R: Download Image Using Rvest

R: Download image using rvest

Here's one example to download the R logo into the current directory.

library(rvest)
url <- "https://www.r-project.org"
imgsrc <- read_html(url) %>%
  html_node(xpath = '//*/img') %>%
  html_attr('src')
imgsrc
# [1] "/Rlogo.png"

# side-effect!
download.file(paste0(url, imgsrc), destfile = basename(imgsrc))

EDIT

Since authentication is involved, Austin's suggestion of using a session is certainly required. Try this:

library(rvest)
library(httr)
sess <- html_session(url)
imgsrc <- sess %>%
  read_html() %>%
  html_node(xpath = '//*/img') %>%
  html_attr('src')
img <- jump_to(sess, paste0(url, imgsrc))

# side-effect!
writeBin(img$response$content, basename(imgsrc))

Using a list of urls in R, How to web scrape images, download the files and group the images back to original url?

The images are located at different location. You can try the following code -

library(rvest)

lapply(URLs, function(x) {
  x %>% 
    read_html() %>% 
    html_nodes("picture source") %>%
    html_attr("data-srcset") %>% 
    strsplit(',') %>%
    .[[1]] %>%
    na.omit %>%
    trimws %>%
    .[1] -> img
  if(!is.na(img))  download.file(img, paste0('photo', Sys.time(), '.jpeg'))
})

Web scraping of image

You need to specify which attribute you want to extract as a parameter for html_attr. Also, you may want to make your CSS selector, the parameter for html_node, more specific. Here is my code:

library(rvest)

UrlPage <- html ("http://eyeonhousing.org/2012/11/gdp-growth-in-the-third-quarter-improved-but-still-slow/")
ImgNode <- UrlPage %>% html_node("img.wp-image-5984")
link <- html_attr(ImgNode, "src")

The link variable now contains the URL.

You can find a decent reference for css selectors here:
http://www.w3schools.com/cssref/css_selectors.asp

Also the rvest documentation has some good examples on how to use its functions:
http://cran.r-project.org/web/packages/rvest/rvest.pdf

how to download and display an image from an URL in R?

If I try your code it looks like the image is downloaded. However, when opened with windows image viewer it also says it is corrupt.
The reason for this is that you don't have specified the mode in the download.file statement.

Try this:

download.file(y,'y.jpg', mode = 'wb')

For more info about the mode is see ?download.file

This way at least the file that you downloaded is working.

To view the image in R, have a look at

jj <- readJPEG("y.jpg",native=TRUE)
plot(0:1,0:1,type="n",ann=FALSE,axes=FALSE)
rasterImage(jj,0,0,1,1)

or how to read.jpeg in R 2.15
or Displaying images in R in version 3.1.0

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