The field of raster image processing

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2
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1answer
32 views

Mosaic Imagery using GDAL Edited

I have a couple of large sets of imagery I need to mosaic using GDAL. The sets are currently in tiff format with 18 tiles totaling about 20gb in size. I have attempted to mosaic using both the ...
1
vote
1answer
34 views

Calculating NDWI in Erdas IMAGINE 2014

I'm using MOD09GQ product of MODIS to calculate vegetation indices in Erdas 2014, and I was able to extract NDVI using Erdas Model Builder. What is the formula I should use in model builder for ...
0
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1answer
24 views

Conversion of multispectral image to grey scale

I have a composite with four bands NIR, Red, Green and Blue. I would like help on which weight values to use when converting it to a single band which will then be used to classify vegetation. I am ...
0
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0answers
28 views

How to transform ENVI Hdr to PNG using GDAL?

I am trying to transform a ENVI Hdr image into a PNG (or other RGB image format) in order to visualize this image. I am selecting the three default bands (55, 41, and 12). I am using GDAL by using ...
0
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1answer
35 views

Is there any comprehensive book or online instruction on image segmentation techniques?

I'm looking for a source to learn theoretical basis of image segmentation techniques thoroughly. The desirable book, or other kinds of source you may know, should cover the techniques that are more ...
4
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1answer
76 views

Determining the best month for discriminating between different vegetation types?

I ordered and downloaded several (Surface Reflectance) Landsat 5-8 images from USGS Earth Explorer with the purpose of choosing a few of them to calculate some Vegetation Indices for each (NDVI, SAVI, ...
0
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1answer
16 views

Tasseled Cap Transformation coefficient and Bias Value

I want to perform Tasseled Cap transformation of Landsat 5,7 and Landsat 8 data manually in arc GIS.please let me know where from I can get the coefficient values and Bias values for the following ...
0
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2answers
53 views

Classification of digital orthophoto

I have digital orthophotographs from 2013 that I'm attempting to classify in an effort to extract all the cultivated/pasture land from. I'm using the "Reclassify by Ascii File" tool for this ...
0
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1answer
45 views

Divide into grid and Mosaic using google earth?

Is it possible to download 1:2000 scale of a town using google earth image? If divide the whole area into grid and mosaic them is an option, how it is done using google earth? I tried using grid. But ...
2
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0answers
22 views

Important to perform atmospheric correction when attempting to identify coral reefs?

I want to identify coral reefs using multi-temporal Landsat data and Lyzenga's Transformation method. In relation to pre-processing the image, should atmospheric correction be done or not? If not, ...
1
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1answer
44 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 ...
1
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0answers
54 views

How to rectify a georeferenced Google Earth image and corresponding layer

I am still a newbie to georeferencing and ArcGIS. I imported an image with place markers from Google Earth. Then I opened up the image in ArcGIS Desktop 10.3.1. I then georeferenced the control ...
2
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2answers
88 views

Raster image thresholding using python

I would appreciate if someone could guide me for applying thresholding technique to input raster image using Python. I intend to extract impervious surfaces from a high resolution raster such as ...
2
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2answers
188 views

image segmentation of RGB image by K means clustering in python

I want to segment RGB images for land cover using k means clustering in such a fashion that the different regions of the image are marked by different colors and if possible boundaries are created ...
2
votes
1answer
32 views

How to remove compression from jpeg2000 NAIP imagery?

I downloaded a 4-band 1m spatial resolution NAIP image from Earth Explorer. The default image format is jpeg2000. You can see the trees in the attached image appear grainy, more so than what you ...
2
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0answers
37 views

Which preprocessing comes first for pansharpened imagery- atmospheric correction or orthorectification?

For pansharpened imagery, what preprocessing method to do first- is it atmospheric correction or orthorectification? From my readings, it seems the former but the rational polynomial coefficients or ...
0
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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 ...
0
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0answers
43 views

Image formats to use for land cover classification in Python? [duplicate]

I am supposed to classify images for different land covers or land uses in Python. I read somewhere that the spectral module of Python is required to do the processing of Hyperspectral image data. ...
1
vote
1answer
35 views

How to convert GOES-R (15) IR image from gray-scale to brightness temprature

How do I convert satellite IR images taken by GOES-R (15) from gray-scale to brightness temperature? We can download the IR satellite images, and read its RGBA values. But how can we convert this RGBA ...
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0answers
20 views

Second order rectification display problems

I'm using GRASS 7.0 to geo-rectify oblique images taken from a fixed altitude and using RTK-GPS data as a GCP (as a vector file) for the process. The survey area is very small and flat, so I'm not ...
1
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1answer
102 views

Removing Shadows from Aerial Imagery in ArcGIS

I am creating an automatic change detection tool in Python for ArcGIS 10.2 using aerial imagery. The tool works but it also detects shadow change. I have been able to create a classified raster of ...
0
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0answers
24 views

What is the most correct way to perform accuracy assessment of the detection of only one type of materials from satellite data?

The error matrix is the most commonly used method for accuracy assessment that provides appropriate accuracy measures to compare different classification techniques. However, this kind of accuracy ...
0
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0answers
139 views

QGIS Raster Calculator giving a NaN output

This is my first time using QGIS and I am trying to use it to generate NDVI maps from data captured by my UAV. However when I apply the NDVI formula in the raster calculator using my NIRGB image the ...
2
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0answers
64 views

Sophisticated generation and calculation of Vector entities from Raster Data?

The first image below is shown a raster wish represents the altitude value. I created this raster by applying this process, bu using this process we can manually select an upper and lower area (so 2 ...
0
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1answer
69 views

How to separate details by color from raster?

How to separate details by color from raster? Is it possible in ArcGIS or any other software? I have tried Spatial Analyst. I want to use RGB .tiff image which is scanned map. It consists of all the ...
0
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0answers
112 views

Error in downloading MODIS image using R script

I am trying to download "MOD13A3" MODIS image using R script (http://r-gis.net/?q=ModisDownload) but each time it's ending in error. How to make it work ? ...
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0answers
50 views

How to fit Google Earth satellite image to UK OS 50 DEM

I have extracted a DEM tile from the UK Ordnance Survey's free OS Terrain 50 dataset The tile contains spot heights for a grid comprising 51 nodes (West to East) by 51 nodes (North to South) with ...
1
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1answer
133 views

IR/R could not detect when using landsat 8 in ERDAS 2014 Is there a alternative way around?

I'm using ERDAS 2014 and I upgraded from ERDAS 2013. I am doing a lot of band indices for various kinds of such as clay, ferrous, Mineral composite and so on.. from landsat 8. Using the indices in ...
2
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2answers
251 views

Accuracy assessment in eCognition

How to do accuracy assessment of classified images in ecognition? I have done the image segmentation for Worldview-2 image. Then, I have processed for classification for class names (e.g ...
1
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1answer
120 views

How to remove band from stack in ERDAS 2013?

I have a Landsat 8 scene where I have stacked 11 bands. I need to remove one band from the stacked layer. Is there a toolbox in ERDAS 2013 that allows me to take out a band? I am aware that ENVI ...
0
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0answers
92 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 ...
1
vote
1answer
37 views

Iterative Mean of Means Infinite Loop for calculating H-t Index

I'm trying to create a function that will calculate an Ht-Index for Quantifying the Fractal or Scaling Structure of Geographic Features (but am new to R) which basically just finds nested means of ...
1
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1answer
63 views

How to create an image of maximum pixel values from an input layer-stack image in ERDAS Imagine?

I have 12 MODIS images (one of each month). I want to create a single image having maximum annual pixel values for each pixel. I did layer stacking operation in Erdas Imagine 13, but how to extract ...
4
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3answers
147 views

Estimating vegetation composition from digital images

I am running a Master's project researching Greater prairie-chicken nest and brood survival. Some of my intended covariates include local vegetation measures using digital imagery. I would like to use ...
0
votes
1answer
48 views

Cut a hole into a geotiff

I have two hillshading geotifs that I created using gdaldem hillshade. One covers a huge area with an OK resolution and the other has a much higher resolution for a smaller part within the huge area. ...
1
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0answers
27 views

PMI and PMW images

i recently archieved .pmi and pmw images which converted from tiff. So now i can not open, please help me to open or convert this filetype to other aerial imagery formats.
1
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0answers
18 views

What are the advanced fusion techniques for fusing 3 band multispectral and 242 band hyperion hyperspectral dataset?

I have used some of the image sharpening techniques such as Wavelet, Gram-schmidt, Principal component, Brovey. Other than this what are the new and advanced fusion techniques and in which software it ...
0
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0answers
65 views

Calling each pixel using spatial modeler language of Erdas Imagine?

How to call each pixel from a 4 layered raster image using while loop of spatial modeler language in Erdas imagine 2011? I need to consider each pixel as a 4*1 matrix and want to calculate the ...
3
votes
2answers
209 views

High resolution satellite

Can any one tell me from where I can buy commercial High resolution Satellite images for Biodiversity research ? I need some websites that sells these kind of images ?
1
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1answer
267 views

How to Read&Write .tiff images in java using GDAL library

I searched many sites to learn about this but I didn't find anything. I need step by step process for reading .tiff monochromatic image in java using Gdal library.
3
votes
1answer
128 views

It is possible to verify landsat reflectance values?

My question is really wide today, as I am still beginner in Remote sensing. I´ve asked a GRASS programmer to prepare for me Landsat reflectance values from raw DN values (1 scene per year from 1987 to ...
1
vote
1answer
266 views

How to create a mosaic in QGIS with cutline and feathering for Landsat-8 imagery

1 - I have two scenes Landsat-8 RGB 6/5/4 and I need to mosaic them: 2- This is my cutline in polygon format that will smooth the overlapping area: 3 - So, I need to create a mosaic with ...
1
vote
1answer
155 views

Which DOS method use to convert at-sensor radiance to at-surface values in GRASS (landsat data, i.landsat.toar modul)?

I am trying to calculate surface reflectance values from raw Landsat DN data downloaded from GLOVIS. I have imported Landsat data in GRASS 6 with header by i.landsat.import and reprojected the scene ...
3
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0answers
56 views

Appropriate resolution of images for image classification?

I am attempting to perform image classification on some maps that I have in PNG format. This classification is failing due to there being too many many pixels in the training samples (I appear to be ...
1
vote
1answer
102 views

ERROR in Resolution Merge using ERDAS IMAGINE 2013

I have attached an example image to show the problem: When i have to Resolution Merge, it will come error this process. How to solve this problem? I would like some suggestions regarding this error.
1
vote
1answer
109 views

Signature File Creating Issues [closed]

I'm working on a school project and running into an unexpected issue while trying to create a signature file. I have four classes in the Training Sample Manager consisting of: Permeable, Impervious, ...
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0answers
10 views

How to avoid background zero values in erdas imagine model maker? [duplicate]

Does anyone know how to avoid background black color/ zero value in background pixels in processed images using erdas imagine? Particularly in model maker. It's confusing in statistical calculation.
2
votes
2answers
432 views

automatically geo- and ortho- rectify raw Landsat data using DEM

I have a dataset of 20 Landsat scenes (MSS, TM, ETM+) for 20 years (one scene per year). Scenes are in WGS 84, EPSG 32634 coordinate system and I can easily project = geometrically correct them to ...
3
votes
2answers
261 views

Extract values from raster based on points and pixels adjacent to the point

I have an issue. I have a set of points (n=~2000) and I would like to extract the pixel values from multiple rasters (a single-raster solution is also ok) for location of that point as well as that of ...
6
votes
3answers
407 views

How to generalize training data for a random forest classifier?

I am working with a random forest classifier in eCognition (new with eCognition 9.0). The image shows 8 NAIP tiles I am attempting to classify using approximately 100 training points. The training ...