Overview

How to make an animation

Q)

What technique should I use to animate a 320x224 graphic at 8fps? Reading from a CD-ROM cannot keep up with the process, and there are too many graphics to be read into memory, resulting in insufficient memory.

A)

In order to display still image data continuously, it must be stored as various video playback formats, but this is done with a commercially available authoring tool.

If you try to display only full-screen image data while reading uncompressed data directly from a CD-ROM, for example, if you set the number of colors to 32k, simply think about it.

320 x 224 x 16 (bit) x 8 (fps) = 9,830,400 bit / sec
(1,228,800 byte / sec)

It is impossible as long as you are using a CD-ROM. So, how many software achieves this is to compress the image, store it, decode it during playback, and expand it to the screen.

The video library packages we supply include Cinepak True Motion and MPEG.
In addition, some software that has already been released has a video package created and used by a unique method.

About Cinepak / TrueMotion playback rate.

Q)

Is it possible to make a 30 frame / sec movie with 320 x 240 instead of 320 x 224 with Cinepak / TRUE MOTION?

A)

In either Cinepak / TrueMotion, it seems impossible to play 30 frames per second at 320x224 or 320x240. Basically, only 300KB / s of data including sound and pictures can be transferred (this is a spec problem of double-speed CDROM), so unless it is a video with very high compression efficiency (almost a single color), it will be at this resolution. Playback is impossible.
As for sound, Cinepak can play even irregular frequency data because the sound data is uncompressed.
By the way, in the case of Cinepak, the amount of sound data required per second is

For 44.1kHz, 16bit, stereo
44100x2x2 = 176kb

It will be necessary.
In the case of TrueMotion, 4-bit compression called DK4bit is also possible, so if you use that to express the same specifications,

44100x2x0.5 = 44.1kb

It will be. By the way, our "Clockwork Knight" is 288x144 and 30fps.