If you have been doing OpenCV or Python machine learning, you have most likely come across PyImageSearch. If you come across a sale for this service I would recommend trying it out if you are learning some machine learning. This past week they have run a free promo 7 day trial, which gave me an opportunity to browse these.Continue reading “PyImageSearch Review”
If like many you have been starting gardens and planting rather than traveling and visiting in recent months, there is one important thing to consider lately – severe weather reports including frost on your crops. I noted there was a little red (!) alert icon on an Android weather widget, but there seems to be no such alert for desktop computer or Linux computer or phone. It is a fairly simple to make this alert though with a simple script:Continue reading “Severe weather alerts with a simple Python script”
Newer Ubuntu releases do not even pre install Python2, and after an upgrade and installing latest Python3.x included in the release, you likely have some old ones there too. Since you most likely will not be using the python2 unless you use some very old library, you can clean them up, clear a lot of disk space and use the “python3” / “pip3” command instead.Continue reading “Cleaning up Python – and old libraries”
As you may have noticed, the repeater-START app doesn’t currently have an option to change that internal km/mile calculation. It also does not have any option to filter the repeaters of VHF, UHF or your preferred band.
Let’s see how to add a new dialog, then store the options, and load them on your program’s start:Continue reading “Building a Linux app part 8: Adding an options screen”
How often has it happened to you… you build a simple script to calculate something, run some bulk process, and coming back after an hour or so it just hangs with no output. Is it doing something or stuck? You could debug it, using WinPdb or Visual Studio Code debugger or GDB to run it step by step, but that would lose the time that it has been processing. Instead, you can use Pyrasite, a program for looking in to a running Python script!Continue reading “Injecting commands and debugging a running Python program, with Project Euler example”
If you’ve read through how Support Vector Machines work, you probably know the linear simple SVM might not work in all cases… but how does it fail? Let’s take a look at an example I tried like to my simple example… but change it to be a larger space than just 4, and separated with a region in the middle, and the region around it (positive, negative labelled areas to learn):Continue reading “Machine learning SVM – the usefulness of kernels”
Human pose estimation is something useful for robotics/programming as you can see what position a person is in a picture. For last weekend’s Hackrithmitic I did an experiment for fun using computer vision pose estimation. To start with I found several possibilities with available libraries:
- Tensorflow js has been used to say, don’t touch your face, but it takes a massive amount of cpu.
- Openpose is a popular one, only licensed for noncommercial research use, and there is a Opencv example for it that doesn’t quite show how to use it.
- AlphaPose is supposedly faster and has a more clear license and possibility for commercial use – if you want that as a possibility. I checked out the install instructions and worked but for “python3” instead of “python”. It also misses obvious step of installing cuda for your Nvidia system before running.
- GluonCV is another, which seems more user friendly. This one I was able to get running in a few minutes with their example:
After you’ve upgraded your Ubuntu machine a few times, you might find that free disk space is low and some Python commands have issues. Programs like Bleachbit can help you clear old packages or cache that you don’t need, but sometimes you need a minor manual fix as documented here. As you may know, Pip is the main package management you’ll use to install packages you use, so this can be problematic.
After upgrading 16.04 to 18.04, I got an error on command line “pip”:Continue reading “Fixing Ubuntu Python-Pip”
If you are often in a cafe or library with shared internet, it’s best to go through a VPN so any unencrypted traffic isn’t detected by any local hackers – while there are many vpn packages, it is easy enough to make your own and connect to it with shadowsocks. This can give you good performance even on a $5/mo digitalocean server!*Continue reading “Easy VPN with DigitalOcean and ShadowSocks”