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Posted by Jack Crossfire | Oct 12, 2017 @ 05:12 PM | 1,839 Views
Stanford students during the longest economic boom were philosophizing a lot more than during the recessions. It was much more crowded at 8pm than it was, many years ago. Steve Jurvetson was mingling with students with stars in their eyes, supposedly members of a class he taught. This was the generation which would fill SOMA in the coming years while the rest of us drove the taxis their mobile apps dispatched.


He swaggered into the parking lot, taking a picture of the line of space fans which would disappear forever into his iCloud account & never be tweeted of course. Lions supposed as he got older, Jurvetson had to diverge from the wild cards like SpaceX which made him famous to more on target startups in pizza delivery & philosophy. The days of guys programming registers in basements were over. A modern entrepreneur was a philosopher. Steve was now keen on fitting in that crowd.


The presentation was the standard boilerplate. Shotwell seemed a bit more specific than past videos. The questions were the standard big pictures, nothing technical, manely from Steve & nothing from the lion. Though there was no new media on the BFR nor the layout of the 1st stage engines, she did say the 1st full size Raptor was under construction, a new factory was going to be built rather than converting the Hughes factory, & they were now heavily focused on BFR development.


The amount of dialog & urgency on such a far fetched spaceship was most...Continue Reading
Posted by Jack Crossfire | Oct 11, 2017 @ 12:57 AM | 1,785 Views
A 3rd rework put the camera as high as it could go. This required putting the fan under the camera & pointing the soft lens forward. A bit more effort could rotate lenses by rotating the entire assembly. Because the fan was underneath, the only way to give it airflow was to mount the protection farther away. It's not protected from a diagonal fall, but is fully protected from axial & sideways falls. Fortunately, no vehicle has ever flipped over diagonally. They've manely fallen sideways. The gopro death was an axial fall from accelerating.


It's reasonably unobstructed. What happens next is already known from decades of making camera systems. The test movie is too shaky to be useful so stabilization in the spherical domane is developed, over months & years. For now, the frat houses provide stabilization of spherical videos when played in a viewer but not equirectangular mode. There's unoptimized, 2 year old source code for doing it with mobius transforms.


How times have changed from 20 years ago when any idea had a recent example in source code.
Posted by Jack Crossfire | Oct 08, 2017 @ 10:00 PM | 1,757 Views
After much planning & other tasks needing the camera, the imagination once again became aluminum & duct tape. It's 1ft lower than last year's pole cam. A minimum amount of protection from falling on the lens was devised, which would obstruct as little of the view as possible. The good news is the current generation is used to seeing equipment & seams in a spherical photo. The camera needed more spacing below the cross to avoid being totally obstructed. A gopro could be mounted above the cross.
Posted by Jack Crossfire | Oct 08, 2017 @ 04:24 AM | 1,824 Views
Making a modular, elevated camera system for a rover has been as problematic as it was for copters. Right away, the h-king is too small for a pole cam. The pole needs to be lower than last year's experiments because the Gear 360 is heavier & experience showed the need to protect it. Any method of protecting the sphere cam is going to obstruct some of the frame, but a method using 2 sticks might protect it from a fall in any direction.


The sticking point is now attaching the pole to the vehicle. A sheet of material bolted to the vehicle is a real pain to install. A metal X is a leading contender. Then, the pole is simply lashed to the vehicle handle. It won't need guy wires because it's lower. Stabilization is nowhere on the radar. Getting good video has always required a larger vehicle than the budget allowed.
Posted by Jack Crossfire | Oct 06, 2017 @ 04:24 PM | 1,882 Views
20 years after the lion kingdom hatched the idea, someone finally used a 55" TV as a computer monitor. Doubt it'll last, because it's immediately obvious that he can't see the entire screen behind the clutter. There's no airflow. He has to sit too far away to see normal fonts. The DPI is 100. Not all programs scale to larger DPI, so 55" is the smallest 4k display which can display legible fonts.


It's cheaper than the 30" monitor lions have been using since 2008. A younger lion would have sprung for it & watched movies in fullscreen, in a dark room, in 1 shot. An older lion is concerned with practicality & only watches segments of movies in a window. The time spent watching movies in 1 shot has long been dedicated to the commute.
Posted by Jack Crossfire | Oct 06, 2017 @ 02:31 AM | 1,592 Views
2 years after the Accucel's 1st surgery to break out the balancing header, it was time to replace the buttons, which had manely stopped working. They graciously exposed all the buttons on a header. It merely entailed breaking them out on a very long ribbon cable. The 12 year old buttons from Heroineclock 1 were installed. They were heavily rusted. 2 of them didn't work. Fortunately, had another 2 buttons from a camera remote of long ago. They used to be a 30 minute run to Radio Shack. Now, the only way to get more of those is a 2 week order.


The Accucel's LCD is still broken, but hasn't degraded. It may end up being reverse engineered & replaced by a converter to drive a larger LCD. There's no evidence of what part it was, but it only has 4 data lines. It's been such a waste of time repairing this $35 antique, the process might as well keep going.
Posted by Jack Crossfire | Oct 01, 2017 @ 04:45 PM | 1,743 Views
In documenting airplane interiors, it quickly became obvious just how bad the Gear 360 is. Basically, it's useful for spherical video but only photos in a pinch.

Vintage F-16 cockpit:

https://www.flickr.com/photos/152533...posted-public/

Vintage C-130 cockpit:

https://www.flickr.com/photos/152533...posted-public/

https://www.flickr.com/photos/152533...posted-public/

C-130 cargo:

https://www.flickr.com/photos/152533...posted-public/

https://www.flickr.com/photos/152533...posted-public/

Vintage airplane cockpits are quite dear, because once they're scavenged & sent to the boneyard, they're gone for good.

The instrument details are completely lost, except for the flight engineer panel directly overhead, but it was sheered by the lens gap. The Gear was on a tripod with the intention of mounting it stationary in the middle of the cockpit. In reality, it would have been better on a handheld pole. The tripod was never used. Shots from the 4 seats close to their respective instruments would have been the best this camera could get.


Cargo planes have detail above & below, so something is always sheered. Objects are close & closer, making the parallax always sheer something. Fighter planes have detail only below. It would have been best to have the lens shear bisect between the canopy & instruments. Even better: have the N & S poles face the sides. There's still no obvious way the Gear 360 could have resolved the F-16 instruments.

The best quality sphere photos are still taken by a guy shooting a DSLR in every possible direction. It might be on the end of a pole, with exposure bracketing. The next highest step is a robotic mount. The next step is a Gear 360 on a pole. For airshows with large crowds waiting in line, there are probably better ways to utilize the Gear 360 like pointing it in different directions to defeat the sheering line.
Posted by Jack Crossfire | Oct 01, 2017 @ 01:57 AM | 1,763 Views
Kind of fitting after China declared its J-20 stealth fighter operational, the F-22 broke down during the demo. It flew much closer to the audience than the fleet week demo, which made it much harder to get in frame. It was very frustrating to hear it more than see it, since it was never in frame when you looked in the viewfinder & already gone by the time you looked away from the viewfinder. All the tents made it impossible to see before it was right in front.


After only 4 passes, it malfunctioned & had to land. The audience immediately left without waiting for the heritage pass. Being an airshow announcer must be a hard job, starting the narration while the seats are still empty, announcing hours of demos no-one cares about, & announcing the heritage pass after the F-22 broke down, while watching everyone leave.


Other than the mane attraction, the military cargo planes were all in Puerto Rico & there was no Thunderbird demo. The audience was clearly not having any of it & just waiting for the F-22.
Posted by Jack Crossfire | Sep 29, 2017 @ 04:08 PM | 2,132 Views
"We will start construction of the 1st ship around the 2nd quarter of next year."

Like something from a movie about averting the destruction of the human race. Pretty intense stuff, but lions are pretty sure you can't test the in situ propellent plant for the 1st time on the same mission the 1st astronauts are going on. As expected, it was lighter than last year's show because of the renewed focus on their mission backlog instead of the BFR.

Delta wings are back. It has assumed the familiar shuttle shape. At least the shuttle designers got that part right. Unfortunately, he couldn't make the heat shield reusable. They're not going fly around with enough material to make it reusable. They're going to spend a huge amount of money replacing it for every flight.

He didn't show the engine layout of the new 1st stage. Perhaps the BFR guy focused on just the new 2nd stage & he only has a rough idea of the new 1st stage.


Unlike last year's design, the current design looks like it could actually happen & he was clean shaven which added more credibility. The payload is now 1/2 of last year's. The timeline is the same as last year, but he's able to do it in the existing factory.

Using a BFR to fly around Earth is a bit silly. The Concorde already proved no-one cares about high speed air travel, so he's not going to make money on that. The security lines & boat trip to the launch pad will comprise most of the time. At least it would...Continue Reading
Posted by Jack Crossfire | Sep 28, 2017 @ 12:57 AM | 1,845 Views
In the quest for a use for the Gear 360 & all the work that went into it, some more tweeks to the pointless spherical camera software have revealed some documentation of a vehicle to be retired next year. The next step is spherical images of the interior, which weren't possible with the mob.

C130P #66-0219 (0 min 30 sec)

Posted by Jack Crossfire | Sep 22, 2017 @ 01:45 PM | 2,390 Views
The answer is no, you can't align the rear wheels. They're doomed to wear out from being toed in. The tires can't be removed. H King sells an alternative set of wheels with removable tires. The rear wheels can't be swapped with the front wheels.
Posted by Jack Crossfire | Sep 16, 2017 @ 11:26 PM | 1,984 Views
It was assumed when the treads wore down, the bald tires wouldn't wear anymore. A quick examination of the tires revealed the bald parts were still wearing down & were looking like a Mars rover. So they were moved to the back, which had shown very little wear. It would have been better if they were rotated sooner, but it only means a new vehicle is going to be required before 2 of the tires are worn out.


After another 15 miles, it became clear that the front tires wore down because they have a slight toe in. The good news is the hubs didn't slip inside the rear tires, anymore. Slippage is a function of the rubber wearing out over time, as the tire wiggles ever so slightly when the motor starts.

http://solarxploration.wixsite.com/concepts/images

has some more space artwork. There are a few disasters like the ITS being made of riveted aluminum instead of carbon fiber, wind surfing & jet suits on Mars.
Posted by Jack Crossfire | Sep 16, 2017 @ 04:06 PM | 1,964 Views
Flickr has a reasonable viewer for spheres, but none of them can zoom like the QTVR player we had 25 years ago.

https://www.flickr.com/photos/152533...posted-public/

This one has the moon overlaid on the 60 frame average, giving the best approximation of what it was like. Unfortunately, flickr doesn't allow fullscreen viewing.

https://www.flickr.com/photos/152533...posted-public/

Made another eclipse video where footage of the moon from another camera was inserted where the Gear 360 couldn't resolve anything. It's far from a perfect spherical mapping, but it's quite effective in 4k. The bitrate was also doubled.

Eclipse in spherical mode with moon visible (4 min 18 sec)

Posted by Jack Crossfire | Sep 14, 2017 @ 04:23 PM | 2,090 Views
Musk dealt a crushing blow to the 5 guys who read about the space program. A lot of us were hoping the current wave of civilization would go beyond the Saturn V, but in 1 tweet, the Saturn V became the largest we would ever get.

The revised BFR would have 21 instead of 42 engines. The work invested in building a mock 12 meter tank last year goes away. The good news is waves of civilization only take thousands of years instead of millions. The successor to Saturn V could be 4000 years away.

The only savings are the factory & the assembly building. A new barge & launchpad still have to be built. He would find a way to stack it horizontally. It's obvious that in order to free up room to build the mini BFR in the existing factory, they're going to dramatically slow down Falcon 9 production & reuse the existing inventory. Suspect block 5 will be the start of almost every customer flying on a used booster.

The 21 engines would make 10 million lbs of thrust instead of 29 million, slightly more than the Saturn V, in a smaller package.
Posted by Jack Crossfire | Sep 13, 2017 @ 01:04 AM | 2,541 Views
A fusing of the very 1st Gear360 video was quite accurate, all the way to the bottom. This had the camera horizontal.
A fusing of the camera rotated sideways was also nearly perfect, all the way to the bottom.


The leading theory is grinding the lens down may have tilted the plane of focus so objects on 1 side are farther away than objects on the other side. This can probably be corrected with a pile of new parameters.

Another problem was vignetting causing the boundaries to look dark.

Eliminated the radius parameter from the Bourke equations, since it only scaled the field of view. Fusing now took only field of view, input XY, & Z rotation.


Uploading it to the goo tube requires tagging it. The goog has source code for tagging it & reading the tags. It's a python program which works on all operating systems. Merely run 'python spatialmedia -h' in the root directory.


https://github.com/google/spatial-media/releases


Unfortunately, it couldn't handle files containing mp4 audio. Despite being written 16 years after libraries for reading Quicktime/mp4 started appearing, he still wrote a custom parser which doesn't work. Such is life in a world with every program written in a different language.

The decision was made to hack the lion kingdom's 19 year old make_streamable program to inject the header while also moving the headers to the start of the file. It'll never pass a Goog job screening, but it works. It was hard coded for equirectangular with 2 channel audio. The hardware is around for making 4 channel audio, but the standards are very complex.

Eclipse in spherical mode (4 min 18 sec)


It has some potential on the day job's ipad pro. It's almost worth buying VR goggles to experience that moment again. The Samsung's inability to resolve the moon was a disaster.


To get flickr & facebook to show spherical photos in a viewer, use exiftool to add the magic tag.

exiftool -ProjectionType="equirectangular" photo.jpg
Posted by Jack Crossfire | Sep 10, 2017 @ 08:20 PM | 2,106 Views
After many days of searching, a legit looking source appeared.

http://paulbourke.net/dome/dualfish2sphere/

http://paulbourke.net/dome/fish2/#fish2pano


Of course, like most things these days, there's no source code for a complete converter. There's just enough source code to develop a converter from scratch. More clues come from a list of command line arguments required to stitch the images.


Using standard image processing techniques, the equations finally yielded a proper equirectangular projection. Without the benefit of automated control points, a lot of manual tweeking got the horizons to line up, but failed to align anything above or below. It definitely wasn't parallax distortion. The right eye needed to be rotated in the opposite direction for the bottom to line up. It would be impossible to align the images without a GUI giving instant feedback.


The field of view can be adjusted by getting objects on the horizon to line up horizontally. It's not clear how to adjust the radius. The center XY parameters he provided are the input coordinates of the fisheye. He then provided XYZ rotation parameters which appeared to transform the input coordinates. Because the rotation & center parameters feed back into each other, it was impossible to get very far that way.


It was easier to make the X & Y rotation apply to the output & make center X & Y where to capture the input. Z rotation still worked by transforming the input coordinates.


The next step would be finding a decent viewer besides the goo tubes. Lions prefer watching spherical videos as equirectangular projections, but there's no way to know if the projection works without a viewer. There's also a new class of effects which apply just to spherical video.
Posted by Jack Crossfire | Sep 06, 2017 @ 02:14 AM | 2,071 Views
The closest empirical equations got was this render. The problem is tangents to the sphere should be horizontal. Here, they only converge. Any horizontal lines are purely from extreme stair stepping of pixels rather than coordinates. Nearby objects don't overlap the way they should. The lenses have to be pretty well crushed, horizontally. Some horizontal compression makes sense, since the eyes overlap.

Having failed the empirical idea, that leaves installing windows, Actiondirector, & photographing test patterns to derive other empirical equations or resorting to mobius transforms. It's the kind of thing vihart would have made a video about, 10 years ago. The generation which used to make videos about math graduated to making families. They were like an offshoot of the generation which wrote open source software as a hobby or to get jobs.

Surprising how times changed so much, the entire VR craze passed without anyone documenting the math behind it, just for the spirit of discovery, the way Alan Cox or someone from that generation would have.
Posted by Jack Crossfire | Sep 04, 2017 @ 05:05 PM | 1,771 Views
Figured no-one would get a 4k video of it, because it was too difficult for the current generation. No-one did, except for 1 Korean professor who came around the world with a very large telescope.


https://petapixel.com/2017/09/02/tot...eid=37b806db54


The panning shot was fully automated. It claims to have an accoustic reduction gear but uses a DC motor, so it could be a bit of marketing wank. In the automated pan, it's remarkable to see the detail of the moon's mountains & the entire firey surface of the sun. Only with a shade in space can these details be seen. The atmosphere scatters too much light from the sun's center for a ground based shade to work. It makes it almost worth getting a 4k monitor.



Among other predictions, no-one got a locked down timelapse from a quad copter. No-one got a 360 video from a mountain top. In the coming weeks, a few other timelapses of Mount Jefferson appeared which were better than the lion kingdom's.


Solar Eclipse 2017 - Mt Jefferson Oregon. Time lapse (0 min 23 sec)


For some reason, people don't know how to upload higher than 320x240.
Posted by Jack Crossfire | Sep 03, 2017 @ 07:02 PM | 1,875 Views
The stitching plugin is an ongoing debate. Actiondirector just works. The original idea was not creating proper spherical projections but something more visually appealing which the user could watch without panning. Then, spherical projection became necessary because that's what every program should do.

Doing it properly requires mobius transforms. Cinelerra can do it emprically, using just trig functions, but it lacks the more advanced manipulations. So far, just scaling X coordinates by a secant function gets close to the spherical projection, but is still pretty bad.



In the years since VR lost popularity, much progress has been made in spherical anaglyphs, virtual camera blocking, rotating spherical projections. The mobius transform is implemented with some kind of ray tracing. It would have to be optimized into trig functions or made into a lookup table.

Only Actiondirector can apply the IMU data. Samsung didn't write Actiondirector. It was marketed by Cyberlink, the same Cyberlink which marketed the 1st fully licensed, region locked, menu supporting DVD player for computers, in 1999.

On Linux, there's an expensive KartaVR plugin for Blackmagic Fusion. There's Ptgui which is an emprical process but doesn't seem to work. There's the expensive Autopano for Windows.