…may not smell so sweet. Sorry, Mr. Shakespeare! As I begin to put together a FAQ on digital storytelling and as a follow-up to my “Pixel Perfect” post, I thought it might be a good time to talk about the alphabet soup of picture/graphic extensions.
BMP, "bitmapped", is the uncompressed standard for Windows computers. I assume PC video editing programs prefer this format for importing stills just as Mac video editing programs do better with PICT.
EPS is "encapsulated post script" format and is the biggest and the best. Because the graphic is described by an algorithm for its shapes, resizing doesn’t ruin the quality. If you have one these and you “tug” on a corner to stretch or enlarge it, you’ll see that the quality stays constant. Too big for Internet use,presentation software shouldn’t have a problem with it and some video editing programs (especially the high end apps) should be able to import it.
GIF is the "graphical interchange format." (The old linguist in me prefers the hard “g” pronunciation over “jif.”) This is a very effective compression method that only uses 256 colors. That economy of space and load time makes it an Internet standard for display and animation. And that same parsimony makes it next to useless for a video, especially if movement or resizing is a possibility.
JPEG/JPG is the other Internet standard from the Joint Photographic Experts Group. This is probably the best compromise between quality and size. Your digital still camera most likely saves in this format. You can use a good quality JPEG in a video, but its actual, physical size will make a difference (that’s why you should set your still camera to the highest quality). This is where Bernajean’s 720×534 pixel commandment or my 6×9 inch rule of thumb should be followed when you are filling the screen or zooming or panning. (FYI, a zoom moves in or out on a point in a picture. A pan, on the other hand, just moves from one place to another. If you look at my daughter and son-in-law’s preschool picture/movie two posts ago, you’ll see a combination of the two. It starts zoomed in on the class and year, pans up to my little girl while zooming out just a bit, then pans to her future husband, and pans down to another student before finally zooming out to the whole class.)
PICT/PCT is the uncompressed "picture" standard for the Macintosh platform. Use this format when inserting scanned stills into video. However, a wallet size picture still won’t show well if it isn’t scanned at a high resolution to withstand resizing and movement.
PNG, "portable network graphic – ping" is apparently higher quality than GIF and takes less space than JPEG. (A close relative, MING – multiple image network graphic, is used like animated GIF’s for web animation.) If you have to use one in a video (may not be recognized by all editing programs), follow the advice for JPEG’s above.
TIFF, "tagged image file format." They are also very high quality, uncompressed images. Way too big for the Internet, but another good choice for video if your editing program can accept it. This is my personal preference for saving scans.
O picture quality, wherefore art thou?