Still Images to Video

Still Images to Video

There is a difference with stills used for computers (desktop video) and those used for TV's (on VHS tape or DVD), due to a problem with interlaced viewing of still images.

Most televisions are interlaced, and this causes a flickering problem when showing still images. Computer monitors are now all non-interlaced (progressive scanning) and therefore have no issues with displaying stills. They DO have a problem with stills that were exported from video (see "Video to Stills").

The Conversion Technique

In Premiere, set your duration on the timeline to 1 frame – goto Edit/Preferences/General and Still Images:

NOTE – the default duration is 150 frames – I use 90 - make sure to switch it back to 90 frames (3 secs) when finished !!!
File/Import . . . select all the stills

Select all of them in the Bin using the Shift Key (or selectively select certain ones with the Control Key)
Drag to timeline
Make Movie
go back to Edit/Preferences/General and Still Images and set the duration back to 90 frames (3 secs)
Done !!!

Interlaced viewing artifacts problem - most Televisions

*** some new TV's are non-interlaced - "Progressive Scanning"

Interlaced screens cause artifacts. The NTSC picture is divided into horizontal lines that are drawn onto the CRT screen in interlaced order--that is, all of the odd-numbered lines are drawn first, then the electron beam retraces to the top of the screen and draws the even-numbered lines.

Without motion, the thin, horizontal lines in any still image will appear to flicker on and off in an obnoxious and eye-catching manner. This behavior is known as "line twitter." Line twitter can appear even on still graphics, where a thin line that appears in the even field but not the odd field will appear to flicker. Motion aggravates the problem. A related but slightly different problem shows up in scrolling titles that appear to shimmer or pulse.

Solution - Blur It !!

The answer is to use directional blurring to antialias the line vertically. This solution usually gets computer graphics folks up in arms. "Blur the graphics?" they generally cry. "But I like my graphics sharp and crisp!" But as you'll see, NTSC graphics must be blurred slightly. NTSC simply doesn't work like an SGA display, either vertically or horizontally, and the shortcomings of the display technology must be considered in the creation of graphics. Interlace artifacts are a problem for NTSC in general. If the graphic is going to be a still or have a pan (but not a zoom where the lines change size), then the blurring can be done once for the entire graphic in Adobe Photoshop.

record a macro on just one of your images to do the following, revert the image to it's initial state, and then and run File/Automate/Batch . . . to apply it to all of your stills. Then import them into Premiere. If you have many stills use the technique mentioned above to make your video.

scale the images to the same size as your video (NTSC for DVD is 720x480)
use the Motion Blur filter with the direction set to vertical (in Photoshop, the Blur defaults to horizontal--aka zero degrees--so you'll have to adjust it to vertical--aka 90 degrees). The amount of blur needed will depend on the exact width of the problem lines - values of 1 or 2 work well.