Patent EA-004242-B1 (EA)
Title: Selected data compression for digital pictorial information
Inventor: VAN DE VEN ANTONY
IPC: H04N7/26
Filed: 2001-03-23
Abstract: 1. A method to transmit or store image data for display on a digital display system comprising: - applying an anti-gamma function to linearize an incoming data value and providing said linearized value as a higher order number; -receiving said linearized higher order number and, if below at least a first threshold value capable of being transmitted or stored on a lower order data system, transmitting or storing said linearized higher order number on said data system for use with a digital display system; and -compressing said higher order numbers above said at least first threshold to also fit said lower order data system for storage or transmission and subsequent uncompression and use with said digital display system. 2. A method to transmit or store image data for display on a digital display system as claimed in claim 1 wherein said at least first threshold value is set to a value less than or equal to a value transmittable or storable on a data system of n-1 channels or bits where n equals the maximum order of the lower order data system. 3. A method to transmit or store image data for display on a digital display system as claimed in claim 1 wherein said higher order values above said first threshold are compressed to values transmittable or storable on a data system ofn-1 channels where n equals the maximum order of the lower order data system. 4. A method to transmit or store image data for display on a digital display system as claimed in claim 1 wherein said threshold value is set to a value corresponding to a value represented by a single active bit in a binary sequence being a value of 2<X> where x is a whole number. 5. A method to transmit or store image data for display on a digital display system as claimed in claim 4 wherein said x equals n-1. 6. A method to transmit or store image data for display on a digital display system as claimed in claim 1 wherein said uncompressed and said compressed values are transmitted or stored on n-1 channels and the remaining channel is used to indicate the state of compression of the value. 7. A method to transmit or store image data for display on a digital display system as claimed in claim 1 wherein said at least first threshold value is set to a value less than or equal to a value transmittable or storable on a data system of n-m channels or bits where n equals the maximum order of the lower order data system and m equals the minimum number of channels or bits to indicate the number of stages of compression. 8. A method to transmit or store image data for display on a digital display system as claimed in claim 7 where said at least first threshold value equals the number of values transmittable or storable on a data system of n-m channels or bits and subsequent threshold values equal said first threshold value multiplied by 2<X> where x is a whole number. 9. An apparatus to transmit or store image data for use with a digital display system comprising: -conversion means to apply an anti-gamma function and linearize a data value to a linearized higher order number; -selection means to select linearized higher order numbers below at least a first threshold value; -compression means to compress linearized higher order numbers above said at least first threshold value; and -output means connectable to a lower order communication or storage system to transmit or store said selected and said compressed values. 10. An apparatus to transmit or store image data for use with a digital display system as claimed in claim 9 wherein said conversion, selection and compression is performed by a programmable memory apparatus. 11. An apparatus to transmit or store image data for use with a digital display system as claimed in claim 10 wherein said programmable memory apparatus comprises an Eprom. 12. An apparatus to transmit or store image data for use with a digital display system as claimed in claim 9 wherein alternatively, said conversion. selection and compression may be performed, at least in part, by a logic circuit. 13. An apparatus to transmit or store image data for use with a digital display system as claimed in claim 9 wherein said selection selects according to at least a first threshold value less than or equal to the maximum value transmittable or storable onn-1 channels where n equals the order of said lower order system. 14. An apparatus to transmit or store image data for use with a digital display system as claimed in claim 13 wherein at least one remaining channels is used to indicate the compression state of the value. 15. An apparatus to transmit or store image data for use with a digital display system as claimed in claim 9 wherein said selection selects according to at least a first threshold value less than or equal to the maximum value transmittable or storable on n-m channels where n equals the order of the lower order system and m equals the minimum channels or bits necessary to represent the number of compressed or uncompressed states. 16. An apparatus to transmit or store image data for use with a digital display system as claimed in claim 15 wherein said at least first threshold value is said to permit the maximum number of values to be transmitted or stored on n-m channels or bits and wherein subsequent threshold values equal said first threshold value multiplied by 2<X> where x is a whole number. 17. An apparatus for the uncompression of transmitted or stored linearized data from a lower order data system into a higher order data system for use with a digital display where said linearized data comprises uncompressed values below at least a first threshold and compressed values above said at least first threshold and an indicating bit or bits to indicate the state of compression of the value comprising: -switching means driven by said indicating bit or bits to select between at least two separate logic operations for incoming linearized data values; -a direct output of said incoming value if said switching means indicates an uncompressed value has been received; and -decoding bits of said lower order incoming values to higher order bits of said higher order data system if said indicating bit or bits indicate a compressed value. 18. An apparatus as claimed in claim 17 wherein said direct output of uncompressed values comprises logically connecting lower order bits of said incoming value to corresponding lower order bits of said higher order value and setting remaining bits of said higher order value to zero. 19. A method for the uncompression of transmitted or stored linearized data from a lower order data system into a higher order data system for use with a digital display where said linearized data comprises uncompressed values below at least a first threshold and compressed values above said at least first threshold and an indicating bit or bits to indicate the state of compression of the value comprising: -utilizing said indicating portion to switch the output between at least two alternative inputs; -a direct output of the incoming value if the indicating portion indicates an uncompressed value; and -decoding incoming data bits to higher order output data bits if said indicating bit or bits indicates a compressed value.