מערכות ראיה ושמיעה Visual and Auditory Systems. Spectrum

מערכות ראיה ושמיעהVisual and Auditory SystemsVisual and Auditory Systems

Spectrum

Photometry• Measuring light …

Colorimetry• Modeling of color sensation

• Color addition• Color subtraction• Image processing

(noise removal, edge detection, compression, inpainintg etc.)

Bayer filter

Colorimetry• CIE

standard observer

• RGBcolor addition

• HSV• CMYK

color subtraction

• YIQ, YUVtelevision broadcasting

• YCbCrdigital television transmission, JPEG

CIE gamut

HSV gamut

• Dichromatism:

Colorimetry

The Human Visual System (HVS)

The Human Visual System (HVS)

Vision Research• Physiology• Psychophysics

Automatic Gain Control

Hermann’sGrid

Vision Research

Vision Research• HVS is sensitive to:

• Local features.• Spatial frequency (gratings).

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Contrast Sensitivity Function

Signal Representation• How does the HVS represent

images?• Fourier series.• Gabor functions.• Wavelets

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The Ear

Subjective Hearing

• Properties of the human auditory system are utilized in audio compression algorithms such as MP3.