Introduction - Computer Animation: Algorithms and Techniques - page 14

Framing
Framing refers to allowing enough room in the image for the action being captured. In a relatively static
view, allow enough room so the subject does not fill the frame (unless there is a reason to do so). Allow
enough room for motion. If your subject is walking, frame the motion so there is room in front of the
subject so the subject does not appear to be walking out of the frame.
Focus the viewer's attention
Draw the viewer's attention to what's important in the image. Use color, lighting, movement, focus,
etc., to direct the attention of the viewer to what you want the viewer to see. For example, the eye will
naturally follow converging lines, the gaze of figures in the image, a progression from dark to light or
dark to bright, and an identifiable path in the image.
1.3.3 Sound
Sound is an integral part of almost all animation, whether it's hand-drawn, computer-based, or stop-
motion [ 23 ] [ 26 ]. Up through the 1920s, the early “silent films” were played in theaters with live mood
music accompaniment. That changed as sound recording technology was developed for film and, later,
for video.
Audio recording techniques had been around for 30 years by the time moving images were first
recorded on film. It took another 30 years to develop techniques for playing a sound track in sync
with recorded action. Since then, various formats have been developed for film sound tracks. Most
formats record the audio on the same medium that records the images. In most of the various formats
for film, for example, audio is recorded along the side of the images or between the sprocket holes in
one to six tracks. Early formats used optical or magnetic analog tracks for sound, but more recent for-
mats digitally print the sound track on the film. By recording the audio on the same stock as the film, the
timing between the imagery and the audio is physically enforced by the structure of the recording tech-
nology. In some formats, a separate medium, such as a CD, is used to hold the audio. This allows more
audio to be recorded, but creates a synchronization issue during playback. In the case of video, audio
tracks are recorded alongside the tracks used to encode the video signal.
In the early film and video formats, audio was recorded as a low bandwidth analog signal resulting
in very low-quality sound. Today's film and video technology acknowledges the importance of sound
and provides multiple, high-quality digital audio tracks. Sound has four roles in a production: voice,
body sounds, special effects, and background music.
In live action, voice is recorded with the action because of timing considerations while most of the
other sounds are added in a post-processing phase. In animation, voices are recorded first and the ani-
mation made to sync with it. In addition, recording visuals of the voice talent during the audio recording
can be used to guide the animators as they create the facial expressions and body language that accom-
panies the speech.
Nonspeech sounds made by the actors, such as rustling of clothes, footsteps, and objects being han-
dled, are called body sounds. The recorded body sounds are usually replaced by synthesized sounds,
called foley , for purposes of artistic control. These synthesized sounds must be synced with the motions
of the actors. The people responsible for creating these sounds are called foley artists .
Special effects, such as door slams and the revving of car engines, must also be synced with the
action, but with lesser precision than voice and foley sounds.