Read the following passage
and
mark
the letter
A, B, C or D on your
answer
sheet to indicate
the correct
answer
to each of the following questions
BÀI SỐ 1
Animation traditionally is done by hand-drawing or painting successive frames of an
object, each slightly different than the preceding frame. In computer animation, although
the computer may be the one to draw the different frames, in most cases the artist will
draw the beginning and ending frames and the computer will produce the drawings
between the first and the last drawing. This is generally referred to as computer-assisted
animation, because the computer is more of a helper than an originator.
In full computer animation, complex mathematical formulas are used to produce the
final sequence of pictures. These formulas operate on extensive databases of numbers
that define the objects in the pictures as they exist in mathematical space. The database
consists of endpoints, and color and intensity information. Highly trained professionals
are needed to produce such effects because animation that obtains high degrees of realism
involves computer techniques for three-dimensional transformation, shading, and
curvatures.
High-tech computer animation for film involves very expensive computer systems
along with special color terminals or frame buffers. The frame buffer is nothing more
than a giant image memory for viewing a single frame. It temporarily holds the image for
display on the screen.
A camera can be used to film directly from the computer's display screen, but for the
highest quality images possible, expensive film recorders are used. The computer
computes the positions and colors for the figures in the picture, and sends this
information to the recorder, which captures it on film. Sometimes, however, the images
are stored on a large magnetic disk before being sent to the recorder. Once this process is
completed, it is repeated for the next frame. When the entire sequence has been recorded
on the film, the film must be developed before the animation can be viewed. If the entire
sequence does not seem right, the motions must be corrected, recomputed, redisplayed,
and rerecorded. This approach can be very expensive and time consuming. Often,
computer-animation companies first do motion tests with simple computer-generated line
drawings before selling their computers to the task of calculating the high-resolution,
realistic-looking images.