Adobe 22030000 User Guide - Page 40

ENCORE CS3 36 User Guide High-definition video and still images have either square 1:1 pixel aspect ratios or a 1.333 anamorphic pixel aspect ratio. They come in three sizes (1280 x 720 or 1920 x 1080 with square aspect ratios, and 1440 x 1080 pixels with anamorphic aspect ratios), and fit in a 16:9 screen aspect ratio. Screen aspect ratios Screen aspect ratios (also known as frame aspect ratios) describe the width-to-height ratio of an image or device. A standard television has a 4:3 ratio (referred to as fullscreen) and a widescreen television has a 16:9 ratio. These ratios are also noted as 1.33 for fullscreen (4 / 3 = 1.33) and 1.78 for widescreen. (Film, which comprises a majority of widescreen content, actually uses screen aspect ratios ranging from 1.66 to 1.85, or even 2.35 for scope footage-but these all work well within the format and can be considered widescreen.) The screen aspect ratio is determined by two factors: the resolution of the image and the size of the pixels within it, or the pixel aspect ratio. As the resolution for a given asset is constant, (for example 720 x 480), Encore sets screen aspect ratios based on the asset's pixel aspect ratio. About still-image pixels Most digital still cameras and graphic applications use square pixels. You should set the pixel aspect ratio of stillimage assets to square to ensure that they display correctly. An exception to this rule are files created in Adobe Photoshop CS and Adobe Photoshop CS2. Photoshop lets you work in nonsquare pixels when creating images for DVDs and video. Use the Photoshop preset that matches your project. For example, if you're working with NTSC DV footage at 720 x 480, you'd use the NTSC DV 720 x 480 (With Guides) preset. Specify an asset's pixel aspect ratio You can mix assets with different pixel aspect ratios in the same project. Encore interprets each asset's pixel aspect ratio on import. Occasionally, an asset may contain incorrect information which, in turn, prevents Encore from identifying it correctly. If you need to change an asset's pixel aspect ratio, you can use the Interpret Footage command to specify it. Changing the pixel aspect ratio for a video asset used in a timeline changes that timeline's screen aspect ratio. To change the screen aspect ratio for a still timeline, see "Specify the screen aspect ratio" on page 37. 1 Select the file in the Project panel. 2 Choose File > Interpret Footage. 3 In the Interpret Footage dialog box, select Conform To, and then choose the appropriate pixel aspect ratio: • Square Pixels (1.0) for a standard-definition or high-definition file created using square pixels. • SD NTSC (0.9) or SD PAL (1.066) for a standard-definition file created using nonsquare pixels with an aspect ratio of 0.9 (NTSC) or 1.0667 (PAL). • SD NTSC Widescreen (1.2) or SD PAL Widescreen (1.422) for a standard-definition file created using nonsquare pixels with an aspect ratio of 1.2 (NTSC) or 1.422 (PAL). • HD Anamorphic (1.333) for a high-definition file created using nonsquare pixels with an aspect ratio of 1.333. 4 Click OK.