A method for color index coding of blocks in a picture is disclosed. In one embodiment for the decoder side, a current coding mode is parsed from the input coded bitstream for one or more first currently decoded pixels in a current block starting from a first starting position. If the current coding mode corresponds to a generalized copy-previous-row mode, one or more first reference pixels starting from a first starting reference position located at T-th row above the first currently decoded pixels are identified, where T is an integer equal to or greater than one. The first reference pixels starting from the first starting reference position are then used to decode the first currently decoded pixels starting from a first starting position by copying the first reference pixels starting from the first starting reference position respectively. The system may also include a copy-left mode or escape mode.