Changing into the timecoverspider directory, you’ll see the following Scrapy project structure: |- scrapy.cfg To create our Scrapy project, just execute the following command: $ scrapy startproject timecoverspiderĪfter running the command you’ll see a timecoverspider in your current working directory. If you’ve used the Django web framework before, then you should feel right at home with Scrapy - at least in terms of project structure and the Model-View-Template pattern although, in this case it’s more of a Model-Spider pattern. Again, I’m no Scrapy expert so I would suggest consulting the docs or posting on the Scrapy community if you run into problems. If you get an import error (or any other error) it’s likely that Scrapy was not linked against a particular dependency correctly. You can test that Scrapy is installed correctly by opening up a shell (accessing the scrapy virtual environment if necessary) and trying to import the scrapy library: $ python ![]() Scrapy should take a few minutes to pull down its dependencies, compile, and and install. In either case, now we need to install Scrapy along with Pillow, which is a requirement if you plan on scraping actual binary files (such as images): $ pip install pillow Again, this is optional, but if you’re a virtualenv user, there’s no harm in doing it: $ mkvirtualenv scrapy I then used virtualenv and virtualenvwrapper to create a Python virtual environment called scrapy to keep my system site-packages independent and sequestered from the new Python environment I was about to setup. Note: This next step is optional, but I highly suggest you do it. $ sudo apt-get install libxml2-dev libxslt1-dev The first thing you’ll need to do is install a few dependencies to help Scrapy parse documents (again, keep in mind that I ran these commands on my Ubuntu system): $ sudo apt-get install libffi-dev ![]() I actually had a bit of a problem installing Scrapy on my OSX machine - no matter what I did, I simply could not get the dependencies installed properly (flashback to trying to install OpenCV for the first time as an undergrad in college).Īfter a few hours of tinkering around without success, I simply gave up and switched over to my Ubuntu system where I used Python 2.7. Looking for the source code to this post? Jump Right To The Downloads Section Installing Scrapy We’ll then use this dataset of magazine cover images in the next few blog posts as we apply a series of image analysis and computer vision algorithms to better explore and understand the dataset. Specifically, we’ll be scraping ALL magazine cover images. In the remainder of this blog post, I’ll show you how to use the Scrapy framework and the Python programming language to scrape images from webpages. While scraping a website for images isn’t exactly a computer vision technique, it’s still a good skill to have in your tool belt. Well, if you’re lucky, you might be utilizing an existing image dataset like CALTECH-256, ImageNet, or MNIST.īut in the cases where you can’t find a dataset that suits your needs (or when you want to create your own custom dataset), you might be left with the task of scraping and gathering your images. Whether you’re leveraging machine learning to train an image classifier, building an image search engine to find relevant images in a collection of photos, or simply developing your own hobby computer vision application - it all starts with the images themselves. ![]() The reason is because image acquisition is one of the most under-talked about subjects in the computer vision field! Since this is a computer vision and OpenCV blog, you might be wondering: “Hey Adrian, why in the world are you talking about scraping images?” Click here to download the source code to this post
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