[Qgis-user] [EXTERNAL] Re: 2019 USGS 7.5min topo sheets

[Fielding, Eric J (US 329A)]

I was able to open a USGS GeoPDF for a 2018 map of Pasadena, Calif. with Adobe Acrobat (and Acrobat Reader) and it loaded quickly. The file is a vector file with all the line work stored as vectors. I was also able to open it in Adobe Illustrator, but that was slower. Illustrator sees the GeoPDF with only one layer, but has a huge number of vector lines for all the contours. I don’t see a raster layer in Illustrator. QGIS 3.10.3 on my Mac was not able to open the GeoPDF as either a Raster or Vector database.

I also noticed that opening the folder with the GeoPDF in Adobe Bridge caused the Bridge program to allocate 19 GB of memory, which is not very helpful on a laptop with 16 GB of RAM. I had to quit Bridge to get the memory back. This is probably similar to what people noticed with keeping the GeoPDF on the Windows Desktop.

From the “Font not available” warnings in Illustrator, I see the GeoPDF must be created with an ESRI program as some of the fonts had ESRI in the name. I assume that ESRI ArcGIS can open the GeoPDF.

++Eric

From: "qgis-user at stripfamily.net" <qgis-user at stripfamily.net>
Date: Tuesday, April 21, 2020 at 12:45 PM
To: Mike Flannigan <mikeflan at att.net>, "qgis-user at lists.osgeo.org" <qgis-user at lists.osgeo.org>
Cc: "Fielding, Eric J (US 329A)" <eric.j.fielding at jpl.nasa.gov>
Subject: [EXTERNAL] Re: [Qgis-user] 2019 USGS 7.5min topo sheets

I am running Qgis 3.4.2 on Windows and I can load the new style geopdf USGS 7.5' quads, including the imagery layer.
It's slow and grinds qgis to a halt while it loads, but it does work. The different layers, which are independently controllable in Acrobat Reader are flattened when the topo is opened in Qgis, which rasterizes the image and presents it as one raster, not separate layers.
USGS has made these maps much less useful by adding the aerial imagery layer, at least for me. Qgis isn't the only application that flattens the layers, and the imagery obscures way to much for my taste.

On 4/21/2020 12:22 PM, Mike Flannigan wrote:

Much to my surprise I think you are correct.
QGIS can open a TIF file (and a zipped TIF file),
but I can't get a GeoPDF to open in QGIS.  If I
convert the GeoPDF to a TIF with GDAL, it still
will not open and gives error "Missing Codec".

Very surprising.  I know from past experience that
Global Mapper v6.04 will view TIF files that have
been converted from GeoPDF via GDAL.


Mike


On 4/20/20 5:00 PM, qgis-user-request at lists.osgeo.org<mailto:qgis-user-request at lists.osgeo.org> wrote:

It sounds like you downloaded a new USGS product format called the GeoPDF. The ".pdf" suffix is the big clue. I don't know if QGIS 3.2.3 can read those files. I would try downloading the map in a different format. I don't know what site you are using, but the USGS TopoView site (https://ngmdb.usgs.gov/topoview/) has the maps available as JPEG, KMZ, GeoTIFF, and GeoPDF. I would recommend the GeoTIFF format as all versions of QGIS support that.

Best,
    ++Eric Fielding

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