All Questions
46 questions
2
votes
0
answers
19
views
Area size generated by editor behind legend elements is missing when exporting PNG with QGIS Layout
I use QGIS Version 3.28.3-Firenze.
In a QGIS Layout, I add the sum of area to each class in the legend via the editor.
I use the following expression:
@symbol_label
|| ' ('
|| round(aggregate(@...
- 109
2
votes
1
answer
299
views
Opening local XYZ Tiles source on QGIS
I am trying to add an XYZ Tiles source of a map that I downloaded in PNG format to QGIS. It has been cached with Global Mapper. It works very well with Global Mapper and SASPlanet, but it appears like ...
- 41
0
votes
1
answer
386
views
Creating a GeoTIFF with PNG & XML [closed]
I want to make a GeoTIFF file to use in a navigation app. What I currently have is a PNG with the map and a XML that goes along with it. Does anyone know how to somehow combine them and export it as a ...
0
votes
0
answers
105
views
Opening .png.aux.xml file in QGIS
I received a .png.aux.xml file. I have tried to read it with the GDAL translator and by making a URL from the code. I haven't been able to open the file in QGIS.
Any ideas?
0
votes
0
answers
87
views
TIFF resolution decreases when opening it in the layout (QGIS)
I have a TIFF which I want to put in to the layout in order to add the legend etc. However, when I open it in the layout the resolution decreases significantly. I tried it with the TIFF as well as ...
- 253
1
vote
1
answer
250
views
QGIS 3.22 : Put some custom PNG icons on a map programmatically,to creare a tracker [closed]
I'm developing a framework using QGIS SDK. It must show some icons updated during time like a tracker. "Some boats on a map with different icons" I have also to perform a selection on an '...
- 31
0
votes
1
answer
578
views
Export PNG in QGIS, same extent but outputs are not exactly the same
I export the PNG with same extent, same resolution and scale
but the output width are not exactly the same.
It's quite annoying to me, and I have no idea why could this happen
Are there any ...
- 1
1
vote
0
answers
922
views
Saving 16bit raster to RGB PNG (or TIF) in QGIS
I was following this post here: Converting Grayscale GeoTIFF to PNG using QGIS results in all black image
I don't want a grayscale but RGB PNG.
When I do Raster->translate and select byte I only ...
- 195
4
votes
1
answer
185
views
Gradients Changed on Export in QGIS when Coord Mode set to Viewport
I made a map in QGIS that includes a couple different gradients. Here you can see an indicator map that has a gradient fill enabled. (This image is from the print layout/composer.)
(Here is the ...
- 415
1
vote
1
answer
378
views
Extracting all polygons from GeoTIFF raster layer as PNG images using QGIS
I have a GeoTIFF file with multiple separated polygons on it as the following:
I'd like to find a way of extracting all these polygons as separated individual PNG images, just so I can have them as ...
- 1,173
0
votes
0
answers
362
views
Is there a way to use QGIS' qgis:tilesxyzdirectory algorithm from a shell script?
I currently have a KML file which I upload to QGIS as a layer. From there I navigate the UI to Raster tools -> 'Generate XYZ tiles (Directory)' under the processing toolbox.
For the EXTENT ...
1
vote
0
answers
2k
views
Converting GeoTIFF to PNG results in completely black image
I have a set of DEM tiles (TIFF format) retrieved from https://cteco.uconn.edu/data/download/flight2016/index.htm which I would like to convert to 16-bit PNG format so that I can use them as ...
- 111
0
votes
0
answers
85
views
Exporting very large map to image in QGIS [duplicate]
I'm trying to use QGIS 3.10.14 to create a hydrological map to edit (as a PNG) in image editing software. My purpose is recreational.
I've paired the Copernicus EU-hydro river network with ESRI ...
- 21
4
votes
2
answers
3k
views
How to convert GeoTiff to PNG + World file in QGIS
I have quite a big area with DTM as a GeoTIFF. I want to save it to PNG with world file, but how to do it just in QGIS?
I know I can export view to PNG with world file, but it looses quality (Project/...
- 81
2
votes
1
answer
838
views
QGIS crashing when exporting very large image
I'm trying to export a PNG of the OS 250k raster with OS Open Rivers over the top. Trying to export the entirety of the national grid caused it to crash, so I tried again with the bottom half of Great ...
- 21
3
votes
1
answer
2k
views
Exporting a raster map to PNG in QGIS keeping the exact legend colors
I'm developing a plugin for QGIS called 'Mappia_Example' to allows the community to publish its maps online. But i need some help, i am trying to export a map in QGIS to PNG but its using aproximated ...
- 93
0
votes
2
answers
2k
views
Digitizing PNG image in QGIS
Following Getting polygons from PNG images for the QGIS Shapefiles
I intended to digitize the following PNG image in QGIS 3.8 following this instruction:
https://www.qgistutorials.com/en/docs/...
- 3,791
2
votes
0
answers
2k
views
Getting polygons from PNG images for the QGIS Shapefiles
I would like to have ready polygons (borders) from some .PNG image and use them in QGIS as a shapefile.
My file looks like this:
which is crude raster PDF.
My goal is to execute all borders (marked ...
- 3,791
3
votes
1
answer
4k
views
Exporting map error from QGIS
Whenever I try to export a map as an PNG image I get the 'successfully export' message but there is no file generated. The error happened in Zanzibar so I changed to Noosa but I still can't export the ...
- 31
5
votes
1
answer
1k
views
Batch export of layers as individual PNG files in QGIS 3.4?
I have hundreds of layers. I'd like to be able export each one as a PNG. I can do this by selecting one, and going to project, export map to image, calculate from layer -> select layer -> save. ...
- 103
1
vote
2
answers
1k
views
Calculate 16-bit elevation values from a 32-bit RGBA image?
Say a single-band 16-bit (UInt) raster with values representing elevation (meters) must be converted to a 32-bit RGBA PNG image (8-bits/band) for use in a web application. The image dimensions must be ...
3
votes
3
answers
4k
views
ERROR 1: Error : band 1 has no color table
I would like to convert a GeoTIFF to PNG or JPEG RGB, and my GeoTIFF is stripped of a lot of valuable data (I think..)
I am on ubuntu and I am using gdal_translate to try and make a GeoTIFF turn into ...
- 145
6
votes
0
answers
2k
views
Convert TIFF raster layer to PNG
I have been given some images in TIFF format, and I need to convert them to the PNG format. I have been given that the TIFF file contains 4 bands: R, G, B, and NIR (which I do not need for the PNG). ...
- 161
0
votes
1
answer
728
views
Calculate elevation from rgb from png created from qgis
I am using qgis to create a raster elevation image (png) from SRTM data. I need to create a png via qgis which I will then query to determine the rgb of particular pixels via php. How do I define a ...
- 1
1
vote
0
answers
51
views
How to workaround truncation of text description for elements in qgis-modeler 2.18.15?
I am trying to make a QGIS processing workflow through the Graphical Modeler (QGIS 2.18.15). I have completed it, and wish to export it as a *.PNG. However, the elements and algorithms I added to the ...
- 412
1
vote
1
answer
1k
views
Png, prj, pgw same name, but png doesn't show up after loading. What SRC to take?
someone gave me a dataset with the three types of files, but when I load as a raster the png.files it doesn't show up on the maps. They ask me what SRC to take and I don't really know which one to ...
3
votes
1
answer
571
views
What CRS to use for cylindrical raster world map?
I've drawn a cylindrical world map for a fictional planet. Exported it as png and scaled it, so one pixel corresponds to one km at the equator and from north to south pole.
I tried several ...
- 95
2
votes
1
answer
332
views
Save to PNG changes colors
I am trying to save this print composer as PNG
When I open the saved file, this is the result
The same thing happens if I save to pdf. Any idea what's going on?
- 1,128
2
votes
2
answers
3k
views
Convert TIF to PNG without normalizing alpha
I'm trying to make some height maps with elevation data from https://earthexplorer.usgs.gov/. Since they give you assets in separate TIF tiles, I need to convert them to PNG and stitch them together ...
- 33
2
votes
1
answer
746
views
QGIS export png with accurate hex color values
I have a 32 bit TIFF raster layer in QGIS with one band of integer values between 49 and 72 with some no data values. I'd like to end up with an 8 bit PNG image with matching pixel values. I don't ...
- 121
1
vote
1
answer
432
views
Wrong dimensons on .png-file when using gdal_translate
I am using
gdal_translate -of PNG -ot UInt16 -scale MIN MAX 0 65535 "source.tiff" "output.png"
in the command-prompt to create a .png-file from a .tif-file that I created using the Interpolation-...
- 127
4
votes
1
answer
6k
views
How can I create a 16bit PNG heightmap in QGIS?
I am new to QGIS or any GIS software. I have been using a totalstation to measure a hillside and I am trying to convert the point cloud to a 16bit png heightmap that I can use in Unreal Engine 4.
I ...
- 127
2
votes
2
answers
3k
views
Georeferencer QGIS not working?
I am trying to georeference a .png file. After inserting all the data I get the following error
"Transform Failed: Failed to compute GCP transform: Transform is not solvable."
What can be ...
- 483
8
votes
1
answer
16k
views
Import PNG symbols in QGIS
I would like to upload some symbols into QGIS using version 2.14 (Essen). I would like to upload a PNG but it seems the only format available is XML.
Do you know if its possible to upload PNG's ...
- 475
10
votes
1
answer
1k
views
How to fill composer map with canvas data and export composition as png using Python script in QGIS
I'd like to create a Python script in QGIS that will take some data (shp + tif, in my example), use tamplate Map Composer (from a file) and export created composition to a png image.
With almost no ...
- 101
3
votes
1
answer
1k
views
QGIS Map Composer goes blank, outputs corrupt PDF
I am using 64bit 2.10.1-Pisa on Windows 10.
When I set up my composer to print, everything looks fine until I try to print or export. The composer goes completely blank and outputs a corrupted PDF ...
1
vote
0
answers
529
views
QGIS Atlas generation - Export atlas as images - only JPEG, want PNG
I can't find an option to choose image format while exporting Atlas, choices are Export atlas as images / as SVG / as PDF
The dialog that opens has no options and it always exports as not so good ...
- 11
0
votes
2
answers
530
views
Transparent png tiles showing up weirdly in QGIS?
I have Ubuntu 14.04 running QGIS 2.6. I'm loading a raster layer, but the transparent PNG shows up poorly. The black lines along roads aren't showing up and the anti-aliasing looks off. I'm thinking ...
- 399
8
votes
2
answers
8k
views
Exporting GIS Images with Transparency
I'm trying to export some images of Gulf of Mexico infrastructure that will later be used for non-GIS purposes as overlays onto sea current/weather maps (likely in photoshop).
I have no clue how to ...
- 133
0
votes
1
answer
403
views
Georeferencing PNG against Google maps with OpenLayers plugin
I am trying to georeference blueprints to the footprint of a building. I'm using the Google Satellite image from the OpenLayers plugin to do this. The blueprints are rotated about 30 degrees. When I ...
- 495
2
votes
0
answers
703
views
QGis, how to overlay and correctly position and scale a KML and image onto a Google base map
Being totally new to the entire GIS subject I managed to install and get runnning QGis (2.2.0 on Mac) properly, get my Google Maps showing (I set the the CRS to WPSG:3857) and I also got my KML file ...
- 123
2
votes
1
answer
6k
views
How can I correct a .pgw file for a PNG image?
I have a PNG file and I need its .pgw file to be set with NAD 83 as the projection. I have created a .pgw file:
799
0
0
-799
-122.562
37.1946
However when I open the PNG in QGIS or ArcMap 10.2 it ...
- 1,447
2
votes
2
answers
2k
views
Creating VRT from PNG files in QGIS
This is similar to a question asked by someone else, re OS tiles. However, there is a difference!
I have a large number (over 10k) of georeferenced png files which I have mosaicked in ArcMap, but ...
- 29
8
votes
2
answers
3k
views
How do I use QGIS python console to iterate through simple layer queries and png outputs?
I'm really new to QGIS coding and I'm having a hard time finding (especially) the api classes/functions to carry out actions of the Query Builder window.
I'm basically trying to do this:
Iterate ...
- 171
2
votes
1
answer
1k
views
How to create a worldfile by bounding box?
I need to create a worldfile from Bigmap Application. I've successfully to grab a pack of PNG tiles and the pearl app mosaicking all in one. The BigMap site shows the raster bounding box and util ...
- 545
26
votes
5
answers
12k
views
Obtaining print quality PDF or PNG output from QGIS?
I work with people who use ArcGIS Desktop and they have found the best resolution output images are made by creating PDFs. They tell me that *.png and the rest out of ArcGIS Desktop are not ...
- 1,782