IMcHistogram2SamplingCoverage Property

Property Value

Type: Double

This property is 100 by default, in which case no sampling is ever done. If the value is less than 100, but greater than zero, then some pixels may be skipped when computing the histogram. The relationship between the SamplingCoverage property value and the number of pixels skipped is not linear, as it depends on the total number of pixels that would be needed for full coverage and how many frames need to be examined. For small image/Aoi areas with a single frame, all pixels will be included in the histogram even when the SamplingCoverage value is low. For very large image/Aoi areas in many frames, the fraction of pixels sampled will approximate the square of the SamplingCoverage value treated as a percentage (e.g., 50 => 0.5*0.5 = 1/4 of all pixels will be sampled). The SampledFraction property will be a value between 0 and 1.0 which gives this result for the current histogram. If the mchmFavorSkippedFramesWhenSampling Mode bit is set and the source image has a large number of frames, sampling will try to skip as many as possible while still getting a good estimate of the histogram. Clearly this will be most appropriate when the image changes slowly from one frame to the next.