expandTextDivs
more efficient by updating all styles at once instead of piecewise
I intended to provide proper benchmarking results here, as outlined in https://github.com/mozilla/pdf.js/wiki/Benchmarking-your-changes, but after wasting a couple of hours over the weekend getting weird results I gave up. It appears that there's a lot of, i.e. way too much, variance between subsequent runs of `text` tests for the results to be meaningful. (Previously I've only benchmarked `eq` tests, so I don't know if the `text` tests has never worked well or if it's a newer problem. For reference, please see the results of back-to-back benchmark runs on the current `master` with a *very* simple manifest file: [link here].) Instead I used `console.time/timeEnd` in `appendText` and `expandTextDivs` to be able to compare the performance with/without the patch. The entire viewer was (skip-cache) reloaded between measurements, and the result are available here: [link here]. Given the troubles I've had with benchmarking, I've not yet computed any statistics on the results (e.g. mean, variance, confidence intervals, and so on). However, just by looking at the data I think it's safe to say that this patch first of all doesn't seem to regress the current performance. Secondly it certainly looks *very* likely that this patch actually improves the performance, especially for the one-glyph-per-text-div case (cf. issue 7224). Re: issue 7584.
PDF.js
PDF.js is a Portable Document Format (PDF) viewer that is built with HTML5.
PDF.js is community-driven and supported by Mozilla Labs. Our goal is to create a general-purpose, web standards-based platform for parsing and rendering PDFs.
Contributing
PDF.js is an open source project and always looking for more contributors. To get involved checkout:
- Issue Reporting Guide
- Code Contribution Guide
- Frequently Asked Questions
- Good Beginner Bugs
- Priorities
- Attend a Public Meeting
For further questions or guidance feel free to stop by #pdfjs on irc.mozilla.org.
Getting Started
Online demo
Browser Extensions
Firefox (and Seamonkey)
PDF.js is built into version 19+ of Firefox, however one extension is still available:
-
Development Version - This extension is mainly intended for developers/testers, and it is updated every time new code is merged into the PDF.js codebase. It should be quite stable, but might break from time to time.
-
Please note that the extension is not guaranteed to be compatible with Firefox versions that are older than the current ESR version, see the Release Calendar.
-
The extension should also work in Seamonkey, provided that it is based on a Firefox version as above (see Which version of Firefox does SeaMonkey 2.x correspond with?), but we do not guarantee compatibility.
-
Chrome
- The official extension for Chrome can be installed from the Chrome Web Store. This extension is maintained by @Rob--W.
- Build Your Own - Get the code as explained below and issue
gulp chromium
. Then open Chrome, go toTools > Extension
and load the (unpackaged) extension from the directorybuild/chromium
.
Getting the Code
To get a local copy of the current code, clone it using git:
$ git clone git://github.com/mozilla/pdf.js.git
$ cd pdf.js
Next, install Node.js via the official package or via nvm. You need to install the gulp package globally (see also gulp's getting started):
$ npm install -g gulp-cli
If everything worked out, install all dependencies for PDF.js:
$ npm install
Finally you need to start a local web server as some browsers do not allow opening PDF files using a file:// URL. Run
$ gulp server
and then you can open
It is also possible to view all test PDF files on the right side by opening
Building PDF.js
In order to bundle all src/
files into two productions scripts and build the generic
viewer, issue:
$ gulp generic
This will generate pdf.js
and pdf.worker.js
in the build/generic/build/
directory.
Both scripts are needed but only pdf.js
needs to be included since pdf.worker.js
will
be loaded by pdf.js
. If you want to support more browsers than Firefox you'll also need
to include compatibility.js
from build/generic/web/
. The PDF.js files are large and
should be minified for production.
Using PDF.js in a web application
To use PDF.js in a web application you can choose to use a pre-built version of the library
or to build it from source. We supply pre-built versions for usage with NPM and Bower under
the pdfjs-dist
name. For more information and examples please refer to the
wiki page on this subject.
Learning
You can play with the PDF.js API directly from your browser through the live demos below:
The repo contains a hello world example that you can run locally:
For an introduction to the PDF.js code, check out the presentation by our contributor Julian Viereck:
You can read more about PDF.js here:
- http://andreasgal.com/2011/06/15/pdf-js/
- http://blog.mozilla.com/cjones/2011/06/15/overview-of-pdf-js-guts/
Even more learning resources can be found at:
Questions
Check out our FAQs and get answers to common questions:
Talk to us on IRC:
- #pdfjs on irc.mozilla.org
Join our mailing list:
Subscribe either using lists.mozilla.org or Google Groups:
- https://lists.mozilla.org/listinfo/dev-pdf-js
- https://groups.google.com/group/mozilla.dev.pdf-js/topics
Follow us on twitter: @pdfjs
Weekly Public Meetings