meanhsv: Compute mean HSV and RGB of image/object

In SolomonMg/ImageMetrics: Facilitates image analysis for social scientists.

Description

meanrgb returns the mean RGB values for the imageMatrix object. meanHSV returns the mean HSV values for the imageMatrix object.

Usage

meanrgb(imageMatrix)
meanhsv(imageMatrix)

Arguments

imageMatrix

an imageMatrix object

Value

A list with three elements corresponding to the HSV or RGB measures in the imageMatrix.

Author(s)

Solomon Messing <[last-name] at stanford dot edu>

Examples

## Compare brightness of video still capture from MSNBC footage of Obama, with still capture from 
## an ad featuring the same footage (only Obama appears darker) that appeared in an ad on the Clinton 
## campaign website, causing a stir in the blogosphere.

data(Campaign2008)
 
clinton = new("imageMatrix", X = readPNG(system.file("extdata", "Clinton.png", package="ImageMetrics")), type = "rgba")
clintonface = new("imageMatrix", X = ObjSelect( image = clinton@X, poly= clintonpoly ), type = "rgb")

msnbc = new("imageMatrix", X = readPNG(system.file("extdata", "MSNBC.png", package="ImageMetrics")), type = "rgba")
msnbcface = new("imageMatrix", X = ObjSelect( image = msnbc@X, poly= msnbcpoly ), type = "rgb")

## Not run: 
plot(clinton)
plot(clintonface)
plot(msnbc)
plot(msnbcface)

## End(Not run)

meanhsv(clintonface)
meanhsv(msnbcface)

SolomonMg/ImageMetrics documentation built on May 27, 2019, 7:39 a.m.