Scripts and expressions for working with text – Adobe After Effects User Manual
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Best practices for creating text and vector graphics for video
Text that looks good on your computer screen as you are creating it can sometimes look bad when viewed in a final output movie. These
differences can arise from the device used to view the movie or from the compression scheme used to encode the movie. The same is true for
other vector graphics, such as shapes in shape layers. In fact, the same problems can occur in raster images, but the small and sharp details of
vector graphics cause the problems most often.
Keep in mind the following as you create and animate text and vector graphics for video:
You should always preview your movie on the same kind of device that your audience will use to view it, such as an NTSC video monitor.
(See Preview on an external video monitor.)
Avoid sharp color transitions, especially from one highly saturated color to its complementary color. Sharp color transitions are difficult for
many compression schemes—such as the compression schemes in MPEG and JPEG standards—to encode. These compression schemes
can cause visual noise near sharp transitions. For analog television, the same sharp transitions can cause spikes outside the allowed range
for the signal, also causing noise.
When text will be over moving images, make sure that the text has a contrasting border (such as a glow or a stroke) so that the text is still
readable when something the same color as the fill passes behind the text.
Avoid thin horizontal elements, which can vanish from the frame if they happen to be on an even scan line during an odd field, or vice versa.
The height of the horizontal bar in a capital H, for example, should be three pixels or greater. You can thicken horizontal elements by
increasing font size, using a bold (or faux bold) style, or applying a stroke. (See
.)
When animating text to move vertically—for scrolling credits, for example—move the text vertically at a rate in pixels per second that is an
even multiple of the field rate for the interlaced video format. Such a rate of movement prevents a kind of twitter that can come from the text
movement being out of phase with the scan lines. For NTSC, good values include 0, 119.88, and 239.76 pixels per second; for PAL, good
values include 0, 100, and 200 pixels per second.
Apply the Autoscroll - Vertical animation preset in the Behaviors category to quickly create a vertical text crawl (for example, a credit roll).
To avoid the risk of twitter that comes with vertical motion, thin graphical elements, and fields, consider presenting credits as a sequence of
blocks of text separated by transitions, such as opacity fades.
Fortunately, many problems with text in video and compressed movie formats can be solved with one simple technique: Apply a blur to the text
layer. A slight blur can soften color transitions and cause thin horizontal elements to expand. The Reduce Interlace Flicker effect works best for the
purpose of reducing twitter; it applies a vertical directional blur but doesn't blur horizontally, so it degrades the image less than other blurs.
Philip Hodgetts provides tips on the
for getting the best results when creating text or vector graphics for video.
Scripts and expressions for working with text
Christopher Green provides a script (crg_Text_from_File.jsx) on
that creates one or multiple text layers based on the contents of a text
file. You can either create one text layer from all of the text, or you can create one layer for each line in the text file. The script also provides
options for leading and other spacing.
Todd Kopriva provides an example script on the
that demonstrates the text formatting features available through the scripting
interface.
Salahuddin Taha provides a script on the
enables entry of Arabic text (which flows from right to left).
Michael Cardeiro provides a script on the
makes multiple versions of your compositions using information from a
spreadsheet or database. The script goes through your spreadsheet line by line, making a new version of your composition with text layers in the
composition receiving text from the spreadsheet automatically.
The
many scripts for working with text. Paul Tuersley provides a script on the
that allows you to search for and edit text layers throughout your After Effects project, create your own text style presets, and apply them to
multiple layers.
Paul Tuersley provides a script on the
importing Substation Alpha (SSA) karaoke files and automatically creating animated
text layers from them.
Jeff Almasol provides a script on his
for editing the source text of text layers.
Jeff Almasol provides a script on his
that converts various plain text punctuation into their “smart” typographical representations
(for example, (c) is converted to the copyright symbol, ©).
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