Hi-res still and video capture in single snap
A way of capturing high-resolution still and motion video images simultaneously using the same basic image sensor for both formats, has been developed by researchers looking for better ways to study the human heart.
The team – funded by Biotechnology & Biological Sciences Research Council and the British Heart Foundation at the University of Oxford – combined technologies existing in standard digital cameras and projectors.
The ‘Real Motion Picture’ (RMP) is a pixel multiplexing technique that divides all the camera sensor’s pixels into specific groups that then form part of a ‘bigger picture’ in controlled succession, and during the time needed to take a single standard still image. Using 16-pixel patterns, for example, each pixel is exposed sequentially for 1/16 of the time the main camera shutter stays open, capturing 16 different time points at evenly distributed parts of the image will be captured by the respective pixel groups. Then all 16 groups can be viewed combined as a high-resolution still image, or the sixteen sub-images can be played in sequence to generate a high-speed video clip. As it uses the same basic data, the combined images occupy the same amount of memory.
“The camera’s pixels act as if they were part of tens – even hundreds – of individual cameras taking pictures in rapid succession during a single normal exposure,” explains heart scientist and optical mapping specialist Dr Gil Bub, who is credited with having thought of the RMP concept. “The pattern of pixel exposures keeps the high-resolution content of the overall image, which can then be used as-is, to form a [conventional] high-resolution picture, or decoded into a movie.”
The research team, led by Dr Peter Kohl, had previously created animated models of the heart, which combed multiple types of information about the organ’s structure and function using advanced optical imaging tools, but found conventional imaging methods did not meet their requirements. “In science we may miss vital information like very rapid changes in intensity of light from fluorescent molecules that tell us about what is happening inside a cell,” says Dr Kohl. “Having a massive 12 megapixel sensor, as many cameras now do, does nothing to improve this.”
Kohl claims that the RMP technique could be developed for applications such as CCTV and sports photography. The technology has been patented by Isis Innovation, the University of Oxford’s technology transfer office.