Collections-OCR/ocrMangle.R

63 lines
1.8 KiB
R

# A script to OCR/parse/mangle Collections label-images
# Note - this takes ~2 seconds per label-image
# (c) 2019 The Field Museum - MIT License (https://opensource.org/licenses/MIT)
# https://github.com/fieldmuseum/Collections-OCR
library(tidyr)
library(magick)
library(stringr)
library(tesseract)
# download relevant languages/training data
tesseract_download("lat") # Latin
tesseract_download("deu") # German
# get list of JPG & JPEG image files
imagelist <- list.files(path = "images/", pattern = ".jp|.JP")
# setup table for OCRed text
imagesOCR <- data.frame("image" = rep("", NROW(imagelist)),
"line_count" = rep("", NROW(imagelist)),
"text" = rep("", NROW(imagelist)),
stringsAsFactors = F)
imagesOCR$line_count <- as.integer(imagesOCR$line_count)
# loop through each label-image
for (i in 1:NROW(imagelist)) {
# OCR the image to text
ocrText <- image_read(paste0("images/", imagelist[i])) %>%
image_ocr(language = c("eng", "lat", "deu"))
imagesOCR$text[i] <- ocrText
# include filename & count of lines in row
imagesOCR$image[i] <- imagelist[i]
imagesOCR$line_count[i] <- str_count(ocrText, "\n+")
# show progress
print(paste(i, " - ", Sys.time()))
}
# split text lines to separate columns
ocrText <- separate(imagesOCR, text,
into = paste0("Line",
seq(1:max(imagesOCR$line_count, na.rm = T))),
# into = seq(1:20), # if need consistent NCOL
sep = "(\n)+",
extra = "merge", fill = "right")
# export CSV
write.csv(ocrText,
paste0("ocrText-",
gsub("\\s+|:", "", Sys.time()),
".csv"),
na = "",
row.names = F)