Questions tagged [noise]
May refer to ambient sound or random/uncorrelated patterns of samples in data, particularly raster data.
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How to find the standard deviation in GPS measurement of latitude and longitude?
Let's say my GPS configuration is said to have a precision of 10 meters. I have taken this as the standard deviation in the GPS measurements. But the measurements that come from GPS are latitude, ...
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Smoothing a DEM with visible grid
I have a DEM (1x1m) whose hillshade shows like this:
As you can see, a grid shows up and that could be a problem for hydrological modeling.
Do you know why this happens?
How can I remove this grid ...
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How to remove noise from a DSM (city center) to create a 3D printable model
For the company I work for, I need to create a 3D printable model of a part of a city's downtown area.
At my disposal (upon request to local government authorities) I have point clouds from LiDAR ...
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IDW interpolation with noise values in ModelBuilder in ArcMap [closed]
I'm using ModelBuilder to create a noise map using IDW. But in the attribute table I have two columns with different values: Lden is the average of the values throughout the day and Ln is the night ...
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Raster data summarized in different vector polygons
I am using ArcGIS Pro 2.9.2 and I have a raster dataset of noise pollution across England with different noise levels. I also have the LSOA vector shp file. I want to get the average noise level per ...
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Determine average noise in a shapefile using QGIS
I am completely new to QGIS.
I am currently undertaking an analysis on urban green spaces (UGSs) in the city of Luxembourg.
I have noise data (expressed in Lden (dB)) on car, rail and air traffic ...
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Removing noise and detecting groups of rastercells that forms possible features in ArcMap
This is a raster image containing cells with values ranging from 0 to 10. You can see rastercells forming lines, which illustrates agricultural ditches, and more groups of red cells within the fields, ...
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Receiver points appear as circle around building footprints in Openoise plugin for QGIS
I have been trying to get receiver points using Openoise plugin for QGIS 3.18 Zurich but they appear in a circle form around the actual building footprints.This is a Noise Modelling tool that helps to ...
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Is it possible to host QGIS on a computing server?
I'm working on a project with QGIS Desktop 3.18.3. My plugin always crashes.
Is it possible to host QGIS on a computing server? If so, will it improve the performance?
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LiDAR XYZ Data Cleaning
I have tons of LiDAR Bathymetric XYZ data of 5m resolution.
Data has a lot of noise/spikes which takes ages to clean for a small area. I have tried using Fledermaus for 3D cleaning the data. Is there ...
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QGIS: exporting contours to DXF with height values
I am using this video tutorial to create ground contours for a noise model in iNoise.
https://www.youtube.com/watch?v=JxCxBREEqG0
See tutorial 8 https://dgmrsoftware.com/products/inoise/gallery/
When ...
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Spike and crater detection in DSM using machine learning / deep learning / computer vision techniques
I'd like to try machine learning / computer vision / deep learning approaches for detecting artifacts in Digital Surface Models, and am specifically interested in doing this for common artifacts like ...
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LiDAR data denoising algorithm complexity
I want to remove outliers (noise) from LiDAR data.
Currently I'm using the same algorithm as LAStools:
The LAStools software version 171215 implements a straightforward outlier
removal ...
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Proper formula for computing signal-to-noise ratio of a camera?
I have a 5-band muultispectral camera, and I'm trying to find the signal-to-noise ratio (SNR) to supplement some research data I collected. Cameras with low SNRs generally have lower-quality images ...
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Removing noise selectively from DEM using QGIS?
I am looking for a processing tool that can remove noise selectively from a DEM (Mostly SRTM). My current workflow includes "Fill sinks" and "r.neighbours". The problem is that the tool is blind to ...
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Speckle on LiDAR data
Does LiDAR data suffer from the speckle noise like the SAR images and ultrasound cardiac images I'm used to?
I think speckle noise is inherent to all active sensors, but I'm not sure for LiDAR ...
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Fixing spikes in DSM from LiDAR?
I have a DSM derived from drone LiDAR that I want to use as a base to drape imagery and, paired with a DTM, as a basis for estimating canopy height/volume.
Unfortunately, the DSM has has many "spikes"...
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Editing LiDAR point cloud to remove noise/outliers present below and above ground?
I have "dirty" LiDAR data containing first and last returns and also inevitably errors under and over the surface level. (screenshot)
I have SAGA, QGIS, ESRI and FME at hand, but no real method. What ...
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Slope raster seems to come out distorted?
I've been trying to get a slope raster from a DEM, so I can reclassify it and aggregate it with land use data.
The problem is that my slope raster seems to have a lot of distortion (diagonal lines). ...
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Cleaning up polygon generated from NDVI raster
So I have NDVI raster files for about 1000 acres of vineyards we manage. What I have done is created a model that takes the NDVi raster, reclassifies it to isolate out the areas of high vigor, then ...
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Gap filling for linear features using ArcGIS Desktop?
I have a Landsat time series from which I derived NBR using bands 4 and 7, and delta NBR (to show changes). I then set a threshold based on the mean and standard deviation delta NBR values to ...
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How to create a sound map using ArcGIS?
I have locations of the points which produce sound. I want to create a sound map based of those points, topography, and the distance at which a sound can travel. On this picture you can see the red ...
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Eliminate noise when using spatial join with tolerance
I have two networks, which doesn't align perfectly with each other, so when I want to attach attributes from one to another, I have to use spatial join with a certain amount of tolerance. However, at ...
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Detecting and fixing outliers in a GPS trajectory
I need to find an algorithm or method that can detect outlier latitude longitude points in a trajectory during post-processing, which can then be fixed (brought back into the trajectory's path based ...
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A method for noise reduction in GPS derived cycling routes
I'm pre-processing GPS data to assess possible methods for a planned research. The aim of the research is to use crowd-sourced cycling routes data to plan a cycling paths in an Israeli city.
...
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Managing or Reducing noise in a mosaic raster
I have created a raster with the Mosaic to New Raster tool from 3 separate rasters. However in my mosaic I have some consecutive pixels which seem to be the noise of the previous procedure. Is there ...
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Is it right to remove salt & pepper effect from a product produced by clean images?
I have two images from classification (different years) and I want to find the changes of land cover . I have cleaned the two images (salt and pepper). When I create a cross product of the category ...
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Computing population exposure
I am new to ArcMap.
I have polygon layer, which represents buildings, and each polygon has number of inhabitants in Attribute table. Then, i have a layer which shows noise levels in the area, ...
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Using raster to clip vector data
I have high res raster data covering 2million km sq, with a field where each cell has a value from 0 to 100. I need to create a "mask" using the cells with a value over 12 in that field. I then need ...
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How to find a route given a set of noisy points
First of all, I'm a total noob to GIS problems.
Let's say I have a set of noisy GPS points (tracked while driving) along a number of streets. Is there a way to get the most likely route that generated ...
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Which interpolation method for noise mapping?
I want to create a noise map with measured point data. But I want to have a planar representation, so I need an interpolation method.
Which one is the 'best' for measured noise data?
I prefer 'IDW'...
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Fixing Landsat 7 SLC-off in ENVI
I have a couple of Landsat 7 images and they all have striping as a result of the SLC failure. Does anyone have any suggestions as to how to destripe the image using ENVI? I plan to use these images ...
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How to perform Noise Pollution Mapping using ArcGIS for Desktop?
I've been trying to do a noise pollution map, and I really don't know where to start with the information I have. The end result needs to be like in the link below.
I've seen the question, Creating ...
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Masking/removing polygons from shapefile
I have a shapefile containing the road traffic noise of a city.
The shapefile has 5 columns, where 'noise_in' (noise interval) ranging from 1-5 is included.
I want to remove/mask the road noise from ...
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Creating noise maps using ArcGIS for Desktop or Open Source Desktop GIS? [closed]
In a previous role I helped create Noise Maps for Northern England.
The predicted noise levels was done using the IMMI package (which I can recommend) and the cartographic output was done in ArcMap. ...
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Why is the imported TIFF file distorted with noise in Quantum-GIS?
I've a TIFF-file. Loading the raster image into QGIS does not display correctly. (Using the Add raster layer button.) It seems to be distorted with noise. See image below:
The source of the TIFF file ...
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Disabling sounds/beeps in QGIS
Is there any way to disable, mute, or otherwise change the incessant message 'beep' in QGIS?
I need volume on the PC for other unrelated notifications.
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280
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Terrain Beautification
The satellite imagery i am rendering is not realistic does not look good.
So i was planning to improve things through code(like adding noise to data or using different overlay texture for different ...
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Adding noise to a raster
I want to add some fine-grained noise to a raster in an automated python process (i.e. I do not want to use Photoshop or GIMP). I looked at PIL, but unless I'm mistaken, it doesn't seem to have any ...
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