Patent ID: 8218861

Claim:
A computer-implemented method for digital image processing, the method comprising: processing, by a computer system, encoded digital data which comprise encoding of digital data representing an image at a plurality of image portions, wherein the image comprises the plurality of image portions, wherein an image at each said image portion has color coordinates S 1 , S 2 , S 3 in a first color coordinate system (CCS), wherein S 1 =√{square root over ( T 1 2 +T 2 2 +T 3 2 )} S 2 =T 2 /S 1 S 3 =T 3 /S 1 T 1 , T 2 , T 3 are color coordinates in a predefined 70%-orthonormal linear CCS; wherein at least for each said image portion whose color coordinate S 1 is in a predefined range, the encoded digital data comprise color coordinates s 1 , s 2 , s 3 such that: s 1 =k B ·(ln(αS 1 )+β) rounded to an integer, where α and β are predefined constants, s 2 =k ef ·S 2 /S 1 rounded to an integer, s 3 =k ef ·S 3 /S 1 rounded to an integer, wherein k ef is about 3·k B , or k ef is equal to the smallest power of 2 which is greater than or equal to about 3·k B ; wherein processing the encoded digital data comprises using the encoded digital data to perform at least one of: editing the image; displaying the image on a display device; decoding the encoded digital data.