Data encoding and decoding

A video decoding apparatus comprising:

• circuitry configured to
• perform, with respect to video blocks of spatial frequency data, frequency transformation by applying a frequency transformation to generate blocks of video data samples which are each scaled, and
• dequantize by selecting an index value in a table of six values in which, for an index value, a corresponding index scale is provided,
• wherein the index value is selected by performing, by the circuitry, a modulo 6 operation on a quantization parameter, and
• wherein at least some of the values in the table are used for coefficients of a video block which are not a power of 4 in size.

A video decoding method comprising:

• performing, with respect to video blocks of spatial frequency data, frequency transformation by applying a frequency transformation to generate blocks of video data samples which are each scaled;
• dequantizing by selecting an index value in a table in which, for an index value, an index scale value is provided;
• and
• selecting the index value by performing via circuitry a modulo 6 operation on a quantization parameter,
• wherein the index scale values in the table include values 40, 45, 51, 57, 64 and 72.

A video decoding method comprising:

• performing, with respect to video blocks of spatial frequency data, frequency transformation by applying a frequency transformation to generate blocks of video data samples which are each scaled;
• dequantizing by selecting an index value in a table of six values in which, for an index value, a corresponding index scale is provided;
• and
• selecting the index value by performing via circuitry a modulo 6 operation on a quantization parameter,
• wherein at least some of the values in the table are used for coefficients of a video block in which are not a power of 4 in size.