View on GitHub

Quorten Blog 1

First blog for all Quorten's blog-like writings

Recording video from Raspberry Pi camera

quorten

2017-01-03

Categories: raspberry-pi  
Tags: raspberry-pi  

Okay, so I got my Raspberry Pi camera, so I have to figure out how to use it. Let’s see.

20170102/DuckDuckGo raspberry pi camera video
20170102/https://www.raspberrypi.org/learning/getting-started-with-picamera/

Oh, interesting, Raspberry Pi Foundation has an official worksheet on creating an infrared bird box camera setup. And yes, it even includes instructions to cut the glue away to get your manual focus camera! So now we know it’s officially endorsed, not just some hacky thing that’s unofficial.

20170102/https://www.raspberrypi.org/learning/infrared-bird-box/

More advanced way to stream video. Yeah, these are the kinds of articles I’d be looking for.

20170102/https://blog.miguelgrinberg.com/post/stream-video-from-the-raspberry-pi-camera-to-web-browsers-even-on-ios-and-android

NTFS filesystem on CentOS

quorten

2017-01-01

Categories: centos  
Tags: centos  

How do you setup NTFS filesystem access on CentOS? CentOS does not have default support for NTFS access. You must install the packages manually, and from a non-default repository at that.

20161231/https://wiki.centos.org/TipsAndTricks/NTFS

Raspberry Pi Zero in my hands, getting started

quorten

2017-01-01

Categories: raspberry-pi  
Tags: raspberry-pi  

Okay, first of all, so I got my new Raspberry Pi Zero, and now I’ve got the USB on-the-go cable, but I can’t get the hub to work! So, first I start searching. Apparently, there is a known problem that the Raspberry Pi Zero does not work well with all USB hubs. For some, it works great. For others, it works with caveats. Still others, it might not work at all.

20161231/http://raspberrypi.stackexchange.com/questions/57606/raspberry-pi-zero-refuses-to-detect-usb-hub-tried-multiple-hubs
20161231/https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=127158
20161231/http://raspberrypi.stackexchange.com/questions/57014/does-a-usb-hub-work-with-raspberry-pi-zero

So anyways, next I get to experimenting. With power, without power, turn on, turn off. After lots of experimentation, here’s what I’ve found works well with my Sabrent USB hub. Well, I shouldn’t say it works well, but it works, with caveats.

First of all, turn on your Raspberry Pi Zero. At this point, your hub should have both buttons on it turned OFF. The power should be plugged in, though. Having the hub plugged into the Raspberry Pi Zero through the USB on-the-go cable is optional.

Read on →

Lossy 3D model data compression and surface fractures

quorten

2017-01-01

Categories: 3d-scanning   3d-scanner  
Tags: 3d-scanning   3d-scanner  

Lossy 3D model data compression and surface fractures. Sure, model splitting allows you a mesh more similar to the real topology, but for a surface that has a lot of fractures, would that not compress as well? Indeed, the “messy” way does compress better, given that there are less mesh points. Then again, lossless compression might help to alleviate this particular problem.

Startup.com documentary and stock market stuff

quorten

2017-01-01

Categories: random  
Tags: random  

Side note: The publisher “Artisan” published the documentary Startup.com.

20161231/https://en.wikipedia.org/wiki/Startup.com
20161231/https://en.wikipedia.org/wiki/Dot-com_company
20161231/https://en.wikipedia.org/wiki/Stock_market_crash

Oh, ticker tape, so that’s where those stock market abbreviations come from.

20161231/https://en.wikipedia.org/wiki/Ticker_tape

Piano keys were used as an input device on early stock tickers.

20161231/https://en.wikipedia.org/wiki/File:Hughes_telegraph.jpg

Behavioral finance, interesting, studies of human ill-logic when it comes to financial decision making.

20161231/https://en.wikipedia.org/wiki/Behavioral_finance
20161231/https://en.wikipedia.org/wiki/Hyperbolic_discounting
20161231/https://en.wikipedia.org/wiki/Dynamic_inconsistency
20161231/https://en.wikipedia.org/wiki/Discounting
20161231/https://en.wikipedia.org/wiki/Holding_the_bag
20161231/https://en.wikipedia.org/wiki/Crowd_psychology

DreamWorks Animation history

quorten

2016-12-30

Categories: media-prog  
Tags: media-prog  

Okay, so now I’m wondering. What about DreamWorks? They have some computer animation system they’re using, but what is it? They’re definitely much more elusive and less publicized than is the case with Pixar, Industrial Light and Magic, Sony Pictures, and Disney. Okay, so let’s turn to Wikipedia. What does Wikipedia have to say?

20161229/https://en.wikipedia.org/wiki/DreamWorks

Oh, remember, DreamWorks Animation, DWA. By the way, the “SKG” does not refer to any software graphics engines, it refers to Steven Spielberg, Jeffrey Katzenberg and David Geffen, or SKG for short. In fact, much of the software used for the computer animations came from Pacific Data Images. They were an early entrant into 3D computer graphics, and they basically developed all of their own software in-house. Their main early business was making animated graphics to decorate TV channels like NBC. Some peculiarities that set Pacific Data Images apart from many of the other companies was that they did NOT lease supercomputers nor did they incur any debt. Their growth came entirely through profit. They instead relied on technology advances in low-cost computers to increase their capacities. Also, Pacific Data Images is one of the longest-lasting computer graphics companies, unlike many of the others, and their entire operation went smooth until their purchase by DreamWorks Animation, after which they were affected by the turmoil of the larger company.

Read on →

Raspberry Pi GPIO info, HATs, camera, UART, lithium-ion battery, USB gadgets mode, schematics, anti-static paper

quorten

2016-12-29

Categories: raspberry-pi  
Tags: raspberry-pi  

Okay, time to figure out how the GPIO pins work on the Raspberry Pi. What voltages do we get? Answer: 3.3 volts from the GPIO pins. In other words, straight out the max voltage of your laser module. Also the typical voltage for CMOS circuits, of course. Also, note that the Raspberry Pi Zero provides 3.3 volt and 5 volt pins. These are digital-only pins, of course. If you need analog and such, you’ll have to use ADC and DAC devices.

20161228/DuckDuckGo raspberry pi gpio voltage
20161228/https://www.raspberrypi.org/documentation/usage/gpio/
20161228/https://www.raspberrypi.org/forums/viewtopic.php?f=28&t=40150&p=329080

Wait, what was the alternative mentioned on Adafruit to soldering a pin header to the Raspberry Pi GPIO pin slots?

Adafruit page for Raspberry Pi Zero v1.3:

20161228/https://www.adafruit.com/products/2885

Oh, it was HATs. Pi HATS & PLATES:

20161228/https://www.adafruit.com/categories/286

Read on →

CNC milling versus 3D printing

quorten

2016-12-28

Categories: raspberry-pi   3d-scanning   3d-scanner   3d-printing  
Tags: raspberry-pi   3d-scanning   3d-scanner   3d-printing  

Again, I reiterate. What is CNC milling? Basically, it is a computer-numeric-controlled machine that cuts away material from an existing block. Subtractive manufacturing, in other words. 3D printing as often referred to is additive manufacturing.

So what makes 3D printing so much more exciting than CNC milling? Well, you don’t have to end up with all this cut-away waste product that you have to dispose of, and you don’t have to start by putting down a block of already existing material. In essence, it is simply much more efficient in practical terms. But also, as to the reason of why it features so much more heavily in the media than CNC milling, well, that’s because the process of seeing this machine build up “something from nothing” is just so much more visually striking and awe-inspiring than seeing a machine cut away from an already existing block of material. Well, duh, anyone can do that. Just not quite as accurately as a machine, but hey, come on! We seen artistic sculptors do just that, and they do a good enough job at it, so yeah, it’s not that much more interesting to watch a machine do it. The machine is a little faster, sure, but overall, not “awe-inspiring.”

Info on USB, PoweredUSB, and Nokia Pop-Port

quorten

2016-12-28

Categories: raspberry-pi  
Tags: raspberry-pi  

Revisiting the Wikipedia USB article. Wow, this is by far one of the most important articles on Wikipedia. It’s also very important that I can read the most up-to-date version of this article to know what’s going on with the latest USB technology in the market. Like the difference between Mini-A, Mini-B, Micro-A, and Micro-B USB connectors.

By the way, the industry decided that Micro USB would be the gold standard for charging all mobile devices. Well, as of 2016. Yeah, in earlier eras, they previously used Mini USB, but now Mini USB is seen as clearly to big and thick to be able to easily fit within modern slim mobile devices.

Oh yeay, another important thing in the USB article was the photographs of the USB power meters. Yeah, that could be useful for assessing whether the power supply of a USB device is working properly.

20161227/https://en.wikipedia.org/wiki/USB 20161227/https://en.wikipedia.org/wiki/USB_decoration 20161227/https://en.wikipedia.org/wiki/PoweredUSB

Wow, PoweredUSB? An early non-standard proprietary extension of the USB standard for transferring larger amounts of power to connected devices, very popular on NCR point-of-sale terminals. It is being largely supplanted by the modern USB charging specifications.

Read on →