Questions tagged [png]

Use this tag when asking questions related to, Portable Network Graphics (PNG), a bitmapped image format that employs lossless data compression

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2
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1answer
241 views

Georeferencing of PNG and Convert to TIFF using Python

I have a PNG image which I am trying to georeference using four corners of coordinate information of the defined input image. When I am trying to convert PNG to TIFF, I am getting 3 bands (R,G,B) ...
0
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1answer
41 views

Export a map and a legend as a PNG with OpenLayers 6

I would like to export a map with a legend in the same PNG using OpenLayers 6. I searched in the OpenLayers documentation but I got just how to export a map (without a legend). How can I do this?
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1answer
35 views

Shader is not working correctly / set(material.[]) is buggy

Concider this first Example: My CGA File: const dryWallCol = "Walltexture1/Drywall4.png" Lot --> primitiveCube(20,20,20) ...
-1
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1answer
77 views

Convert shapefile to PNG using GeoTools

I need to know how to export a .shp file to .png in Java using geotools. I found an example here: Convert geojson to png. But I need convert shapefile to PNG.
3
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1answer
119 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 ...
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0answers
167 views

How to convert GeoJSON to PNG image

I'm looking to use the geojson module in Python, as well as Pilllow to convert a .geojson to a .png image. I know how to extract the data from the file but I don't know what to do from there.
1
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0answers
57 views

Export to PNG produces wrong color background (but not for JPG)

I need to export a map as a PNG image, but when I do the background, which is supposed to be white, comes out gray. This also happens when I export it as a TIFF or EMF, but not as a JPG. I have tried ...
1
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1answer
69 views

Export Raster tiles in JPEG/PNG format using PostGIS

I imported my image with three bands (RGB) with 100*100 tiles using raster2pgsql into the DB. Now, I need to export those tiles separately. I used the following code but it produces a table select ...
2
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1answer
141 views

gdal_translate problem translating 16bit PNGs

I am trying to use the SRTM earth images to convert them into heightmaps for 3D application. I can output a 8-bit PNG like this: gdal_translate -ot Byte -scale -of PNG srtm_44_05.tif heightmap.png ...
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0answers
34 views

Superimposing high resolution but partial coverage images on a smaller resolution images for use in GeoServer

For the same area, I have 2 sets of images, the first is high resolution but it doesn't cover fully the area and the images have somehow uneven borders just like this picture. The second one has ...
0
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2answers
260 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/...
2
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0answers
451 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 ...
1
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3answers
104 views

ExportToPNG produces shifted images

I am using ExportToPNG (in ArcGIS 10.3.1) to produce images from a MXD with WMS data. If I use the interface command ExportMap with the option "1-BIT_MONOCHROME_THRESHOLD" and a threshold at ...
2
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1answer
502 views

Merge *.png files into one using GDAL

I built a Python script that downloads tiles from some map service. This service cannot be imported to QGIS as a tile layer so I decided to download tiles directly using requests module. The script ...
1
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1answer
41 views

Weird looking color when creating tiles from large GeoTIFF

I encounter some weird problem when creating tiles from GeoTIFF. Context: I am generating small tiles from a large GeoTIFF image. The B and R band were swapped so I had to do a gdal_translate to swap ...
1
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2answers
1k views

How to convert PNG files to GeoTIFF using Python

I have a big set of PNG files and EPSG:3006 coordinates of the edges of each file. (actually the coordinates of the edges are given in the file name, like this: 'image_666751_7023263_667007_7023519....
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0answers
443 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 ...
1
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1answer
376 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. Is ...
1
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0answers
64 views

CentOS 7, Mapnik, and Tilestache: Seems like image assets are ignored by Mapnik's point/pattern symbolizers

[Update 6.6.2019] Ok...new detail. I checked a different Apache error log and discovered that it's littered with these errors, generically corresponding to.. failed to allocate png_ptr Actual ...
2
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1answer
27 views

Giving Projection for more than one .png format at same time using ArcGIS Desktop?

I want to give a projection for multiple PNG files at the same time i.e. not one by one. Is there a tool for this or can we give a projection to that folder?
0
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1answer
384 views

Use PNG external graphic for vector layer with OpenLayers 5.3

I am currently working on a webmapping project using Mviewer device, linked to OpenLayers 5.3. I am trying to create a new vector layer to locate points, with js. So far, I managed to create a layer ...
0
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0answers
32 views

From EE GeoTiff to MS Word PNG/JPG?

I would like to put some images from Earth Engine (EE) in my report. So far I screenshot it and paste PNG on MS Word. I see EE can export images to Google Drive. But its geotiff, I can't just paste ...
1
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1answer
108 views

Add PNG as a layer in Mapnik

I'm playing around with Mapnik and trying to add a PNG image over a map created from an XML file. This is my XML file: <Map background-color="white" minimum-version="0.7.2" srs="+init=epsg:3395"&...
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1answer
1k views

Change Leaflet Marker Icon(.png) color programatically [closed]

I have a list of markers. I am assigning an icon to each marker and creating that icon from a black .png circle. I want to change color of that marker based on input value from user. I have searched ...
1
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2answers
453 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 ...
-1
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2answers
434 views

Exporting image from GEE to Google Cloud Bucket in PNG/JPEG format? [closed]

The below lines of code shows the export of the image to the cloud. I am unable to convert my file to JPEG/PNG. I want my image to be saved in PNG/JPEG in the cloud. Export.image.toCloudStorage({ ...
3
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3answers
1k 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 ...
1
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1answer
96 views

Saving content of map.div as PNG using widget with ArcGIS Web AppBuilder?

I basically need to take a screen capture of the div WITHOUT all of widgets and panels on top of it. My plan is to export map scenes for eventual use in PowerPoint, so I want a 'what you see is what ...
0
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1answer
46 views

ArcGIS file export

Am having issues exporting a Layout Map of an area from ArcGIS to any raster format (JPEG, TIFF and PNG). The map gets partially exported with no errors reported. Exporting to PDF works fine. My ...
4
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0answers
759 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). ...
1
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1answer
193 views

Alpha-channel PNG from gdaldem

I was hoping that the following command would give me an alpha-channel PNG which was transparent where the DEM has "nodata": gdaldem color-relief -alpha -of png dem.tif palette.dat out.png I get an ...
0
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1answer
542 views

Filling polygon with png pattern in OpenLayers?

I want to fill a set of polygons with png pattern. Here is an extract of my code : var canvas = document.createElement('canvas'); var context = canvas.getContext('2d'); var pattern; var imageObj ...
2
votes
0answers
33 views

When exporting, mask behind text becomes garbled (Data Driven Pages)

I am using Data Driven Pages with different rotations for a project. When I export to PDF or PNG, the mask behind the text moves and rotates. It does not seem to rotate in the direction of the data ...
2
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0answers
851 views

Export PostGIS geom polygon to PNG

I am trying to build a REST API using Flask and Postgis. I have a PostGIS table with a GEOM column. Querying the table using ST_AsGeoJSON gives me a MULTIPOLYGON with lat, lon in WGS84. [('...
0
votes
1answer
496 views

convert png with alpha channel to GeoTiff

How do I convert a png with an alpha channel to a GeoTIFF using gdal_translate so that the alpha channel gets reflected in the GeoTiff. Currently the GTiff that is produced is resulting in 3 Bands, ...
3
votes
1answer
2k views

Performing gdal translate to png/jpeg?

I tried gdal translate to png: gdal_translate image.bsq image.jpg -of JPEG -outsize 10% 10% -scale and jpeg: gdal_translate image.bsq image.png -of PNG -outsize 10% 10% -scale jpeg looks better ...
0
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1answer
356 views

gdal translate -co, which options are available to PNG?

I can create a PNG with: gdal_translate -of PNG -outsize 10% 10% image.bsq image.png I see there is a -co (creation options) parameter I can pass to gdal translate. Where can I find which options ...
1
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0answers
231 views

Export raster to 8bit png with transparency

I have various scanned images in different file formats (jpg, tiff, png) and I need to georeference, clip and export those images. As a result I need to have a 8 bit png file with transparacy (the ...
0
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0answers
46 views

Pulling Data off PNG map scan using ArcGIS Desktop?

I have scanned a map with several trade routes on it and georeferenced it on top of a hydrology (river system) map of the U.S. The scanned map is a PNG file. How can I pull off the trade routes? ...
1
vote
1answer
743 views

Geoserver SLD style PointSymbolizer ExternalGraphic issue

Any idea why this isn't working? It's taken straight from here: http://geoserver.readthedocs.io/en/latest/_downloads/point_pointasgraphic.sld refernced from this page http://geoserver.readthedocs.io/...
0
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1answer
276 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 ...
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0answers
41 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 ...
1
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1answer
504 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 ...
1
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1answer
167 views

Map Automation Script For Looping Help

Working on a Python script that I will run inside of ArcGIS 10.5 that will export PNG maps. Each map will be a different state and for every state there will be 5 different physician specialty types, ...
5
votes
2answers
2k views

Converting 4-band TIF to PNG while keeping all 4 bands?

I have a number of aerial photos containing both RGB and a near-infrared band. The images are in TIF-format, however I need to convert them to PNG without losing any of the bands. I have tried ...
1
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0answers
357 views

Different image quality for different zoom levels (OpenLayers/GeoServer)?

Original data that raster layers are made of are of a high quality. At a small scale (1:100) this is useful. However at a large scale (1:10 000) it results in ~300KB PNG images which are actually not ...
3
votes
1answer
317 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 ...
2
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1answer
204 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?
2
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1answer
101 views

Why does it take longer and longer to export my maps as png in a loop?

And how can I improve my performance? I wrote a simple python script to export a few hundred maps: Open a MXD, add a layer, apply a definition query, apply a symbology, export to PNG. The definition ...
0
votes
1answer
527 views

Mapnik to reuse colors from geotiff when rendering png format

I am trying to make mapnik read this geotiff file and render it as a PNG file. Unfortunately all the colors from the geotiff file are not retained. The resulting PNG is completely blank. This is my ...