firefox


Netflix error f7701-1003 on Ubuntu

Recently we got the error F7701-1003 on Netflix after an update on the operating system was performed. To repair it we installed the package libavcodec-extra using the following command:

sudo apt install libavcodec-extra;

After the installation was complete, we just restarted the browser and Netflix was operating again as expected.

Below is the basic information about the package that was installed:

Package: libavcodec-extra
Version: 7:4.2.4-1ubuntu0.1
Priority: extra
Section: universe/libs
Source: ffmpeg
Origin: Ubuntu
Maintainer: Ubuntu Developers <[email protected]>
Original-Maintainer: Debian Multimedia Maintainers <[email protected]>
Bugs: https://bugs.launchpad.net/ubuntu/+filebug
Installed-Size: 65,5 kB
Depends: libavcodec-extra58 (= 7:4.2.4-1ubuntu0.1)
Homepage: https://ffmpeg.org/
Download-Size: 14,8 kB
APT-Manual-Installed: yes
APT-Sources: http://cy.archive.ubuntu.com/ubuntu focal-updates/universe amd64 Packages
Description: FFmpeg library with extra codecs (metapackage)
 FFmpeg is the leading multimedia framework, able to decode, encode, transcode,
 mux, demux, stream, filter and play pretty much anything that humans and
 machines have created. It supports the most obscure ancient formats up to the
 cutting edge.
 .
 This metapackage depends on the latest version of the libavcodec variant
 that offers additional codec support. Application packages can depend
 on it if they require or suggest this variant in a robust manner.

Package: libavcodec-extra
Version: 7:4.2.2-1ubuntu1
Priority: extra
Section: universe/libs
Source: ffmpeg
Origin: Ubuntu
Maintainer: Ubuntu Developers <[email protected]>
Original-Maintainer: Debian Multimedia Maintainers <[email protected]>
Bugs: https://bugs.launchpad.net/ubuntu/+filebug
Installed-Size: 65,5 kB
Depends: libavcodec-extra58 (= 7:4.2.2-1ubuntu1)
Homepage: https://ffmpeg.org/
Download-Size: 14,8 kB
APT-Sources: http://cy.archive.ubuntu.com/ubuntu focal/universe amd64 Packages
Description: FFmpeg library with extra codecs (metapackage)
 FFmpeg is the leading multimedia framework, able to decode, encode, transcode,
 mux, demux, stream, filter and play pretty much anything that humans and
 machines have created. It supports the most obscure ancient formats up to the
 cutting edge.
 .
 This metapackage depends on the latest version of the libavcodec variant
 that offers additional codec support. Application packages can depend
 on it if they require or suggest this variant in a robust manner.

How to see the isc2.org Webex Online Instructor-Led courses using your browser only

Recently, we registered for some online instructor-led courses in isc2.org.
We were using a Ubuntu GNU/Linux machine with the latest Firefox / Chromium and even Chrome versions.
There was something wrong with the meeting. When clicking on the Join button, instead of loading, it was trying to download a java applet configuration (CiscoWebExServlet).
After reading about those files and a lot of work, which included setting up a 32-bit version of Firefox with a 32-bit version of the Oracle JRE and installing IcedTea, we managed to connect to the meeting, but we had no audio.

When trying to connect to the meeting via phone, we got no voice.

When trying the mobile application, it required a password, which was never supplied.

So, we had to find another way in!

Using the Network tab of the Inspect Element menu, we clicked on the gear in the upper right corner and enabled the Persist Log option. Then we clicked on the Join button and logged all redirects with their parameters.

In isc2.org virtual class, the Join button has a custom link to https://www.cirqlive.com/, which is used to join the meetings.
Once you click on that button, the browser follows several redirects between webex.com and cirqlive.com, and it ends up on this page https://isc2training.webex.com/tc3300/webcomponents/docshow/meetingframe.do?siteurl=isc2training asking to download the servlet.

From the logged redirects of the above link, we got the request to https://isc2training.webex.com/tc3300/m.do where we got the meeting ID and password in the POST parameters.
Then went to https://signin.webex.com/join added the meeting ID, which led us to this page https://isc2training.webex.com/isc2training/e.php?AT=SI&From=GPS&MK=XXXXXXXX (using fake meeting ID)
We filled in the Session Password and clicked on Join by browser, and we could join as expected.


Fedora 27: Install OBS Studio

In order to record a few desktop sessions on our Fedora GNU/Linux machine, we decided to use the OBS Studio as it appeared to be a very powerful tool.
Unfortunately, this software does not ship with the official repositories so we had to install it from the  rpmfusion.org repository using the following commands.

#Enable access to both the free and the nonfree repository
#free repository: for Open Source Software (as defined by the Fedora Licensing Guidelines) which the Fedora project cannot ship due to other reasons
#nonfree repository: for redistributable software that is not Open Source Software (as defined by the Fedora Licensing Guidelines); this includes software with publicly available source-code that has "no commercial use"-like restrictions 
sudo dnf install https://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-$(rpm -E %fedora).noarch.rpm https://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-$(rpm -E %fedora).noarch.rpm;

#Perform the installation
sudo dnf install obs-studio;

Background:

RPM Fusion provides software that the Fedora Project or Red Hat don’t want to ship. That software is provided as precompiled RPMs.

Codecs in Fedora

By default Fedora does not ship with several codecs whose license is not free.
So we had to install a few packages manually and be able to playback or process sever multimedia formats.

Specifically we installed the following plugins and libraries for GStreamer (needed for the Totem Movie Player):

  1. gstreamer1-libav: This package provides libav-based GStreamer plug-ins.
    Libav is a free software project, forked from FFmpeg in 2011, that produces libraries and programs for handling multimedia data.
  2. gstreamer1-plugins-good: GStreamer Good Plugins is a collection of well-supported plugins of good quality and under the LGPL license.
  3. gstreamer-ffmpeg: This package provides FFmpeg-based GStreamer plug-ins.

GStreamer is a streaming media framework, based on graphs of filters which operate on media data. Applications using this library can do anything from real-time sound processing to playing videos, and just about anything else media-related. Its plugin-based architecture means that new data types or processing capabilities can be added simply by installing new plugins.

The command to install these packages was:

sudo dnf install gstreamer1-plugins-good gstreamer-ffmpeg gstreamer1-libav;

Additional h264 – h.264 Codec – Optional

Following, we decided to install the OpenH264 codec implementation and its extensions for Firefox and gstreamer.

Cisco provides an OpenH264 codec (as a source and a binary), which is their of implementation H.264 codec, and they cover all licensing fees for all parties using their binary. This codec allows you to use H.264 in WebRTC with gstreamer and Firefox. It does not enable generic H.264 playback, only WebRTC.

The code source is available at https://github.com/cisco/openh264 under a BSD license. The binary is released under this agreement from Cisco: http://www.openh264.org/BINARY_LICENSE.txt

Upstream Firefox versions download and install the OpenH264 plugin by default automatically. Due to it’s binary nature, Fedora disables this automatic download.

From: https://fedoraproject.org/wiki/OpenH264

To install the codec we performed the three following steps:

sudo dnf config-manager --set-enabled fedora-cisco-openh264;

sudo dnf upgrade;

sudo dnf install gstreamer1-plugin-openh264 mozilla-openh264;

# Afterwards you need open Firefox, go to menu -> Add-ons -> Plugins and enable OpenH264 plugin.

Bonus: Black Screen Issue

If you are having issues with the OBS Studio black screen bug, have a look at this post, it may be able to help you.