Unit 13. Basic Level. Animations Frame by Frame
The Animation in Flash
An animation is nothing more than a sequence of frames reproduced at a so high speed that the human eye isn't able to perceive the change from one image to another one.
Although the limit in which the human eye detects these changes on the monitor of a computer goes up approximately to 18 frames per second, Flash places by default its lines of 12 times to fps, due to that some monitors don’t support well enough this frequency.
Flash incorporates techniques that apparently don’t use successive sequences of frames, like the motion tweening. In these cases, we don’t see frames "physically", or in other words, if the animation takes 20 frames in the timeline, the fact that not all of them are keyframes simply indicates an improvement in the storage capacity of Flash, because it doesn’t need to know how are the intermediate steps of the animation. If all frames were keyframes, the size of the file would increase considerably.
This last one happens, for example with the animated GIFs, although being widespread used in the Web world. They are not only made up of Bitmaps (we’ve already commented about the larger size of these graphics), but each frame is a complete bitmap, which increases significantly its space of storage in memory and disk.
Creating Frame by Frame animation
Although Flash incorporates superior techniques than these, it also allows "to simulate" the way a GIF creates an animation, since sometimes the animation is very sudden or the change isn’t "automatically” attainable with Flash or simply our objective is to export the graphics created as this type of bitmap.
In order to create a frame by frame animation is enough to introduce the initial appearance of the object in the first frame, make all those frames that are going to take part in it to be keyframes, and modify them, progressively, one by one, since a very great difference of one frame to the following would make an sudden hit to whom visualizes it.
Once the animation is finished we’ll have something like what we show in our timeline:
We'll see the difference in sizes of the different animation techniques for the same movie:
We have the following animation. The appearance will practically stay equal in all these cases, but there is the possibility that by doing it frame to frame, small errors of positioning in the trajectory are committed that Flash wouldn’t commit:
And we have these three forms to create it with its corresponding sizes:
1) Motion Tweening: With the next timeline:
Size: 961 Bytes
2) Frame by Frame exported as Flash (SWF) movie: As we see the timeline has all frames as keyframes:
Size: 1 KByte
3) Frame by Frame exported Animated GIF: The timeline is the same as in the previous case:
Size: 2 KByte
Although the differences would be observed better in more complex movies, in this example we can see how the size is smaller using the technique of Flash 8 of Motion Tweening, it is greater in the frame by frame animation and doubles for the case of an animated GIF.
We've said that sometimes it 's inevitable to make a frame by frame animation. Here is an example of this type.
Legal warning: Authorised on-line use only. It is not allowed the use of these courses in companies or private teaching centres.