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--- atrac3p:serialized_quantization_unit_levels [2010/10/25 12:23] – Mode3/master has first delta with offset when using extended base tables. megadiscman
+++ atrac3p:serialized_quantization_unit_levels [2010/10/25 13:01] (current) – Explain signs of level prediction vectors correctly. megadiscman
@@ Line 5: / Line 5: @@
 ==== Prediction Vectors ====
-The prediction vectors (common distributions) of the levels fall into two classes. Three [[basic level prediction vectors]] (one of them completely zero) and 64 different [[extended level prediction vectors]]. The prediction vectors are used in all non-primitive master encoding modes. While modes basing on the extended tables generally wrap around, modes based on the basic tables do not. The usage of the vectors for the levels is different from the precision prediction vectors in that they are subtracted and not added to the data, so the no-wraparound condition means that encoding a delta of 6 (i.e. +6) while the prediction vector says 8 (i.e. -8) is an error.
+The prediction vectors (common distributions) of the levels fall into two classes. Three [[basic level prediction vectors]] (one of them completely zero) and 64 different [[extended level prediction vectors]]. The prediction vectors are used in all non-primitive master encoding modes. While modes basing on the extended tables generally wrap around, modes based on the basic tables do not.
-If an extended prediction vector is selected, the entries from the extended prediction vector are offset by a 6-bit value stored directly adjacent to the extended prediction vector number. While the vector itself is (see above) to be interpreted negatively, the offset is positive.
+For the basic vectors only, the prediction vectors are to be subtracted from the data instead of added,so the no-wraparound condition means that encoding a delta of 6 (i.e. +6) while the prediction vector says 8 (i.e. -8) is an error.
+If an extended prediction vector is selected, the entries from the extended prediction vector are offset by a 6-bit value stored directly adjacent to the extended prediction vector number. The extended vector is taken positive unlike the basic vectors.
 ==== Encoding Modes ====