-BY SAMPATH SAGAR( ) ABHISHEK ANAND( )

MOTION CAPTURING

 The use of motion capture to animate characters on computers is relatively recent, it started in the 1970s, and now just beginning to spread.  Motion Capture is an expensive process that captures the motion of human actors and translates it into digital form so that artists can create more realistic animations of humans on the move.

 Motion capture for animation is the superposition of human movement on their virtual identities.  This capture can be direct, such as the animation arm of a virtual function of movement of an arm, or indirect, such as that of a human hand with a more thorough as the effect of light or color.

 Animation  Video Games  Robot Control  Biomedical research into physiological movement and gait analysis.  Motion picture industry to provide lifelike movement to computer generated characters.  Live and recorded artistic performances.  Interactive virtual reality training simulations.

 The Mechanical motion capture  The Optical motion capture  The Magnetic motion capture

 ABSTRACT 1. Use of an exoskeleton. 2. Each joint is then connected to an angular encoder. 3. The value of movement of each encoder (rotation etc...) is recorded by a computer. 4. Knowing the relative position encoders (and therefore joints) can rebuild these movements on the screen using software. 5. An offset is applied to each encoder.

 This technique offers high precision and it has the advantage of not being influenced by external factors (such as quality or the number of cameras for optical mocap).  Because of the relatively quick analog to digital post-processing, this system can be used in real time performances.

 Exoskeleton generally use wired connections to connect the encoders to the computer.  The freedom of movement is rather limited.  The accuracy of reproduction of the movement depends on the position encoders and modeling of the skeleton.  Pricing for electromechanical systems is approximately $5,000 to $10,000.  Finally, each object to animate to need an exoskeleton, thereby bringing about a scene involving several people will be very difficult to implement.

 Optical motion capture employs between 4 and 32 cameras to film the actor performing the necessary movements at speeds from 30 to 1000 frames per second.  The actor wears small reflective markers on their clothes.  When all the different camera inputs are combined and processed, 3 dimensional data representing the points is produced.

 The operating principle is similar to radar.  The synthesis of coordinates (x, y) of the same object from different angles, allows to deduce the coordinates (x, y, z).  Consideration of complex problems such as optical parallax, distortion lens used, etc.

 Optical systems have problems when markers become occluded from the camera.  In addition to this a tremendous amount of processing and time is required to clean the data enough to make it usable for motion capture applications.  Can cost between $100,000 and $250,000.

 Magnetic motion capture is done through a field of electro-Magenta is introduced in which sensors are coils of sensors electriques.  Electromagnetic systems produce low- frequency electromagnetic fields which are picked up by sensors on the motion capture actor.

 The sensors can then report their movement and orientation based on the field to a central processing unit.  This allows for near real-time processing and performances.  Magnetic data is usually fairly clean as compared to other systems.

 Magnetic systems are adversely affected by even small amounts of electromagnetic noise as well as the presence of ferrous metals in the vicinity.  Electromagnetic system prices vary from $5,000 to $150,000.

 Although the motion capture requires some technical means, we can quite get what to do it yourself at home in a reasonable cost that can make your own short film.  Motion capture is a major step forward in the field of cinema.  Reprocessing the image in a more simple, in fact, it is easier to modify an image captured a classic scene, all although this is too expensive.

 But it is also a major asset in medicine, for example, it can be used to measure the benefit of a transaction via a recording of the movement of the patient before and after the operation (such as in the case of the application a prosthesis, or simply at a medical classic (in the future perhaps).