Example code to Estimate heading or course of travel or bearing given two GPS locations taken from a recorded path. A lot of GPS devices will report heading along with latitude and longitude, but what if you lust have a series of GPS locations recorded from a path, how can you estimate heading or course […]
More easily receive UDP Data via boost::asio providing just IP address and port umber. The boost::asio classes provide a cross platform way to communicate via UDP without having to use the raw socket libraries, however they can be confusing and hard to use do to their designed-in flexibility. Sometimes I just want to provide an […]
If you’re working with UTC times, you may be upset to find that mktime() always converts using your local time zone thus wrecking your UTC times. Instead of mktime() use: Linux/Posix: timegm() Windows: _mkgmtime() For example, let’s use timegm() to make a UTC time which we will pass to SolarAzEl() to calculate the Solar Elevation […]
C++ code to estimate Solar Azimuth and Elevation given GPS position and time. For reasons that I won’t go into here I found it necessary to estimate Solar Azimuth and Elevation given GPS position and time. Now there is quite a bit of information on how to this on the old inter-web, none of it […]
Programming with time is difficult and error prone, for this reason I usually try to keep things in UTC so that I don’t have to worry about time zones and daylight saving offsets etc. When in C++ I mostly use the boost::ptime library but I was surprised recently about tricky it seemed to be to […]
Q: How can I speed up encoding & decoding of JPEG images on my embedded system?
How can I use libjpeg to encode directly to memory without using a file on my embedded system?
How can I get the Subversion (SVN) URL for a single file using Tortoise SVN?
So I had a problem, as part of an embedded software system I was working on I needed to periodically send some GPS information via UDP datagrams to other devices on the network – really simple stuff, transmit a string to an IP address on a given port, Fire And Forget, send a string from […]
Recently I was struggling to achieve very accurately synchronised camera and light triggers for a real-time computer vision project that I was working on, my original PIC embedded system for triggering everything using a PIC micro-controller had a fairly reliable accuracy of about 250us which was sufficient for a few years, but for various reasons […]