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Video Conferencing (LCA)

I’ve just done a tech check for my LCA lecture. I had initially planned to do what I had done before and use my phone for recording audio and video and my PC for other stuff. The problem is that I wanted to get an external microphone going and plugging in a USB microphone turned […]

AS400

The IBM i operating system on the AS/400 is a system that runs on PPC for “midrange” systems. I did a bit of reading about it after seeing an AS/400 on ebay for $300, if I had a lot more spare time and energy I might have put in a bid for that if it […]

Your Device Has Been Improved

I’ve just started a Samsung tablet downloading a 770MB update, the description says:

Overall stability of your device has been improved The security of your device has been improved

Technically I have no doubt that both those claims are true and accurate. But according to common understanding of the English language I think […]

USB Microphones

The Situation

I bought myself some USB microphones over ebay, I couldn’t see any with USB type A connectors (the original USB connectors) and bought ones with USB-C connectors. I thought it would be good to have microphones that could work with recent mobile phones and with PCs, because surely it wouldn’t be difficult to […]

USB Cables and Cameras

This page has summaries of some USB limits [1]. USB 2.0 has the longest cable segment limit of 5M (1.x, 3.x, and USB-C are all shorter), so USB 2.0 is what you want for long runs. The USB limit for daisy chained devices is 7 (including host and device), so that means a maximum of […]

Censoring Images

A client asked me to develop a system for “censoring” images from an automatic camera. The situation is that we have a camera taking regular photos from a fixed location which includes part of someone else’s property. So my client made a JPEG with some black rectangles in the sections that need to be covered. […]

Video Decoding

I’ve had a saga of getting 4K monitors to work well. My latest issue has been video playing, the dreaded mplayer error about the system being too slow. My previous post about 4K was about using DisplayPort to get more than 30Hz scan rate at 4K [1]. I now have a nice 60Hz scan rate […]

Comparing Compression

I just did a quick test of different compression options in Debian. The source file is a 1.1G MySQL dump file. The time is user CPU time on a i7-930 running under KVM, the compression programs may have different levels of optimisation for other CPU families.

Facebook people designed the zstd compression system (here’s a […]

A Good Time to Upgrade PCs

PC hardware just keeps getting cheaper and faster. Now that so many people have been working from home the deficiencies of home PCs are becoming apparent. I’ll give Australian prices and URLs in this post, but I think that similar prices will be available everywhere that people read my blog.

From MSY (parts list PDF […]

IT Asset Management

In my last full-time position I managed the asset tracking database for my employer. It was one of those things that “someone” needed to do, and it seemed that only way that “someone” wouldn’t equate to “no-one” was for me to do it – which was ok. We used Snipe IT [1] to track the […]