R/draft.R

In VincentGuyader/crocodile: Cut, Slice and Arrange an Image

#' safe_crop <- purrr::possibly(magick::image_crop,otherwise = NULL)
#' #' Slice an image and reorder it
#' #'
#' #' @param img magick image object returned by image_read() or image_graph()
#' #' @param dpi number of slice
#' #'
#' #' @export
#' #' @import purrr
#' #' @import magick
#' #' @import glue
#' #' @examples
#' #' library(magick)
#' #' image_read("http://fr.web.img6.acsta.net/pictures/15/07/20/18/14/582462.jpg") %>%
#' #' slice_and_mix(dpi = 50)
#' slice_and_mix <- function(img,dpi=40){
#'   orig <- image_info(img)
#'   c(0,seq_len(dpi)) %>%
#'     map(
#'       ~img %>% safe_crop(geometry = glue::glue("{orig$width/dpi}x{orig$height}+{.x*orig$width/dpi}+0"))
#'     ) %>%
#'     compact()-> d1
#'
#'   b1 <- d1[c(TRUE,FALSE)] %>%
#'     reduce(c) %>%
#'     image_append(stack = FALSE)
#'   b2 <- d1[c(FALSE,TRUE)] %>%
#'     reduce(c) %>%
#'     image_append(stack = FALSE)
#'   image_append(c(b1,b2),stack = FALSE)
#' }
#'
#' #' Slice an image and reorder it twice
#' #'
#' #' @param img magick image object returned by image_read() or image_graph()
#' #' @param dpi number of slice
#' #'
#' #' @export
#' #'
#' #' @examples
#' #' library(magick)
#' #' image_read("http://fr.web.img6.acsta.net/pictures/15/07/20/18/14/582462.jpg") %>%
#' #' lens(dpi = 50)
#' lens <- function(img,dpi=30){
#'   img %>%
#'   slice_and_mix(dpi = dpi) %>%
#'   image_rotate(degrees = 90)%>%
#'   slice_and_mix(dpi = dpi) %>%
#'   image_rotate(degrees = -90)
#' }
#'
#'