1. A method for image coding, the method comprising: obtaining, at a video codec device, an image block; generating a color index map comprising a plurality of entries and representing the image block, wherein each one of the entries is assigned a color index indicating a respective color; determining whether each one of the entries is predictable by a neighboring entry in the color index map; assigning, in a correct prediction map, a first bit-value for each one of the entries that is predictable by a neighboring entry in the color index map; assigning, in the correct prediction map, a second bit-value for each one of the entries that is unpredictable by any neighboring entry in the color index map; and adding, in a sequence of non-predictable color indices, an actual value from the color index map for each one of the entries that is unpredictable by any neighboring entry.