True High Dynamic Range (HDR) video is here. Several years of research at Contrast Optical Design & Engineering have resulted in a working, commercially viable, HDR video system and the publication of a technical paper in the very prestigious SIGGRAPH 2011 conference.
What is HDRI ?
High Dynamic Range Imaging (HDRI) is a technique that photographers can use to extend the range of light intensity, or dynamic range, that can be captured in a single photograph. The camera is placed on a tripod, and a series of photographs (typically three of them) are snapped in quick succession. Each photograph is taken using a different exposure setting on the camera, providing a dark, medium, and bright picture of the scene. These three images are then combined in software to produce a single HDRI photograph.
The Problem with HDRI
One key problem exists with the current state- of- the- art in HDR images: nothing in the scene can move. Since the photos are taken sequentially, any movement causes the combined HDR image to be blurry.
The AMP™ Camera Solution
Contrast Optical’s AMP camera technology solves this key problem by capturing truly simultaneous, pixel- forpixel identical images. AMP is the first camera to use commercially- viable technology to deliver real- time, high dynamic range, high- definition imaging.
Contrast’s in- house developed AMP camera technology uses specialized optics to split the light from a single camera lens onto three camera sensors simultaneously. Image- splitting is performed optically, at the speed of light, guaranteeing perfect motion registration between images. A new image- combining algorithm was developed specifically for this AMP camera system to transform the data from the three camera sensors into a true HDR video stream in real time. Contrast, being a custom optical design firm, approached the problem from a purely optical standpoint, avoiding electronic tricks such as alternating exposure frames (bright/dark) or double- mosaic pixel arrays (red/green/blue and light/medium/dark). Their background in high- end optical system design gave them a unique perspective from which to solve this problem, and the results look impressive.
A fun video that introduces the AMP Camera Technology and gives a sneak preview of the GEN II camera features. AMP captures three images with the exact same exposure time, at the exact same moment in time. A custom blending algorithm is used to combine the images to produce a true HDR image for each frame in the video. Of course, we can’t display true HDR images (yet) so tonemapping is left to the user. For this video, we chose a wide variety of commercially-available tonemappers, just to get the idea across that all the HDR data really is there for every frame. AMP is a trademark of Contrast Optical Design & Engineering, Inc.
For more on tonemapping see our video “AMP Melting Snow”.
