Section 9.2. The Dimensions of an iMovie Photo

9.2. The Dimensions of an iMovie Photo

On the iMovie discussion forums of the Web, the question comes up over and over again: "What resolution should my iMovie-bound photos be?"

Now, technically, images 640 pixels wide and 480 pixels tall ought to be perfect for standard TV, because that's the resolution of a standard TV screen.

But you'll soon find out that iMovie has some funny ideas about fitting photos into its "frame." If you import a 640 x 480 photo into iMovie, you'll wind up with black bars on either side! (Figure 9-4 shows the idea.)

Figure 9-4. If the dimensions of your graphic aren't in the exact width-to-height ratio that iMovie demands, you'll get letterboxed bars like these.
Top: A portrait-orientation photo, flanked by "pillarbox" bars.
Bottom: A landscape-orientation photo that's not quite the right aspect ratio. Above and below: letterbox bars.

This anomaly becomes especially annoying when you intend to design a graphic from scratcha title card that you intend to dress up in a graphics program, for example. How are you supposed to know what dimensions to give it so that it will perfectly fit your iMovie frame?

You might assume that you could just design your graphics so they match the size of the video frame, which you can find out from this table:

Table 9-1. Actual iMovie Frame Sizes

Project Video Format	Screen Dimensions, in Pixels
MPEG-4	640 x 480
Standard DV	720 x 528
DV Widescreen	869 x 480
HDV (720p)	1280 x 720
HDV (1080i)	1440 x 1080

But you'd be wrong. You'd still wind up with black bars on two sides of the photo, thanks to iMovie's New Math.

So how do you make sure a photo fits exactly? You have two choices. First, you can magnify it slightly, using the Ken Burns effect (described next ), until it fills the frame and no longer displays black bars.

Second, you can crop the photo ahead of time, using iPhoto or another graphics program, so that it comes in with the oddball proportions iMovie expects.

The following table is a gold mine of useful information:

• The Ken Burns Magnification column tells you how much to magnify (zoom into) a photo to eliminate those black bars. For example, to make a standard-size photo fit the standard DV screen, you have to drag the Ken Burns Size slider to 1.03 (!).

• The iPhoto Crop column shows how to pre-crop an image so that it will fit the iMovie frame perfectly. Now, iPhoto doesn't give you any way to specify pixel dimensionsonly height-by-width proportions . (Use the Crop tool in Edit mode. From the Constrain pop-up menu, choose Custom, and type in these proportions before you do the cropping.)

• The Minimum Dimensions column shows, in pixels, the lowest resolution graphic you should feed iMovie to fit the screen neatly. Use it if you plan to pre-crop the photo in, for example, Photoshop.

Table 9-2. NTSC Projects (North America, Japan)

Project Format	Ken Burns Magnification	iPhoto Crop Proportions	Minimum Graphics Dimensions
MPEG-4	1.00	4:3	640 x 480
Standard DV	1.03	1.364:1	720 x 528
DV Widescreen	1.37	1.818:1	874 x 480
HDV (720p)	1.33	16:9	1280 x 720
HDV (1080i)	1.33	16:9	1920 x 1080

Table 9-3. PAL-Format Projects (Europe)

Project Format	Ken Burns Magnification	iPhoto Crop Proportions	Minimum Graphics Dimensions
MPEG-4	1.00	4:3	640 x 480
Standard DV	1.03	1.364:1	788 x 576
DV Widescreen	1.37	1.822:1	1050 x 576
HDV (720p)	1.33	16:9	1280 x 720
HDV (1080i)	1.33	16:9	1920 x 1080

* (If you plan to use the Ken Burns effect, of course, you'll want to use much greater resolution to avoid ugly pixellationtwice the listed resolution, for example, for a 2X zoom effect.).