Extracting Raster Values using Points, Polygons & Lines | QGIS

In this tutorial, you will learn how to extract raster values using points, polygons and lines with the aid of QGIS. QGIS can be used to inspect raster data, especially with the aid of 'Identify Features' where you would be able to obtain the pixel value by manually clocking over the raster pixel. However, if you had to perform this task for a massive point dataset, it can be rather challenging to perform this task manually. However using the Sample Raster Values tool of QGIS, you would be able to load in a points shapefile, and extract the raster pixel values that spatially intersects the locations of the points just in one go.

If you are interested in obtaining spatial statistics/ zonal statistics, you would be able use the Zonal Statistics tool to obtain information such as average, sum, min, max of the pixel values that are bounded by a user define polygon. Furthermore, if you want to extract raster values along a line to create a 2D profile graph, you would be able to do that using the Profiles from Lines (SAGA GIS) tool.

Here's the timeline:

00:00 - Introduction
02:05 - Extracting Raster Values using Points
06:45 - Extracting Raster Values using Polygons
12:08 - Extracting Raster Values using Lines

#raster #qgis #zonalstatistics

[muhammadzeeshan]

Sir there is no other channel on YouTube that explains Arc GIS in such an amazing manner like GEO DELTA LAB .Sir kindly keep it up I'll be very thankful to you

[niampahamidou]

It's really nice! Thanks a lot for that.

[buttingheads]

Good info. What would be the next step to identify the actual min and max points in the raster for each polygon?

[hussainal-lawati]

Thank you for the great tutorial. Really helpful.

Is there a way to do batch zonal statisics from polygons?
I have a set of around 100 multispectral images, each with 5 bands (layers).
I want to find zonal statisics for each band in each image.

[akkalukmoppijit]

thank you very much for the video so I have a question in case of the profile of line, if we want the create a distance between point is 200 m, how we can create the profile. Thank you

[sukristiyanti-]

How to extract values from those three polygons, like what points and polylines do? thanks a lot...

[hmkbywn]

Thank a lot for this video. And I want to know that can we get the mean value of the DN number of pixels as this

[yuhaozhao]

Thank you so much for your great illustration! I have a question what to do if polygons (shape file) and rasters (many tif files) have different coordinate reference systems? Should I adjust the tif files' coordinate reference or the polygons' coordinate reference?

[kilaladashina]

Thanks alot!
😅 I had like 15000 points,
entering the data manually was a load

[sazzaduleanan]

Could you please make a video on how to clip a netCDF file using shape file? This would be of great help.

[klauslgeiger]

Is there a way for QGIS to list all the raster values that fall within the boundary of a polygon? In other words, is there a tool in QGIS like Zonal Statistics that can "list" raster values within a defined area instead of performing a mathematical operation?

[ntsakovictor]

Hi, how do you change the interval distance in QGIS profiles from lines., or does it randomly seoect the distance from one point to another its self.

[himanshukhanve]

I have already a points and I wants to extract raster data of that point then what I do...

[muhammadzeeshan]

Kindly make some more videos on Arc GIS

[ambicasharma]

Hi Geodelta labs, When I installed SAGA, it did not work. Is there any way we can do it without using SAGA?

[SubhashchandMahich]

how to elevation in meter and millimeters my means prefix

[ibiswas]

Sir, please make a video on ArcGisPro

[mohannadal-hajyaseen]

try to buffering line and then use zonal

[pmostarac]

Sample raster values (point)
Zonal statistics (polygon)
Profiles from lines (line)

[NJCM]

In QGIS 3.28, Zonal statistics is not avalaible anymore 🥲