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ADOBE PHOTOSHOP CS2
User Guide
Optimizing animations
After you complete your animation, you should optimize it for efficient download to a web browser. You optimize an
animation in two ways:
•
Optimize the frames to include only areas that change from frame to frame. This greatly reduces the file size of the
animated GIF. See “To optimize an image for the web” on page 628 and “Optimization options for GIF and PNG
8 formats” on page 635.
•
If you are saving your animation as a GIF image, optimize it as you would any GIF image. A special dithering
technique is applied to animations to ensure that dither patterns are consistent across all frames and to prevent
flickering during playback. Because of these additional optimization functions, more time may be required to
optimize an animated GIF than to optimize a standard GIF.
When optimizing the colors in an animation, use the Adaptive, Perceptual, or Selective palette. This ensures that the
colors are consistent across frames. (See “Optimization options for GIF and PNG-8 formats” on page 635.)
To optimize animation frames
1
Choose Optimize Animation from the Animation palette menu.
2
Set the following options:
Bounding Box
Crops each frame to the area that has changed from the preceding frame. Animation files created
using this option are smaller but are incompatible with GIF editors that do not support the option. (This option is
selected by default and is recommended.)
Redundant Pixel Removal
Makes transparent all pixels in a frame that are unchanged from the preceding frame.
This option is selected by default and is recommended. The Transparency option in the Optimize palette must be
selected for redundant pixel removal to work. (See “Optimization options for GIF and PNG-8 formats” on page 635.)
Important:
Set the frame disposal method to Automatic when using the Redundant Pixel Removal option. (See “Setting
the frame disposal method” on page 620.)
3
Click OK.
Saving and exporting animations
You can save animations in several formats.
GIF
A standard format for saving animated images for viewing on the web. In Photoshop you use the Save For Web
dialog box. In ImageReady you use the Optimize palette to set GIF options. See “Optimization options for GIF and
PNG-8 formats” on page 635.
QuickTime movie (ImageReady)
(See “To save files in QuickTime Movie format (ImageReady)” on page 671.)
SWF (Macromedia® Flash™) file (ImageReady)
(See “Saving files in SWF format (ImageReady)” on page 671.)
In ImageReady, you can also save each frame in an animation as a separate file. See “Exporting animation frames as
files” on page 676.
