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Video: Raytrix demonstrates R29 LightField Features

markus — Sun, 19 May 2013 07:00:30 +0000

With their newest Youtube-Upload, German LightField specialist Raytrix demos the LightField features of their R29 camera.

The HD video includes original footage recorded with the high-end camera (resized from 3288 x 2192 = 7.2 megapixels; and 100 % crops), and demonstrates the reconstruction of 3D information – even at a subject-to-lens distance of 400 meters – as well as software refocus and extended depth of field.
Video frame rate for full-resolution imaging is 5 frames per second.

For more information about the R29 LightField Camera and other models, check out our Raytrix camera section, and Raytrix’ official product page.

Lenticular Print Ad shows secret Message to Children

markus — Fri, 17 May 2013 17:00:20 +0000

Lenticular prints are commonly used to create an illusion of movement or the impression of spatial depth, by selectively showing different images when seen from different angles. In the case of lenticular print postcards, posters etc., the distance between our eyes is enough to show a slightly different image to each eye, creating an illusion of depth.

Spain’s ANAR Foundation (Aid to Children and Adolescents at Risk) operates an anonymous and confidential help line for abused children. With their most recent poster campaign, they solved the problem of potentially abusive parents keeping their children from even looking at the ad that is set to help minors at risk.
The innovative lenticular print posters are designed two show two different images, depending on the beholder’s height: a general awareness/warning message to adults, and a secret message and phone number to children under the age of 10.

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NOAA Looking to Dive into Light Field Imaging of Fish

markus — Tue, 14 May 2013 21:00:07 +0000

LightField technology has a wide potential field of applications, which we’ve only recently begun to explore. One of these applications, which may soon be realized, is the 3D imaging of fish for scientific use:
The US National Oceanic and Atmospheric Administration (NOAA) has recently filed a statement of need notice for the development of an “underwater LightField camera system for single camera 3D imaging of fish” (WRAD-13-02577).
Looking at the specific camera requirements, it’s clear that the NOAA have a clear idea of what they want. At this stage, however, there’s no information about the precise application of the LightField pictures and video that the agency is hoping to record.

Details of the statement:

PURPOSE:
This equipment will be used to develop an underwater light field (plenoptic) camera system for single camera 3-dimensional imaging of fish. This equipment fulfills requirements specified in the fully funded ASTWG proposal.

TECHNICAL SPECIFICATIONS:
This light field camera must to have industrial control via Giga Ethernet, be delivered with interfacing control software, a software development kit (SDK), and a high speed processing machine for image analysis and post processing/refocusing.

The camera itself needs to have the following specifications:

Industrial control capabilities for remote operation.

Frame rate: 25fps minimum

Light Field resolution: 4.2 Megarays

Micro Lens Diameter resolution: 23 pixel/micro lens.

Resolution: 2048 x 2048

3-D Resolution: Up to 200 discrete depth layers.

35mm lens with f/2.4 optics

The processing machine

Software development Kit (SDK) / Application programming interface (API) for MS windows.

High speed Graphical Processing unit. Graphics card must support NVIDIA CUDA with computing capability 1.0 or higher

DELIVERABLE SCHEDULE:
4 weeks after receiving order

Specific business information from interested potential contractors, including business details and proof of know-how, can be submitted until May 20, 2013.

Update: As reader Craig Kolb pointed out, the specs are tailored to the Raytrix R5 Plenoptic Camera.

Refocus: New App brings Software Refocus to Windows Phone 8

markus — Thu, 09 May 2013 16:00:19 +0000

The iPhone World has recently gained a cool new category of apps that bring refocus capabilities to your smartphone: tap2focus and FocusTwist, both released within a small timeframe, use the iPhone’s standard camera to take several pictures at different focus levels, and combine the individual frames into an interactive touch-to-refocus picture à la Lytro.

Now, Windows Phone 8 is the second platform to gain software refocus picture taking: The app, simply named Refocus (0.99 $) uses the same “image series” technique to record the necessary data, but unlike FocusTwist it’s not limited to square pictures
There’s a free trial version which you can use to test whether your phone supports manual focus (required for the app to work).

Refocus allows you to capture the full depth of a moment. Take a picture and change the point of focus at any time later.

Warning: Not all phones support manual focusing. Please use the trial version to check if it works on yours! Otherwise you can only use it to view images.

Features:
- Take refocusable images
- Refocus images manually or using tap to focus
- Share your favorite views on Facebook, Twitter or via E-Mail or Bluetooth
- Upload complete images to SkyDrive
- Open RFI-Files you find on the Web or receive via E-Mail
- View your images on a Live Tile

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Compressive LightField Photography enables Higher Resolution LightFields in a Single Image

markus — Mon, 06 May 2013 21:10:40 +0000

Today’s LightField technology uses either of two methods to record a LightField: it either reconstructs a single low-resolution LightField image (e.g. using microlens arrays or coded masks), or requires several individual pictures to be taken and combined for a high-resolution LightField (e.g. using camera gantries or coded apertures).
In a recent publication, Kshitij Marwah and colleagues introduced a new LightField camera prototype that combines the advantages of these two methods, to reconstruct higher-resolution LightFields from a single, coded image. To do so, they have co-designed the prototype camera to incorporate both of the main aspects of LightField technology: camera optics and computational processing.

The team introduced (1) a new way to represent the high-dimensional signals of LightFields, called LightField Atoms (“the fundamental building blocks of natural light fields”), (2) non-linear sparse coding techniques for improved reconstruction, and (3) optimized, optically coded 2D LightField projection.

Advantages of this new system include increased LightField resolution as well as better compression and noise reduction. However, it comes with disadvantages, such as reduced light transmission (due to the coded mask), more required processing power/time, and the need for LightField Atom Learning from multiple test setups.

More information: Marwah K., Wetzstein G., Bando Y. & Raskar R. (2013): Compressive Light Field Photography Using Overcomplete Dictionaries And Optimized Projections, Technical Paper, ACM Siggraph 2013