transformation u201d transforms the input samples into the variables to be quantized this block corresponds generally to the portion of fig2 enclosed by the dashed lines the block labeled u201c process entropy coding u201d assembles an encoded bitstream after entropy coding the quantized variables similarly for the decoder in fig7 b the block labeled u201c process entropy decoding u201d parses encoded bitstream and entropy decodes the entropy coded quantized variables the block labeled u201c process reconstruction u201d reconstructs the output samples from the decoded and dequantized variables and corresponds generally to the portion of fig3 enclosed by the dashed line the encoder shown in fig7 a receives input symbols s of n bits and transforms them into a sequence of variables x having n k bits where k is a function of the u201c process transformation u201d block and is typically greater than zero the encoder is also provided with a qp value and the bit depth n of the input symbols s each variable x is quantized by a quantizing step size qs n appropriate for a sample bit depth of n qs n is determined by a mapping from qp to qs 8 followed by the normalization given by equation 7 the resulting quantized variables are entropy coded and combined with n qp and other parameters to produce an encoded bitstream in practice qp needs to be sent in the bitstream only when it changes sending n is useful for indicating that drift reduction is required if m lt n or that emulation of lower precision arithmetic in.