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10

Well, I found the answer. Esri did in fact answer this with an in depth presentation at the 2010 San Diego User Conference called "Managing Imagery and Raster Data in ArcGIS". Here is the link for anyone else who is interested: http://gis.idaho.gov/portal/pdf/Framework/Imagery/ManagingImageryRaster.pdf My short summary of this is: Raster Catalog is on ...


6

Another option is to build a Virtual Raster. You can perform this using GDAL, FWTools, or QGIS. Essentially, a virtual raster will make the mosaic, but as a pointer file, that brings in all the imagery. The file size stays relatively small, and the performance is good. I am using it to mosaic 5cm imagery, and I like the results.


5

The issue here is that mosaic and do.call are expecting a raster object in the list and not just character names of the raster that is contained in the "rasters1" vector. You are, in effect, asking to mosaic a name in a vector and not a raster object. # Create some example data require(raster) r <- raster(ncol=100, nrow=100) r1 <- crop(r, ...


4

First, you are using R. R Studio is just an IDE for R so in the future please make this an R question. I will warn you that working with HDF files in R is a pain. In theory GDAL supports HDF5 so one could use readGDAL in the rgdal package. Depending on the source of the data readGDAL has a high fail rate making it less than reliable. Historically, there ...


4

I noticed the Mosaic To New Raster tool has a Mosaic Operator setting. The default is LAST, which states the output cell value of the overlapping areas will be the value from the last raster dataset mosaicked into that location. Settings are FIRST, LAST, BLEND, MEAN, MINIMUM, and MAXIMUM. I would try other settings or reorder your rasters in the Input ...


4

I recommend creating a mosaic dataset within a file geodatabase. There are many advantages of working with this type of data model. For one, you can modify properties of the dataset once it is created to enhance rendering. You also have much finer control of how these data are served compared to a stand-alone raster dataset created using mosaic to new ...


3

The simplest way I can think of is to take the merged raster you have just made and save out the red band (perhaps using gdal_translate and the -b switch). Alternatively you could use QGIS' raster calculator to save only the red band as a new raster.


3

FME RasterMosaicker can accomplish this: You will have to modify these setting to suit your sampling and Interpolation. You should be be able to achieve something like this if your aerial photo have been ortho-rectified: It might take a few goes- best advice is to try a sample of 3-5 adjoining images and test. source of image (safe.com) and more ...


3

In addition to @Ryan Garnett answer, you can convert the VRT file to BIGTIFF using gdal_translate if you absolutely need a unique file (this is often not necessary as most software can read vrt's). Just make sure that you use gdal_translate -co BIGTIFF=YES -co TILED=YES source.vrt result.tif if your tif exceed 4 Go


3

Try gdal_merge. You can grab the GDAL framework from William Kyngesburye's website. Instructions for utilizing gdal_merge can be found here.


3

There is some good description of NoData in raster datasets in general here. Otherwise, I'd suggest using the Define Mosaic Dataset NoData GP tool.


3

There seems to be two camps about this one. Some prefer to mosaic before classification, others prefer to classify the images before mossaicking. Personally, I would classify the images first, then mosaic them. Have a look at the discussions on this page and you'll find arguments for and against both methods. Generally, they state that you should ...


3

I ran across this mosaicing the True Marble imagery as well, though I used gdalbuildvrt and then gdal_translate. From memory, the recalcitrant tiffs are stored as a single band with a color table. Just convert them to 3 band RGB with gdal_translate: gdal_translate -expand rgb TrueMarble.250m.21600x21600.B4.tif TrueMarble.250m.21600x21600.B4.RGB.tif


3

There is a GRASS GIS 7 Addon, i.histo.match which performs histogram matching on the given input images. The histogram matching method is based on the method Cumulative Distribution Function (CDF) of two or more histograms. For RGB images you will mosaic them color by color. If needed, a post-mosaic color optimization can be achieved with i.landsat.rgb (it ...


3

You have to enter the parameters in the correct order when using Python. From the ArcGIS 10.2 help page, the following is the correct format: MosaicToNewRaster_management (input_rasters, output_location, raster_dataset_name_with_extension, {coordinate_system_for_the_raster}, {pixel_type}, {cellsize}, number_of_bands, {mosaic_method}, ...


3

A successful workaround was to create a new file geodatabase, and write the mosaic image to this - the gap is now gone, with no other changes to the code. This may be a bug, or perhaps there's a problem with using PNG files as the output?


3

I support the answer by radouxju, but would like to add: As you have chosen to do this in chunks (good idea! you can process multiple chunks simultaneously) I recommend using an overlap of ~1k with your tiles. You have not elaborated on how you create the DEM from LiDAR data but lets assume that you are using LiDAR->MultiPoint->Terrain->Raster DEM ...


3

Your best bet would be to mosaic the raw red band and near infrared band images from which the NDVI images are derived. There are techniques for creating seamless mosaics for images, e.g. through the use of histogram matching and feathering techniques. For areas of overlap, the feathering method will calculate the output value as a weighted combination of ...


2

I would advise against image processing with R. Rather, I would revisit mosaicing your imagery with ArcGIS. I used the following model recently to mosaic approximately 40 1m CIR raster images into a 25 GB mosaic (shown below). ArcGIS is definitely capable of large scale processing if you do it correctly. A few ideas: Make sure to set the raster storage ...


2

You can specify the parallel processing factor in the Mosaic environment settings (See attached image), which is new to ArcGIS 10.1 SP1. However, be cautious with this method since ESRI's documentation is very minimal and bordering on cryptic. I would do some timed runs (and share your findings here) before implementing these environment settings on very ...


2

I have a solution! It IS because of the old and infuriating GDAL upside-down export to GeoTiff (see my comments above)! Before anybody tells me that this has been fixed - I agree it does appear to be fixed but I was using a mixture of data converted with a older version of GDAL about 4 years ago and data I converted with the latest version of GDAL about 3 ...


2

I am now using an python+arcpy script for adding the raster to the Mosaic DataSet and then updating the value in the time field. For this, I am using some Python time/date time Manuipulation to get the correct expressions. My code is as follows: import arceditor import arcpy import datetime import time #time manipulations n=datetime.datetime.now() ...


2

Sadly, no. Not in 2.0. 2.1 should provide significant performance improvement over 2.0. No matter what you attempt in the database with 2.0, you are limited by the number of times the raster objects are serialized/deserialized. PostGIS 2.1 should be going beta in the next week or two (hopefully sooner than later).


2

Merging is combining several (usually vastly overlapping) rasters into one either single-banded or multy-banded raster wich area isn't much bigger then the area of any original raster. Its purpose, well, is to get one raster out of many. Mosaicing is assembling of several adjusted (or slightly overlapped) rasters into the set of non-overlapping rasters or ...


2

Merge is usually used to refer to the combining vector data whereas mosaicking is used when combining raster data. At least that's how the terms are used with ArcGIS and QGIS.


2

You need either an ArcEditor or ArcInfo license level to use the mosiac tool. You can use ArcGIS Adminstrator to verify and change your license level. First close ArcMap, then go to Programs>ArcGIS>ArcGIS Adminstrator. Select the Desktop folder, then check your level on the right. If ArcView is selected you will need to change to an ArcEditor or ArcInfo ...


2

As BradHards noted, "pleasing" is subjective. That being said, two methods come to mind: (1) Create a new constant raster, erase the islands (assuming you have a vector layer for their boundaries (if not, create one)), and calculate euclidean distance away from the island shores. ESRI has a white paper outlining this method here, although the general idea ...


2

This is more of a database issue than a GIS one. It's counterintuitive, but you need to increase allocation in order to delete data. If you add a new file to the filegroup, there should be enough space to drop the raster normally. Another option is to TRUNCATE all the tables which participate in the raster, but depending on which filegroup has been ...


2

When you move any rasters referenced by a mosaic dataset, including overviews, you must repair the paths locating these rasters.



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