In the development of motion imaging systems beyond 1080p HD, various proponents have proposed (and in some cases deployed) three schemes alleged to improve quality: (i) bit depths beyond the 10-bit colour components standard for studio HD, (ii) pixel counts (“4 K” and “8 K”) higher than the 1920x1080 of HD, and (iii) frame rates higher than 60 Hz. However, the tradeoffs among these various options are not well understood; it is not immediately clear into which of these three arenas additional bits should be placed in order to achieve maximum improvement in perceptual quality. Also, traditional image quality criteria for moving images have mainly been carried over from still imaging; few criteria are available to assess motion portrayal. Finally, motion portrayal is often described by terms such as “strobing” that have no consistent definition.
In this 6-hour course, we address the fundamental physics constraints of motion image cameras and displays, and we reach into psychophysics to understand how the visual system interacts with the physics. We describe the properties of vision that relate to the choice of bit depth, and their dependence upon visual adaptation and absolute luminance (of the display and the viewing environment). The fundamental concept of eye tracking by the viewer is described. The key concept that links physics to vision in motion imaging is the optic-flow axis; that concept clarifies the mechanisms that cause loss of resolution in the presence of motion. Such losses are characterized by dynamic resolution.
At the completion of the course, attendees will have a complete understanding of the drawbacks of today's imaging systems, but, more importantly, will have knowledge and information that allows informed decisions to be made about key parameters of future systems such as bit depth, pixel count, and frame rate.Upon completing the course, attendees will:
- Understand the advantages of spatial oversampling in real sensors and displays
- Understand the principles of eye tracking in motion image portrayal
- Understand why dynamic resolution is an important metric for moving image analysis
- Correctly define and distinguish flicker, judder and strobing
- Understand the optic flow axis and its key role in imaging
- Understand how frame-repeat or multiple flashing damages resolution
- Be aware of the effects that impair resolution in the presence of motion in sensors, processes and displays
- Be able to determine the optimum frame rate for a given moving image portrayal system