Interested in exploring podcasting as a technique for distributing multimedia content on the Internet? To understand this technology, we will begin by exploring RSS feeds. RSS underlies podcasting.
RSS stands for Really Simple Syndication. It has been around for several years, but became popular as blogs (web logs) grew in use. The idea is to have an easy way to distribute fresh content regularly to interested readers without having them have to browse back to the originating site. For example, a blogger might post a new "story or "commentary" every 6 hours. A reader "subscibes" to a service to have this content automatically downloaded to their computer. Think of this as the Internet equivalent to subscibing to a newspaper or magazine automatically delivered to you. The content is called "syndicated content." RSS is a system under which someone can set up a "feed" to automatically receive a notice of this new content (perhaps a title) and can click to download it if they want it. The person receiving the content uses a program (might be a browser or a different program) called an aggregator. The aggregator program receives "headlines" or "titles" of newly posted items in feeds or blogs that the user has subscribed to. To make this more concrete, consider the following actual examples:
CNN offers an RSS feed of its headlines. To see this, in your favorite browser go to www.cnn.com. In your browser you'll see:
See the RSS logo circled on the right. (In other browsers, a different icon might appear. For example, Firefox uses: .) If you click the icon, you can subscribe to get an RSS feed from the CNN site. Firefox itself is an aggregator program, so it is used in the discussion that follows. If you subscribe, a "live bookmark" is created so that if you go to the Bookmarks pulldown and go to Bookmarks Toolbar Folder, you see the headlines as if they were bookmarks. These will change automatically for you. You have subscribed to CNN's syndicated content. See the example below (from the Spring of 06):
In the following, we've subscribed to two other RSS feeds. The first is called "Blog for America" and the second is a blog of tips on digital photography.
So what does RSS have to do with podcasting? Although any posted audio or video file may get called a podcast, the term podcast refers to an RSS feed of audio and/or graphics and video files that is used with iTunes as the aggregator program. The iTunes program (free for both Windows and Macintosh computers) dominates digital audio and podcasting in much the same way Photoshop dominates graphics editing. It is very easy to use and it integrates easily with iPods. (It is not necessary to have or use an iPod for creating or subscribing to podcasts.)
The basic steps to create a podcast are the following:
1) Record content to a computer. Use a microphone attached to a computer, a wireless microphone tranmitting to a computer, or an iPod with a microphone attachment that is then synchronized with a computer. In any case, create an audio file with content. We will explore below and elsewhere techniques for doing this.
2) Edit the content (or not). To edit, use Garage Band on an Apple computer or Audacity on Windows. Garage Band editing is described below.
3) Publish the file to a podcast server. In this seminar, you will use a special server account and a server program called weblog to "publish" your own podcasts.
4) You and others can then subscribe to your podcast (as well as those of anyone else). Generally this is done using a web browser. Connect to the server's site and click appropriate buttons to subscribe. This will set up a new item in iTunes podcast listings.
Before September, we'll have you using Apple's iTunes University to play and publish podcasts, but its not quite ready yet. We're setting up a few classrooms where you'll have a really simple method to record voice and publish your recording. We're trying to automate every step we can. For now, we'll look at the process if you want to creat a podcast with "more to it."
To get a feel for the end result, try subscribing to a very short podcast available to you as a sample. Some of the information on the rest of this page is about how these are created.
To do this, connect to: http://podcast.assumption.edu/weblog/
Click on Bob Fry's Weblog.
You should see a list of entries. The snapshot at right shows 3, but these will change over time. These are episodes of a podcast. The idea is that if you subscribe, then an entry will be placed in iTunes with 3 sub-entries, one for each episode. The most recent entry is normally downloaded when you subscribe. For the others, if you click the Get button next to any of these in iTunes, that item will be downloaded and can be played.
Each of the 3 items listed on this page is a podcast file. They can be in quite a few formats. The mp3 format is a very commonly used system for encoding/compressing sound. It is very basic and available for all computers. But we'll use a couple of other formats below. This relates to the different types of podcasts discussed there.
In this particular example, the first and third entries are simple short test files between 20 and 30 secondes long. The midle entry is a poetry reading that is about 6 minutes long. It is a regular mp3 file.
To subscribe to this, click Podcast as circled in the image at right. Your computer should automatically load the aggregator iTunes and set up the link feed to this podcast and download the top entry. Go ahead and try it. In iTunes play the podcasts
As far as we're concerned for now, there are 3 types of podcasts: basic, enhanced, and video. Basic is the sound only. Enhanced podcasts include an index of sections or chapters and can include a graphic for each section and can include URL's for each section so a user can follow along hearing the podcast and clicking on the links to see corresponding web materials to support or enhance the podcast. Video podcasts show video you've produced in a video editing suite (like Avid, iMovie, or Final Cut Pro). In this seminar, we'll have you make an enhanced podcast. If you can do that, you can do basic ones. We'll show a video podcast, but creating one gets beyond our time.
Creating Basic Podcasts
Almost any audio file can be used for a podcast. In some classrooms there will be small computers with brief instructions to record a class and to upload it. You can also post any mp3 file directly as a podcast. (See the IT Hub at x7060 for help converting any file to mp3).
Alternatively, you can use an iPod with a recording attachment ro record a class and then publish the content. A separate web page describes this process.
For Windows users, a program entitled Audacity can be used to record and edit audio files that are then converted to mp3 using an add-on program called Lame. Both Audacity and Lame are free.
Creating an Enhanced Podcast
Enhanced podcasts can have graphics and links. Two methods are currently available for creating and editing enhanced podcasts. One is ProfCast in which you prepare a PowerPoint presentation before a class (or presentation) and then as the presentation is given, you record the presenters voice. The program creates an enhanced podcast file with this content.
A second method is to use Garage Band. This program can be used to record or to use/edit content content recorded elesewhere.
We'll use Garage Band to mix audio in multiple tracks (very much like is done in Avid), and add still images. Garage Band is designed to be used to compose music, record from instruments or voice, edit music, mix musical tracks, and add still images. It comes with lots of musical content built in that you can use. You can also use it to record voice. Many of the computers in IT 223 have microphones built into them or attached.. You will use these to record voice content (yourself -- or anyone you do the recording).
Garage Band also allows us to use still images that are stored in the image organizing program called iPhoto. We'll go through how to get images into iPhoto in a section below including importing ordinary jpeg or gif images into it.
When you load the program, you'll get the menu at right. Click New Podcast Episode.
To give you an idea of what you'll create in this program, below is a screenshot from Garage Band of a finished podcast called Sample Cast in the content you subscribed to. The upper pane shows 5 tracks (only 4 are used). The right side shows the imagesa that will show as the podcaswt is played. The lower section lists these images. They are now what is called markers. They can be used to mark sections or chapters of the podcast. In iTunes you can jump directly to any of these (more about this later). The Male Narrator track below has a simple test voice recording in it while Jingles and Radio Sounds have musical content from Garage Band's library. Note the Male Narrator and the Jingles trach have a rubber-banded audio track below them just as in Avid to control volume.
So here are some steps to build a simple podcast. When you load the program as above to build a new podcast episode, Garage Band sets up 5 basic tracks as illustrated below. You can add content to these in any order. Before we start building our episode, lets explore file types used in Garage Band. As with several other multimedia programs we've used, Garage Band has its own proprietary format for its own files. This format ends with the extension "band" It is not readable by any other program. You should save often in case something gets cofused as in other programs. When we finish our work on our podcast episode, we'll export a podcast. This file is in a generic format called m4a. It is the audio component of the newly emerging standard MPEG-4. It is an upgrade to the old mp3 format which is the audio component format for MPEG-1. That one is quite old now, but still in heavy use.
If you would like, you can delete any track you do not intend to use. For example, if you are female, you might want to delete the Male Narrator track or vice-versa. To do this, click on the track in the first column (called Tracks) and then pull down Track -> Delete Track.
Often, you'll start with your voice recording. This way you can time and adjust background music and image markers to key points in the recording (or use none of these). You can record multiple sections sequentially. To experiment, find a short news article to read or a poem or compose your own dialog. In the illustration below, we show the setup for a male narrator. Click the button below the track name (circled in red) to indicate you will record in this track. Check the track volume to the right (circled in green) is roughly as the displayed setting. In the lower right of this pane, check the master volume (circled in orange) is near that shown.
Talk into the microphone -- even if you don't see it, its in or on the screen. Look for the audio level sliders above the green circle below to move up and down. If they do, you are ready to record. IF they don't, ask for help, call the IT Hub, or go to a page about checking the audio control panel settings.
To record, click the big red button circled in blue above. When you've said your piece (or peace), click it again to stop. You will see the current time indicator (CTI) move to the right. You can drag this back and play the track to see how it sounds. (Use the controls to the right of the record button to contol playing, or just hit spacebar to start and stop. So you just need to add some "fluff" and post!
This is the fun in Garage Band but may not be appropriate for class recordings.. Garage Band is a flexible, robust sound editing system. This page only touches the surface by walking you through adding two sound tracks. You are encouraged to begin by pulling down under Help to Garage Band Help and then in the upper right corner, click the link entitled "What is Garage Band?" For a quite thorough introduction, go to Help -> Garage Band Getting Started.
For a bit of the idea we'll explore adding content into a couple of tracks. In the illustration below, a "loop" that came with Garage Band has been added to the Jingles track. To do this, first click the button below the tracks (circled in blue) to Open Loop Browser in the lower section. This gives a listing by main and sub catagrories of built in sounds. We chose Jingles, then Orchestral, then the loop named Alliance. Then we dragged this title into the track above. You can slide the track left or right to adjust when it begins relative to the other track.
Circlide in orange, are "ducking" controls. Ducking stands for setting one track to lower its volume when another track has content. This is controlled by an up and a down arrow to the right of each track name. Up meansthe "dominant" track (as in -- the narrator). Down means background (as in the track containing the Alliance loop of music). Once you've added enogh to this track to ahve it extend beyond the anrration track, you'll notice how this works. When you play your piece, the background music will become louder when the narration ends. To see the effect, we added (by dragging it up) the Laureate loop to the track.
Circled in right is a button with an i for expanded track info to the right or below. Clicking the button to the right of this turns on or off the Media Browser that lets you select sound files from iTunes or graphics from iPhoto (or movies from iMovie).
Cirecled in green is one of three buttons to control the display of loops in the Media Browser. Try the other two views.
Adjusting volumes for mixing
In addition to the built-in ducking system discussed above, you can get a volume curve, set keyframes, and adjust volumes in a track (as in Avid). In our example, we did this to "smooth" the transition between the two audio loops we'd added. To access the audio level line and controls, click the triangle in the track (circled in red). Click on the level line to add keyframes. Drag these points down to lower volume and up to raise the volume. Another related control is a master volume level line. To see and adjust it, pull down under Track -> Show Master Track.
Importing other audio
Garage Band can use most types of audio files. Just locate any, say mp3, file and drag it into the garage band clear area under the existing tracks. A new track will be created with your mucic content.
iPhoto - pictures
Images are an important enhancement to podcasts. Unfortunately, these cannot just be dragged in like sound files. You'll need to import these from iPhoto. This program is quite a lot like iTunes. It is easy and a very powerful graphics program. It is particularly easy to use for what we will do. We'll walk through a scenario where you've got some images in folder named "pics" that are from digital pictures and other sources. You want to use them in your podcast. Here are the steps:
1. Load iPhoto. The example to the right shows the program assuming you have no images in it yet. If you already have some, they would be displayed as the ones we'll see later.
2. Pull down File -> Import to Library ... Choose your folder (we use pics). Click the Import Button. All the images will be brought into iPhoto.
3. You'll see them displayed. You are done with iPhoto. Pull down File -> Quit. hat was pretty painless, but revealed little of the power of iPhoto.
Back to Garage Band -- Enterring Images into your Podcast from iPhoto
In Garage Band, back on your file, if you click below the tracks on the right side on the button circled below in green, the panel to the right will display the Media Browser. This browser is designed to list and show icons for media available to you. Click the Photos tab as circled in red below. There are the iPhoto images including the ones you just imported.
Now just drag the pictures you want to use, one at a time into the top track named Podcast. You can move them left or right to adjust timing. Each image has a rectangle for the time in which it will show as the sequence plays. The beginning of each shows a yellow diamond at its upper left. This is called a marker. This marks the beginning of a chapter. To see what's going on click the Track Editor button (circled in blue) below the tracks to get the display of the Podcast Track content in the lower window. Note that in the Chapter Title (circled in red), you can name each chapter (or photo). When the episode is played later by someone in iTunes, they'll get a menu of chapters and can jump to any one of them. Two columns to the right of these titles for each chapter, you can enter a URL. If someone clicks the image while playing your podcast on that chapter, a browser will open and go to that URL. The podcast will continue to play. Thus you can set up your podcast as a commentary on pretty much any web content. This is a very powerful use of multimedia!
Set up a couple of your own podcasts. use different images and effects and URL's. You'll quickly see how intuitive this system is. Finally, though, we need to export and post our episode. These steps are easy.
Export your Podcast Episode
Make sure you save your .band file now so you can do any follow-up editing later that you desire. To export your finished podcast file , pull down Share -> Export as Podcast ... Name your file (for example, you might use demo.m4a). That's it. If you pull down under Share and find that Export as Podcast isn't listed and instead, it says Export to iWeb, the preferences settings in Garage Band have been messed up. Pull down under Garage Band-> Preferences ... then click Export. Look for the control called Publish Podcast and set it to Save to Disk. Then cloes that window and the Sharew will work. Now Quit Garage Band.
Load a web browser. Connect to http://podcast.assumption.edu/weblog
You'll see a page of podcasts. You'll have your own assigned account for the seminar.. Connect to it. (For example, if you are using Test3, click the Test3 Welog button.) Click the Login button lower right as circled in red. The Login Information box pictured below will open. Login using your own info. (We'll tell you.)
The menu on the bottom right will change to that shown. To post an Episode, click New Entry (circled above).
A dialog appears to enter information about your podcast episode. Enter a Title and a description and then click the Advanced button circled in red.
A podcast line appears and you should then click the Choose File button circled below in red and select your file (ex: demo.m4a) . Then click the Save button in the lower right and wait while your episode posts. If the podcast episode is long, this may take quite a while.
It is important to note that you can post any m4a file or any mp3 file as an episode. So you don't need to use Garage Band at all if all you want is to post an mp3 straight audio file wihout images. We use Garage band to add images, chapters, record, and mix sounds. But you could post an mp3 from a Windows computer and never go near Garage Band or a mac at all.
Eventually you return to your main weblog page and will see the entry as an episode. Any new episodes will be added to this. Congratulations! You've published your podcast. To check it out, click the Podcast button in the lower right (circled in red). As in our exploring on the beginning of this page, the computer will shift to iTunes and download your podcast episode.
iTunes -- Chck out your podcast and everyone else's
Finally, its time to see how the world will use your podcast. In iTunes, once subscribed you should see your podcast and each episode listed. For example, below you see Bob Fry's podcast with 2 episodes (Sampe Cast and Garvery Poem). If you are in a different area of iTunes, click Podcasts (circled in blue) on the upper left. If you have recently posted to weblog, you may need to have itunes look for updates. Click the Update icon (circled in green).
To play a podcast episode, double click its name (if it hasn't been downloaded, you'll need to click a Get button next to it.) If the episode has chapters, a pop-up of the chapters appears (circled in red). You can choose a chapter and jump to it. The graphics for the chapter will appear in the lower left of the window. If a chapter has a URL associated with it, it will show on the graphic.
Page created and by Bob Fry April 2006
Last Edited 24 July 06