27-04-2011, 10:04 AM
PRESENTED BY:
Sandeep Kumar
[attachment=12893]
What is AR?
ä Augmented Reality (AR) is a variation of VE/VR.
VR technologies completely immerse a user inside a synthetic environment. While immersed, the user cannot see the real world around him.
In contrast, AR allows the user to see the real world, with virtual objects superimposed upon or composited with the real world.
ä AR supplements reality, rather than completely replacing it. It creates the illusion that the virtual and real objects coexisted in the same space.
ä AR can be thought of as the "middle ground“ between VE (completely synthetic) and telepresence (completely real)
ä AR systems have the following three characteristics:
Combines real and virtual
Interactive in real time
Registered in 3-D
ä This definition allows other technologies besides Head Mounted Displays (HMDs) while retaining the essential components of AR.
ä Does not include film or 2-D overlays like "Jurassic Park" featuring photorealistic virtual objects seamlessly blended with a real environment in 3-D, as they are not interactive.
ä 2-D virtual overlays on top of live video can be done at interactive rates, but the overlays are not combined with the real world in 3-D. Hence, they are not AR.
Motivation
ä AR enhances a user’s perception of interaction with the real world.
ä The virtual objects display information that the user cannot directly detect with his own senses.
ä The information conveyed by the virtual objects helps a user perform real-world tasks.
ä AR is a specific example of what is known as Intelligence Amplification (IA): using the computer as a tool to make a task easier for a human to perform.
Applications
ä Main classes of applications:
1. Medical
2. Manufacturing and repair
3. Annotation and visualization
4. Robot path planning
5. Entertainment
6. Military aircraft
There are several miscellaneous applications
Characteristics
ä Discussion on the characteristics of AR systems and design issues encountered when building an AR system.
ä Two ways to accomplish this augmentation: optical or video technologies.
ä Blending the real and virtual poses problems with focus and contrast and some applications require portable AR systems to be truly effective.
Characteristics: Augmentation
ä Besides adding objects to a real environment, AR also has the potential to remove them.
ä Graphic overlays might be used to remove or hide parts of the real environment from a user. e.g., to remove a desk in the real environment, draw a representation of the real walls and floors behind the desk and "paint" that over the real desk, effectively removing it from the user's sight.
ä Has been done in movies. Doing this interactively in an AR system will be much harder, but this removal may not need to be photorealistic to be effective.
ä Blending the real and virtual poses problems with focus and contrast and some applications require portable AR systems to be truly effective.
ä AR might apply to all senses, not just sight.
ä AR could be extended to include sound.
ä The user would wear headphones equipped with microphones on the outside. The headphones would add synthetic, directional 3D sound, while the external microphones would detect incoming sounds from the environment. Thus, one can cancel selected real incoming sounds and add others to the system. This is not easy, but possible.
ä Another example is haptics.
ä Gloves with devices that provide tactile feedback might augment real forces in the environment. For example, a user might run his hand over the surface of a real desk which can augment the feel of the desk, perhaps making it feel rough in certain spots.
Characteristics: Focus & Contrast
ä Focus can be a problem for both optical and video components. Ideally the virtual should match the real.
Depending on video camera’s depth-of-field (DOF) and focus settings, parts of the real world may not be in focus.
In computer graphics, everything is rendered with a pinhole model, so regardless of distance, everything is in focus.
To overcome this, graphics can be rendered to simulate a limited DOF, and the video camera can have autofocus lens.
ä Contrast is a big issue owing to its large dynamic range in real environments.
The eye is a logarithmic detector simultaneously handling contrasts varying by 6 orders! Most display devices do not even come close.
Thus optical devices are usually made dark-tinted to reduce this range. For video, everything must be clipped or compressed into the monitor’s dynamic range.
Sandeep Kumar
[attachment=12893]
What is AR?
ä Augmented Reality (AR) is a variation of VE/VR.
VR technologies completely immerse a user inside a synthetic environment. While immersed, the user cannot see the real world around him.
In contrast, AR allows the user to see the real world, with virtual objects superimposed upon or composited with the real world.
ä AR supplements reality, rather than completely replacing it. It creates the illusion that the virtual and real objects coexisted in the same space.
ä AR can be thought of as the "middle ground“ between VE (completely synthetic) and telepresence (completely real)
ä AR systems have the following three characteristics:
Combines real and virtual
Interactive in real time
Registered in 3-D
ä This definition allows other technologies besides Head Mounted Displays (HMDs) while retaining the essential components of AR.
ä Does not include film or 2-D overlays like "Jurassic Park" featuring photorealistic virtual objects seamlessly blended with a real environment in 3-D, as they are not interactive.
ä 2-D virtual overlays on top of live video can be done at interactive rates, but the overlays are not combined with the real world in 3-D. Hence, they are not AR.
Motivation
ä AR enhances a user’s perception of interaction with the real world.
ä The virtual objects display information that the user cannot directly detect with his own senses.
ä The information conveyed by the virtual objects helps a user perform real-world tasks.
ä AR is a specific example of what is known as Intelligence Amplification (IA): using the computer as a tool to make a task easier for a human to perform.
Applications
ä Main classes of applications:
1. Medical
2. Manufacturing and repair
3. Annotation and visualization
4. Robot path planning
5. Entertainment
6. Military aircraft
There are several miscellaneous applications
Characteristics
ä Discussion on the characteristics of AR systems and design issues encountered when building an AR system.
ä Two ways to accomplish this augmentation: optical or video technologies.
ä Blending the real and virtual poses problems with focus and contrast and some applications require portable AR systems to be truly effective.
Characteristics: Augmentation
ä Besides adding objects to a real environment, AR also has the potential to remove them.
ä Graphic overlays might be used to remove or hide parts of the real environment from a user. e.g., to remove a desk in the real environment, draw a representation of the real walls and floors behind the desk and "paint" that over the real desk, effectively removing it from the user's sight.
ä Has been done in movies. Doing this interactively in an AR system will be much harder, but this removal may not need to be photorealistic to be effective.
ä Blending the real and virtual poses problems with focus and contrast and some applications require portable AR systems to be truly effective.
ä AR might apply to all senses, not just sight.
ä AR could be extended to include sound.
ä The user would wear headphones equipped with microphones on the outside. The headphones would add synthetic, directional 3D sound, while the external microphones would detect incoming sounds from the environment. Thus, one can cancel selected real incoming sounds and add others to the system. This is not easy, but possible.
ä Another example is haptics.
ä Gloves with devices that provide tactile feedback might augment real forces in the environment. For example, a user might run his hand over the surface of a real desk which can augment the feel of the desk, perhaps making it feel rough in certain spots.
Characteristics: Focus & Contrast
ä Focus can be a problem for both optical and video components. Ideally the virtual should match the real.
Depending on video camera’s depth-of-field (DOF) and focus settings, parts of the real world may not be in focus.
In computer graphics, everything is rendered with a pinhole model, so regardless of distance, everything is in focus.
To overcome this, graphics can be rendered to simulate a limited DOF, and the video camera can have autofocus lens.
ä Contrast is a big issue owing to its large dynamic range in real environments.
The eye is a logarithmic detector simultaneously handling contrasts varying by 6 orders! Most display devices do not even come close.
Thus optical devices are usually made dark-tinted to reduce this range. For video, everything must be clipped or compressed into the monitor’s dynamic range.
