FULLDOME STANDARDS SUMMIT IPS 2004 Standardize Show Creations.

FULLDOME STANDARDS SUMMITIPS 2004

Standardize Show Creations

SUMMARY

1 Video: Projection System Specifications

2 Images: Rendering, Resolution, Splitting

3 Sound: Reproduction systems, exchange format

1 Video: Projection System Specifications

• Video standards

• Projection System Resolution

• Projection System Frequency

Video Standards

• PAL/SECAM 720*57625fps

• NTSC 720*480 30fps

• HDTV ->16/9 Format not adapted to 4/3 models used

Projection System Resolution

• Graphical Channel:

– Projector

• DLP 1280 * 1024 (SXGA)

• CRT 3200 * 2560

– Computer

• Graphical Card 2048 * 1536

– MicroProcessor

• Video 1600 * 1200 (UXGA)

• Real Time 1600 * 1200 (UXGA)

• Computer Frequency (cinema 24fps)– 25fps (Historically ->PAL)

– 30fps (Historically ->NTSC)

• Projection Frequency– 75Hz

• adapted to 25fps (cycle 3)

• 30fps acceptable to broadcast (cycle 3-2)

– 60Hz• adapted to 30fps (cycle 2)

• 25fps difficult to broadcast (cycle 3-2-3-2-2)

Projection System Frequency

Resolution, Frequency and Rendering Time

• Rendering Time according to the resolution

Average on a P4 2.4GHz mono-processor

• Rendering at 25fps instead of 30fps allows a 20% reduction of rendering time and image storage

2 Images: Rendering, Resolution, Splitting

• Fish-Eye Image Generation

• Fish-Eye Resolution Approach

• Fish-Eye Image Splitting

Fish-Eye Image Generation

• Direct Fish-Eye Rendering

• Hemi-cubic Rendering

• Camera Rendering

Fish-Eye Resolution Approach• Effective Pixels of the Projection System

– Number of Channels * Video Resolution - 20% of soft-edge

• Effective Pixels of the Fish-Eye image (square image)– Area in pixels of the circle in « Image Height » diameter

• 10% Increase

Fish-Eye Image Splitting

• To obtain a Fish-Eye image with one file per channel

• Special Software creation

• Necessity to standardize the different projection configurations– Number of projectors

– Hemispherical Screen Covering (165°, 170°, 180°)

– Camera Parameters

3 Sound: Reproduction System, Exchange Format

• Sound Reproduction Systems

• File Format and Exchange

Reproduction Systems

• 5 + 1

• 7 + 1

• Others…

-> Loudspeaker standardization for a sound with the same quality anywhere in the dome

Files Format and Dispatching

• PCM 48KHz (mono file: around 125Mb for 25 minutes)

• Supplying of (= around 3.75 Gb):

– 7+1 with voice OV: 8 mono files

– 5+1 with voice OV: 6 mono files

– 7+1 without voice: 8 mono files

– 5+1 without voice: 6 mono files

– OV Voice: 1 stereo file

Conclusion

To Define a Standard:• To take into account the world market

specifications• The market must not adapt itself to the standard,

but the standard must adapt itself to the market• It must be always possible to adapt a standardized

show to a non standard planetarium