Category: Video and Multimedia

Mechanical Turk for transcribing audio recordings and captioning

Posted on June 13, 2013November 19, 2013 by ellen

I sometimes record lectures or meetings for later reference, and have found Mechanical Turk to be an efficient and affordable method for transcribing them. It can be quite confusing to get started using MTurk though, and the available blogs on the subject don’t really help you navigate the current MTurk interface, so here is the step-by-step process I use to have a lecture transcribed:

Cut your audio into 5 or 10 minute clips

Download Audacity – a free audio editing tool that works on both Windows and Mac.

Import your voice-recording file. (File > Import >Audio)

If you see a warning about FFMpeg being missing, just ignore it.

Audio, but no video on GoToMeeting WMV videos (G2M3 format)

Posted on October 1, 2010 by ellen

The other day I came across a Windows Media file that would not play correctly on any player on Mac or PC. The audio track played fine, but there was no video – it was black. Nor would any encoding software convert the file to Flash Video, which is what was really needed.

Looking in Quicktime’s Movie Inspector I could at least tell that the video was in “G2M3” format. G2M3 is a proprietary codec, used in GoToMeeting by default when you save a recorded session.

GoToMeeting allows users to record meetings in either G2M3 or in standard Windows Media format. The latter choice is likely to be overlooked by most users, so chances are their recordings will be un-viewable and un-convertable on non-GoToMeeting software. However, even if a GoToMeeting session has been recorded in the proprietary format you can still convert the file after the fact using a little application called g2mtranscoder that is installed in the GoToMeeting folder.

Microsoft Web Platform installer: Drupal on IIS, the easy way.

Posted on July 9, 2010 by ellen

If you work with Windows servers, then you have probably gotten used to doing without the many opensource web applications taken for granted outside the enterprise environment. Drupal, WordPress, phpBB, Moodle, etc. were all out of reach. Yes, it was possible to install PHP and mySQL, but it took a level of commitment and dogged troubleshooting persistence that few people are willing to undertake.

Well, now you can have your enterprise cake and your opensource software too! Microsoft’s Web Platform Installer, introduced a couple of years ago, makes the process of installing all those LAMP-style web apps easy. When I say easy, I really mean easy! It just works!

Use inexpensive Korg Controllers to control Logic Pro interfaces

Posted on July 5, 2010 by ellen

Logic Pro is a popular digital audio workstation/ Midi sequencer for the Mac. It contains many virtual models of mixers, effects, synths, drum machines and sequencers. Since the typical audio gear requires simultaneous fine-grained control of multiple parameters, the typical adjustment method is with a knob or slider control.

A standard mouse is not the best way to control such a UI. Many companies sell USB-Midi control surfaces with knobs and faders that allow real-time control of the sound using Logic’s virtual mixers and effects. However these can be very expensive. For those who are on a budget it can be a high price to pay to get started.

Multiple JW players on a page, revised for JW Player 4.7

Posted on May 24, 2010September 6, 2018 by ellen

The JW Player is a very popular open-source media player which not only supports many video, audio and image formats, but has many scriptable behaviors. Here we’ll make use of the JavaScript API to generate as many players as you want on a page. The generated players all have separate event listeners to keep them from interfering with each other. Events or actions executed in one player do not affect others.

Article Outline

Add placeholders for each player

Playlists

Call the init function

This is a new version of that was compatible with an earlier version of the JW Player. This one has been updated to work with JW Player 4.7.761 and later.

JW FLV player with Javascript playlist

Posted on December 15, 2009 by ellen

This is an example of how to create a javascript-based Playlist selector for a JW FLV player. The playlist selector menu has 3 sections that toggle open and closed when you click on them. This allows the user to switch playlists, choosing from various topics.

The source code has not been cleaned up, but you should be able to get an idea of how to set this up from it.

Can’t export more than 30 seconds of Windows Media from Quicktime

Posted on November 19, 2009November 22, 2013 by ellen

In the last year or so, I got used to being able to export to just about any format from Quicktime Pro using Quicktime Conversions. When I upgraded to Snow Leopard, I installed Flip4Mac’s Snow

Infinite JW FLV players on a page, with error catching for Red5 bug

Posted on October 30, 2009 by ellen

NOTE: this has been revised to make it more flexible, and allow multiple streamers and multiple video types, using the same code.

This is a script that allows you to add as many JW FLV players to a page as you want, using a single block of code. The players all have separate event listeners to keep them from interfering with each other. Events or actions executed in one player do not affect others.

This particular demo also corrects for a problem we have noticed recently with Red5, where RTMP streams will hang with a “BUFFER.EMPTY” status code. I’ve set up meta-monitoring so that it catches “BUFFER.EMPTY” codes and starts the player up again a little bit previous to the break. It creates player names and function names dynamically, based on how many players you request. If this function seems to be giving you problems, if your videos start jumping back and restarting a lot, search for the following line and comment it out by adding “//” in front of it:

window["player_"+obj.id].sendEvent('SEEK', parseInt(window["positionarray_"+obj.id][3])+100);

We’ve also had problems with some videos that simply refuse to stream, although they will play using progressive download. You can use a mixture of streaming and non-streaming by altering the playlist for each video.

JW FLV Player and Red5 apparent buffering bug

Posted on October 27, 2009 by ellen

Update 12-18-09: Longtailvideo has apparently resolved this bug with its player v.4.7beta. At this time v. 5 does NOT have the fix in it. The code changes that fixed the bug can be seen here: [Changes to RTMPModel.as]

A few months ago, we installed Red5 0.7.0 on a Windows server to stream Flash video inside the firewall. This server is used mainly to stream short clips that are embedded in learning modules.

The JW FLV player v. 4.6 is included in the learning module template and enables us to display the videos with a high degree of flexibility.

Example of a player that contains multiple short video clips.
The player generates a navigation listing on the right from the XML playlist.

Flip4Mac WMV player constantly “importing” in background

Posted on October 8, 2009 by ellen

On upgrading to Snow Leopard, a little window with a progress bar started appearing: “Flip4Mac importing”. No reference to what was being imported or why. This has apparently been fixed in Flip4Mac WMV 2.3.0.11-Beta. It’s