ImageMeasurements¶

ImageMeasurements[image, property] gives a named measurement of an image. The statistics are taken over the samples, with the sample (n − 1) divisor for the deviation:

$ wo 'ImageMeasurements[Image[{{0., 1.}, {0.5, 0.25}}], "Mean"]'
0.4375

A colour image is measured channel by channel:

$ wo 'ImageMeasurements[Image[{{{1., 0., 0.}, {0., 1., 0.}}}], "Mean"]'
{0.5, 0.5, 0.}

Entropy and Energy are taken over the histogram of distinct pixels, so a colour pixel counts once however many channels it carries — two distinct pixels give Log[2]:

$ wo 'ImageMeasurements[Image[{{{1., 0., 0.}, {0., 1., 0.}}}], "Entropy"]'
0.6931471805599453

A list of names gives a list of measurements, and "Properties" names the ones it knows:

$ wo 'ImageMeasurements[Image[{{0., 1.}, {0.5, 0.25}}], {"Mean", "Total"}]'
{0.4375, 1.75}

$ wo 'Take[ImageMeasurements[Image[{{0., 1.}}], "Properties"], 3]'
{AspectRatio, Channels, ColorSpace}