US 12,334,958 B2
Method and device for arithmetic encoding or arithmetic decoding
Oliver Wuebbolt, Hannover (DE)
Assigned to DOLBY LABORATORIES LICENSING CORPORATION, San Francisco, CA (US)
Filed by DOLBY LABORATORIES LICENSING CORPORATION, San Francisco, CA (US)
Filed on Sep. 12, 2023, as Appl. No. 18/465,479.
Application 17/092,648 is a division of application No. 16/677,539, filed on Nov. 7, 2019, granted, now 10,848,180, issued on Nov. 24, 2020.
Application 16/677,539 is a division of application No. 15/952,082, filed on Apr. 12, 2018, granted, now 10,516,414, issued on Dec. 24, 2019.
Application 15/952,082 is a division of application No. 14/924,156, filed on Oct. 27, 2015, granted, now 9,973,208, issued on May 15, 2018.
Application 18/465,479 is a continuation of application No. 17/854,866, filed on Jun. 30, 2022, granted, now 11,770,131, issued on Sep. 26, 2023.
Application 17/854,866 is a continuation of application No. 17/092,648, filed on Nov. 9, 2020, granted, now 11,381,249, issued on Jul. 5, 2022.
Application 14/924,156 is a continuation of application No. 13/500,106, granted, now 9,219,498, issued on Dec. 22, 2015, previously published as PCT/EP2010/064644, filed on Oct. 1, 2010.
Claims priority of application No. 09305961 (EP), filed on Oct. 9, 2009.
Prior Publication US 2023/0421174 A1, Dec. 28, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. H04N 11/02 (2006.01); H03M 7/40 (2006.01); H04N 19/124 (2014.01); H04N 19/182 (2014.01)
CPC H03M 7/4006 (2013.01) [H04N 19/124 (2014.11); H04N 19/182 (2014.11)] 3 Claims
OG exemplary drawing
 
1. A method of decoding current spectral coefficients of a current frame using preceding spectral coefficients of the current frame or a previous frame, the method comprising:
performing a first quantizing in which absolute values of the preceding spectral coefficients are quantized according to a first quantization scheme, wherein performing the first quantizing determines quantized preceding spectral coefficients;
determining a variance of the quantized preceding spectral coefficients, comprising determining a sum of the quantized preceding spectral coefficients and comparing the determined sum with at least one threshold;
using the determined variance for selecting one of at least two different non-linear second quantization schemes;
performing a second quantizing in which the quantized preceding spectral coefficients are further quantized according to the selected non-linear second quantization scheme, wherein the performing the second quantizing includes determining an output of the second quantizing;
determining a context class out of at least two different context classes, wherein the context class is determined based on the output of the second quantizing;
determining a probability density function using the determined context class and a mapping from the at least two different context classes to at least two different probability density functions, wherein the mapping is realized using a look-up table or a hash table;
arithmetic decoding a current spectral coefficient based on the probability density function,
the method further comprising:
receiving a mode switching signal or a reset signal; and
using the mode switching signal or the reset signal for controlling the determining of the context class, wherein, in response to the reset signal, only preceding spectral coefficients of the current frame are used for determining the context class.