Section 22. Prepare a Still for Video

22. Prepare a Still for Video

BEFORE YOU BEGIN

14 Add Media with the Adobe Media Downloader

21 Grab a Still from Video

SEE ALSO

16 Create and Use Media Folders

23 Scale and Position a Still

24 Set a Still Image Duration

70 Pan and Zoom Still Images a la Ken Burns

Although they share many basic features, a digitized photo and digitized video are two very different media. Although Premiere Elements does its best to render your photo into a video format, an improperly prepared photo can often produce some unfortunate results in your project, and photos with unnecessarily high resolution can cause extremely long rendering times and even complete system lockups.

Premiere Elements accepts a wide variety of graphics file formats including TIFs, BMPs, JPGs, PNGs, GIFs, PDFs, EPSs, and even native Photoshop (PSD) and PhotoDeluxe (PDD) files. Your choice of graphic format will often be a matter of convenience. However, there are definite advantages (and disadvantages) to each format type.

There are two prime considerations when selecting a format for your graphic. First, consider the amount and type of compression the file format uses. JPEGs, for instance, are relatively small graphics files. However, they also use a compression system that, at higher levels, can actually change or even damage the details of your graphic. Whether the effect this type of compression has on your file is at an acceptable level and worth the trade-off for a smaller file depends on your personal feelings and how you plan to ultimately use this graphic.

22. Prepare a Still for Video

The second consideration in selecting the ideal format for your graphic has to do with the file's capability to carry an alpha channel. Alpha channels can be a powerful aspect of your graphics workflow, as you can see in 94 Frame Your Video with an Image.

Tagged Image Format (TIF or TIFF) files are one of the most commonly used image formats. Because they are relatively uncompressed, they are the preferred format of professional designers. A TIF can be opened, modified, and resaved indefinitely without any loss or damage to the image data (unlike more compressed file formats such as JPEGs), and they are far and away the most hardy digital image format in use today.

An added advantage of TIFs is that they can also save layers of images. This means that if you've created an image sized or shaped differently than your canvas in Photoshop Elements and you leave your background layer blank, your image is displayed in Premiere Elements with the transparent background carried as an alpha channel, displaying as transparent in Premiere Elements. (Technically, this is because Premiere Elements reads the transparent areas as an alpha channel. See 94 Frame Your Video with an Image.)

The PSD format is a native Photoshop file. PSD files can be imported into Premiere Elements with their alpha channels, or transparent areas, displayed as transparent. Additionally, Premiere Elements and Photoshop Elements are designed to work hand in hand; for a variety of reasons, PSD is an ideal format for bringing Photoshop and Photoshop Elements graphics into Premiere Elements.

Bitmap (BMP) is an older file format created by Microsoft in the early days of personal computers. Although BMPs are not the most efficient size-wise, they are a perfectly acceptable graphics format in which to save your video graphics.

Named for the Joint Photographic Experts Group, JPGs (also known as JPEGs) are perhaps the most common graphics format used by consumers. Most digital still cameras save their photos as JPEGs because the format allows for a high compression of the image data and a much smaller file size than TIFs. Unfortunately, the smaller file size comes with a price. Repeated saving of JPEGs, especially at higher compression levels, can damage the image data, resulting in corrupted pixels, particularly in the finer details of your photo and at color breaks.

In most cases, however, a first-or second-generation JPEG file is perfectly acceptable for your videothe exception being in situations in which the finer details of your graphic are going to be scrutinized (as when you're applying a major scaling effect), when you are planning to use the Chromakey effect on your photo, or you are applying a color substitution. Because JPEGs use a compression system that averages the color values of pixels near color breaks, any precise effect applied to a color might appear with ragged edges. In these cases, a TIF or BMP might be a better graphic format choice.

Portable Network Graphics (PNG, and pronounced ping) files were initially developed for the Internet. For Premiere Elements's needs, the chief advantage of this format is that it can be created with transparent areas that remain transparent when the image is placed in your video timeline.

The Graphic Interchange Format (GIF) was developed by CompuServe and is correctly pronounced jiff. This format was initially developed for the Internet and has advantages related to its color management properties that are relevant to web design. For Premiere Elements's needs, the chief advantage of this format is that it can be created with transparent areas that remain transparent when the image is placed in your video timeline.

The Portable Document File (PDF) format was created by Adobe, which has long promoted the format's use as a lightweight, universal way to transfer text and graphics files between programs.

Encapsulated Post Script (EPS) files are unique in that they are usually a vector rather than raster format. The difference between these two formats is that raster images are composed of blocks of pixels while vector images are defined by a series of outline points that designate fields of color (a square, for instance, is defined only by its four corners). The main advantage to using a vector graphic is that, unlike raster images, you do not need to worry about resolution. Because a vector image is defined by outline points rather than being painted with blocks of color, it can be scaled to any size without becoming pixilated. This advantage is somewhat nullified by the fact that after a vector EPS is added to the Timeline of your video, it becomes a piece of raster art by nature of the medium. Therefore, you still need to concern yourself with issues such as resolution and the dangers of over-scaling your image.

NOTE

Although EPS files are presumed to be vector art, programs such as Photoshop can produce raster EPS files. Only EPS files created in a vector art program, such as Adobe Illustrator, will produce true vector EPS files.

KEY TERM

Resolution The pixel density of an image. Print images require a much higher resolution (200300 pixels per inch) than onscreen images (about 72 pixels per inch), but too little resolution in any medium reveals the pixels that make up the image, making the picture look jagged.

1.	Size Your Image Efficiently The primary issue for you to consider when working with any still image you plan to use in your video is the image's resolution. If you use a still image straight from your digital camera (today's 3.5 megapixel digital cameras produce images at 2048x1536 pixels, nearly 10 times the size of a video frame), the still file is too large to be handled efficiently by Premiere Elements. On the other hand, if the still image doesn't contain enough pixels, you won't be able to zoom in on or pan the image in the video project without the image becoming pixelated. See 70 Pan and Zoom Still Images a la Ken Burns. Unlike most digital imagery, video is composed of non-square pixels. NTSC video (a frame made up of 720x480 pixels) uses pixels that are about 90% as wide as they are tall to produce standard 4:3 video and 120% wider than they are tall to produce a 16:9 widescreen video. The PAL system (a frame of 786x576 pixels) uses pixels that are 106% wider than they are tall for standard video and 142% wider than they are tall for widescreen. Fortunately, you won't need to reshape the pixels in your stills before placing them in your video. Premiere Elements converts standard, square-pixel images to their non-square pixel equivalents automatically. NOTES Because a video frame is made up of non-square pixels and most digital images are made up of square pixels, the pixel dimensions for a full-screen image are different for stills and photos than they are for video. Here are approximate dimensions for full-screen graphics in each video system: NTSC's 720x480 non-square video pixel TV screen is approximately equal in size to a graphic that measures 720x535 square pixels. PAL's 786x576 non-square video pixel TV screen is approximately equal in size to a graphic that measures 835x576 square pixels. Don't worry that your graphics are composed of square pixels and video is composed of non-square pixels. Premiere Elements renders your graphics to a full screen of video as long as you use the dimensions given here. Should you work in widescreen video, the following dimensions will work for your graphics (oddly, for widescreen video, only the non-square pixel shapes changethey're much widerthe actual number of video pixels are the same as for standard video): NTSC's 720x480 non-square video pixel widescreen is approximately equal in size to a graphic that measures 865x480 square pixels. PAL's 786x576 non-square video pixel widescreen is approximately equal in size to a graphic that measures 1220x576 square pixels. The goal is to find a balance between too much and too little resolution for your stills. Assume that you're going to load your photo into a standard NTSC 720x480 video and that you plan to zoom in to a spot about a fourth of the area of the image. (In other words, you're going to scale the image to four times the area of the screen.) What does the resolution of the original still image file have to be? A 720x480 NTSC screen has an area of about 345,000 pixels. Four times that size is about 1,380,000 square pixels, or approximately 1440x960about twice the width and twice the height. Too much math? Don't worry about it. A rough estimation is usually more than adequate. If you plan to scale your image to 2 or 3 times the screen size, use an image about 1 and a half times each dimension; if you plan to scale your image to 4 times the screen size, double each dimension, and so on. A little extra resolution doesn't hurt, but a lot extra does. And it's unlikely that you'll ever need an image with more than 2,500 pixels in either dimension. TIP If you have a 14 megapixel still camera, you can generally import an image file from the camera straight into Premiere Elements. Premiere Elements resizes the image as needed, and you should have enough extra resolution to zoom and pan if you chose to do that. If you need to resize a super-high-resolution image file before importing it into Premiere Elements, you must size it using an outside graphics program such as Photoshop Elements or Paint Shop Pro. After the image is sized to the necessary video dimensions, you'll be able to easily work with it in Premiere Elements.
2.	Add Your Still to the Media Panel Click the Add Media button in the shortcuts bar and select From Files and Folders. Browse and select the (resized) photo or photos you want to add to your project. (See 14 Add Media with the Adobe Media Downloader.) You might find it helpful to create a new folder in your Media panel for your still images to better organize your media (see 16 Create and Use Media Folders).
3.	Place Your Still on the Timeline When you add the still to the project Timeline, it becomes a clip at the default duration, initially 5 seconds (see 24 Set Still Image Duration for information on how to change this default setting) and, by default, is sized to the video frame (see 23 Scale and Position a Still for information on how to change this default setting).

NOTE

Although Premiere Elements accepts most major graphics formats, including TIFs, it does not accept 16-bit TIFs or images in any format saved in CMYK color mode.