How to Read PDFs in PPL

Submitted by polymonyrks on Sat, 08/06/2022 - 10:59

(This article is for engineers (somewhat technical).)

Since PPL runs on Safari, it is necessary to convert PDFs to HTML format that can be read by Safari.

pdf2htmlEX converts PDFs to HTML with almost no layout errors, and it seems to be used by ACM Digital Library and others. Therefore, PPL supports HTML converted in pdf2htmlEX format.

Sample: Patent Law (Source here)

To use, click the upper left button to start, and after starting, click the left button to Undo, Reset, and the right button to show/hide the table of contents.

The following is how to install pdf2htmlEX.

0. Online Converter

Online converters (e.g. convertio uses pdf2htmlEX to convert PDF to HTML) may also be available. The following 1, 2, and 3 are explanations in case you install it by yourself. If you want to use an online converter, please go to 4.

1. Installation


2. Replace the document reader

(If you have chosen "4.1. Load offline HTML files" in "4. File Preparation" described below, this step 2 is not necessary.)
The JS file (pdf2htmlEX.min.js) for the default reader prepared by pdf2htmlEX is modified to enable 1. the ability to zoom in at maximum width and 2. on/off of the table of contents. It will work without modifying the file, but if you modify the file, you will be able to execute 1. and 2. from the PPL button. (It will be done differently if introduced with docker).

2. 1. locating pdf2htmlEX.min.js

In a terminal, type the following command to find the location.
pdf2htmlEX -v

2.2. Replacing the file

Replace pdf2htmlEX.min.js in that location with this file.

3. run pdf2HTMLEx

The following command is recommended. xxx.pdf (target file name) and /home/xxx/Desktop (output destination) can be rewritten as appropriate.

pdf2htmlEX xxx.pdf --dest-dir /home/xxx/Desktop --tounicode 1 --decompose-ligature 1 --turn-off-ligatures 1

Now html readable by PPL is generated.


4. File Preparation

4.1. Loading offline HTML files

This will be supported in the next update (ver. 2.0.5).

4.1.1. Show file load button

The file load button is hidden by default. Set local HTML Toggle to Yes in the options screen as shown in the image below.



4.1.2. file selection

Do as shown in the video below. Open any page, select the button you have just activated (it appears a little above the Undo and Reset buttons), and select the local HTML.



4. 2 Uploading to the server

It is also possible to upload html files to a server for reading. Hosting is required (you cannot just select a file uploaded to DropBox, etc.).