Wide-Baseline Stereograms

Thanks to all who attended our first stereo photography class, it was a great turnout with several new faces! If you attended, here is some content that I just created that you can view using either the anaglyph glasses or parallel-viewing stereopticon that you received, or if you have been practicing up on your free-viewing, you can use the cross-eye method or “look-through” method (just set the 3D settings appropriately towards the bottom of the video on YouTube). I’ve created a slideshow of 3D images captured using wide baselines — in other words, the two photos making up each 3D picture were taken very far apart, much farther apart than the distance between a human’s eyes.

So, why wide-baseline? Well, the sense of depth from stereo vision is highly nonlinear, so we generally have exceptional depth perception up close (within a few inches or feet), but we are able to differentiate less and less as the objects get further away. In everyday life our depth perception due to binocular disparity is basically limited to around 20′ or so for most practical purposes. (This is why 3D pictures of landscapes are usually extremely boring and flat — the subject is too far away to make out the depth!) However, it is possible to overcome this limitation by moving the two cameras (one for each eye) farther apart. Some of these images were taken from airplane windows hundreds or thousands of feet apart, making it possible to discern depth between cloud layers many miles away. This tends to produce an effect that is similar to examining a miniature model of the subject up close.

Most of these 3D pictures were captured with the video camera on my phone while on a moving platform (train, car, airplane, etc), with the camera held very still up against the window and facing directly out. I would then open up two copies of the captured video side by side and use the cross-eye method to find two frames of the same subject that provide good depth. I would then copy those frames into Gimp, align the images and crop them down to produce a finished stereogram. It takes time and practice but it can produce some really cool results!

Boats outside Dave & Buster's on the Delaware River. Click to view entire slideshow

 

A few months ago Enrique Muyshondt (President of DesktopFab, aka Endeavour on IRC) gave us a set of Sells Mendel parts that he had cast for our work on various research projects at UPenn and here at Hive76. We slowly assembled it and got it running, and thanks to this past weekend’s RepRap World Tour stop in Baltimore, we have it running! In addition to 3D printing like a champ, we’re now using it to work on the firmware and customize printing scripts for tissue engineering research. We are grateful for the support!

The parts are cold cast bronze, this means Enrique painted several layers of bronze powder into his molds and then cast them with resin. What came out were the brown parts you see in the pictures and video below.

This 3D printer rocks. The RepRap 3D printing project still has a lot of rough edges, but that’s why we love it. We’ll have BronzeBot on exhibit at the next RepRapWorldTour in Baltimore, and then back in Philly in August to do it again.

Slideshow:

 
Sorry to everyone for how long it took me to get this write-up out. The perils of starting a new job, I guess. Luckily, we had plenty of notes taken for the entire week, so very little was lost to the black hole that is my memory.
Our arrangements for Philly Tech Week were pretty impromptu, but we managed to pull off a number of fun things.

Monday, 25th: Open Work Night
Open Work Night turned out to be an extension of our spring cleaning from over the weekend. We got the space nice and tidy for everyone who would be visiting later in the week. One visitor came by and helped us put together a few shelves, which was incredibly handy as they required some “lite modification” with a hacksaw before they would fit in our ceilings. Oh, I know! Our ceilings are freaking tall, what was up with the shelves?

Tuesday, 26th: Micro-controller Show and Tell
The evening had a pretty light showing as people hadn’t really quite caught on to what we were doing. However, some of our members (Mike, Chris, and PJ) did get a start on a mirror-and-laser text display system. Very cool.

Wednesday, 27th: Regularly Scheduled Open House + Late Night Karaoke
On Wednesday night, we hosted a number of guests for what is normally our Open House night. These normally turn into social gatherings of sorts, and Tech Week was no exception. We found out that one of our guests is getting ready to launch a new social networking site, another who has started a vending machine company focusing on local goods (http://snacklikealocal.com), and another kind soul looking to donate a Smithy Lathe!

PJ got his MIDI Nintendo Running pad working. Basically, the old running pad controller used with the NES is interpreted through an Arduino to send MIDI signals back to a host computer, where it is used with any MIDI capable software, in this particular case Ableton Live.

We did get Late Night Karaoke going, and it was a blast. Adam rocked out with the Darkness’ “I Believe in a Thing Called Love”. Sean sang Gershwin’s “Foggy London Town”. PJ wooed everyone with The Temptations’ “My Girl”. Corrie set us all rolling laughing with Gayla Peevey’s “I Want A Hippopotamus For Christmas”. Chris fiiiiinaly got up to sing Soul Survivor’s “Expressway To Your Heart”. And Brendan was Brendan with Rick Astley’s “Never Gonna Give You Up”.

Thursday, 28th: DIY/Electronic Music
We had a good mix of newcomers and members for our music night. One person brought in a completely hand-made, 7 sting electric guitar he built. The thing was sick, really wish we had gotten pictures. We jammed out with various synths and drum machines. Sean further extended his Atari Punk Console with a low-pass filter to give it a rounder tone, then blipped and buzzed along with everyone else. Brendan rocked out on the guitar, and Dan was really tearing it up on the keyboard. Definitely a fun night, and we will be looking to do more such nights in the future.

Friday, 29th: “Bricks and Grips” – Arm Wrestling/Puzzle Game Tournament
This night, we actually had more guests than members show up. The first two challengers for Arm Wrestling Tetris were Sean McBeth (the creator) and Robert Cheetham, founder and president of Azavea, a GIS software firm in Center City that is doing some extremely revolutionary work (I know, I used to work in the industry). We also had a bit more electric music jamming, which was a great time.

It was a real team effort getting the game together, between Brendan’s sound track, PJ’s voice over work, and Sean’s programming and construction, it all fit together perfectly. Next up, Punching Bag Double Dragon!

Saturday, 30th: Artemis Game Session
The developer of Artemis just released a new version that includes canned missions. We played the first mission with Sean as Captain and survived to tell the tale.

While en route to our primary mission objective of observing anomolies in a nearby nebula cluster, we encountered a squadron of Krellians lying in wait, having prepared for an ambush against us. Lt. Commander Santoro showed great skill and initiative in destroying the three ships in mere seconds with two well-placed nuclear torpedoes.

After the brief battle, we intercepted a distress call from Deep-Space 49 as they took fire from another battle group of Krellians. Running low on energy and weapons, we barely scraped by and defended the station after a core-burning sprint at maximum warp that nearly left us depleted of energy. Lt. Peterson performed admirably in her duties managing power levels and surely is responsible for our survival.

DS-49 provided us with much needed supplies as we returned to our primary mission: scanning nebulae. We returned to the cluster to find another hidden flotilla of Krellians. This time, we were completely out of nukes and were unable to deal with them handily as we did before. We managed to warp out of weapons range before any serious damage came to the ship. Our second sortie against the Krellians fared better, we damaged them, but had not completely destroyed them. Running low on weapons, Commander Toliaferro performed commendably in maintaining a flanking position on the enemy, allowing Lt. Commander Santoro to dispatch the enemy with beam weapons.

Completely depleted of forward torpedoes, running low on energy, we were ambushed by a third squad of Krellians while under way to DS-45 for supplies. While we managed to warp into a nebula for cover, the nebula destroyed our shields and we were stuck with the enemy between us and our safety. Having nothing but mines left, Captain McBeth hatched a plan. We would fly through the center of the squadron, diverting repair crews and energy to protect critical systems as we bore the brunt of the frontal assault, then dropping our mines in the middle of the squad as we passed through them, to warp away to safety on the other side. The plan required a high level of coordination by all crew members. As Commander Toliaferro deftly navigated at close quarters through the heart of the beast, the first pass dealt great damage to the enemy, but they weren’t quite finished. Rather than coming about for another pass, Captain McBeth ordered all-stop in the middle of battle. Allowing the enemy to come in to weapons range, Lt. Commander Santoro dropped the last few mines, while Lt. Peterson delicately balanced the needs o the repair crews, shields, weapon systems, and engines largely under instinct, not having time to run the proper load balancing calculations. As a result, the final Krellian fleet was completely destroyed while the S.S. Artemis flew home under her own power, completely undamaged, back to DS-45.

Another mission accomplished.

 


Update: Online ticket sales are closed. A limited number of tickets will be available tonight to PAFA members and those who want to sign up for membership.

The other day, Sean mentioned that we’re helping with the Pennsylvania Academy of the Fine Arts’ After Dark event this Thursday 3/31, called “Grossed Out”. Here’s another teaser.

PAFA has been opening up their beautiful, cavernous spaces on North Broad Street so people can get down with music, drinks and hands-on diy projects, all surrounded by super classy art. This Thursday’s event, Grossed Out, celebrates the famed “Gross Clinic” and PAFA’s new exhibit Anatomy/Academy. The exhibit examines “how Philadelphia’s dynamic art and science communities… fostered knowledge of the human body… transformed the attitudes of the public towards mental and physical health, and challenged conceptions about beauty.” Music and body-bending entertainment are courtesy of the Olde City Sideshow. Yes, glass eaters at the Academy!

Hive76 and The Hacktory are building four (!) different activities for this Thursday’s event. The Hacktory has posted some updates on our progress. Here are descriptions of the activities:

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We got a mention on CultureMob.com for our upcoming participation with PAFA at their next After Dark event.

 

D-I-Y DCP Creation using OpenDCP

[Editor note: This is a guest post by the wonderful Chris Young. He’s making his own 3D short film from the ground up. -eagleapex]

terminal
My goal was to make OpenDCP work on a Sony SRX R-320 and after numerous attempts — as an independent filmmaker, I am elated to say it worked perfectly! It wouldn’t have been possible if Terrence Meiczinger hadn’t developed OpenDCP.

Admittedly, a few weeks ago I didn’t know much, if anything, about creating DCP files… let alone a stereoscopic 3D-DCP. I had recently finished work on a self produced and directed short film, “Dead of Nowhere”, that I was able to make largely in part utilizing the crowd-based funding site Indiegogo. I used a Final Cut Pro / 2K Cineform workflow to edit and finish my film. I shot my film guerilla style in one day, handheld on location with the Element Technica Dark-Country beamsplitter rig, recording to a 1-Beyond Wrangler. When I learned that it was going to cost somewhere between $1,500 and $3,000 to have my ten minute film encoded in order to have it shown in a realD™ equipped theater, I knew I had to find an alternate “indie” solution to create my DCP.

After investigating all of the commercial solutions (easyDCP, Doremi, etc.) and speaking with several “indie-friendly” post houses — all of whom bid out of my price range… I stumbled onto OpenDCP.

While the notion of using an open-source command-line tool, still in development, isn’t for the faint of heart, and I am by no means a Unix Pro, the process was pretty simple once I understood how the OpenDCP tools worked.

There have been plenty of how-to posts, so I won’t get into a lot of detail here… but basically after getting my film into a Left Eye / Right Eye TIFF sequence at the correct aspect ratio (1998 x 1080), the frame rate at (24p), ensuring that my audio was the exact same length (intrinsic value) and the correct sample rate (24bit), it was a fairly straight forward process to convert to XYZ jpeg2000 (.j2c) using opendcp_j2k and then using opendcp_mxf to wrap the stereoscopic-picture and main-audio elements into separate mxf files. After figuring out that I needed to be sure to have the digest (-d) and annotation (-a) tags set in opendcp_xml, it was then just a simple matter of getting these files onto a drive to load into a cinema server.

Now, don’t get me wrong, this will probably not work the first time. I had to make several trips back and forth to the theater, trying various DCP versions (interop and smpte) and hard drive formats (I settled on NTFS).

If you’re an indie-filmmaker, trying to get your film digitally packaged for exhibition and don’t have the money to spend, or are the kind of person (like me) that enjoys learning about every step of the process — I couldn’t recommend a better, more rewarding way of creating a DCP.

More information about OpenDCP and DEAD OF NOWHERE can be found here:
OpenDCP Link: http://code.google.com/p/opendcp/
Short Film: http://www.deadofnowhere.com
Facebook: http://www.facebook.com/deadofnowhere

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Hive76 is well known for sparking groundbreaking ideas. In the last year alone, we have been the home base for innovating products such as the USB Typewriter, Meatcards, Boomcases and Math Clocks.

We are proud, tonight, to continue this tradition. We would like to congratulate long time Hive76 member Adam Kaufman, also know as Adam[0] on IRC, for joining the ranks of our elite.

Take a bow Adam. You’ve earned it.


inventor

photo courtesy of fynflood

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Gitmarks 2.0 Alpha

As rumors of delicio.us shutdown rumbled through the internet, a bunch of geeks in a minor IRC channel started gabbing. They has a lot of info, links, tags, and data stored in delico.us, and were afraid to lose them, syncing, and all other good features. They realized as geeks often do, that if we owned the service, we wouldn’t have to worry about outside shutdowns if we had our own service. Thus hypatia spun-up Federated Bookmarks

The first output of this crew is something called gitmarks, based on work by Hillary Mason (of bit.ly). This is a little tool to store bookmarks, bookmark metadata, and page content locally for searching, using, and peer-to-peer sharing. Since it is based on git this system can use a central server, *or* it can share peer to peer. As the name implies, it uses a git backed for data transfer and versioning. It also has the ability to pull down content for a local cache, and for local searching.

This project is in Alpha, and if you want to test the silly thing, the basics work. If you want to help build a cool distributed tool, we could use some help! We need to building a server, building more git tools, xmmp messaging, and browser integration. We also hope to create tools that along the way that make it easy to build systems for Moglen Boxen. Ping FarMcKon@gmail.com, leave a comment here, or hit #hive76 in IRC if you want to help.

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Adam K. works on getting axis movement on the RepRap Huxley

Back in 2009, we ordered our first 3D printer, the MakerBot Cupcake. Since then, we’ve become pros at fixing, modifying, and mostly breaking it. We’ve even created new, awesome products for it which have been adopted by a good portion of the 3D printing community, and even sold by MakerBot themselves.

Shortly after completing our Makerbot, once-member fynflood decided to start building the RepRap Mendel, which is the 2nd generation of the RepRap Project’s 3D printer. He started by printing all of the pieces on our MakerBot, which took over 20 hours to complete, and gathered all of the required hardware with help from many of our members. A printer was born out of Hive76, and life was good. A few months later, there was a post on the reprap aggregation pipe about a new iteration of the reprap, called the Mendel Mini (now the RepRap Huxley), which has a similar build volume to the MakerBot, but can be assembled for under half the cost. Fynflood set out to print the parts on his Mendel, while I gathered all the required hardware and electronics. After a few months break over the summer, and a few more months being busy with the Holidays, the Huxley is now complete! Our printer’s baby made a baby!

At this very moment, we have 2 MakerBots and the Huxley all going at the same time at the space! If any more printers show up, we’ll probably have to start giving away USB Typewriters just to make room! Really, it’s an exciting time to be printing at Hive76, so if you have any interest in learning how 3D printers work, or even building your own, come by for open house on Wednesdays and check out all the awesome things we’re making!

Hit the jump for a few videos and images from the first few prints!

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Paper legos from 3D-printed mold

molded paper legos

Mold 3D printed in PLA

At open house on Wednesday I printed a LEGO ice cube mold and filled it with paper pulp. The objects you see here is the result. Improvements: smooth the sides of the mold so it’s easier to remove the paper.

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