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Questions tagged [digital-image-processing]

The field of raster image processing

2
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0answers
22 views

QGIS raster files not aligned due to different extent

I have a DEM file of building heights calculated from DSM-DTM in QGIS. Based on this DEM file, I generated a mask that indicates the presence of buildings in matlab. However, when I load the building ...
1
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0answers
15 views

What does cumulative count cut actually do?

I have a grayscale satellite image (16-bit image) which is dull (low brightness). When I apply cumulative count cut from 2 to 98 percent (Properties -> Min-Max Setting -> Cumulative count cut), it ...
1
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0answers
514 views

What causes this rainbow image artifact in Google Maps satellite imagery?

I discovered this "rainbow" over the Yellowstone River in Google Maps: View the site in Google Maps: https://goo.gl/maps/y6xETmY859M2 You can see a distinct red, yellow, and blue streak hovering ...
2
votes
1answer
32 views

Reading large image using GDAL?

I want too read large image. The image size is 92117 x 30313 pixels. So far I know cv2.imread can not read large size. How can I read using GDAL API?
0
votes
2answers
71 views

Relative Radiometric Normalization of multisensor Landsat Level 2 images using R

For my time series analysis, i need to use images of the three Landsat sensors (TM, ETM+ and OLI). I chose the already atmospheric corrected surface reflectance/Level-2 products. Due to the ...
1
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0answers
31 views

Assessing quality (accuracy and precision) of digital surface model (DSM)?

I have been trying to build digital surface model from stereo satellite images. I do some initial research of it, it looks like I have to go outside and manually measure the height of an object (...
9
votes
1answer
1k views

Ditch Extraction using LIDAR DTM (1m resolution)

I'm trying to extract ditches using the LIDAR DTM using the software eCognition but I am actually having a hard time since the paper where I based my workflow entitled "Ditches’ network extraction and ...
0
votes
1answer
14 views

Image Overlay 3D Adapt in Google Earth

When adding an image overlay (specifically a GeoTiff exported from QGIS), the image looks great until you turn on 3D buildings or terrain. These features pop through the image overlay, and disrupt the ...
3
votes
3answers
877 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 ...
0
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0answers
10 views

Use of RGB images for plant health classification

GRVI is the greenness index of vegetation, which is certainly not the replacement of the NDVI. However, can anyone justify the use of GRVI from RGB images, for the classification of vegetation using ...
0
votes
0answers
22 views

Mapping a LinearFit to colors

Refering to EE>Examples>LinearFit (https://code.earthengine.google.com/598af3369de7a4845f0325030a66e0e1) I would like to check my understanding. On line 20 comment says: // Display trend in red/blue,...
5
votes
1answer
595 views

Verifying landsat reflectance values? [closed]

I am still beginner in Remote Sensing. I have asked a GRASS programmer to prepare for me Landsat reflectance values from raw DN values (1 scene per year from 1987 to 2013). I have proposed him (...
11
votes
2answers
770 views

Is it scientifically correct to pansharpen landsat reflectance product with pan band

I need to know if it is scientifically valid to fuse/pan-sharpen Landsat 8 surface reflectance products with pan band of that respective band? Landsat reflectance product details can be found at here. ...
1
vote
1answer
148 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 ...
0
votes
0answers
9 views

Normalizing a single band of landsat 8 imagery w.r.t an adjacent one

We have 23 landsat 8 level 2 imageries which has to be mosaiced. Based on date, we have mosaiced individual bands (B1, B2, B3, B4, B5, B6) and now it's down to 5 imageries. But we are not getting a ...
2
votes
4answers
5k views

exporting metadata from gps camera to spreadsheet

I have a question involving exporting metadata from a GPS camera to an application such as a spreadsheet. In essence, I'm working with a significant number of images taken with a GPS digital camera. ...
2
votes
2answers
81 views

Feature normalization (scaling) for Hyperspectral images

I have been straggling with the concept of feature normalization for the hyperspectral images. Respect to my problem I have attached a picture of my problem which clearly stands the issue which I have....
0
votes
0answers
28 views

Matrix union in ArcGIS

How can I do matrix processing in ArcGIS or ERDAS Imagine? l have two different raster images for change detection. Matrix join same code filed information. In this video link already done matrix in ...
1
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0answers
52 views

Earth Engine: Function to generate daily image collection from 3 hourly

I am working with GLDAS-2.1 image collection. I would like to generate a daily image collection with max temperature, min temperature, mean temperature and sum temperature for each day from 3 hourly ...
0
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0answers
14 views

No Data Holes in Certain Tiling Scheme Levels in Mosaic Dataset Imagery Cache

I have a mosaic dataset containing three other mosaic datasets (one containing county imagery, one containing regional imagery, and one containing city imagery) I have them ordered by putting the ...
0
votes
0answers
96 views

Writing code to add calculated image to display in Google Earth Engine?

I wrote a code for Land Surface Temperature (LST) from Landsat 8 images in google earth engine. I have successfully calculated the following steps, NDVI, fractional vegetation (fv), emissivity (EM), ...
0
votes
1answer
595 views

Reading a 4 band image with rasterio (python)

I am trying to view a tif satellite image which has 4 bands. I want to remove the last band (NIR) and view the RGB image only, so I am trying to split the NIR from the rest of the image. Here is my ...
1
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0answers
68 views

Batch processing DTM with Hillshade in QGIS 3

I'm using the Hillshade tool from GDAL library [Raster analysis] in QGIS 3.4. I can't use the batch process with creative options like compress=LZW or profile=Geotif. It doesn't work. The tool works ...
1
vote
2answers
369 views

Pansharpen landsat mosaic in Google Earth Engine

Does anyone have a good way to pansharpen an entire mosaic of landsat 8 images? I would use the Panchromatic band (band 8). I have found tutorials on how to pansharpen a single image, but not for a ...
1
vote
0answers
40 views

Pre-Processing for multi-sensor Time series analyses based on Landsat Level 2 imagery

I downloaded TM, ETM+ and OLI Surface Reflectance Higher-Level Data Products (atmospheric corrected) based on L1TP Landsat images (radiometrically calibrated, orthorectified). I need to include images ...
3
votes
1answer
2k views

supervised classification

I am having a problem in creating new signatures in Signature Editor in ERDAS 2014. Whenever I click on the icon (i.e., after selecting the aoi), it shows an error which says "unable to open ...
3
votes
1answer
86 views

Performing Supervised Classification on Sentinel Image using ArcGIS Desktop?

Is it possible to perform supervised classification on Sentinel Satellite Image with the minimum error. I compared two raster, one being the manual classification of an area using Photoshop CS6 and ...
-1
votes
2answers
455 views

SCP QGIS sentinel 2 authorization error

I am using Qgis 2.18.16, when i tried to download sentinel 2 via SCP interface, I am getting following error: Authentication Required
4
votes
7answers
8k views

Failed to create signature file

I've no clue how to solve this issue in the exercise that I'm trying to perform. The point where I'm stuck is 4. "Create signature file as LandsatCompS.sgs". I've done what it says in the exercise. I ...
0
votes
1answer
27 views

Two different CRS somehow works? [duplicate]

I am overlaying some WGS84 (EPSG:4326) coordinates over a few DEM rasters with EPSG:102710 (NAD_1983_STATEPLANE_NEW_HAMPSHIRE_FIPS_2800_FEET) When they are these two different layer CRS the ...
0
votes
1answer
129 views

How to convert masks generated by rasterio to channel last mask

The problem is about using rasterio to generate mask from GeoJSON file which contains geographic coordinates. The function that I used is from: from rasterio.tools.mask import mask with rasterio....
1
vote
1answer
436 views

How to save an image stretch/enhancement in ENVI?

I am using ENVI 5.3.1 and viewing a georeferenced satellite image with a linear 1% histogram stretch applied to the entire image. When exporting the image with the current histogram stretch using File-...
12
votes
2answers
315 views

Ice type differentiation using satellite data

I would like to classify glacial area by categories of snow (if there is) and ice, but what's most important: between old ice and fresh ice. They have different properties that are possible to ...
7
votes
1answer
448 views

Counting rocks of different sizes on shoreline using ArcGIS Desktop? [closed]

I have a 5cm resolution geotiff image for a shoreline. I need to count the number of rocks in three classes (e.g., >6 feet, 3-6 feet, and <3 feet). I don't have any point cloud data. What will be ...
0
votes
1answer
39 views

Colorize radar imagery so it looks like optical imagery

Here is an imagery from a radar satellite Is it possible to colorize a radar image, so it looks like and enables the same kinds of analysis as for an image captured from an optical satellite (simple ...
3
votes
1answer
506 views

Retrieving exif tags from GeoTiff with GDAL?

I work on toolkit that automatically classifies data from a bunch of aerial cameras. Each camera uses geotagging to store position and time metadata in EXIF tags. When I use GDAL (I use version 2.0....
2
votes
0answers
2k views

Interpreting NDVI value on water?

There is a surreal thing on my NDVI images. NDVI values on lake is ranging from -0.04 to 0.7. (The lake surrounded by forest and has freshwater). Theoretically, negative value of NDVI is correspond to ...
1
vote
1answer
207 views

conditional statements for raster in R - land surface temperature

Im trying to calculate Land surface temperature estimating with Landsat 8 images, but i got stuck in one place and i cant move on. I m following split window algorithm. I calculated NDVI and I have ...
0
votes
1answer
85 views

Satellite image in ArcGIS darker than usual

This is one image from 2013 in some área. This is another image from 2014 in the same área, but darker. why? How can I display it like in 2013. Both are Landsat 8 images.
3
votes
2answers
2k views

Raster image thresholding using python

Can someone 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 roads, sideways and ...
0
votes
1answer
89 views

I can apply tasseled Cap transformation in surface reflectance (not ToA)?

I can not understand if I should adjust the Tasseled Cap index with the surface reflectance values or the Top of Atmosphere
3
votes
0answers
66 views

Processing drone Images of body of water?

I took some pictures of a body of a body of water using a multi-spectral sensor attached to drone. When trying to process the image using Pix4D, more than 50% of pictures were unable to calibrated. ...
0
votes
0answers
165 views

How to compare 2 NDVI images using python?

I want to compare NDVI of 2 images(TIF) of the same area of interest using python. My end result is to get the region on the image where NDVI is decreased(to depict crop damage). Problem: Images have ...
1
vote
0answers
19 views

ArcGIS imagery analysis difference raster errors

I have two DEM rasters from the USGS NED dataset. One is from 2013 and one is from 2017, the extents should, and appear to, be 100% identical. I ran the difference function on the ArcGIS Imagery ...
3
votes
1answer
194 views

ArcMap Image Analysis Window - functionality is grayed out

In ArcMap's Image Analysis Window, none of the tools are available even though I have a raster selected in the window. I do not have Editor turned on. I can't identify why the Processing tools are ...
0
votes
1answer
126 views

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

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 ...
2
votes
1answer
71 views

Aerial picture - how can I extract water drainages on a crop (to vectorize them)

I have a RGB aerial picture of an agricultural crop. The drainages (hundreds of them) can be barely seen because they a very slightly greener then the surrounding crop area (picture is from April). ...
1
vote
1answer
131 views

Atmospheric correction of Landsat 7 slc-off images

I am interested in finding the change in land cover particularly forests. I am working with slc-off images (no other sensor images available for my study). I have done the gap-filling in Erdas Imagine ...
1
vote
1answer
463 views

eCognition TTA Mask : Aerial images in ecognition for supervised classification

I am using eCognition Developer Trial 8.0. I have rgb Drone Otho foto. We want to classify this image for various biotope types exist in that region. We have already an existing classification as a ...
2
votes
1answer
95 views

Is image registration necessary among temporal Landsat images?

I am working on a project comparing each pixel every 4 years for the same AOI from Landsat Images (1986-2017). It involves with Landsat 5, 7 and 8 images. Do I need to perform image registration as ...