[theora-dev] QRSIZES

Jonathan Fabrizio jonathan.fabrizio at lrde.epita.fr
Wed Mar 16 00:32:00 PDT 2011

     In the specification, QRSIZES is the size of the range for a given 
quant range (P 53).
     When I read the algorithm 6.4.2 (Quantization parameters decode) in 
7 (a) iv there is a loop in wich :
E. Assign qi the value qi + QRSIZES[qti ][pli ][qri ].
H. If qi is less than 63, go back to step 7(a)ivD.
I. If qi is greater than 63, stop. The stream is undecodable.

This means the loop stop when qi (and then, the sum of all 
QRSIZES[qti][pli][]) reaches exactly 63.
If I understand well, if I have only one quantification matrix, it must 
cover all possible qi, then the size of the quant range is 63.

Then I do not understand the value given page 151 for VP3 Quantification 
parameters. I agree with the values of NQRS and QRBMIS but according to 
the specification and the algorithm, I think that QRSIZES should be { 
{{63},{63},{63}},{{63},{63},{63}} } ?

Am I right ?



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