Pencil To Animator

Motion capture is the process of recording the
movement of objects or people. It is used in
military , entertainment, sports , and medical
applications, and for validation of computer
vision [2] and robotics. In filmmaking and video
game development, it refers to recording actions
of human actors, and using that information to
animate digital character models in 2D or 3D
computer animation. When it includes face and
fingers or captures subtle expressions, it is
often referred to as performance capture . In
many fields, motion capture is sometimes called
motion tracking , but in filmmaking and games,
motion tracking more usually refers to match
moving .
In motion capture sessions, movements of one
or more actors are sampled many times per
second. Whereas early techniques used images
from multiple cameras to calculate 3D
positions, often the purpose of motion capture
is to record only the movements of the actor,
not his or her visual appearance. This
animation data is mapped to a 3D model so
that the model performs the same actions as
the actor. This process may be contrasted to
the older technique of rotoscope , such as the
Ralph Bakshi 1978 The Lord of the Rings and
1981 American Pop animated films where the
motion of an actor was filmed, then the film
used as a guide for the frame-by-frame motion
of a hand-drawn animated character.
Camera movements can also be motion
captured so that a virtual camera in the scene
will pan, tilt, or dolly around the stage driven by
a camera operator while the actor is performing,
and the motion capture system can capture the
camera and props as well as the actor's
performance. This allows the computer-
generated characters, images and sets to have
the same perspective as the video images from
the camera. A computer processes the data and
displays the movements of the actor, providing
the desired camera positions in terms of objects
in the set. Retroactively obtaining camera
movement data from the captured footage is
known as match moving or camera tracking .
Advantages
Motion capture offers several advantages over
traditional computer animation of a 3D model:
More rapid, even real time results can be
obtained. In entertainment applications this can
reduce the costs of keyframe-based animation.
The Hand Over technique is an example of this.
The amount of work does not vary with the
complexity or length of the performance to the
same degree as when using traditional
techniques. This allows many tests to be done
with different styles or deliveries, giving a
different personality only limited by the talent of
the actor.
Complex movement and realistic physical
interactions such as secondary motions, weight
and exchange of forces can be easily recreated
in a physically accurate manner.
The amount of animation data that can be
produced within a given time is extremely large
when compared to traditional animation
techniques. This contributes to both cost
effectiveness and meeting production deadlines.
Potential for free software and third party
solutions reducing its costs.
Disadvantages
Specific hardware and special software
programs are required to obtain and process
the data.
The cost of the software, equipment and
personnel required can be prohibitive for small
productions.
The capture system may have specific
requirements for the space it is operated in,
depending on camera field of view or magnetic
distortion.
When problems occur, it is easier to reshoot
the scene rather than trying to manipulate the
data. Only a few systems allow real time
viewing of the data to decide if the take needs
to be redone.
The initial results are limited to what can be
performed within the capture volume without
extra editing of the data.
Movement that does not follow the laws of
physics cannot be captured.
Traditional animation techniques, such as
added emphasis on anticipation and follow
through, secondary motion or manipulating the
shape of the character, as with squash and
stretch animation techniques, must be added
later.
If the computer model has different
proportions from the capture subject, artifacts
may occur. For example, if a cartoon character
has large, over-sized hands, these may
intersect the character's body if the human
performer is not careful with their physical
motion.