ImageStat
Module¶
The ImageStat
module calculates global statistics for an image, or
for a region of an image.
-
class
PIL.ImageStat.
Stat
(image_or_list, mask=None)¶ Calculate statistics for the given image. If a mask is included, only the regions covered by that mask are included in the statistics. You can also pass in a previously calculated histogram.
- 参数
image – A PIL image, or a precalculated histogram.
mask – An optional mask.
-
extrema
¶ Min/max values for each band in the image.
注解
This relies on the
histogram()
method, and simply returns the low and high bins used. This is correct for images with 8 bits per channel, but fails for other modes such asI
orF
. Instead, usegetextrema()
to return per-band extrema for the image. This is more correct and efficient because, for non-8-bit modes, the histogram method usesgetextrema()
to determine the bins used.
-
count
¶ Total number of pixels for each band in the image.
-
sum
¶ Sum of all pixels for each band in the image.
-
sum2
¶ Squared sum of all pixels for each band in the image.
-
mean
¶ Average (arithmetic mean) pixel level for each band in the image.
-
median
¶ Median pixel level for each band in the image.
-
rms
¶ RMS (root-mean-square) for each band in the image.
-
var
¶ Variance for each band in the image.
-
stddev
¶ Standard deviation for each band in the image.