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Steganography 101

Disclaimer : This is a blog post about a CryptoParty presentation, the contents of which should not be construed as official Freeside statements.  Any opinions presented in this blog post by the author do not in any way represent an official endorsement of these opinions by Freeside Technology Spaces, Inc., nor is intended to reflect the views of Freeside and its membership. Recently, Freeside hosted a CryptoParty where I gave an introductory presentation on steganography .  Like all my CryptoParty presentations, this wasn't very technical, but I did introduce some (very) basic techniques. The first tool that everyone should know about is exiftool .  exiftool reads and writes to the metadata section of a variety of image formats.  I showed an excellent illustrated example of Exif metadata in the JPEG format, which has some great diagrams which show how a JPEG file's bytes are laid out.  There's also C# .NET code included to extract and modify this data, if perl'

The Motobrain Story

Motobrain began when I decided my options for a vehicle fuse panel where too limited. I wanted something better. A buddy and I started chatting about what we might want from a fuse block and I started drawing schematics and making prototypes. My first idea was an actual fuse panel that could measure system voltage and total current draw and had fused circuits. It's "killer" feature was that all the outputs were interchangeable so you could select the type of output you wanted. It had card slots and the card slots and the cards I developed with for high side switching, low side switching, USB charging, and analog inputs. It was cool, but not really durable enough for an automotive environment.   It was going to be controlled from a dedicated unit wired to the gizmo above. The more I thought that through, the more that was foolish since we all have computers in our pockets already, our smart phones. So I did a full reboot and decided to do a Bluetooth 4 gizmo, that

Manual Pick and Place project

I built a pick and place machine so I could build up my Motobrain project easier. I used MDF for the platforms. 12mm rail and linear bearings for the Y and Z axis bearings. THK linear motion guide for the X axis. The Z axis is a piece of carbon fiber tubing attached to a piece of laser cut acrylic. The nipples on the tube are 3D printed.  The laser cutting was done by OSHStencils.com. The bearings were purchased at Amazon. The 3D printing was done by approto.com.

Lathon 3D Printer

Everyone seems to either want, have or use a 3D printer now a days. I bought my first printer kit in 2012 and I quickly noticed I wanted a one with more capabilities but since all of the high performance models were so expensive I designed my own. Eventually I designed a $4,000 printer that I could sell for $1,400 on KICKSTARTER . There were a few things that I wanted the printer to have: two nozzles, Bowden extrusion, enclosed build area, and a moving xy gantry.  The two nozzles seems like an obvious choice for anyone who has printed before simply because it allows you to create way more interesting prints than you could otherwise. For example dissolvable support, multiple colors and multiple materials (which is pretty cool). I did notice on other dual nozzle printers, however, that having two big stepper motors created a massive moving mass so if I wanted any sort of respectable speed I was going to have to go Bowden style. Another pet peeve I have is

Thermal imaging macro photography on a budget (sort of)

I purchased one of the new FLIR E4 thermal imaging cameras  (TIC) a couple weeks back because I am working on a new project called Motobrain . It is an automotive power distribution unit with a nominal current capacity of 100A. For those not in the know, 100A is a TON of current! Because this project is designed to move so much current and will be small I need to understand its thermal characteristics very well. To that end I've been operating the device and taking measurements. What I found is that I just could not get the kind of detail I wanted. The reason is that the resolution of the  microbolometer  in the FLIR E4 is not very high and the lens does not allow you to get very close to the device under test (DUT). The means that you cannot just zoom in after you take a photo either. So, what is a person to do if they want to take a macro photograph with a consumer grade TIC? Go to Amazon.com of course! I purchased a Gallium Arsenide (GaAs) lens meant for a CO² laser for about $4

A Portable Storage System for Dead Tree Information Storage (Bookcase)

I (Ben Bradley) have made several of these for my personal use. My early bookcases were three feet wide, but moving was a process of putting books into boxes, moving the shelving and the boxes, and putting the books back on the shelves. It was unknown whether the bookcase would hold together if tilted while fully loaded, because it was too heavy to pick up when fully loaded This one was assembled at Freeside after the November 5 Open House and is based on my current design, as follows: Components used (available at any Home Depot or Lowes): (4) 1" x 8" x 6 ft pine board (actual measurements 3/4" x 7 1/4") (1) 4 ft by 8 ft. x 1/4" plywood board. (48) 2" long wood or drywall screws, coarse thread preferred (about half of a 1 lb box) (30) 1" long wood or drywall screws, coarse thread preferred (about a tenth of a 1 lb box) Tools used: Chop saw, table or circular saw, hand sander, electric drill/electric screwdriver (two preferred, one for

How we built the Infinity Portal

Some of you may have seen our most recent monster creation at Alchemy or Atlanta Mini Maker Faire - The Infinity Portal. The Infinity Portal is a 10 foot tall archway with a 7 x 4 ft infinity mirror inside of it. The mirror is made with two-way acrylic, so you can push on it to warp the effect for people on either side of it. It is lit with addressable LEDs, so there is a counter-rotating rainbow vortex in there too. You may remember seeing our write-up about prototyping the design a few months ago. Defying all expectations, the thing actually survived both events that we brought it to! So we're really happy with it and will find a place to keep it in the mean time. We actually (surprisingly) did a pretty good job of documenting this build, so we cut it together into a video to show how we built this huge, epic piece of art. Enjoy!