You can’t do much better for still image compression than JPEG. Video codecs use the high redundancy of images in time to get better compression when compressing a series of images.
I wanted to archive images from my home security cameras (which save still JPEGs over FTP to a Raspberry Pi) and save some disk space so I whipped up a script to pull them down and transcode them to video.
My primary transportation is an elBodaBoda electric assist cargo bike from Yuba bikes. It’s a great bike and a real car replacement with cargo and passenger capacity. The electric system comes with a tail light but no head light. It does however include an auxiliary power output that supplies 6V whenever the tail light (and control panel back light) is switched on. So I headed down to my local makerspace and quickly whipped up a headlight.
When my Toq smart watch stopped accepting charge, and I was told I wasn’t eligible for a warrantee repair because I received it as a gift (seriously Qualcomm?) I figured I might as well try repairing it, or at least finding out what was inside.
Continue reading User serviceable parts inside: Replacing a smartwatch battery
Espressif’s ESP8266 WiFi SoC is an increasingly popular chip for Internet of Things projects, both hobby and professional, because it combines a capable MCU with a WiFi radio in a single chip for an amazingly low cost. It’s received a lot of attention in many blogs but I wanted to give a little bit more technical depth on the MCU architecture and my best practices for programming it. There are some idiosyncrasies which have to be taken into account when programming to get the most out of the SoC.
I have been published in Circuit Cellar magazine:
I will be presenting at the 2015 Embedded Systems Conference in Silicon Valley on Custom Soft Cores for Digital Sensors on FPGAs which will be an introduction to easily creating custom communication soft cores to reduce resource use and speed programming of FPGA based sensor hubs interfacing with digital sensors.
Designing a smartwatch, making it waterproof is a no brainer. The Qualcomm Toq does an elegant job on the hardware, with only capacitive buttons and inductive charging, there’s no need for any kind of wholes in the body. But I was surprised to discover that the firmware isn’t waterproof. When the watch is immersed or gets many water droplets on it as a pictured above, it interprets each droplet as a touch and the UI goes crazy, paging through menues etc. Crushed under this erroneous touch spam, it crashes and locks up pretty quickly.
Lesson: Always test everything and remember to waterproof your firmware.