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ANIMATE takes a series of animation “frames” and strings them together as with celluloid film to make a “movie”. This may be an animated real-life photograph or a flashing poster-colour sign.
The basis for these animations is GIF - the GRAPHICS INTERCHANGE FORMAT. This alone will support animation. It is true that there is the official MPEG system of digital TV, but few browsers support it.
GIF gives an automatic three-fold compression by limiting the choice of colours to 256, that is to say, one byte per colour rather than the three bytes in 16-megacolour BMP files. The subtlety of a photo can be lost, so always work with BMP files until the photo has been cut down to the smallest size. Converting to GIF at the last minute ensures that the palette (see right) contains colours that are actually used.
To obtain the three-fold compression, the palette - also called the colour look-up-table - has to be sent with the file. This costs 768 bytes for 256 colours.
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