Flash CS4 Professional in 24 Hours- P9 doc

Import a Sound TRY IT YOURSELF ▼ The process of impor ting sounds into Flash is simple.. Conversely, say you want to hear a smack sound effect every time aball bounces on the ground.. Ef

Rights Management (DRM) technology that make them difficult or

impos-sible to copy Some CDs don’t even play in your CD player

Fortunately, you can usually use sound in your animation without

worry-ing about all these details, as you see in the next task

Import a Sound

TRY IT YOURSELF ▼

The process of impor ting sounds into Flash is simple Follow these steps:

1 In a new file, select File, Import, Import to Library, and then select an

audio file to impor t In Windows, you are likely to find a few WAV files

in the folder C:\Windows\Media or My Documents\My Music, or you

can search for *.wav and *.mp3; Macintosh (Mac) users can use Find

for Files of Type: Sound You can filter the files shown in the Impor t

di-alog box by setting the Files of Type drop-down list to All Sound

For-mats, as shown in Figure 13.1 If you simply can’t find any audio files,

you can download some from the publisher’s website

2 After you select an audio file and click OK in the Impor t dialog box,

you don’t see anything on the Stage or Timeline However, the sound

has been impor ted and now resides in the Library Open the Library

window by pressing Ctrl+L to see it Now that the movie contains the

sound file, you can use the sound

3 Although we’re not covering how to use sounds in depth until the next

section, it’s easy There are two basic ways to use the sound in a

Using SoundsNow that you’ve imported sounds into a movie, you need to make themplay at the correct time Without using ActionScript, the one place you canuse sounds in Flash is in keyframes With ActionScript, you can add soundsdynamically by using the Sound object, for which we provide the startercode after this hour’s “Summary” section If you want a sound to playwhenever the user places his or her cursor over a button, you still need toplace the sound in a keyframe; it’s just a keyframe in the button (Neverfear, we get to buttons in Hour 16, “Basic Interactivity.”)

cur-in the Proper ties panel, select the sound you impor ted from the down list, as shown in Figure 13.2 This list displays all the soundspreviously impor ted into the movie In our example, we impor t a soundnamed Ooooh.wav

drop-4 Test the movie, and you should hear the sound Of course, your puter speakers and sound card must be functioning

com-FIGURE 13.2

When a keyframe is selected, the

impor ted sound appears in both

the Librar y and the Proper ties

panel.

Knowing that sounds go in keyframes is fine, but you need a way to put

them there When you select a keyframe, the Properties panel provides a

way to control what sounds play when you reach the selected keyframe

Flash provides other clues for you to see where sounds have been placed

For example, if your Timeline is long enough, you see a waveform or a

vi-sual representation of a sound for the sound being used, as shown in

Figure 13.3

FIGURE 13.3

The waveform is displayed in the Timeline This is helpful when you’re tr ying to synchronize images with specific par ts of sound.

Using the Properties panel is the best way to see which sounds have been

added to which keyframes Like any other panel, the Properties panel

dis-plays only the sound used in the selected keyframe Misreading this panel is

easy because it changes when you deselect keyframes Figure 13.4 looks

al-most identical to Figure 13.3 However, in Figure 13.4, the Properties panel

shows no sound is being used When you look closely at the Timeline, you

see a waveform is displayed, but no keyframe is selected Therefore, it’s

necessary to look at the Properties panel after you’ve selected a particular

keyframe

Sync Settings

When you have the Properties panel reflecting sound for the intended

keyframe, you can decide exactly how the sound should play The most

fundamental choice you need to make is the Sync setting This controls

ex-actly how a particular instance of the sound plays or, more specifically, the

priority of the sound compared to the visual elements in the animation

FIGURE 13.5

For each instance of a sound, you

must select a Sync setting via the

Proper ties panel.

FIGURE 13.4

The Proper ties panel can be

con-fusing; it only displays or enables

you to specify sounds when a

keyframe is currently selected The

keyframe isn’t currently selected,

so the Proper ties panel displays

nothing.

more slowly or quickly because that would make them sound odd,

but a machine with slower graphics performance might take longer to

display visual elements Suppose you have a 1-second sound set to

Event, and your frame rate is 12 fps You would expect that during

the sound, 12 frames would be displayed, but a slow machine might

display only 6 fps during that 1 second In either case, the sound

fin-ishes 1 second later, as you would expect, but the number of frames

displayed can vary

Start—This setting is almost the same as Event, except that multiple

instances of the same sound are prevented With Event, a sound can

be layered on top of itself, similar to singing a round Start, on the

other hand, plays a sound if it’s not already playing

Stop—This setting is for when you want a specified sound to stop

playing Say you import a sound called Background Music, and make

it start playing in the first keyframe of one layer Then, you import

another sound called Narration and make it start playing in the first

keyframe of another layer In Frame 10, you place another keyframe

with the same sound (Background Music) set to Stop, so that sound

stops Both sounds start at the beginning, but on Frame 10 the

back-ground music stops and the narration continues to play This is a bit

strange because normally you use the Properties panel to specify the

sound you want to play where here you specify the sound you don’t

want to play Think of Stop as “Stop this sound if it’s playing.”

Stream—This setting causes the sound to remain perfectly

synchro-nized with the Timeline Because you can’t have sounds playing

slowly if the user’s machine can’t draw frames quickly enough, this

setting forces Flash to skip frames to keep up Stream sounds start

playing when the keyframe is reached and continue to play as long as

space is available in the Timeline In other words, if your sound is 3

seconds long and you’re playing at 12 fps, the Timeline has to be at

least 36 frames; otherwise, part of the sound is never reached You can

compare the Stream setting to a Graphic Symbol’s behavior The

ben-efit of the Stream setting is the synchronization is always the same If

in this case you place a graphic in Frame 12, it coincides perfectly

with the first second of your sound Remember when you’re using

Stream, you have to ensure enough frames are in the Timeline to

ac-commodate the length of the sound Finally, you preview Stream

sounds as you scrub, thus making the process of synchronizing audio

to images possible

The decision as to which Sync setting to use isn’t terribly difficult Event

should be used for any short incidental sounds, such as rollover sounds We

suggest Event for all sounds that don’t require critical synchronization

Background music that plays and loops doesn’t need to be synchronized,

so you should use Event for it Start is a perfectly good alternative to Eventbecause it’s the same, but it prevents the same sound from layering on it-self For example, suppose you have a row of five buttons If each buttonhas the same rollover sound and the user quickly moves across all five, anEvent sound plays once for each button If the sounds are short enough,this is probably appropriate However, if the sounds are quite long, they be-come discordant If you use the Start Sync setting, only one instance of thesound plays at a time, regardless of how fast the user moves his or hermouse Event can be a better choice than Start when a little bit of overlap isokay Conversely, say you want to hear a smack sound effect every time aball bounces on the ground If you choose Event, you hear a smack for eachbounce, even if the ball bounces a second time before the first sound finishes

In any event, Start and Event are good for the majority of sounds you play

The Stop Sync setting is powerful It gives you a way to stop specificsounds Using this method can be a tricky because it stops only one soundper keyframe Depending on the situation, this might be appropriate Ifyou’re giving the user the ability to get several sounds at once, you want tolearn about Stop All Sounds Suppose you have one sound playing in thebackground, and when a tween starts, you want a special sound effect toplay and keep playing until the tween ends You can put the backgroundsound in an early keyframe, and then in the first keyframe of the tween,

place the sound effect and set its Sync setting to Event or Start In the last

frame of the tween, you can use the same sound effect but with the StopSync setting This way, the sound effect stops at the end of the tween, butthe background sound continues

Finally, Stream is good for one thing: synchronizing graphics with sound

This is especially useful for character animation where you want a ter’s lips to synchronize with its voice When trying to synchronize soundswith images, you can use the scrub technique; if you use Stream sounds,you can hear the sound as you scrub Because Stream sounds effectivelylock themselves to the Timeline, you probably don’t want to change themovie’s frame rate For example, a 3-second sound takes 36 frames at 12fps If you do some work and then change the frame rate to 24 fps, the same3-second sound spans 72 frames! Flash automatically spreads the Streamsound out so it takes 3 seconds when you change the frame rate, but Flashdoesn’t change your graphics, which now plays in 1.5 seconds See Figure13.6 for a before-and-after example of changing the frame rate after an ani-mation is built

charac-NOTE

Rollover Sound

Rollover is when the user places

his or her cursor over a button,

so a rollover sound is a sound

that plays when the user rolls

over a button

In spite of this issue, you should stick with a frame rate Stream sounds

re-main pretty appealing However, on slower-performing machines, frames

are skipped to make sure a stream sound stays synchronized It’s often

more important that every frame of your animation appears even if it

means the sounds might drift out of synchronization Use Stream only

when the synchronization is critical, and you don’t mind dropping frames

Otherwise, use Event or Start

Effect Settings

The Properties panel provides some fancy effects you can apply to the

vol-ume of a selected sound The drop-down list next to Effect includes effects

such as Fade In, Fade Out, Fade from Left to Right, and Fade from Right to

Left To understand and customize these settings further, you can either

se-lect Custom from the list or click the Edit button on the Properties panel to

access the Edit Envelope dialog box, which is shown in Figure 13.7

FIGURE 13.6

The same animation and sound are shown with frame rates of 18 fps (top) and 6 fps (bottom) Notice keyframes and tweening are not af- fected, but the sound uses less of the Timeline when the Timeline is advancing at 6 fps The shor t si- lence at the star t of this sound means users don’t hear anything until a few frames of the animation have played.

Left channel

Right channel Envelope lines

Stop/Play Envelope handles Zoom in/out

Display units

The Edit Envelope dialog enables you to modify the volume of the sound as it plays through the left and right channels.

Additional details for the Effect settings are

Left Channel/Right Channel—This option displays different waveforms if your original sound was stereo If you use only monosounds, you still get the left and right channels, so you can createpanning effects In the case of mono, the same sounds come out ofeach speaker, but you can modify the volume of each

Envelope lines—These indicate the volume level at any particulartime in the sound When the line is at the top, the sound plays at full100% volume Some audio tools are different because they use themiddle to indicate 100% and anything higher to indicate amplified orboosted sound, but this is not the case in Flash As the envelope line isgetting higher when you move to the right, the volume is increasing

Envelope handles—These are like keyframes within sound If youwant the envelope lines, which indicate volume, to change direction,you need to insert a handle All you need to do is click anywhere on aline, and a handle is inserted No matter which channel you click, amatching handle is placed in the other channel A handle in onechannel must match the moment in time (left to right) of the handle

in the other channel However, the volume (height) can vary betweenthe two

Time In Marker—This marker enables you to establish the startingpoint of a sound You’re effectively trimming the extra sound or si-lence at the beginning of the sound file You’re not telling the sound

to start any later, but the sound you hear begins wherever the Time Inmarker is placed

Time Out Marker—This marker enables you to trim extra sound offthe end of a sound file Often, you have a moment of silence at theend of a sound file, and even if you don’t hear anything, it adds to thefile size You can get rid of it by moving the Time Out marker to theleft You don’t actually destroy the source sound in your Library, butwhen you export the movie, the unused portions of the sound isn’tused so your file stays small

Stop/Play—This option enables you to preview all the settings you’vemade This is important because although the waveform can enableyou to visualize a sound, you ultimately want to judge the effect of asound with your ears

Zoom In/Out—This option enables you to zoom in for a close up ofthe current window to control precisely how you place the TimeIn/Out markers or envelope handles or zoom out so the entire soundfits in the current window

Display Units (Time or Frames)—This option simply changes the

units displayed in the center portion from time units (seconds) to

frame units Time is not as useful as Frames when you want to match

sound to a particular frame where something visual occurs If the

dis-play shows a peak in the music at 1 second, you have to use frame

rate to calculate exactly which frame that translates to With the

dis-play set to Frames, Flash does the calculations for you

Panning is an effect that makes sound seem to move from left to right or

right to left It’s a trick in which the volume for one channel (left or right) is

increased while the volume for the other channel is decreased When

com-bined with a graphic moving in the same direction, this technique can be

ef-fective Imagine, for example, a car moving across the screen at the same

time the audio pans in the same direction

Despite the details in the Edit Envelope dialog box, you only have two

ba-sic ways to use it: You can either use a preset effect or make your own You

can start with a preset, such as Fade In, and then make modifications to it,

essentially making a custom effect based on a preset Use the effects in any

way you think appropriate Listen to the effect after each change by clicking

the Play button Nothing you do here affects the master sound in your

Li-brary You can use the same sound several times throughout a movie with

different effects in each instance

One of the most important things to remember is the Time In and Time Out

markers can save file size Only the sounds and portions of sounds actually

used are exported when you publish a movie Unused sounds in the

Li-brary and portions trimmed from the beginning or end of a sound are not

exported Trimming a few seconds off the end of a sound can mean many

seconds, or even minutes, of download time for your users Also, changing

the volume of a sound has no impact on file size, so setting the envelope

lines to the lowest level makes no sense

Loop Settings

The Properties panel has an option that enables you to specify how many

times a sound repeats or to have the sound loop forever

Some sounds loop better than others Basically, a sound that loops well

ends the same way it starts There’s an art to making sounds loop

Al-though importing a large song and using the Time In and Time Out

mark-ers to establish a nice looping sound is possible, it isn’t easy More likely,

you have to find a sound already prepared by an audio engineer A

In this task, you add sounds to a sample movie Follow these steps:

1 Download the file keyframing.fla from the publisher’s website InFlash, open this file, and then press Enter to watch the animation

2 Open the Library for the keyframing.flafile by selecting Window,Library (or press Ctrl+L)

3 Now these sounds are available to your file, but you need to put theminto keyframes First, you need to make a new layer to contain thesounds; select Insert, Timeline, Layer Don’t worr y if Flash puts thenew layer under all the others because it doesn’t matter where it ap-pears Name this layer Background Music by double-clicking on itsname and typing the new name

4 Select the first frame of the Background Music layer, and look at theProper ties panel From the Sound drop-down list, select Visor HumLoop To make this sound loop continuously, change the drop-down listfrom Repeat to Loop, as shown in Figure 13.8

FIGURE 13.8

Flash can loop a sound

indefi-nitely with the Loop setting.

TIP

Testing Your Movie

Instead of using the Test

Movie command, you’ve

tested this movie by clicking

the Enter or Return key, and

you can’t get the sound to

stop! It’s driving you crazy To

stop the sound, choose

Control, Mute Sounds This

stops the looping sound

Then, choose Control, Mute

Sounds again to uncheck it,

so you can test it the right

way using Control, Test

Movie

5 Select Control, Test Movie The sound loops nicely, and it adds a bit

of drama to the movie In the following steps, you add some incidentalsound effects

6 Select Insert, Timeline, Layer, and name the layer Sound Effects

You’re going to inser t a sound effect when the “CS4” is rotated to the

left, which happens at Frame 14 In Frame 14 of Sound Effects, select

Insert, Timeline, Keyframe (or press F6)

7 Select the keyframe you inser ted, and from the Proper ties panel,

se-lect Smack from the Sound drop-down list Leave the default settings,

Event Sync and Repeat x 1, because you don’t want this sound to

loop

8 Select Control, Test Movie The Smack effect is good, but the

hum-ming continues throughout the whole movie

9 To stop the hum, select Frame 30 of the Background Music layer, and

select Insert, Keyframe (or press F6) Make sure you’re selecting only

this keyframe, and then use the Properties panel to inser t the Visor

Hum Loop again This time select the Stop Sync setting to cause any

instances of this sound to stop You can use Test Movie again to see

and hear the results

10 Finally, add a sound effect for when the pink sparkle animates At

Frame 30 of the Sound Effects layer, select Insert, Keyframe (or

press F6), select only this keyframe, and then inser t the Beam Scan

sound Use Test Movie, and it should be more dynamic than the silent

version By the way, these sounds only add about 3 kilobytes [KB] to

the total file size!

11 You can tr y removing the excess silence at the star t of the Beam Scan

sound Select Frame 30 in the Sound Effects layer, and click on the

Pencil button to the right of Effect on the Proper ties panel Then, you

can cut sound off the beginning by dragging the Time In marker in the

Edit Envelope dialog box (refer to Figure 13.7)

Controlling Quality and File Size

Now that you know how to incorporate sound in a movie, it’s time to talk

about optimizing it for export A direct relationship exists between quality

and file size If you want the best-quality sound, the file size grows

Con-versely, small file size means lower sound quality You ultimately need to

make a decision about how to balance this tradeoff Is a high-quality sound

important enough to make your audience sit through an extended

down-load time? Is a speedy downdown-load worth the sacrifice in quality? You should

be deliberate in your decision-making process to end up with the best

com-promise possible While exploring this topic further, we first cover some

digital audio fundamentals, and then you learn how to apply this

knowl-edge to Flash’s compression settings

Digital Audio FundamentalsEarlier this hour we suggested two sensible ways to use audio in Flash Youcan either import high-quality audio (.wavor.aif), and enable Flash tocompress it when you publish or import an MP3, which, by definition, is al-ready compressed

If you take the route of importing high-quality sounds, you want to know afew basics about .wavand.aifsounds The two primary factors that affectthe file size are sampling rate (that is, how many pieces of sound are savedper second) and bit dept, (or how much detail is saved in each of thosesamples) CDs have 44,100 samples per second (often expressed as 44K)and 16-bit depth (meaning 65,536 “shades” of sound) So, a 44K/16-bit au-dio file is good If you listen to an 8-bit sound file, it has a much lower dy-namic range (from high to low) The quality loss when you listen to fileswith a lower frequency rate (such as 22K, 11K, or lower), are not quite asobvious, but they tend to sound hollow A longer sound is bigger and stereosounds are twice the size of mono

If you want to start with MP3s, bit rate is the one factor to consider A ond MP3 file that’s 256 kilobits (Kb) has a bit rate of 256 kilobits per second(Kbps) MP3s can have bit rates up to 320Kbps It’s possible to have a vari-able bit rate (VBR) MP3 instead of a constant bit rate (CBR) MP3 A VBR isuseful because portions of the sound with more detail use a higher bit rate(up to 320Kb), while other places in the sound might not need as muchdepth A VBR MP3 often sounds better than an equivalent-sized CBR MP3because more detail is where it’s needed In fact, the average bit rate ismore important than simply the bit rate This discussion leaves out exactlyhow your audio compression tool applies the MP3 algorithm The softwarecuts out details from the sound where your ear is least likely to notice Inthe end, it’s basically magic because you’re left with a small sound file thatsounds almost as good as the original

1-sec-Back to the world of Flash, the easiest way to approach audio is to bring in

an uncompressed audio file and enable Flash to apply MP3 compressionupon publishing the.swf That is, you can bring in a.wav, and Flash inter-nally converts it to an MP3 Flash’s MP3 compression is not VBR, so it’s pos-sible to create a better sounding small MP3 file outside of Flash If youimport an MP3, Flash doesn’t recompress it unless you override the defaultsettings In the next section, you see exactly how to control Flash’s exportsettings This brief overview of digital audio should give you enough infor-mation to analyze your source audio files before you import them into Flash

NOTE

The Mystery of

the Deep Voice

Digital audio tape (DAT) uses

48K/16-bit audio On several

oc-casions, a professional audio

person supplies audio in this

for-mat, and it’s a problem in Flash

You can tell you’ve impor ted

48K audio when you play back

the movie The sounds are

slowed down, so they sound an

octave deeper They’re actually

playing slower at 44,100

sam-ples per second instead of

48,000 Flash tops out at

44,100, so you need to

resam-ple using an audio editor before

you impor t larger samples into

Flash

Export Settings

All this theory is interesting, but how do you apply it to your sounds? You

have two places in Flash where you can specify quality and compression

settings: the Sound Properties dialog box and the Flash tab of the Publish

Settings dialog box The Sound Properties dialog box affects settings that

are unique to the individual sound, and the Publish Settings dialog box

af-fects all sounds globally

Global Publish Settings

To set the default sound format for every sound in a Flash movie, you select

File, Publish Settings Make sure that under the Formats tab you’ve

checked Flash (.swf), and then click the Flash tab (see Figure 13.9)

FIGURE 13.9

The Flash tab of the Publish tings dialog box provides a way to set the default sound settings glob- ally for an entire file.

Set-You see two different sound settings in this dialog box: Audio Stream and

Audio Event Audio Stream affects sound instances that use the Stream Sync

setting, whereas Audio Event affects sounds that use the Event or Start Sync

setting (The Audio Stream setting also affects the audio from videos you

import, as you learn in Hour 18, “Using Components.”) If you click the Set

button, you can see all the options available, as shown in Figure 13.10

The Set button located next to both Stream and Event enables you to set thecompression for sounds used each way separately Sound compression pro-vides five choices With the exception of when you use Raw, which is really

no compression, you need to specify additional options for the compressionyou choose For example, you can’t say, “Compress using MP3.” You have

to specify how much MP3 compression Because each option has its ownunique characteristics, let’s look at each in detail:

ADPCM—This option is almost the same as Raw (discussed shortly),except you can optionally choose a different sample rate than youroriginal sound You usually want to lower the sample rate because in-creasing it makes the file bigger without improving the sound Youcan also convert stereo to mono ADPCM compression is coarse andnever sounds as good as an MP3 compression The only reason to usethis option rather than MP3 is when you have to deliver a movie toFlash Player 3

Disable—This option is simple It tells Flash not to export anysounds When you select Disable from the drop-down list, there are

no other options to set

MP3—This option provides great compression When exporting, ways use the Quality setting Best because it doesn’t affect the file sizebut improves quality The bit rate is simply how much data per sec-ond you’re letting the MP3 file take The higher the number, the bet-ter In theory, a bit rate of 56Kbps is maintainable on a 56Kbpsmodem; however, reality is sometimes different from theory becauseother factors can slow the download performance We explore moreissues related to downloading in Hour 22, “Minimizing File Size.”

al-You have to test this and keep lowering the bit rate until just beforethe sound becomes unacceptable You can judge the result by testingthe movie or, as you see in the next section, “Individual Export Set-tings,” you can test each sound individually

FIGURE 13.10

You can set the type of

compres-sion for all sounds in a movie in the

Publish Settings dialog box.

Raw—This option leaves your sounds intact, although you do need

to specify a sample rate Frequency rate Raw is useful while you’re

testing because you don’t have to sit through the time Flash takes to

compress your sounds every time you use Test Movie Remember to

set it back later, or your files are huge

Speech Compression—This setting is optimized for the human voice

In practice, however, you should always compare the quality and file

size effects of speech compression to MP3 because the best choice

varies case-by-case

You’ve learned how to set the default sound settings for both Stream and

Event sounds from the Publish Settings dialog box It’s important to

under-stand the default publish setting affects only uncompressed (that is,

non-MP3) sounds you’ve imported You see in the next section how to set sound

settings for each imported sound individually Imported uncompressed

sounds (.aifand.wav), by default, use the settings you make in the

Pub-lish settings Imported compressed sounds (MP3) don’t recompress and,

therefore, don’t follow the Publish settings One exception is when you

se-lect the Override Sound Settings check box in the Publish settings

Check-ing this box causes the settCheck-ings you apply here to impose on all sounds in

the movie, regardless of their individual export settings Override Sound

Settings can be useful when you want to publish a single copy for a special

purpose Say you want a copy to demonstrate from your hard drive

Down-load time isn’t an issue, so you could make all the sounds play at their

highest quality (Raw)

Individual Export Settings

In addition to a movie’s globally specified sound settings, each sound item

in the Library can have its own individual settings, which applies to every

instance of that sound Double-click a sound in the Library (or select

Prop-ertiesfrom the Library’s option menu), and you see the Sound Properties

dialog box, as shown in Figure 13.11

This dialog box is similar to the Bitmap Properties dialog box you studied

in Hour 3 In the same way that individual imported bitmaps can have

their own sets of compression settings, so, too, can imported audio The

choice of settings is identical to the settings in the Publish Settings dialog

box However, in this dialog box, for each change you make, you’re given

details of the effect on file size and quality Under the Compression