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December 28, 2008

Controlling Sony camcorders with the Arduino

The Local Application Control Bus System (LANC) is the protocol used by Sony camcorders (and some other brands as well) that allows external accessories to control the camera remotely. On most cameras, you'll find a LANC port next to your camera's other IO jacks—it's usually a 2.5mm headphone-style jack, or a 5 pin mini-DIN.

If you're an Arduino fan, you can easily create your own custom devices that can interact with your camcorder using the LANC protocol, allowing you to control zoom and record functions from your own programs. Goose wrote about his own project and example Arduino source:

I found source code to do LANC control with the Arduino board. It was written quite well - it worked the first time out. I made a few changes though, specifically changing it from being controlled by a serial port to being controlled by a potentiometer. I plan to build my own zoom controller with it, using an Arduino Mini.

The original code comes from Brady Marks. Make sure to check out the README and other documentation inside the source zip file. Along with the Arduino source, there's a bunch of LANC protocol documentation as well as some collected emails and mailing list discussion on the topic.

Zoomduino - Arduino Zoom Controller
SONY LANC Protocol Details
Brady Marks' Arduino LANC Source

November 20, 2008

Youtube in 720p HD - viewing and embedding

Last week I mentioned that adding &fmt=18 to a Youtube URL, or &ap=%2526fmt%3D18 to the embed code URLs allows you to view and embed Youtube clips in nice looking 480x360 resolution, encoded with the H.264 codec. The result is a much better playback experience than the standard 320x240 sorenson encoded clips, but a post today on webmonkey gives us another tweak that can produce even better results for some videos.

Above is an example of Collin Cunningham's brilliant LED investigation in high def.

By changing that fmt variable to &fmt=22 or tacking on &ap=%2526fmt%3D22 to the embed URLs—that's right, turn it up twice past 11—Youtube will kick out compatible videos at a whopping 720p resolution.

Here's some example embed code:

The only downside to embedding videos this way is that it really raises the bandwidth requirement for viewers. On my home connection, it can take several seconds before the video begins playback, and depending on how well my wireless is behaving, it's not uncommon that the download rate will be slower thank playback, requiring quite a bit of pre-buffering. On the other hand, some videos are just worth the wait.

How To: Watch YouTube Movies in Full 720p HD Glory

November 13, 2008

Embed high-res Youtube videos

Here's an example of a normal embedded Youtube video, borrowed from Patti Schiendelman's Gakken Mechamo Inchworm post.

Back in march, it was discovered that when you view a video directly on Youtube, you could add a "&fmt=18" to the URL to enable a higher quality, higher resolution stream which is encoded with the H.264 codec.

To make this work in an embedded video, however, you need a slightly different hack. After pasting the embed code into a blog post, adjust the two video URLs (one in a param tag and one as the src parameter in the embed tag) by adding "&ap=%2526fmt%3D18" to the end.

For example, the above video embed becomes:

And here's the result:

The still frame before the video is played is the exact same over-compressed image, but when a user clicks play, they will get a nice surprise. Instead of 320x240 video encoded with the Sorenson codec, the video will come in at a resolution of 480x360, encoded with the superior H.264 codec.

Embedding High Quality Youtube Videos [via Kottke]
View YouTube in high-res

November 4, 2008

Live via hologram

During tonight's election coverage, CNN pulled out some deep tech, displaying Jessica Yellin live via hologram. I looked closely and wasn't even able to see the R2 unit behind the scenes.

<update>
My original impression of how this works is below. A comment from Eric suggests that this might actually be a real hologram that Wolf can see in person, and not a live bluescreening effect. More on this at the end of the post.
</update>

From what I can tell (and I could be wrong), this is done using a combination of technologies, most of which you could simulate at home if you could be satisfied using standard equipment, some careful camera work, and post production techniques instead of the real-time hardware and networked camera equipment CNN is rocking.

The person is recorded inside of a blue or green tent surrounded by an array of cameras that are able to catch several angles at once, presumably with each camera partnered with a real camera on the studio stage. The appropriate holo-camera feed is chosen depending on the real studio camera being used, and the holo camera is networked and synced to move exactly with its partner camera in the studio. This allows the hologram to shift perspective appropriately as the studio camera scoots around the stage. You might compare this to how the virtual first down line is tweaked in real-time to fit the various camera positions in a football game broadcast, except in this case it's not a generated asset, it's a live video feed that's carefully filmed to be at the exact perspective.

Finally, using traditional keying/blue-screen techniques, the tent background color is alphaed out of the feed and the video is overlayed on top of the studio feed, leaving the keyed-out hologram correctly perspective positioned on the final output.

There are two final added touches that make this pretty convincing. One is the red circle on the floor. My best bet is that it's real and created with a red light from above in the live studio feed. The second is the person-to-person conversation. Wolf Blitzer is a pretty good actor - there's no way he's actually seeing the hologram in front of him.

Or can he? Eric points us to the Musion Eyeliner and Cisco Telepresence technology that can display what appears to be a fairly high-fidelity hologram in a stage environment. Here's a video that shows how such a system would be set up:

I remain a bit unconvinced that this is actually what's going on, mostly because of the full 180 degree camera POV that was used in the CNN version, but doesn't seem possible with the Musion system. What are your thoughts? Please post them in the comments.

Anyone care to make their own hologram video with a moving camera? It'd be a bit of a challenge using consumer equipment, and I'm not sure what software you'd use if you didn't have something like After Effects, but it'd be pretty fun to see. For inspiration, here's a decent one done with a fixed camera position:

CNN Hologram Interview [via MAKE]
Real Life R2D2 Hologram

Cisco Telepresence Demo On Live Stage
Musion Eyeliner Hologram Projection System

July 4, 2008

Direct video manipulation interface

Direct manipulation of video is one of the more uncanny HCI concepts I've ever seen. Instead of manipulating time with a traditional scrubber bar, the user can drag objects in the video across their path of movement. Nothing in the video actually changes, but the perception is that you can directly manipulate the objects in the video stream by pulling them around through time.

There's a Windows application called DimP which implements this interface. When you hover over a movable object in the video, a light path appears that emphasizes the object's motion curve, which you can then move the object across. From the DimP website:

So what's being manipulated, exactly? Both the video content (e.g., the things you see moving in the video) and the "tape head". When using DimP, the user directly manipulates the video content and indirectly manipulates the tape head. When using the seeker bar, the user directly manipulates the tape head and indirectly manipulates the video content.

The video above describes how DimP works in a bit more detail, showing a few different video scenarios where direct manipulation really shines. It's intuitive and bizarre at the same time. If the universe is completely deterministic, I can't help but think this is what time travel must look like.

DimP - A Direct Manipulation Video Player
DRAGON - Direct Manipulation Interface Demo for OS X

June 27, 2008

Arduino VGA demo

Sebastian Tomczak has been playing around with controlling VGA output from an Arduino. Using Max/MSP to process audio and send data to the Arduino and a standard VGA output to send sync data to the monitor, he's been able to put together some cool video effects.

In these examples, i am simply using three pins to control the RGB lines. However, the Arduino is not generating horizontal or vertical sync - this is generated by a computer.

You can grab the Max patch and Arduino code from Sebastian's post. I dig the effect - it reminds me of the cool C4 demos kids used to make.

Hacking VGA lines with Arduino

June 20, 2008

Milkscanner - 3D scanning with LEGO and milk

Friedrich Kirschner's Milkscanner is a clever method for scanning 3D objects using only a webcam, some milk, and a camera rig made out of LEGO.

The basic idea is this: you place an object in a container, incrementally fill the container with milk, and take a photo after each tiny fill increment. The Milkscanner software mattes out the white part of the images, resulting in a silhouette "slice" of the object for each increment in the Z dimension. Each slice gives you information about the outer perimeter of the object at that depth (assuming the object is convex).

Milkscanner is able to output a depthmap from this information which you can use in Blender or MovieSandbox, an open source machinima filmmaking tool. Friedrich has been using the latter to produce some pretty fantastic work. Instead of small objects, however, he was able to scan a human using a bathtub which was filled with ink-tinted water.

The original version is written in C# and requires a Windows PC with the latest DirectX. If I read things correctly, there is a new version that will be released soon which is written using a cross platform drawing and image capture API. Hopefully this means that the new release will be available for Linux and OS X. Fingers crossed - this looks like fun.

Fluidscanner
Milkscanner binary and source downloads (distributed with MovieSandbox)

June 19, 2008

Big Buck Bunny: open source animation

Earlier this year, I wrote about project Apricot, an open source game that is currently under development using Blender and the Crystal Space game engine. This isn't the only project that the Blender Institute has been funding recently. Big Buck Bunny, a completely open source animated film, was released at the end of May. It's an impressive case study for what can now be done on the Blender platform.

This Open movie project had as main targets:
Developing tools in Blender for editing and rendering hair, fur or grass
Improve character animation tools for cartoonish motion and deformation
Test Blender with giant outdoor environments, with large grassy fields and many trees with leaves
Further validate Blender as a professional animation creation suite

And secondary:

Create a great and good looking animation short, licensed freely as open content
Provide content for other artists to learn from or to re-use, including documentation and tutorials

And of course: Have lots of fun!

I recognized a few of the film's characters from some of the demos that have been released in the Apricot game development site. The beauty of open source is that a lot of these assets can be shared between projects. There's also something to be said for a development culture that embraces documentation and information sharing. Take this "bunny rig" character animation control demonstration, for example:

The Blender community has already been really good with program documentation, tutorials and howtos. The development of open source games and films, with all the techniques and artwork that is a part of that process, takes things one step further. Now you also have a chance to learn from the techniques that were used in the making of a larger film project, straight from Blender animation gurus. It's not every day you have an opportunity to download full artwork, scene, and animation assets for an entire film.

Big Buck Bunny
Blender - open source 3D content creation suite
Elephants Dream - the first open movie project, made using Blender

Previously: Open source game development

June 9, 2008

Time lapse movies using a graphing caclulator

If you want to shoot time lapse movies with your DSLR, you need an intervalometer, a simple device which sends a signal to your camera to trigger the shutter at a timed interval. You can buy one for around $100, or you can write a few lines of basic and have your trusty TI calculator take timed photos for you, resulting in nifty movies like this:

Yonderknight has an Instructable for doing exactly this with a standard TI 83. You can connect a Canon EOS Rebel to the calculator with the standard 2.5mm data link socket, and the software just sends a 1 down the line once a second. Matt Coneybeare tool this a step further with his code for the TI-89, allowing the user to specify a duration and interval period.

Both howtos walk you through the whole process, including a couple of recommendations for importing and converting the image frames into a video. It should be pretty straightforward to adapt either of these methods to your specific TI platform and video needs.

Turn a TI-83 into an intervalometer
Time-lapse code for the TI-89

June 5, 2008

DIY Slingbox

Using a standard DV cam, a Mac Mini, and the Quicktime Broadcaster utility, you can roll your own Slingbox-style TV streamer on the cheap. David Glover, realizing that his DV camera had an analog input and firewire output, put together a howto for doing just this:

Yesterday from a dusty shelf I discovered my Sony DV camera. And after playing with it for a while I discovered (or possibly re-discovered, as I might have just forgotten) that it has analogue video inputs that it will digitise and then spit out of the DV port.
So this gave me an idea - this is essentially what the Slingbox does, except the Slingbox outputs a network stream rather than DV video. But I have a Mac Mini sitting underneath my TV downstairs, and that has a DV port on it...

This is really handy if you want to catch a show on your computer while you are working from another room. Assuming you also have a DV camera and a spare Mac you can connect to your TV, it's also essentially free.

DIY Slingbox
QuickTime Broadcaster - Apple's free video transcoder and streaming utility

April 28, 2008

Improving astronomical video using VirtualDub

YouTube user kwakhed23 pushed out this video showing before and after imagery of the Moon. In the "before" part of the video, you can see the effects of the atmosphere warping the Moon's image as it passes over the frame. In the "after" video, a temporal noise reduction filter is applied using the open source video tool VirtualDub. It's difficult to tell for sure in the YouTube compressed video, but it appears to have cleaned up the image nicely.

i thought this might be useful to other amateur astronomers who use the "mount the camera on a tripod and point it at the eyepiece" technique. you should be able to get much more detail this way.

I've used VirtualDub for deinterlacing and other random video cleanup projects before, and it's a very handy tool. I'm not certain exactly which filter is being used by kwakhed23, but in addition to the built-ins, you can check out Donald Graft's site for numerous other contributed filters which might be worth playing around with.

Better Astronomical Images Via Filtering
VirtualDub
Donald Graft's Collection of VirtualDub Filters

March 3, 2008

View YouTube in high-res

YouTube has been testing higher bitrate encodings of it videos, which you can see if you add a &fmt=8 or &fmt=16 to the video url. Historically, all videos have been delivered to the lowest common denominator: sorenson encoded 320x240. By adding &fmt=6 to the URL, the video is served up in 448x336 resolution and I'm guessing it's using the VP6 codec (can anyone confirm?). &fmt=18 gives you the iPhone-style MP4 stream.

What videos will actually look better in the higher res format is completely dependent on the material that was uploaded to YouTube, obeying the rules of garbage in garbage out. I've looked at a number of videos where you can't really tell the difference between the low and high-res versions, presumably because the uploaded video was already heavily compressed or pre-scaled to 320x240. There are a few, however, that are strikingly better, such as the skateboarding dog above.

A greasemonkey script is available which will cause Firefox to automatically load the fmt=18 version, if available. A quick install and you can be wasting time at twice the bitrate.

Watch High-Resolution YouTube Videos - [via] Link
YouTube HD Greasmonkey Script - Link

February 17, 2008

360 degree video in Flash

Quentin Lengelé put together a cool demo for a Flash application that uses the Papervision 3D library to pan around a 360 degree video while it's playing:

The idea was to apply the BitmapData of that movie on a GeoSphere.
The GeoSphere is made in 3DSMAX with flipped faces and exported in ASE Format.
The ASE Format is readable by Papervision3D.

Then you just need to draw your bitmapData into a texture you apply to the ASE in ActionScript.

I'd be really interested in seeing a DIY version of the 360 degree camera hardware. Has anyone taken something like this on?

360 Degree Video with PaperVision 3D - [via] Link

January 15, 2008

Unlimited ripping of Netflix "Watch Now" movies

A while ago we wrote about removing the DRM from Netflix "Watch Now" movies. At the time, it involved wading through a bit of HTML source to find the target video URL. Since then, a couple of important things have happened: a Greasemonkey script was written that makes it a bit easier to download and process the DRMed WVM file, and more importantly, Netflix is now allowing unlimited downloads.

What can you do with this? Well, you can download a number of videos ahead of time and then watch them at your leisure, especially if you travel a lot and are offline for extended periods of time. It also means you can convert the files to mp4 format for playing on your mac, iPod or Apple TV device. Or maybe you were hoping to finish that documentary you were making about the strange facial expressions of Sylvester Stallone and needed a few more clips to splice into your film...

How To Rip Netflix "Watch Now" Movies - Link
Netflix Downloader Greasemonkey Script - Link

December 14, 2007

iPhone HD video recorder

The Monster and Friends Design Studio released a beta version of an iPhone camcorder app today. The hack's author, drunknbass, was able to squeeze about 10fps out of the camera when capturing data at a 2 megapixel HD framesize.

The current beta will do this for 5 seconds, but the author alludes to a future version being able to record indefinitely long clips at a higher frame rate. This may only be achievable at the sacrifice of the huge frame size, though. I'd assume that there are some non-trivial data throughput and compression horsepower limitations that would make long recordings at high framerate and high resolution pretty difficult.

I'm hoping the next version is released with source. Hopefully, with a few heads taking a crack at optimizing things, iPhone users will get a slick guerilla video platform out of this.

iPhone Video Recording - [via] Link

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