Computer Laboratory

Course pages 2014–15

Instructions for lecturers

Most lecturers now place material for their students on the web. To support this, the Computer Laboratory creates each year a new set of directories and page templates, to ensure that outdated material is not left in the main student access path.

Where are the files?

Each course has its own directory, which this year can be found at:

  /anfs/www/html/teaching/1415/courseid                under Unix/Linux
= \\filer\www\html\teaching\1415\courseid              under Windows
= http://www.cl.cam.ac.uk/teaching/1415/courseid/      web pages
= http://www.cl.cam.ac.uk/teaching/current/courseid/   year-invariant alias

Please consult the lecturer index to find your pages.

You can access the /anfs/www/... path above on our central fileserver directly on any lab-managed Linux computer. If you lack one, please use ssh or PuTTY to log into one of the Linux timesharing servers (e.g., slogin.cl.cam.ac.uk).

External lecturers: If you do not have a Linux login at the department, please contact sys-admin@cl.cam.ac.uk, and provide them with an ssh public key and the IP addresses from which you want to login, and they will set up everything for you. Note that password-based login from outside the Computer Laboratory is disabled, hence the need to use Kerberos or public-key authentication. See our sys-admin ssh pages for details. Alternatively, our librarian or student administrators can also place materials for you onto the web server.

How should I update the pages?

An easy to edit, undecorated, “bare-bones” HTML file, materials-b.html, has been placed into your directory, where you can add any information that you would like to make available to your students, such as links to lecture notes and exercise sheets. The actual “Course materials” page, materials.html, is automatically generated from that file after you type "make" under Linux. (If there is no materials-b.html file, you can edit index-b.html instead, but this applies only to a few pages where there is no syllabus.)

To recreate all the *.html files from the respective *-b.html files, run the UNIX command:

  /anfs/www/tools/bin/ucampas -r

Simply typing “make” will achieve the same, thanks to the also provided Makefile.

Access rights

A principal lecturer has been assigned to each course. This person is the owner of the directory.

All the course directories also belong to Unix group “teaching”, which comprises all the lecturers teaching a course this year, plus teaching administrators. The directories are by default writeable to everyone in this group. This makes collaboration easier in courses taught by several people, and also allows administrators to help with placing materials online or fixing typos. To preserve group write access, make sure the Linux command “umask” outputs “0002”. (If you prefer to disable group write access, you can easily do this with the Linux tools chgrp or chmod.)

Syllabus page

The first tab of each course page (index.html) shows an HTML version of the syllabus. You are not supposed to edit that yourself, as the syllabus is edited and frozen in August and substantial changes require teaching-committee approval. To update the LaTeX source (/homes/ncc25/syllabus/coursesetc/) of your undergraduate syllabus, please contact the Teaching Administrator (Dinah Pounds). To update the HTML source (/anfs/www/html/teaching/current/syllabi/) of your Part III/MPhil syllabus, please contact the Graduate Administrator (Lise Gough).

Materials for supervisors

Lecturers in Part IA/IB/II are expected to prepare a Supervision Guide for supervisors of the course, and this is what the page “Information for supervisors” in subdirectory supervisors/ is for. Access to this page is restricted via Raven.

Edit the file supervisors/.htaccess in order to grant access to individual supervisors that contact you, as explained in the comments in that file. (This file also explains how you can grant access to your students after the end of lectures and supervisions.)

Students can now find themselves in our archive of past Tripos exam papers also solution notes. As a result, supervisors can no longer rely on past exam questions as exercise material and need separate exercise sheets and solution notes.

Assessment page

Part III and MPhil ACS modules have an assessment-b.html page, where you need to explain in detail how you are going to assess the course. This might include information about deadlines for essays or the dates and details of exams, as well as how the final mark will be calculated from all the assessed student contributions.

Video recordings

Both LT1 and LT2 are equipped with a lecture recorder that can be used to record both the microphone audio and the projected video signal of your lecture. To use it, simply press the big red button on the bench after you have set up your presentation display (i.e., first slide) and a few seconds before you start to speak. The button will light up during the recording. Press it again at the end of your lecture to finish the recording.

The *.avi files that the device records (1024x768, 30 Hz) will show up within a few days in /anfs/www-video/incoming/ on the departmental filer. In order to make them accessible via the departmental web server, you need to convert the file format and store the result in a web directory.

If you would like to add these videos to your course materials pages, please create and set-up a dedicated directory and index web page for your course, by calling the script

$ /anfs/www/VH-cl/scripts/make-video-dir

This asks for your courseid and then creates and links a video directory for your course under /anfs/www-video/teaching/1314/courseid. Read and follow the instructions given by this script carefully. The script will produce a Makefile that does most of the work, but you still have to edit it to specify the list of recordings from /anfs/www-video/incoming/ that belong to your course. The filenames contain the room, Bigendian date, weekday and start time (lt1-yymmdd-fri-hhmm.avi), such that bash pattern matching can be used to make the selection. Example:

# Unix Tools: LT1 2013 Oct 31 - Dec 3 TT 11:00-12:00
RECORDINGS=lt1-13{1031,1[12]??}-t??-110?.avi

Make sure that you have the avconv tool installed that the Makefile calls to convert your video files into compacter formats suitable for recent HTML5 web browsers. On Ubuntu Linux:

$ cl-asuser apt-get install libav-tools libavcodec-extra-53

You might also want to install a video player for previewing (e.g., smplayer, vlc).

We expect the bulk of /anfs/www-video/teaching to consist of unedited recordings, which we are likely to delete each year. They are mainly intended for current students with disabilities who are already allowed to make their own audio recordings. If you want to preserve your recordings, please copy them elsewhere.

These video recordings are still experimental. Known caveats:

  • For quota and backup-space reasons, we currently keep video recordings in a separate filer directory /anfs/www-video, and not in the normal /anfs/www tree. The make-video-dir script sets up symlinks to hide this fact.
  • The available encoder for the WebM/VP8 video format needed by Firefox under Linux is extremely slow, therefore we currently reduce the frame rate of the video recording from 30 Hz to 1 Hz there.

Editing video is complex, time-consuming, and probably not worth for these in-house recordings. Enthusiasts who want to change something might try an interactive video editor (e.g., openshot, pitivi, kdenlive, lightworks). The avconv/ffmpeg tool also offers many filters and parameters to tweak and edit videos.

More information