HDR - The High Dynamic Range Evolution

Why use HDR High Dynamic Range ?

Scenes which have high contrast lighting pose challenges to the technician that is attempting to bring as much information possible to the viewer. In these scenes one would like to bring into view both detail of the shadowed area and the high light area and have them correctly exposed.  While the information may be recreational in nature, it can also be for industrial and scientific applications.  High dynamic range or HDR is already quite common in still photography.  The commonly used technique of bracketing is generally regarded as the well known method.

HDR Video can be achieved in much the same way.  Using a method called time lapse, the  images are stitched together in real time to produce the HDR video.   This approach requires software to be operating as the HDR engine for the output product and a camera fast enough to achieve a frame rate of NTSC.

HDR High Dynamic Range Science

Recent advances in CMOS sensor technology have enabled the development of HDR to be realized at the sensor level.  In this approach the logarithmic curve response is applied at the pixel level ..  The exposure time for each pixel is adjusted to handle the unique lighting conditions at that pixel location in the image sensor array   and the output from the sensor is HDR, high dynamic range video.   The logarithmic response curve dictates the ratio of white pixels to black.  By adjusting the response curve profile, one adjusts the elimination of white or black pixels in the resulting output.

HDR High Dynamic Range Applications

The advantages of HDR are numerous; the most appropriate for industrial applications is the elimination of software overhead.  At the commerical end, HDR brings advantages as an in car camera system. The glaring sun or high beam headlights wreak havoc on traditional car cameras. Furthermore, with a lot of the processing taking place at the hardware level, it introduces a simplification for the user who is less interested in how it works and more interested in the application and implementation of the technology.

Please visit the side bar menu for available hardware and real world solutions that are commercially available with Invisual E.   We would be glad to hear from you if you have a specific HDR application you would like to discuss.