convert jpg to greyscale csv using R

Question

I have a folder of JPG images that I\'m trying to classify for a kaggle competition. I have seen some code in Python that I think will accomplish this on the forums, but was

Answer 1

There are some formulas for how to do this at this link. The raster package is one approach. THis basically converts the RGB bands to one black and white band (it makes it smaller in size, which I am guessing what you want.)

library(raster)
color.image <- brick("yourjpg.jpg")

# Luminosity method for converting to greyscale
# Find more here http://www.johndcook.com/blog/2009/08/24/algorithms-convert-color-grayscale/
color.values <- getValues(color.image)
bw.values <- color.values[,1]*0.21 + color.values[,1]*0.72 + color.values[,1]*0.07

I think the EBImage package can also help for this problem (not on CRAN, install it through source:

source("http://bioconductor.org/biocLite.R")
biocLite("EBImage")
library(EBImage)

color.image <- readImage("yourjpg.jpg")
bw.image <- channel(color.image,"gray")
writeImage(bw.image,file="bw.png")