초록 ▼

A system for compressing and transmitting a digital image signal over a limited bandwidth communication channel, transform codes the image values and quantizes the transform coefficients according to a two-dimensional model of the sensitivity of the human visual system. The model of the human visual

A system for compressing and transmitting a digital image signal over a limited bandwidth communication channel, transform codes the image values and quantizes the transform coefficients according to a two-dimensional model of the sensitivity of the human visual system. The model of the human visual system is characterized by being less sensitive to diagonally oriented spatial frequencies than to horizontally or vertically oriented spatial frequencies, thereby achieving increased compression of the image.

대표청구항 ▼

A transmitter for compressing and transmitting a digital image over a limited bandwidth communication channel comprising: (a) means for performing a two-dimensional spatial frequency transformation on the digital image to produce transform coefficients; and (b) means for quantizing the transform coe

A transmitter for compressing and transmitting a digital image over a limited bandwidth communication channel comprising: (a) means for performing a two-dimensional spatial frequency transformation on the digital image to produce transform coefficients; and (b) means for quantizing the transform coefficients in accordance with a two-dimensional model of the sensitivity of the human visual system to spatial frequencies, said model of the human visual system including the feature that the human visual system is less sensitive to diagonally oriented spatial frequencies than to horizontally or vertically oriented spatial frequencies.