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Archive: Video

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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

September 26, 2007

Turn a Symbian Series 60 phone into a webcam

Smartcam is an open source utility that will turn a bluetooth-enabled Symbian Series 60 camera phone into a webcam that you can use on your Windows PC. Half of the application runs on the phone, reads from the camera and sends video frames to the PC via bluetooth. The other half of the application runs in Windows, receives the video frames and creates a virtual web camera that can be used in programs like Skype or Yahoo messenger.

There's not much documentation, and the project is still alpha, but if you can grep the source, you technically have everything you need to make other applications which pull live video from the phone.

SmartCam project page on SourceForge - [via] Link

September 3, 2007

VGA over Cat-5 ethernet

If you've ever needed to place a VGA monitor further than the standard 6 foot cable allows, you may be familiar with some of these problems:

VGA cables are expensive
Several cables chained together affects signal quality
Running a VGA cable through conduit is pretty difficult

You can avoid a lot of these problems by making a couple VGA to Cat-5 adapters. This will let you run standard, cheap, easy-to-pull ethernet cable between your computer and video display. The twisted pair helps reduce signal loss, though it doesn't work quite as well as the long-run shielded VGA cables. Unless you need to extend your display to over 50 feet, this might be a much easier and more cost-effective way to do things.

VGA over Cat-5 ethernet cable - Link

August 20, 2007

HOWTO - iPod and PSP movies on Windows Mobile

Last week I mentioned that you can use TCPMP on Windows Mobile Smartphones and Pocket PCs to view H.264 encoded MP4s. I glossed over a few details, so here's a quick guide for getting everything running.

What You Need:

TCPMP: download the latest version for Pocket PC or Smartphone (currently 0.72RC1)- Link
H.264 ffmpeg plugin: under "additional plugins" - Link
AAC plugin: grab the Windows Mobile download under the "BetaPlayer AAC plugin" heading - Link

You'll also need your Smartphone or Pocket PC, a PC with ActiveSync, and enough space on the device (or SDCard) for storing the video you want to watch.

Install the Files:
The TCPMP download is a CAB file. You can either drop this on an SDCard in the device or copy it to the device with ActiveSync. Once it's there, use the file explorer on the device to find the CAB and execute it to begin the install.

After you've installed TCPMP, you'll need to also install the H.264 and AAC codecs so that you can view and hear videos encoded for the iPod. Both of these plugins are downloaded as a ZIP file. Inside you'll find EXE and CAB installers for the Smartphone and Pocket PC Windows Mobile platforms. You can install the CAB files just like you did with TCPMP, or you can execute the EXE installer on your synced PC and ActiveSync will take care of moving it to the device for you.

Transfer and Play Videos on the Device
The fastest way to get large video files to your device is just to drop them on a large SD or MiniSD card and insert it into your device. I did this with a few MP4s I had lying around from MAKE podcasts and Google Video downloads.

You'll find the TCPMP/Core icon in your Start Menu. After executing, you can choose "File->Open" to browse and select an MP4 file to play. There are some settings under options to adjust the video buffer and playback settings. You'll have to experiment to see what works best for your device.

On my test Smartphone, the MP4 video playback is pretty poor, but it does work. The audio doesn't skip, but there are a bunch of dropped video frames during playback. From what I can tell, the device just doesn't have the CPU muscle to decode the video fast enough without hardware acceleration. I have a feeling the Pocket PC hardware might be more up to the task. Please leave a comment if you can confirm this.

August 17, 2007

YouTube and iPod video content on Windows Mobile

Out of the box, Windows Mobile devices can only play WMV files. Formats like Flash video or Quicktime are not supported. Using the open source media player TCPMP and some Pocket IE tweaks, however, you can view the FLV video content available on several popular video sites like YouTube and Google Video, right on your WM5 or WM6 Pocket PC or Smartphone.

For all you Tube-aholics, this is it! You now have direct, unfettered access to Youtube, Google Video & Veoh, in all their glory. Install the CABs listed below, go directly to these websites, and click on a video to play. That's it :)

Even better, you can also use TCPMP to watch H.264 MP4 / iPod encoded videos. With a large enough SD card, you should be able to use the same MP4 encoded videos on your Treo that you play from iTunes or on your iPod or iPhone.

Correction:
dankirkpatrick comments that the device referenced in the MP4-to-Treo article at jaydryden.net is actually a PalmOS device, and not the lookalike Windows Mobile Treo 700w. TCPMP is available for Windows Mobile, though, so I'll try and put together some instructions for this and verify that it works (it should). The encoding info on the Palm article should still apply, you just need to install TCPMP for WM, not for PalmOS.

Full Youtube and Google Video access - Link
Watching MP4 video on ~~Windows Mobile~~ PalmOS using TCPMP - Link
Wikipedia entry on TCPMP - Link