Imagery refers to raster based datasets acquired from sensors on satellites or aircraft.

learn more… | top users | synonyms

3
votes
2answers
516 views

Tasseled Cap Transformation Rapid Eye

I want to do tasseled cap transformation on rapid eye data. the main question would be about the parameters which are used. Somebody has a suggestion? A short update concerning this attempt to ...
2
votes
1answer
32 views

Primary and secondary data

If I am creating data from satellite imagery, is this classed as primary or secondary data? If I am creating slope data from a DTM, is this then classed as primary or secondary data?
0
votes
0answers
32 views

How do I convert a false colour image to a pseudo colour image in QGIS? [closed]

I have geotiffs developed from a Canon S110 NIR camera (see https://www.sensefly.com/fileadmin/user_upload/documents/manuals/user_manual_s110_v3.pdf). This sensor records red, green and NIR bands. ...
1
vote
1answer
36 views

gdal2tiles georeferenced image as overlay not working

Ive been looking for a solution to my problem for some time now. I'm using gdal2tiles-leaflet to create tiles for my Leaflet application. The images i use are GeoTiff's with the embedded projection ...
0
votes
0answers
23 views

0.5m resolution up-to-date images for Iraq

I use TerraServer for general keeping up to date on infrastructure projects. TS, however, don't exactly offer the latest images - some are 12 months old, some even older. A small saving grace is that ...
0
votes
0answers
6 views

google maps engine connector

I am trying to use google imagery in QGIS through the Google maps engine connector plugin. I relatively new to QGIS and need some help. What I want to do i use the google maps in QGIS and then print ...
0
votes
1answer
27 views

How to create grid from 2 separate images of latitude and longitude

I have two separate images of latitude and longitude, and want to create a grid from them so I can assign it to my Non-Geo referenced file... How can I create it, particularly in Matlab... But other ...
2
votes
1answer
73 views

Why does the peak of a mountain appear bright on Radar images

Why does the top of a mountain appear bright on a SAR (radar) image. I know that the peak of a mountain is subject to a layover effect, thus appearing closer on the radar image than the bottom part of ...
1
vote
0answers
26 views

Saving a TIFF file with band names

Does anyone know if it's possible to add a TIFFTAG when saving a tiff file (I'm using the C/libtiff interface) that will give a name to each band? Some kind of per-band TIFFTAG_IMAGEDESCRIPTION is ...
1
vote
0answers
41 views

How to align hundreds of rasters quickly

I'm hoping to accurately align hundreds of aerial images that are slightly off-kilter. The images cover the same area on different dates (several acres). They contain identifiable features around ...
1
vote
1answer
65 views

Does anyone know a way to do a supervised classification on a google maps image to show only hedgerows?

I would like to then use the hedgerows by bringing it into QGIS as a layer. I need to know what software to use and the method to make such a layer? I would like to use a google earth image in Grass ...
1
vote
1answer
42 views

How do I convince gdal2tiles to output pngs with transparency?

I have a tiff that was created with Pix4dmapper. This tiff has coordinates embedded (as seen in the logs below) (I think that makes it a geotiff?) as well as a tfw file associated with it. Opening ...
2
votes
1answer
52 views

QGIS: raster image georeference and overlay

I've created a grid and points in QGIS which I used to survey. Using a test image at the moment and I'm trying to fit this image as an overlay within a boundary. When I insert the image it has a white ...
1
vote
0answers
79 views

USA Historical Satellite Imagery for an Online Application

I am looking for different options to add historical satellite imagery to our online-based application. We currently incorporate Bing Maps into our application, but cannot get historical imagery. I ...
0
votes
1answer
27 views

comparison of atmopsheric correction methods

I have noticed that dos methods for atmospheric corrections are in the section of radiometric correction (i.toar) on grass gis.Does that means that dos is a method doing radiometric and atmospheric ...
1
vote
1answer
68 views

How to calculate raster statistics for each band in qgis

i need to calculate raster statistics for RGBN (4 channels, multiband image) rasters in QGIS. In Arcgis if you use "calculate statistics" in Arcatalog, statistics are calculated for every image band. ...
0
votes
0answers
19 views

image files and metadata

When writing metadata for .img files stored on disk, as opposed to a raster catalog, raster field names are shortened to 10 characters, because the vat.dbf file is created and read (by arc catalog ...
0
votes
0answers
28 views

I am looking for Thermal IR Photography with 1 m resolution?

I am looking for thermal IR photography with 1m resolution? It needs to be recent or maybe a company in western Canada that can fly a mission like this. Satellite or flown photos both work, I am just ...
0
votes
0answers
30 views

remove black margin of georeferenced image before overlay to google maps

i used envi to georeference satellite imagery. then I tried to overlay that geo image to google map. all fines BUT the black margin appears on the map. is there any way to git rid of that black ...
4
votes
0answers
172 views

Which remote sensing satellite is best used for chlorophyll mapping?

Location of my research are reservoirs which have an area of 47 and 62 km2. I need a better image resolution than Landsat(Pan).
2
votes
0answers
132 views

Good GPS navigation app for iPhone with downloadable OFFLINE maps?

I am looking for a good GPS navigation app for my iPhone that will work away from wifi and cell coverage (GPS only) and thus allow me to download offline maps. Paid app is OK. Must Have features: ...
0
votes
1answer
60 views

Satellite Images for the Mediterranean Sea Oil Spill

I am looking to obtain free satellite images to detect oil spills in the Mediterranean sea. What sensors would be most appropriate for this task and where can I download this type of data?
3
votes
2answers
133 views

Is it possible to highlight water steam sources on Landsat 7 image?

I am trying whether it is possible to view hot steam sources like power plant cooling towers and resulting cloud using satellite images. I was advised to try Landsat (needed free data for initial ...
2
votes
3answers
55 views

Saving extent of satellite imagery in ArcGIS Desktop?

I'm using 50cm imagery for the whole country of South Africa, which make zooming and panning painfully slow. Can I save imagery for just the area I am working with (ie. data frame, city, province)? ...
-1
votes
1answer
1k views

how to stack landsat 8 layers correctly? [closed]

i downloaded a landsat8 satellite image from USGS, it was separated into 12 layers. So, what i would like to do is to stack some of them. To do that, i am not sure which layer should be excluded from ...
5
votes
2answers
508 views

Extract certain area of contours/satellite images

I have 2 satellite images (jpeg2000 format) and 2 xyz-files from the same area. I am trying to extract certain region from the area including contour lines and the satellite image in order to import ...
1
vote
3answers
97 views

Free download NDVI images or raw satellite images

Could anyone provide a site to download NDVI images or raw satellite images of Sri Lank (Asia)for free for me to calculate the NDVI.
27
votes
7answers
3k views

Work flow for georeferencing imagery using open source tools?

Does anyone have a recommendation for a work flow for georeferencing high resolution aerial photography using open source tools? Comparison of user friendliness and robustness between Quantum GIS ...
2
votes
2answers
1k views

How to compress raster image for publishing?

I have a (8-bit) satellite image that is e 6 gb. Is there a way I can compress the image smaller size without losing the quality? Format: .tif Reason: After publish the image, I notice a higher usage ...
1
vote
0answers
30 views

How do I use Multispec for Landsat data?

It seems that I only can use the Clustering if I want to cluster only one band data.. If I open up more than 1 band (in one image), the cluster toolbar is disabled? optional: Is there any free ...
0
votes
1answer
55 views
0
votes
0answers
24 views

Band values after TOA reflectance calibration of WV-2 exceed 1

I use custom python-GDAL script to calibrate WV-2 scenes to TOA reflectance accordingly to 'Radiometric_Use_of_WorldView-2_Imagery'. Here you are a histogram example with the pixel values of the ...
1
vote
2answers
128 views

Where to download 4-band NAIP imagery for California?

I've been trying to find orthoimages with 4 bands for a couple of counties in California. I managed to download some from the GeoSpatial Data Gateway from the USDA (NRCS), but they all only have 3 ...
2
votes
3answers
2k views

Where to download 4 band NAIP imagery?

I seem to recall USGS Earthexplorer providing current and historic 4 band NAIP imagery over the last few years. It appears that these data have been migrated to the National Map. However, the ...
1
vote
1answer
88 views

ESRI World Imagery (for Export)

I would like to download some of the ESRI World Imagery using this however when I try to add the layer to an online map I get "The layer, World Imagery (for Export), cannot be added to the map". I've ...
2
votes
1answer
44 views

Georeferencing in R Based on the Four Corners

I have a raster image (photograph) that was taken from a helicopter. Along with that raster image, the system also tells me the positions of the four corners of the image in a different file. I have ...
0
votes
1answer
68 views

Satellite imagery alternatives for land use/cover classifcation

Apart from Landsat imagery, which other satellite imagery is good for land use / cover studies and can be obtained free of charge?
0
votes
0answers
91 views

read tiff to bmp in c# got only white image

i want to convert a tif image to bmp i was following tutorial in https://trac.osgeo.org/gdal/wiki/GdalOgrCsharpRaster but i dont get an image i want to see the code is : // Creating a Bitmap to ...
5
votes
6answers
7k views

Removing No Data From Raster (*.sid) using ArcGIS Desktop?

I have an Image.sid that has a white border which is No Data. I've tried using Clip Raster Tool with no success. I've also changed the symbology value for No Data to be transparent. I'd like to ...
1
vote
0answers
47 views

ArcGIS Server Image Service from Mosaic Layer

I have successfully created an image service from a mosaic dataset using NAIP imagery. I would like to create another image service that displays the same area in NIR (4,3,2). I have created a mosaic ...
1
vote
0answers
107 views

Stacking Band ratio on Landsat 8?

I have a question about Landsat 8 I am going to work on... I am thinking about stacking all the bands however there are 15 m, 30m, and 100m Do you stack all together ? This is to give the end-user ...
1
vote
2answers
29 views

Limiting Imagery to a Certain Area

I have a layer that shows some imagery in Ontario. I would like to get rid of the imagery that I don't need, because I only need it to be in 6 squares that I have. Is there a way to restrict the ...
2
votes
0answers
68 views

How to serve an image layer with tilestache

I have some .png images with associated .wld and .tfw files. I'd like to display this in OpenLayers, and I already have a Tilestache server running, so it would be good to leverage this. OpenLayers ...
1
vote
1answer
642 views

Projection to use with satellite image from Google Maps / Earth

I'm very new to anything concerning GIS so please forgive me if this question has been asked before, but I assure you, I've been trying to find an answer for quite some time now. Of course it is ...
0
votes
1answer
178 views

Empty raster returned after GRASS i.atcorr with Landsat8 data

I've searched at length on previous forums but no solution seems to work for me. I'm trying to run the i.atcorr module on GRASS (version 6.4.3 on a Macbook Pro, Mavericks OSX) with Landsat8 imagery. ...
2
votes
0answers
38 views

Why did my footprints build failed?

As I am trying to add raster to my mosaic dataset and were able to see them and now all of my raster are not showing. Why did it could not build a footprints ? I have tried everthing to get them ...
0
votes
0answers
43 views

White box problem

As I am trying to work on getting this problem done , I am using Mosaic Dataset for the whole state of New Mexico using our NAIP ...now the problem is that I could not get rid of the white "box". I ...
1
vote
4answers
3k views

Free Imagery WMS Feeds in QGIS

I was wondering if anyone knows of a free WMS of imagery that I could use within QGIS. The imagery does not have to be high resolution (Blue Marble even). I would like to have a base imagery feed ...
0
votes
1answer
50 views

Mosaic dataset gives me some blocks

as I am trying to mosaic NAIP into mosaic dataset and ended up like this with the block. How do I remove the blocks ? Does anybody have a suggest for me to fix them ? I am using ArcGIS 10.1 SP 3 ...
3
votes
5answers
5k views

How to redefine the nodata value into zero in QGIS?

I have an image which i cliped with an AOI polygon. The contour area was set to pixel value = 0 and I have a nodata value of -32768. I want to redefine the nodata value into zero. I used to do this ...