out if I'm doing the right thing. So far, here is what I'm doing: library(rgdal)
2012 Mar 27
1
Rgdal package - get information
> > Hi, > > I used > GDALinfo("MOD13Q1.A2001049.h13v11.005.2007002215512.250m_16_days_EVI.tif") and > got the results: > > rows 10 > columns 11 > bands 1 > origin.x 150701.4 > origin.y 7744897 > res.x 250 > res.y 250 > ysign -1 > oblique.x 0 > oblique.y 0 > driver GTiff >
2007 Mar 03
1
R software to place points on Yahoo maps
Is there any R software that create an image from Yahoo maps together with points of known UTM coordinates (or lat/long marked? Note that my region of interest is not covered in sufficient detail by Google maps. It actually does not have to be Yahoo maps as long as it has sufficient coverage of my region but that's the one I have found with coverage of my region. The scale I am interested in
2007 Sep 06
1
write geotiff with projection - RGDAL package
Hi, Doing more search i've discovered package RGDAL that can write a geotiff file with projection. I saved a geotiff file in UTM projection and if i read the file back in R and check the projection seems that everything is OK. But if i load the file in ArcGIS (ESRI product) i get the warning that the file is missing spatial reference so it cannot be projected, but it is displayed correctly.
2006 Nov 28
2
Aligning aerial photographs and maps
I have read in Paul Murrell's book R Graphics about how to use a bitmap as background for a plot (page 107). Also, I routinely use function read.shape() in package maptools to read maps in shapefile format. Now, I would like to overlay an aerial photograph in .jpg format and a map. I think I could do the alignment manually for each case, but wonder if there is a better, automated way. I notice
2007 Sep 05
1
geotiff or tiff files with world files
Hi, I have a matrix of data which i can vizualize as an image - for example. I would like to save this image as a geotiff file or at a tiff file with a world file which holds the projection of my data (ultimately the data represent a map of some sort). I know i can save the data as an ESRI grid, but i am not interested in that. I wonder if anybody knows about any code which will help me do
2007 Sep 20
2
Superimposing vector polygons over raster grid in a plot
Hello: I would like to superimpose vector polygons (state outlines) from a Shape file on top of a satellite image, imported into a SpatialGridDataFrame from GEOTIFF via gdal_translate and readGDAL. When I plot polygon and point shape files in R, into SpatialPointDataFrame and SpatialPolygonDataFrame, the two feature sets line up geographically, so it seems logical that a SpatialGridDataFrame
2012 May 08
2
PPM to BMP converter
Dear all, Several days ago, I posted How to write a bmp file pixel by pixel. Instead of bmp, I succeeded in writing a PPM file by using the pixmap package. Thanks for the hint generously provided by Uwe Ligges. Now I have a new question. How to convert a PPM file to BMP file in R? I know I can do this in photoshop or by some other softwares, but I think if I Can do this in R, that
2008 Jul 01
2
Are centre coordinates or upper left corners used of x, y for SpatialPixels?
Dear all, I'm working with satellite images in R and plotting them via the code below. I was wondering whether coordinates (spatial["x"], spatial["y"]) are used as centre coordinates of the pixels in the GRID? In this script; spatial["x"] & spatial["y"] are the centre coordinates of the satellite image pixels. I'm asking this because some
2010 Sep 24
2
Reading in .aux (ESRI raster files) into R
Dear All, I'v tried to read in data in numerous ways including:- Spain10km<-data.frame(readAsciiGrid("F://RMap//sp10kpointid1.aux")) Error in readAsciiGrid("F://RMap//sp10kpointid1.aux") : object 'cellsize' not found In addition: Warning message: In readLines(t, n = 6) : incomplete final line found on 'F://RMap//sp10kpointid1.aux'
2011 Nov 24
1
readGDAL or raster for reading bit map files
Dear all, I have asked yesterday of how I can read a simple bitmap file in R cran. I was suggest to use either readGDAL or raster for loading my bitmap a. I have done it with readGDAL like     store<-readGDAL(fname='lena256.bmp')     and it works,... but it converts my matrix-like notion of a bitmap to a large vector b. Raster also returns a class that I can not understand. So 1,
2009 Jul 16
2
Problems generating image from tiff file
I imported the attached tiff file and converted the coordinate system to long lat and graphed it: californiatiff<- readGDAL("california1.tif") proj4string(californiatiff) > rasterprojection <- spTransform(californiatiff, CRS("+proj=longlat") however, when using the plot command for rasterprojection, I get a blob. I can see the outline of the state of california and
2008 Jan 11
2
clipping a large image on R
Dear all, I have a so large image (43,000 x 18,000 pixels) and I need clip this image with a smallest one (1000x1000 pixels). I can read the second image using rgdal package. But the first image can´t be read on my system because if memory limitation (I have about 2GB availabe). So I would like hear from you if anyone have some suggestin in this regards. I have also ArcGis 8.6 ans Erdas 8.3
2012 Dec 26
1
Change class of elements in list
Dear R users, I have a list of objects of type "im" > mylist$sp1 $sp2 $sp3 and I want to convert them to a list of objects of class "SpatialGridDataFrame" This works for a single object of class "im": a <- mylist$sp1 b <- as(a, "SpatialGridDataFrame") Then I want to write each element in the new list as a TIFF file, with the name of the elements
2010 Mar 19
1
error in map library
Dear Ruser, > > > I am trying to use the map library. But unfortunately I am facing the > warning message above: > Warning message: > *In readGDAL(destfile, silent = TRUE) : GeoTransform values not available > * I want to use that library because I intend to plot some station in a Brazilian map. I really appreciate any help. > > ===here what I was testing========
2008 Nov 05
1
Using RGDAL to "copy" header information...
R-geographers... I'm trying to solve a problem to implement a line-by-line tiled processing using RGDAL (read 1 line of an image, process the one line, write one line of the image to a binary file). Everything except for the final step I'm able to do using a combination of RGDAL and r-base commands. Below is the basic structure, the input file "elev" can be any image file
2010 Sep 25
4
Help required
Is it possible to read jpeg files into R? If yes please guide, Thanks.. I tried to search many time but failed to do. Thankis in advance.. with Best Regards, Malik Shahzad Visiting Researcher National Institute of Informatics (NII) Tokyo, Japan Doctoral Student Asian Institute of Technology (AIT) Bangkok, Thailand +66-8-7676-5616 [[alternative HTML version deleted]]
2017 Sep 06
2
rgdal error when trying to import raster
Dear useRs, I am trying to import a raster with the line: nlcd <- raster("/home/jpolo/NRI/nlcd_nri5000.tif") And I keep getting an error like this: "Warning message: In library(package, lib.loc = lib.loc, character.only = TRUE, logical.return = TRUE,? : ? there is no package called 'rgdal' Error in .rasterObjectFromFile(x, band = band, objecttype =
2009 Aug 24
1
Import/export ENVI files
Hi! I'm a beginner with this webpage so, I don't know if I'm sending my question to the correct site. Anyway, I'm working with R and I need to import and export ENVI files, (*.HDR files). A colleague told me that there is a package to import/export envi files but I haven't found that package, so does anyone know something about this? thank you so much :) . Ciaooo