8.0

individual pixels of the block, but the values in the matrix are ordered in such a way that the image
information is ordered according to its importance.
This matrix will then be multiplied by another matrix, i.e. the quantization matrix
. Exactly how and why this matrix must be created is the biggest secret of encoder programmers, since
this determines the quality of the whole encoding process. What is known is that the result should contain
as many zeros as possible! These zeros correspond to the "unimportant" image elements mentioned and
will not be transmitted in the data stream.
Depending on the encoder parameters regarding the target bit rate, fewer or more values of the matrix
will be declared unimportant by dividing the quantization matrix by the quantization scaling factor
. Since only whole numbers are used, a division can produce a zero is the remainder is discarded.
This factor is also a direct measure of the sought image quality of the MPEG data stream, since the "Q" in
"Q" factor stands for quantization and quality.
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