söndag 25 maj 2008

Remove motion blur from videos

When you take move the camera while taking a photo you get motion blur. At this years Siggraph conference there are several papers about how to remove motion blur from images. Take a look at this paper High-quality Motion Deblurring from a Single Image that uses a single blurry image as source and makes a virtually perfect photo. The screenshots are quite amazing. As people from Abobe are part of the paper we can hopefully sees this as a filter in future versions of photoshop.

Using this teqnique together with a video frame capture software like fast video indexer could create really awsome screenshots from videos.

The abstract for the paper:
"We present a new algorithm for removing motion blur from a single image. Our method computes a deblurred image using a unified probabilistic model of both blur kernel estimation and unblurred image restoration. We present an analysis of the causes of common artifacts found in current deblurring methods, and then introduce several novel terms within this probabilistic model that are inspired by our analysis. These terms include a model of the spatial randomness of noise in the blurred image, as well a new local smoothness prior that reduces ringing artifacts by constraining contrast in the unblurred image wherever the blurred image exhibits low contrast. Finally, we describe an efficient optimization scheme that alternates between blur kernel estimation and unblurred image restoration until convergence. As a result of these steps, we are able to produce high quality deblurred results in low computation time. We are even able to produce results of comparable quality to techniques that require additional input images beyond a single blurry photograph, and to methods that require additional hardware."

Self animated images

Video - A series of framed images put together, one after another, to simulate motion.

Did you know you can get away with only one image and let the brain to the work of animating the image. If you make an image in the right way your brain will fool you into animating the image yourself in you head.

Siggraph is THE yearly conference on computer graphics. This year, as usual, there are a lot of interesting papers that to be presented and some of them are already beginning to leak out.

The image will look much better in fullscreen
The effect is much better if you click the image and view it as large as possible

As I develop a video software that takes videos and generates images from it a paper about Self-Animating Images got my attention. In Self-Animating Images: Illusory Motion Using Repeated Asymmetric Patterns scientists, Ming-Te Chi and Tong-Yee Lee and Yingge Qu and Tien-Tsin Wong, propose a computational method to generate self-animating images.

Even if you are normally not interested in scientific papers take a look at the pictures in it anyway. On the project page there is also a link to a pdf with more example images. Read the instructions on the page for how to best view the images.

Here is the summary from the project page:
"Illusory motion in a still image is a fascinating research topic in the study of human motion perception. Physiologists and psychologists attempted to understand this phenomenon by constructing simple, color repeated asymmetric patterns (RAP) and found several useful rules to enhance the strength of illusory motion. Based on their knowledge, we propose a computational method to generate self-animating images. First, we present an optimized RAP placement on streamlines to generate illusory motion for a given static vector field. Next, a general coloring scheme for RAP is proposed to render streamlines. Furthermore, to enhance the strength of illusion and respect the shape of the region, a smooth vector field with opposite directional flow is automatically generated given an input image. Examples generated by our method are shown to evidence the illusory effect, and the potential applications for entertainment and design purposes."

fredag 2 maj 2008

Flash is now open source

Adobe finally on the 1st of May announced that they will turn Flash and some related technologies into open source. The new open source initiative goes under the name of open screen is backed by a number of really large media and hardware companies like:
ARM, Chunghwa Telecom, Cisco, Intel, LG Electronics Inc., Marvell, Motorola, Nokia, NTT DoCoMo, Qualcomm, Samsung Electronics Co., Sony Ericsson, Toshiba and Verizon Wireless, BBC, MTV Networks, and NBC Universal.

The goal of the new open source project is to:
• Remove restrictions on use of the SWF and FLV/F4V specifications
• Publish the device porting layer APIs for Adobe Flash Player
• Publish the Adobe Flash® Cast™ protocol and the AMF protocol for robust data services
• Remove licensing fees – making next major releases of Adobe Flash Player and Adobe AIR for devices free

What this probably means is that Flash content is going to be more common in handheld devices and perhaps even in TV boxes. Wide adoption of Interactive TV is one step closer.

More specific what has been done today is that:
• The SWF file format specification is published and there is no longer a license requirement to support the Flash media format. This makes it possible to write software that support Flash on any devices without paying royalty to Adobe. You can download the Flash specification today from here
• The FLV/F4v specification is published and you can download it from here. FLV/F4V is the standard in Flash that supports Video and Audio. FLV and F4V are the de facto standard for web video today; over 75% of broadcasters who stream video on the web use these formats.

If you are a developer you can find out more about Open Screen at Adobes development page.

It is a probably a safe bet that the open screen announcement comes as a result of Microsofts huge success with its new Silverlight platform. Silverlight offers about the same functionality as Flash but with support of Microsofts mature Visual Studio tools and the .net language.

Flash as a open format can only mean good things for the future of interactive video and is really interesting in the light of W3Cs work on a video extension for the html standard.