This page is mainly to hold notes on the two systems of lecture recording
currently in use in Psychology at GU (Glasgow University).
But note you can consider using recordings of
broadcast TV.
Section 5: Editing recordings
- There has at GU for many years been occasional recording of special
lectures, originally by manned video camera crews.
- About 2005, we started "podcasting" lectures. Actually, this was
recording, using handheld audio recorders from which files were uploaded and
mostly distributed as MP3 files.
I have a page about our early initiatives on
this.
- For the last few years, a number of lecturers have sometimes used
Camtasia or other systems, running on their laptops from which they gave
lectures, to capture both video and audio from lectures.
- Lately, Echo360 has been installed in some of the large lecture theatres,
and is used to record lectures more automatically (driven off central
software: no need to set it going locally); and the resulting records are
stored centrally for access by students and other users.
Its use is growing, but is by no means (yet) standard practice.
This section is some notes on doing audio lecture recording now (Sept. 2014),
in the context of moodle 2.
The default Moodle2 audio player doesn't allow downloads (for student's ipod
players), and doesn't allow fast forward or any way to move forward and back.
What we probably want (what I want for level 3 lecture recordings) is to pass
the file as a link (URL) so that the user gets whatever audio player they have
installed in their browser on whatever device they are using at that moment.
Phil has been uploading and installing recordings as File resources.
All that has to be done is to edit the settings in Moodle for each such File
resource:
Click tab/section "Appearance" -- select "In pop-up" not "automatic".
I might add that Moodle is doing the file protection we want: Even if I copy
a link (URL) and put it outside Moodle, users can't play or download it
unless:
1) They can login to Moodle (all staff and students, but very few outside GU,
can do this.
2) They are enrolled on the course where the resource is stored.
For level 3 CHIP: that is only enrolled students, 3 staff (and a
surprising number of the Moodle team).
Proposals?
1) I'm not fussed about my own lecture recordings, so no need to get right
this minute from my viewpoint, but I agree with Phil we want a general agreed
policy.
2) Students downloading.
a) Historically, but possibly not now, it was important to many students to get
a copy of the audio on to players they carried round. Hence I regard this as a
key requirement until someone shows no students do this now.
b) A tech-savy student can download them from the poor moodle player: you ask
your browser to show the source of the page on which the Moodle player is
operating, search the blizzard of HTML code for "Source" or ".mp3" and you get
the underlying URL of the resource, and get it.
Thus "protection" stops the naive, but not the informed but malicious.
3) An expert I consulted said the trend now was not to embed players, but pass
the file direct to the user's browser; partly because it will know better (be
configured better) to deal with it depending on whether it is a phone, tablet,
....; which we and Moodle cannot know.
4) I agree we should make clear to the students that lecture recordings should
be treated essentially like copies of library PDFs of journal papers: never
passed on or put on public websites by students. The current handbooks used
not to do that clearly, but now do (in 2015-6).
This section is about the Echo360 lecture capture
system which is now being rolled out in this university, and can also capture
just audio, but also can capture video of the slides and/or the speaker.
For now, just some pointers.
Notes on using it
For (students) watching a recorded lecture, a great feature is being able to
jump to points in the lecture by clicking on any slide. While playing a
recording, click on the top item "Scenes" in the list of "Apps" in the right
hand column, to show a scrolling list of the slides.
Logging / "analytics":
Info is sliced at every few mins; then combined with gaps of user attention
< 10 mins ignored; and a "view" is one chunk of combined slices.
So just 2 mins play should show up.
The slicing may make "average completion" pretty inaccurate for short videos.
But I didn't see anything update because of my viewing in either view:
- Student view: list of videos on a course with thumbnails.
The stats here take maybe an hour to update. They are somewhat adjusted to
take account of one person looking many times vs. different people; and one
person viewing with some gaps vs. apparently looking several times.
- Staff/editor view of the list of presentations.
This takes a day (overnight) to update the count of "views". This count does
not correspond to the adjusted stats above: may be a crude count of all
accesses to a recording.
Security / privacy is given by:
a) All recordings are on a server, which every user must login to with their GUID.
b) A course is offered to a class by making an obscure URL available to them
e.g. http://moodle2.gla.ac.uk/mod/url/view.php?id=469500
Thus it is unlikely that other students will find it. Placing the link on
Moodle, behind Moodle's login wall for a given course, gives moderate
security.
c) Sets of recordings "owned" by a given person (typically the lecturer
giving a course being recorded) are accessible (with editing and deletion
rights) only to that owner(s):
https://lectures.gla.ac.uk/
The second Echo window is the one for playing recordings:
https://lectures.gla.ac.uk/ess/portal/section/bc9cff6c-c1b8-40c7-8652-0eeee2525182
Lecturer-owners can edit the title of any lecture from the window for playing
them. (Select = highlight a lecture; click on the pencil icon by the title at
the top of the right hand panel beside the list of titles.)
Slides may not be recorded usefully for some settings of screen resolution on
the computer displaying the slides, even though they display correctly on the
lecture theatre data projector itself.
(1024 X 768 is one that works for Echo360 recordings.)
How to check? Too hard for doing at the last minute on getting to the LT.
But something like:
Be in the LT and a booked recording has started;
Put up the slides so they are projected.
Also have a window looking at the recording .... (updates only every 30secs).
....
Editing
- Go to list of recordings: https://lectures.gla.ac.uk/
- Hover over the recording you want -- a tiny hor.menu appears -- click "edit".
- The "Edit Echo" screen lets you change descriptions, press "Save" at the
bottom of the page, and these appear at once.
- OR to edit the recording itself, press "Edit media" at the bottom of the
page; and you get a different Edit screen.
- You can drag trim tabs etc.; then press "Save" against each edit spec. that
appears AND press "[tick]" to commit it.
- After editing (and "Previewing" the result), Press "Save" in the top tabs
to irreversibly make and publish the edits.
Press "Process edits"
Return to first screen but press your browser's Back button or
press "Cancel" but not "Save".
It takes about 30mins for the edits to appear in the recording.
You see this when you "Play" it. But if you try to re-edit it, you are back
with the original unedited version.
But another way is to use software built-in to a lecturer's laptop, asusming
they take a laptop to the lecture theatre normally.
"Camtasia" is one such system. But also: free Mac software "Keynote" does
this, using the laptop's built in microphones and camera and screen display of
slides. This works surprisingly adequately.
- Foreign students, for whom English is not their first language.
They often have trouble understanding the lecture as they go, but are helped
by being able to listen to it again (with a pause button).
They need the recording to be posted at once if they are to understand the
next lecture, which is frequently the next day.
- Students who have to miss a particular lecture e.g. for a doctor's
appointment. Again, they need to have access almost immediately to the
recording.
- This is particularly acute for courses with lectures only 24 hours
apart, where they need to listen to it in order to understand the next day's
lecture. In my dept. (pscyhology) this is true of lectures in level 1, level 2,
and at least one course in level 3. This then puts a premium on systems like
Echo360 which publish recordings within an hour or less from the end of the
lecture. This means not having to wait for a human to find time for this.
- Revision: careful re-listening. This would be much more useful
if each recording had a tagged index i.e. a way of jumping direct to various
labelled points. This is true of both video and audio recordings.
Solution: (1) each slide should be a live link that jumps into the audio
at the appropriate point. (2) Someone / students create tags: target points in
the recording described by tag-words.
- Students in my class today tell me that they
listen in class without taking notes (get too confused doing 2 things at
once); then 4/5 of them said they had already listened to some recordings
(only week 3 of the course); that they promptly re-listen to about 50% of
lectures; that the combination of the textbook chapter, my slides handout, and
re-listening to the recording was good, and was normal practice for them now.
Problems
- Copyrighted images on lecture slides must not be publicly distributed
- Confidential material dealt with in class discussions.
- Participation vs. canned delivery.
Solution: do not record classes which are essentially about participation.
- Mac Quicktime reads in .mov and .aiff files (and .mp3); but not .wav
- Quicktime is not my default app for opening these files; but can select
the file, click Open-with lets me do it.
- Mac Quicktime has a fast Trim function for lopping off unwanted start and
end portions of a recording: easier and quick to use than Audacity.
- Mac Quicktime exports only .m4a, .aifc
- Echo360 also has an editor; fairly easy to use, especially for trimming.
Obviously it edits the videos as well as the audio. However, this is only
possible while it retains all the original files: after a year or less only a
playable (but not editable) form remains.
- Audacity reads in uncompressed fast, but .aifc also fast.
- Audacity (re)exports in multiple formats, esp. the compressed .mp3 format.
(Export takes 4 min.s for 50 min. lecture).
- Audacity: has a much more general editor, but I still have trouble with
the user interface.
- Currently we have been saving audio files at quite high resolution. File
sizes depend on this. A rough trial on one of my lecture recordings (of about
50 mins in length) shows this:
- .mov (uncompressed, from the recorder): 69.4MB
- .mp3 (? kbps; what Phil uses): 70.5 MB
- .mp3 (128 kbps): 45.4 MB
- .mp3 (64 kbps): 22.7 MB (Sounds fine to me)
- .mp3 (32 kbps): 11.4 MB (Audible, but sounds worse than the others)
So for faster up/down-loading, smaller files are better for everyone, and
compressing them to 64kbps and getting smaller than one third the original
file size, may be best. However this is a single trial, with a recording from
a tie-clip mike as is normal for dept. recordings: so this might not
generalise.
- I have a neat recorder that looks like a USB pendrive.
My recipe for converting its .WAV files is:
- Drag and rename .WAV file from pendrive/recorder
- Open it in Audacity; Re-save it as .aiff [Mac non-compressed]
- Open the .aiff in Quicktime
- Trim there, and save (as .aifc)
- Re-read .aifc into Audacity
- Export it as .mp3
- Audacity recipe for trim / edit out the middle.
- When read in ...
- Select "I" mini-icon tool for specifying range by dragging.
- (MagGlass with '+' expands zoom)
- X Cuts it
- It won't do it while playing; have to get <----> in top margin
AND greyed out to show selection; ....
- Audacity recipe for merging files
- Read in first file; then
- File -- Import -- Audio to get 2nd file
(You get both, one below the other)
- Use the time shift tool to displace 2nd one to right, having
selected the whole of the 2nd one.
The tool looks like <---> mini-icon
- Then just export or save the result.
- Audacity recipe for splitting files
- [Don't use Audacity but Quicktime, and a double trim]
- Read original file into Audacity, then out into .aiff; close.
- Duplicate that file (2 sep names for the 2 parts)
- Trim 1: file 1, trim 2nd half of talk off
- Trim 2: file 2, trim 1st half of talk off
- Then as above, for each separately:
- -- Read .aiff into Audacity, and export as .mp3.
Web site logical path:
[www.psy.gla.ac.uk]
[~steve]
[ipod]
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