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Posted by Justin A. Parr on April 28, 2013
Posted in: Main Page.

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1/2/2020:  Welcome to the new decade!  Maybe we’ll finally get flying cars?

Here are a few updates from yours truly, and Casa de Parr:

  • The Gate controller has been working great!  There were some overheating issues during the hottest part of summer.  On my “to do” list is to figure out some cooling without sacrificing the water-resistance of the IP-67 case.  Maybe an external heat sink?  We’ll see.
  • The pool thermometer has been offline for a couple of weeks now.  I suspect it simply got unplugged, but I haven’t had time to mess with it.
  • Things have been crazy-busy since we moved in May, but are now starting to settle down.  I’m hoping for some quiet time (ha ha) this year to work on various projects.
  • We had another successful turkey this year for Thanksgiving… along with plenty of leftovers.

COVID-19 – Tips for Working from Home

Posted by Justin A. Parr on March 25, 2020
Posted in: Other Stuff. Leave a Comment

In response to the COVID-19 threat, many companies are implementing a work-from-home policy for office workers.

Although working from home can keep you safe from a global pandemic, it can also be more challenging than it sounds.

Here are some tips and tricks for workers and employers, to help you maximize your time, and keep a remote workforce efficient.

Read on…

Continue Reading

COVID-19 – No Bread? Make Tortillas

Posted by Justin A. Parr on March 23, 2020
Posted in: The Light Side. Leave a Comment

Stores are out of bread (and tortillas).

Tortillas are easy to make, and they last about a week if stored in an air-tight zip-top bag.

  • Combine 2 cups of flour, a pinch of salt, 3/4 cup of water, and about 3 tablespoons of fat (butter, lard, vegetable oil, olive oil)
  • Mix
  • Roll in to 1″ balls, and then flatten each ball in to a small disc
  • Use a floured tortilla press or a rolling pin on a floured surface to roll out each ball to 10″.
  • In a lightly-greased skillet on medium heat, cook each one on both sides for about 1 minute per side.

Makes 8-10 tortillas.

Here are things you can do with tortillas:

  • Quesadillas
    • Sprinkle some meat and other toppings on half of a tortilla
    • Sprinkle some cheese on it.
    • Fold in half
    • Grill or fry for 2-3 minutes per side, until the cheese melts and the tortilla is golden-brown on both sides
  • Fajitas / Street tacos
    • Cut your meat in to strips.
    • Grill or fry over high heat with onions and peppers
    • Steam some tortillas to warm them, or use a microwave tortilla warmer
    • Serve family-style with cheese, sour cream, pico, and other toppings
  • Nachos
    • Tear tortillas in to strips
    • Bake until crispy
    • Cover with chili, cheese and other toppings
    • Bake until cheese melts
  • Roll / wrap – makes an excellent substitute for a sandwich.  Lay out a tortilla, then stack on lunch meat, cheese, and other sandwich toppings, and simply roll it up.
  • Thin-crust pizza
    • Stack 2 tortillas, with some cheese sprinkled between them
    • on the top tortilla, spread some pizza sauce, spaghetti sauce, or whatever you have laying around
    • Sprinkle some cheese
    • Add toppings
    • Sprinkle some more cheese (do it, or you’re a communist)
    • Bake for 10 minutes until the bottom tortilla is crispy and the cheese is melted
  • Enchiladas.  I’m not quite sure how that works, but my wife does.  I’m sure you can google for a recipe.
  • Burritos
    • Lay out a tortilla
    • Fill with beans, rice, meat, cheese and other toppings
    • Fold carefully
    • Enjoy
  • Chimichanga
    • Take that burrito, and deep fry it

COVID-19 – Cheap Bidet

Posted by Justin A. Parr on March 22, 2020
Posted in: The Light Side. Leave a Comment

Not sure who all needs this, but here it is:

In the event that you run out of toilet paper…

Go to your local hardware store, and buy one of these:

This is a 1 gallon “garden lawn sprayer” that you can buy online for about $12, or it should be in your local big-box hardware store for about $16.

Note the angled wand…

After you buy a new one (DO NOT use the one from your garage), wash it out thoroughly.

When you go to the bathroom:

  1. Fill with warm water from the sink
  2. Close the lid, air-tight
  3. Pressurize by pumping the handle a few times
  4. Instant, portable bidet

This is cheaper than modifying your plumbing, and warmer than buying a bidet kit that connects to your toilet’s water supply.

Reduce PDF Size of a Scanned Document

Posted by Justin A. Parr on March 21, 2020
Posted in: Tech Support, Tech Tip. Leave a Comment

Reduce PDF Size of a Scanned Document

I recently had to e-mail a multi-page document – e-mail is that awesome 1990’s technology for submitting documents when the recipient doesn’t have a secure file transfer server – only to find that the attachment size was too large.

I scanned in three separate multi-page documents and then used pdfSAM to combine them all in to a single, 9-page PDF document.

Are you with me so far?

The final file size was over 80 meg!

I didn’t think anything of it, until my e-mail server complained about the attachment size.

After a little bit of thinking…

  • I had used xsane, a GUI front-end for SANE.
  • Where Windows has TWAIN, Linux has SANE. 

    Connecting a scanner to a PC pre-TWAIN used to be a kludge, and TWAIN was the answer: a manufacturer-independent hardware interface and driver standard that provides a scanner user interface, and also allows third-party programs to access any TWAIN-compliant scanner via a standard Application Programming Interface (API).

    SANE works like TWAIN, but separated in to two pieces:  front-end and back-end.  The back-end drivers allow the OS to talk to the scanner hardware, and provides generic access to other applications (like the TWAIN API).  This allows any of several SANE front-end user interfaces to access any SANE back-end, even across a network.  Very cool stuff, and there is even a SANE shim for Windows that provides TWAIN services, while using SANE on the back-end.
  • As my print server is a Raspberry Pi (Linux) and my main PC is Linux, it made the most sense to set the Pi up as a SANE back-end server.
  • I scanned all three multi-page documents using xsane, as mentioned, which allows you to scan a multi-page document and then save it as a single file.
  • While poking around a bit, I noticed that the intermediate format for xsane’s multipage applet is TIFF.
  • Like most other computing standards from the 1980’s, TIFF just isn’t very good, especially compared to modern file formats that use much better compression algorithms. 

    Unfortunately, TIFF was developed as a standard file format for scanners, which means that any time you’re dealing with scanners (or, oh lord, fax machines), be prepared to deal with TIFF, despite the fact that it’s a completely obsolete standard.  I mean, while we’re at it, let’s just fire up the 1200 baud modem and a copy of Telix, and we can XMODEM some TIFF files, shall we??

So it became clear that xsane / sane was just saving a bunch of TIFF files, and then copying them straight in to the PDF.

It turns out that Linux has a built-in command to split a PDF apart:

pdftoppm file.pdf imagefilename -png

This will create an image file for each page of the PDF, stored in PNG format.  For example, if file.pdf is 5 pages, you will get:

imagefile-1.png
imagefile-2.png
...
imagefile-5.png

These can then be recombined using ImageMagick’s convert:

convert imagefile-*.png newfile.pdf

As predicted, the resulting file was around 20 meg – 25% of the original file size.

Internally, PDF probably stores the images as TIFF, but in either case, the round trip through the PNG format is what affected the compression.

PNG performs “filtering” or normalization of the image before it’s compressed, and thus, the resulting image is “more compressible”, and the artifact of this process is that going back to TIFF (or any other format) makes the older compression algorithms perform more efficiently with the normalized image data, resulting in a much smaller file size.

Moral of the story:

If you have a huge PDF (or any kind of source image), try converting to PNG and then back again, which might make the original compression more efficient.

Other options:

  • Subsample the document down to a lower resolution.  I scanned at 300 DPI, but my next option if that didn’t work was going to be to subsample the document down to 150 DPI, which would result in a 4x file size reduction.
  • Go from color to grayscale or black-and-white.  Going grayscale from color usually results in about a 4x reduction in file size, and black and white from color might result in readability issues, but can save 16x or greater from the file size.

Frankenbolt (verb)

Posted by Justin A. Parr on March 6, 2020
Posted in: Good Design - Bad Design, Justinisms. Leave a Comment

Frankenbolt (verb):

To assemble two or more completely dissimilar and poorly integrated components in to one unit, as in the patchwork manner of Frankenstein’s Monster.

Examples

  • “Reporting was an afterthought.  The developers obviously licensed a third-party component and simply Frankenbolted it in place at the last minute.”
  • “Every application should stick to its core mission.  Without a core mission, scope creep always results in an application with modules Frankenbolted all over it, like some bizarre freak-show attraction.”

 

That One Time I Expensed a Gun Case

Posted by Justin A. Parr on February 15, 2020
Posted in: The Light Side. Leave a Comment

That One Time I Expensed a Gun Case

 

Setting the Scene…

Back in the early-2000’s, WiFi was far from ubiquitous.

  • Most laptops and other mobile devices didn’t even support WiFi unless you added a PC Card.
  • WiFi really sucked back then.  Typical distances were maybe 50 feet through walls, or even up to 100 feet with a clear line of sight.  If the signal was blocked by anything brick or metal, simply forget it.
  • Back then, an access point and a “router” (firewall) were two different devices, making WiFi a little bit more difficult to configure, and much harder to secure.

At the time, the company I worked for sold software and consulting services for financial institutions, and it was normal for our company to have a booth at one of several technical or trade shows throughout the year.

One of the guys who worked some of those trade shows came to us and said “Normally, we get a single ethernet connection for internet access, and if we bring a router [firewall], we can at least share a single connection, but all these cables make it prohibitive to do anything productive.  Can you guys think of a way that we could plug something in that would allow us to all use WiFi instead?”

One of my guys came up with the idea to get a router, an access point, some cables, a power strip, and some WiFi PC Cards, put all of it in a box, and pre-configure everything so that all you needed was power and ethernet.

We even had an extra-long uplink cable so that the box could be located almost anywhere, allowing you to be able to optimize the position of the AP to get the greatest coverage.

The only thing left was to figure out how to ship this thing across the country, repeatedly, without having to package it each time.

At the time, you could get a padded, hard-sided camera case for about $200, which was not going to fly, since IT was paying for it, and we had virtually no budget.

So we went to Wal-Mart to see if we could improvise.

After looking through almost the entire store with no luck, we happened to be in the sporting goods section, and what do you know?  There’s a hard-sided, padded pistol case, with briefcase-style combination locks for about $20.

And that’s how I came to expense a gun case.

Of course, the poor fellow in Accounting who processed my expense report saw the receipt, which clearly stated “gun case” and was rather alarmed.

After a quick explanation, we showed him a picture of the case with the equipment inside, and everything was fine.

He did say that this was one of the most unusual expense reports he’s ever processed, but not THE most unusual, and you really have to wonder about that.

Because it looked like something that might contain nuclear launch codes, we called it the “Wireless Football“.

After a few faithful years of service, all the cables and PC Cards were looted by another department.  By that time, it was kind of unnecessary, because most venues were starting to offer free WiFi and most devices had built-in WiFi cards.

We ended up re-purposing the router and AP to build a home VPN lab.  The case sat around for quite some time, and I think we even used it a couple of times to ship equipment.  Eventually it disappeared – either “appropriated” by another department, or thrown away during one of the many equipment purges.

 

[Edit 2/15/2020]

Thanks to Aaron for the pictures!

Wal-Mart Pistol Case

 

Router, AP, PC Cards (in box) and cables

 

WiFi PC Cards packed individually for transport