SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
This section describes how the dynamic parameter, iridix strength, is calculated.
Dynamic range of a digital camera can be described as the ratio of maximum light intensity measurable (at pixel saturation), to minimum light intensity measurable (but above read-out noise). This is a very important concept to consider when computing iridix strength, because the gain applied by iridix is also proportional to the visible boost of noise in the image. The maximum gain applied by iridix should be determined by the dynamic range of the camera system. This is governed by the equation presented in this section.
With iridix strength is zero, all tone curves are linear for all images. As iridix strength is increased, the variation between curves in shadows, mid tones and highlights increases, resulting in increasing compression of global dynamic range.
Iridix strength is calculated as follows:
Where:
f(analog gain) should only be used when the ISP is in linear mode. Otherwise, it should be set to 1