Update FAQ

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NoDRM 2022-01-11 12:02:44 +01:00
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FAQs.md
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@ -167,12 +167,12 @@ That question cannot be answered for sure. While it is easy to check if a book h
Most Amazon Kindle ebooks are Mobipocket format ebooks, or the new KF8 format. However, some are in a format known as Topaz. The Topaz format is only used by Amazon. A Topaz ebook is a collections of glyphs and their positions on each page tagged with some additional information from that page including OCRed text (Optical Character Recognition generated Text) to allow searching, and some additional layout information. Each page of a Topaz ebook is effectively a description of an image of that page. To convert a Topaz ebook to another format is not easy as there is not a one-to-one mapping between glyphs and characters/fonts. To account for this, two different formats are generated by the DRM removal software. The first is an html description built from the OCRtext and images stored in the Topaz file (HTMLZ). This format is easily reflowed but may suffer from typical OCRtext errors including typos, garbled text, missing italics, missing bolds, etc. The second format uses the glyph and position information to create an accurate scalable vector graphics (SVG) image of each page of the book that can be viewed in web browsers that support svg images (Safari, Firefox 4 or later, etc). Additional conversion software can be used to convert these SVG images to an image only PDF file. The DeDRM calibre plugin only imports the HTMLZ versions of the Topaz ebook. The html version can be manually cleaned up and spell checked and then converted using Sigil/calibre to epubs, mobi ebooks, and etc.
## Are the tools open source? How can I be sure they are safe and not a trojan horse?
All the DRM removal tools hosted here are almost entirely scripts of one kind or another: Python, Applescript or Windows Batch files. So they are inherently open source, and open to inspection by everyone who downloads them.
All the DRM removal tools hosted here are almost entirely written in Python. So they are inherently open source, and open to inspection by everyone who downloads them.
There are some optional shared libraries (`*.dll`, `*.dylib`, and `*.so`) included for performance. The source for any compiled pieces are provided within `alfcrypto_src.zip`. If this is a concern either delete the binary files or manually rebuild them.
There are some optional shared libraries (`*.dll`, `*.dylib`, and `*.so`) included for performance. The source for any compiled pieces are provided within `alfcrypto_src.zip`. If this is a concern either delete the binary files (there's fallback code in the plugin that allows it to work without these, it will just be slower) or manually rebuild them from source.
## What ebooks do these tools work on?
The Calibre plugin removes DRM from PDF, ePub, kePub (Kobo), eReader, Kindle (Mobipocket, KF8, Print Replica and Topaz) format ebooks using Adobe Adept, Barnes & Noble, Readium LCP, Amazon, Kobo and eReader DRM schemes.
The Calibre plugin removes DRM from PDF, ePub, kePub (Kobo), eReader, Kindle (Mobipocket, KF8, Print Replica and Topaz) format ebooks using Adobe Adept, Barnes & Noble, Amazon, Kobo and eReader DRM schemes. It used to remove Readium LCP DRM from ePub or PDF files in the past, but that functionality had to be removed due to a [DMCA takedown request](https://github.com/noDRM/DeDRM_tools/issues/18).
Note these tools do NOT crack the DRM. They simply allow the books owner to use the encryption key information already stored someplace on their computer or device to decrypt the ebook in the same manner the official ebook reading software uses.
@ -188,6 +188,9 @@ Amazon turned off backup for Kindle for Android, so the tools can no longer find
## Why don't the tools work on books from the Apple iBooks Store?
Apple regularly change the details of their DRM and so the tools in the main tools archive will not work with these ebooks. Apples Fairplay DRM scheme can be removed using Requiem if the appropriate version of iTunes can still be installed and used. See the post Apple and ebooks: iBookstore DRM and how to remove it at Apprentice Alf's blog for more details.
## Why don't the tools work with LCP-encrypted ebooks? / Error message about a "DMCA takedown"
Support for LCP DRM removal was included in the past, but Readium (the company who developed that particular DRM) has decided to [open a DMCA takedown request](https://github.com/github/dmca/blob/master/2022/01/2022-01-04-readium.md) in January 2022. This means that for legal reasons, this GitHun repository no longer contains the code needed to remove DRM from LCP-encrypted books. For more information please read [this bug report](https://github.com/noDRM/DeDRM_tools/issues/18).
## Ive got the tools archive and Ive read all the FAQs but I still cant install the tools and/or the DRM removal doesnt work
* Read the `ReadMe_Overview.txt` file in the top level of the tools archive
* Read the ReadMe file for the tool you want to use.
@ -196,7 +199,7 @@ Apple regularly change the details of their DRM and so the tools in the main too
## Who wrote these scripts?
The authors tend to identify themselves only by pseudonyms:
* The Adobe Adept and Barnes & Noble scripts were created by i♥cabbages
* The Readium LCP support for this plugin was created by NoDRM
* ~The Readium LCP support for this plugin was created by NoDRM~ (removed due to a DMCA takedown, see [#18](https://github.com/noDRM/DeDRM_tools/issues/18) )
* The Amazon Mobipocket and eReader scripts were created by The Dark Reverser
* The Amazon K4PC DRM/format was further decoded by Bart Simpson aka Skindle
* The Amazon K4 Mobi tool was created by by some_updates, mdlnx and others