Read EPUB text and metadata.
The epubr package provides functions supporting the
reading and parsing of internal e-book content from EPUB files. E-book
metadata and text content are parsed separately and joined together in a
tidy, nested tibble data frame.
E-book formatting is not completely standardized across all literature. It can be challenging to curate parsed e-book content across an arbitrary collection of e-books perfectly and in completely general form, to yield a singular, consistently formatted output. Many EPUB files do not even contain all the same pieces of information in their respective metadata.
EPUB file parsing functionality in this package is intended for
relatively general application to arbitrary EPUB e-books. However,
poorly formatted e-books or e-books with highly uncommon formatting may
not work with this package. There may even be cases where an EPUB file
has DRM or some other property that makes it impossible to read with
epubr.
Text is read ‘as is’ for the most part. The only nominal changes are
minor substitutions, for example curly quotes changed to straight
quotes. Substantive changes are expected to be performed subsequently by
the user as part of their text analysis. Additional text cleaning can be
performed at the user’s discretion, such as with functions from packages
like tm or qdap.
Install epubr from CRAN with:
install.packages("epubr")Install the development version from GitHub with:
# install.packages("remotes")
remotes::install_github("ropensci/epubr")Bram Stoker’s Dracula novel sourced from Project Gutenberg is a good
example of an EPUB file with unfortunate formatting. The first thing
that stands out is the naming convention using item
followed by some ordered digits does not differentiate sections like the
book preamble from the chapters. The numbering also starts in a weird
place. But it is actually worse than this. Notice that sections are not
broken into chapters; they can begin and end in the middle of
chapters!
These annoyances aside, the metadata and contents can still be read into a convenient table. Text mining analyses can still be performed on the overall book, if not so easily on individual chapters. See the package vignette for examples on how to further improve the structure of an e-book with formatting like this.
file <- system.file("dracula.epub", package = "epubr")
(x <- epub(file))
#> # A tibble: 1 × 9
#> rights identifier creator title language subject date source data
#> <chr> <chr> <chr> <chr> <chr> <chr> <chr> <chr> <list>
#> 1 Public domain… http://ww… Bram S… Drac… en Horror… 1995… http:… <tibble>
x$data[[1]]
#> # A tibble: 15 × 4
#> section text nword nchar
#> <chr> <chr> <int> <int>
#> 1 item6 "The Project Gutenberg EBook of Dracula, by Br… 11446 60972
#> 2 item7 "But I am not in heart to describe beauty, for… 13879 71798
#> 3 item8 "\" 'Lucy, you are an honest-hearted girl, I k… 12474 65522
#> 4 item9 "CHAPTER VIIIMINA MURRAY'S JOURNAL\nSame day, … 12177 62724
#> 5 item10 "CHAPTER X\nLetter, Dr. Seward to Hon. Arthur … 12806 66678
#> 6 item11 "Once again we went through that ghastly opera… 12103 62949
#> 7 item12 "CHAPTER XIVMINA HARKER'S JOURNAL\n23 Septembe… 12214 62234
#> 8 item13 "CHAPTER XVIDR. SEWARD'S DIARY-continued\nIT w… 13990 72903
#> 9 item14 "\"Thus when we find the habitation of this ma… 13356 69779
#> 10 item15 "\"I see,\" I said. \"You want big things that… 12866 66921
#> 11 item16 "CHAPTER XXIIIDR. SEWARD'S DIARY\n3 October.-T… 11928 61550
#> 12 item17 "CHAPTER XXVDR. SEWARD'S DIARY\n11 October, Ev… 13119 68564
#> 13 item18 " \nLater.-Dr. Van Helsing has returned. He ha… 8435 43464
#> 14 item19 "End of the Project Gutenberg EBook of Dracula… 2665 18541
#> 15 coverpage-wrapper "" 0 0tesseract by @jeroen for more direct control of the OCR process.
pdftools for extracting metadata and text from PDF files (therefore more specific to PDF, and without a Java dependency)
tabulizer by @leeper and @tpaskhalis, Bindings for Tabula PDF Table Extractor Library, to extract tables, therefore not text, from PDF files.
rtika by @goodmansasha for more general text parsing.
gutenbergr by @dgrtwo for searching and downloading public domain texts from Project Gutenberg.
Please note that the epubr project is released with a Contributor
Code of Conduct. By contributing to this project, you agree to abide
by its terms.
