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How to read image files from a Camera (Nikon D5600) with Python

Forgive me if I've left anything out or goofed up formatting conventions; this is my first time posting on this sort of forum.
So I've got a Nikon D5600 that I'm using as part of an (extremely basic) image analysis setup. I'd like to be able to use images from it without having to manually transfer the files over each time I run a test, but I've had some trouble getting access to the files.
To be clear, I don't want to capture screenshots of a video; I understand that this is possible, but the resolution is about 1/3 smaller in video, which is a bit of an issue for my application.
So, when I was 6 hours more naive, I plugged in the camera via USB to my (Windows 10) desktop, tried calling the image using the exact (well, I did change the slashes out) file path windows gave me in the properties screen:
img = cv2.imread("This PC/D5600/Removable storage/DCIM/314D5600/CFW_0031.jpg")
That didn't work.
I checked that the command I was using wasn't the issue by copying the picture to another drive:
img = cv2.imread("D:/CFW_0031.jpg")
That worked.
So I think, and think is a bold claim here, that it's something to do with the "This PC" bit of the path. I've read some old (circa 2009) posts about MTP and such things, but I'm honestly not sure if that's even what this camera uses, or how to get started with that if it is in fact the correct protocol.
I've also tried using pygrabber (I believe it's a wrapper of direct show, though my terminology may be wrong) to control the camera via python, but that also didn't work, although I did manage to control my webcam, which was interesting.
Finally, I attempted to set the assign a letter drive to the camera, but found that the camera wasn't in the manager's list of discs. It's entirely possible I just did this method wrong, but I don't quite see how.
Edit regarding comment from Cristoph
-I just need to be able to use the image files in python, probably with opencv. I suppose that counts as reading them?
-I've attached a screenshot of what the "This PC" location looks like in the file explorer. The camera shows up under devices and drives, but doesn't have a drive letter.

Creating a PPTX template using python

I have a requirement involving making a large pptx file with loads of charts, images and tables dynamic. This pptx has default styles. Is there any library or method to make a template so that I can insert the dynamic parts. Like docxtpl library allows us to input a dict and generate a docx file.
Thanks.

You can try the following python modules:
https://pypi.org/project/template-pptx-jinja/
https://pypi.org/project/pptx-template-simple/
https://pypi.org/project/python-pptx-templater/
With the first one, the example they show, it works fine, but im having trouble applying it in another custom ppt.. keep getting "Unepexpected end of template".
The third one didint work for me though, maybe you have more luck.. and now i will try the second one.

I'm not sure I understand your problem...
python-pptx (a tag you've used) is the fundamental programmable way to build a presentation - whether from a "template presentation or not.)
I hope nobody will mind me advertising my md2pptx open source project for taking Markdown and images and making a presentation.
However, I think md2pptx doesn't help you unless you have a way of turning graphs into eg PNG files - and I suspect that's not what you want.

Any good pdf417 Barcode libraries for Python?

I'm looking for a good python module to generate pdf417 barcodes. Has anyone used one they liked?
Ideally I would like one with as few dependencies as possible, and one that runs on both linux and MacOSX.

We recently had to approach this problem as well, and being a Python shop we wanted a Python solution. It become clear the elaphe is the project that had the potential to actually accomplish pdf 417 barcode.
However what we found was it errors by todays standards, and so we entered the hunt to fix the library. Turns out elaphe must generate an outdated form of *.eps post script that can't be interpreted by ghost script and this is where the bar code generation fails.
Well fortunately elphae uses a common library behind the scenes called Barcode Writer in Pure PostScript # http://bwipp.terryburton.co.uk
This common backend library which has many projects in multi-languages using it to generate projects. The fix specifically for us was to fork elaphe, and correct it's *.eps file generation.
To determine what is broken in the *.eps, look at this other site that is made using postscriptbarcode, and it let's you generate the pdf417 barcode online (as well as other formats): http://www.terryburton.co.uk/barcodewriter/generator/
Once you generate a pdf417 barcode it gives you the option to download the .png, .jpg, and YES the .eps file!
Using this .eps file you can pipe it to ghost script and tweak the parameterization to get the exact pdf417 barcode you are looking for. Then take this result and integrate it into the elaphe library and actually get a pull request on that thing ....
Seems to be a bit of work, but nothing that can't be knocked out in an afternoon. It is ideal to get the elaphe library back in shape to generate these without making this enhancement.
Please note that the performance of this approach for us is a few seconds to generate this barcode due to the fact it creates the 2000 line eps file and pipes it to ghost script which generates another image file that we send back as the final barcode result. This is not as performance as code128 with reportlab.
Perhaps room for optimizations: Is pillow faster than PIL in anyway? Do we need all the parts of the eps file to generate the barcode of type pdf417? Other ways to optimize?
Anyway, great question Ken and I hope you find this to be a great answer.

I guess the issue in elaphe reported by Matteius in 2013 has been fixed, since the issues and commit logs show updates on the pdf417 topic since then.
Anyway, there are now a few other options (got the list with either pip search elaphe or pip search pdf417) :
elaphe ;
elaphe3 (fork of elaphe tested against python3) ;
candybar (no documentation ? also a webservice) ;
pdf417gen ;
treepoem (about the name : barcode -> bark ode -> tree poem =D ) — edit : didn't dig the issue, but as of today generation of PDF417 seems broken.
All but pdf417gen support several types of barcodes.
Note that the documentation of bwipp (on which are based elaphe and treepoem) only mentions 5 levels of error correction (1 to 5), while pdf417gen claims to support 9 security levels (0 to 8).

Reportlab does have an extension called rlbarcode, but this one does not include support for pdf417 codes. I do not know of any other extension for reportlab including support for pdf417 bar codes.
Anyway, if you are interested in generation of pdf417 codes from python, you may be interested in this project: elaphe.
I have still not tested it (in fact, I need to generate pdf417 from python, and I found this thread as well as the elaphe project page) I am going to download the elaphe tools in order to test it right now.

Dealing with huge (potentially over 30000x30000) images in Python?

I'm trying to use a python script called deepzoom.py to convert large overhead renders (often over 1GP) to the Deep Zoom image format (ie, google maps-esque tile format), but unfortunately it's powered by PIL, which usually ends up crashing due to memory limitations. The creator has said he's delving into VIPS, but even nip2 (the GUI frontend for VIPS) fails to open the image. In another question by someone else (though on the same topic), someone suggested OpenImageIO, which looks like it has the ability, and has Python wrappers, but there aren't any proper binaries provided, and trying to compile it on Windows is a nightmare.
Are there any alternative libraries for Python I can use? I've tried PythonMagickWand (wrapper for ImageMagick) and PythonMagick (wrapper for GraphicsMagick), but both of those also run into memory problems.

I had a very similar problem and I ended up solving it by using netpbm, which works fine on windows. Netpbm had no problem with converting huge .png files and then slicing, cropping, re-combining (using pamcrop, pamdice, and pamundice) and converting back to .png without using much memory at all. I just included the necessary netpbm binaries and dlls with my application and called them from python.

It sounds like you're trying to use georeferenced imagery or something similar, for which a GIS solution sounds more appropriate. I'd use GDAL -- it's an excellent library and comes with easy-to-use Python bindings via Swig.
On Windows, the easiest way to install it is via Frank Warmerdam's FWTools package.

I'm able to use pyvips to read images with size (50000, 50000, 3):
img = pyvips.Image.new_from_file('xxx.jpg')
arr = np.ndarray(buffer=img.write_to_memory(),
dtype=np.uint8,
shape=[img.height, img.width, img.bands])

Is a partial load useful? If you use PIL and the image format is .BMP: you can open() an image file (which doesn't load it), then do a crop(), and then load - which will only actually load the part of the image which you've selected by crop. Will probably also work with TGA, maybe even for JPG and less efficiently for PNG and other formats.

libvips comes with a very fast DeepZoom creator that can work with images of any size. Try:
$ vips dzsave huge.tif mydz
Will write the tiles to mydz_files and also write a mydz.dzi info file for you. It's typically 10x faster than deepzoom.py and has no size limit.
See this chapter in the manual for an introduction to dzsave.
You can do the same thing from Python using pyvips like this:
import pyvips
my_image = pyvips.Image.new_from_file("huge.tif", access="sequential")
my_image.dzsave("mydz")
The access="sequential" tells pyvips it can stream the image rather than having to read the whole thing into memory.

Generate image for each font on a linux system using Python

I'm looking for a way to list all fonts installed on a linux/Debian system, and then generate images of some strings using these fonts. I'm looking for your advice as I kind of see how to do each part, but not to do both:
To list all fonts on a UNIX system, xlsfonts can do the trick:
import os
list_of_fonts=os.popen("xslfonts").readlines()
To render a string into an image using a font, I could use PIL (Python Imaging Library) and the ImageFont class.
However, ImagesFont.load expects a file name, whereas xlsfonts gives a kind of normalized font name, and the correspondence between the two doesn't seems obvious (I tried to search my system for files named as the output of xlsfonts, without results).
Does anyone has an idea on how I can do that? Thanks!

You can do this using pango, through the pygtk package. Pango can list fonts and render them.

you best bet is to do a find on all the fonts on the system, and then use ImagesFont.load() on the results of that list. I don't know where the fonts are on Debian, but they should be in a well known folder you can just do an os.walk and then feed the filenames in that way.