Home > Articles > Graphics & Web Design > Dreamweaver & Flash

This chapter is from the book

Planning the Projects

Almost all the work for these projects is done in the preproduction stage. If you do a good job preparing everything, the projects will go more smoothly than a television cooking show (where everything is measured and chopped up in advance). The preparation here involves gathering the transcript of the captions that will appear and identifying the places at which those captions should appear.

After you have your captions prepared, you’ll move on to creating a few text display templates. On the surface, this is nothing more than selecting a variety of fonts to use; however, you’ll also add an animation effect for when the text changes. The text display templates you create can be used with any future project you build where you want captions. The rest of the chapter shows you how to implement the support class I built called EventChannel. It handles all the grunt work of reading in the captions and making them appear in synch with your audio or video.

I should note that captions are good for much more than simply displaying the movie’s dialogue for hearing-impaired folks (although captions obviously do that well, too). I’ve used the techniques from this chapter to display captions in multiple languages for a museum kiosk. I’ve also used the techniques in this chapter to display the lyrics for music where the singer might not annunciate the words clearly. The projects you build in this chapter can apply to any situation in which you want something to appear (such as text) in synch with your audio or video.

Cue Points and Captions

There’s one huge chore when captioning audio or video: transcribing—someone needs to type in all the text. Plus, that text needs to be segmented into blocks that both fit within a given screen space and match the tempo of the video. Preparing a transcript for cue points is nothing more than creating a text file with every block of text on its own line, as in this example:

There once was a man who loved a woman.
She was the one he ate that apple for.
and so on...

You simply want to make sure that each line fits in the space you’re allotting for the captions and that, when synched with the audio, the captions appear on screen long enough to read. For example, if you have space for only one or two words to appear at a time, they’d have to fly by so fast no one could read them.

The final step of synchronizing the captions with the media goes very quickly after you have the transcript prepared. With the tools I built for this chapter, you’ll see that you can identify cue points in real time while watching the video. All the investments you make to prepare the captions will make this otherwise tedious process go smoothly.

Cue Point Types

There are no fewer than five types of video cue points: Event, Navigation, ActionScript, Caption, and Marker. Although each has its respective benefits depending on your application, they’re mostly equivalent. The idea of any cue point is the same: to associate a block of information you want to appear—or, at least, get sent to your application—at a specific time in the video. Generally, the exact content for a cue point is whatever you decide. However, the exact form and where the cue point information resides are what vary in the different cue point types.

Videos produced in Flash Professional 8 (or the accompanying Flash Video Encoder) can be permanently injected with Event or Navigation cue points. The difference with Navigation cue points is that they are seekable (unlike Event cue points). That is, the Encoder places a keyframe in the video at the exact frame you place a Navigation cue point. This way, users can navigate directly to such keyframes by clicking the Next or Previous button in the FLVPlayback component shown in Figure 3.1 (which triggers the seekToNextNavCuePoint() and seekToPrevNavCuePoint() methods). You can find the FLVPlayback component by selecting Window, Components.

Figure 3.1

Figure 3.1 The FLVPlayback component lets the user seek to the next or previous Navigation type cue point.

ActionScript cue points aren’t permanently embedded into the FLV, which makes them different from all the other types of cue points. I’ll talk about the advantages or disadvantages of this approach in the next section. For now, just realize that ActionScript cue points are set at runtime; therefore, they require additional scripting before the video starts. (As an added bonus, the project "Implement Code for Audio-only Captions" shows you how to use ActionScript cue points with an audio source instead of a video source.)

Each of these three Macromedia cue point types (Event, Navigation, and ActionScript) have properties for time and name. The time corresponds to where the cue point appears in the video, and the name is an arbitrary string you specify. You can include any text you want, such as a caption or a description of what’s happening onscreen. Plus, each cue point has room for additional parameters—namely, as many name/value pairs as you want. In this way, you can associate more than just a single line of text with a particular cue point. For example, you could store captions in different languages such as the following name/value pairs:

name:value
en:"Hello Friends"
es:"Hola Amigos"
fr:"bonjour amis"

Remember that you’re packing information into a moment in time; you can store just a name or as many other parameters as you want.

Finally, although the third-party product Captionate (shown in Figure 3.2) is needed to inject Caption and Marker cue points, these cue point types are definitely worth including in this list. Captionate Markers are simple: They’re just text labels associated with a moment in time. However, Captionate Captions are similar to Macromedia cue points because they have room for additional, optional information (in addition to the caption itself). Captionate Captions also let you identify a speaker (that is, the person talking) with each caption.

Figure 3.2

Figure 3.2 The Captionate interface lets you inject captions and markers.

In fact, Captionate’s Caption type of cue point supports multiple tracks for multilingual applications. You could probably squeeze this same kind of information into the Macromedia cue point format (Event, Navigation, or ActionScript), but the logical and convenient structure is already built in to the Captionate Caption cue point. (If nothing else, you’ll want to get Captionate because it lets you modify any cue points—including Macromedia ones—embedded in the .flv file; otherwise, these are uneditable.)

You can use any or all of these cue point types in a single video. You can also write code that responds to each type differently, perhaps displaying Caption cue points in a text field and then using Event cue points to jump to a different frame in a movie clip. Instead of learning the different syntaxes to handle all the cue point types, the projects in this chapter channel all the cue points through a single clearinghouse: the EventChannel class. This class triggers events in your project for every cue point type you want to listen for.

Embedded Cue Points Versus Separate Text Files

One of the coolest features in Flash Professional 8 is that, during the video encoding stage, you can embed cue points right into the video. As great as this feature is, though, it does have some disadvantages.

The biggest problem with embedding cue points into the video is that they’re uneditable after the .flv file is encoded. (Well, the excellent third-party application called Captionate does let you edit cue points.) Although embedded cue points might be convenient because the data and video stay together, the data isn’t left open for easy access. The alternative is to keep all the details of your cue points in an external source, such as an XML text file.

Saving cue point information in XML (a separate file from your video) can have its advantages. For example, if you have the same video encoded for different bandwidths, you can use a single XML file for the cue points. After all, the captions are the same for each bandwidth, so making an edit involves just one file instead of each .flv file. Plus, as you’ll see in the tool I built for adding cue points, there are more convenient ways to specify cue points than through the Flash video encoder’s interface. For one thing, when specifying cue points in Flash, you can’t hear the audio track, which makes finding cue points very difficult indeed.

As great as storing cue point information in separate files is, if you choose that approach, you have to perform the additional step of importing and parsing the data. Also, although the FLVPlayback component has an addASCuePoint() method (to inject ActionScript cue points at runtime), you’re pretty much taking a home-grown approach that might not match other developers’ ways of working. I should note that, even though the only logical format for an external file containing cue point information is XML, the exact structure of that file (that is, its schema) is up to you. As long as you leave room for all the cue point types, the exact schema is completely subjective. However, for this project to work, you have to use a single format. The structure I’m using is based on the output from Captionate—which, I suppose, makes this format "better" only because it’s consistent with another product.

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.

Overview


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information


To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information


Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children


This site is not directed to children under the age of 13.

Marketing


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information


If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information


Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents


California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure


Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact


Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice


We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020