1. An apparatus comprising: a bitstream of a compressed picture stored on a non-transitory computer-readable storage medium, the stored bitstream comprising: quantized transform coefficients for a coded pixel region of the compressed picture, the quantized transform coefficients associated with a quantization parameter value, the quantization parameter value defining a transformation to be applied to the quantized transform coefficients during decoding of the coded pixel region; and a representational quantization parameter code for determining the quantization parameter value for the coded pixel region, the representational quantization parameter code selected from a set of quantization parameter codes having more than 32 distinct quantization parameter codes, each quantization parameter code in the set corresponding to a respective quantization parameter value, wherein a number of quantization parameter codes in the set of quantization parameter codes is dependent on a bit precision of the compressed picture, wherein the set of representational quantization parameter codes include (i) first quantization parameter codes and (ii) second quantization parameter codes having greater values than the first quantization parameter codes, wherein each quantization parameter code of the first quantization parameter codes corresponds linearly to a respective quantization parameter value, such that for each quantization parameter code of the first quantization parameter codes, a difference between (i) the respective corresponding quantization parameter value, and (ii) a quantization parameter value for a quantization parameter code that is adjacent to the respective first quantization parameter code, is a same constant value, wherein each quantization parameter code of the second quantization parameter codes corresponds non-linearly to a respective quantization parameter value.