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US 12,701,231 B2Granted
Quantization of residuals in video coding
AssigneeV-Nova International Limited
InventorsGuido Meardi, Simone Ferrara, Lorenzo Ciccarelli
Life of this patent
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Abstract
A method of decoding an encoded signal is provided, said encoded signal received within a bitstream, the method comprising: receiving a set of quantized data associated with the encoded signal; determining at least one dequantization parameter; and dequantizing the quantized data based at least in part of the at least one dequantization parameter.
Claims15
A method of decoding an encoded signal received within a bitstream, the method comprising:
- receiving the bitstream comprising the encoded signal, the bitstream comprising a first portion and a second portion, the first portion comprising quantized data that, when decoded, results in decoded data, the second portion comprising a first sub-portion indicating a dequantization parameter to be used for dequantizing the quantized data within the first portion and comprising a second sub-portion that indicates a process to be used for dequantizing the quantized data within the first portion;
- accessing a set of quantized data associated with the encoded signal from within the first portion of the bitstream;
- determining at least one dequantization parameter from the first sub-portion of the second portion of the bitstream;
- determining from the second sub-portion of the second portion of the bitstream the process which will be used for dequantizing the quantized data of the first portion;
- dequantizing the quantized data using the process determined from the second sub-portion and based at least in part on the at least one dequantization parameter determined from the first sub-portion;
- wherein the quantized data comprises a plurality of subsets of quantized data, and wherein the at least one dequantization parameter comprises a plurality of dequantization parameters, each one of the plurality of dequantization parameters corresponding to a respective one of the plurality of subsets of quantized data, and wherein the dequantizing operation further comprises dequantizing each of the plurality of subsets of quantized data based at least in part on its respective dequantization parameter from the plurality of dequantization parameters;
- wherein the plurality of dequantization parameters comprises at least a quantization step width parameter, said quantization step width parameter received in the bitstream, and at least one scaling factor, wherein the at least one scaling factor comprises a plurality of scaling factors, each of the plurality of scaling factors corresponding to a respective one of the plurality of subsets of quantized data, wherein determining the at least one dequantization parameter comprises deriving a plurality of dequantization parameters, each of the plurality of dequantization parameters being obtained by processing the quantization step width parameter with a respective one of the plurality of scaling factors;
- wherein actual quantization parameters SW(s)actual are computed by processing a received quantization step width parameter SWsignalled with scaling factors SF(s)computed, by a function of at least these two factors according to:
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129 more elements
A decoder for decoding an encoded stream into a reconstructed output video, the decoder being configured to:
- receive the bitstream comprising the encoded signal, the bitstream comprising a first portion and a second portion, the first portion comprising quantized data that, when decoded, results in decoded data, the second portion comprising a sub-portion indicating a dequantization parameter to be used for dequantizing the quantized data within the first portion and comprising a second sub-portion that indicates a process to be used for dequantizing the quantized data within the first portion;
- access a set of quantized data associated with the encoded signal from within the first portion of the bitstream;
- determine at least one dequantization parameter from the first sub-portion of the second portion of the bitstream;
- determine from the second sub-portion of the second portion of the bitstream the process which will be used for dequantizing the quantized data of the first portion;
- dequantize the quantized data using the process determined from the second sub-portion and based at least in part of the at least one dequantization parameter determined from the first sub-portion;
- wherein the quantized data comprises a plurality of subsets of quantized data, and wherein the at least one dequantization parameter comprises a plurality of dequantization parameters, each one of the plurality of dequantization parameters corresponding to a respective one of the plurality of subsets of quantized data, and wherein the dequantizing operation further comprises dequantizing each of the plurality of subsets of quantized data based at least in part on its respective dequantization parameter from the plurality of dequantization parameters;
- wherein the plurality of dequantization parameters comprises at least a quantization step width parameter, said quantization step width parameter received in the bitstream, and at least one scaling factor, wherein the at least one scaling factor comprises a plurality of scaling factors, each of the plurality of scaling factors corresponding to a respective one of the plurality of subsets of quantized data, wherein determining the at least one dequantization parameter comprises deriving a plurality of dequantization parameters, each of the plurality of dequantization parameters being obtained by processing the quantization step width parameter with a respective one of the plurality of scaling factors;
- wherein actual quantization parameters SW(s)actual are computed by processing a received quantization step width parameter SWsignalled with scaling factors SF(s)computed, by a function of at least these two factors according to:
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128 more elements
A non-transitory computer-readable storage medium storing instructions that, when executed by a processor, cause the processor to:
- receive the bitstream comprising the encoded signal, the bitstream comprising a first portion and a second portion, the first portion comprising quantized data that, when decoded, results in decoded data, the second portion comprising a sub-portion indicating a dequantization parameter to be used for dequantizing the quantized data within the first portion and comprising a second sub-portion that indicates a process to be used for dequantizing the quantized data within the first portion;
- access a set of quantized data associated with the encoded signal from within the first portion of the bitstream;
- determine at least one dequantization parameter from the first sub-portion of the second portion of the bitstream;
- determining from the second sub-portion of the second portion of the bitstream the process which will be used for dequantizing the quantized data of the first portion;
- dequantize the quantized data using the process determined from the second sub-portion and based at least in part of the at least one dequantization parameter determined from the first sub-portion;
- wherein the quantized data comprises a plurality of subsets of quantized data, and wherein the at least one dequantization parameter comprises a plurality of dequantization parameters, each one of the plurality of dequantization parameters corresponding to a respective one of the plurality of subsets of quantized data, and wherein the dequantizing operation further comprises dequantizing each of the plurality of subsets of quantized data based at least in part on its respective dequantization parameter from the plurality of dequantization parameters;
- wherein the plurality of dequantization parameters comprises at least a quantization step width parameter, said quantization step width parameter received in the bitstream, and at least one scaling factor, wherein the at least one scaling factor comprises a plurality of scaling factors, each of the plurality of scaling factors corresponding to a respective one of the plurality of subsets of quantized data, wherein determining the at least one dequantization parameter comprises deriving a plurality of dequantization parameters, each of the plurality of dequantization parameters being obtained by processing the quantization step width parameter with a respective one of the plurality of scaling factors;
- wherein actual quantization parameters SW(s)actual are computed by processing a received quantization step width parameter SWsignalled with scaling factors SF(s)computed, by a function of at least these two factors according to:
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- wherein the function f(⋅) is a multiplication according to:
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- wherein the dequantization operation comprises dequantized data being computed as
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- wherein qi(⋅) is the quantized data subset, and
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- is the actual quantization step for the i-th quantized data subset.
128 more elements
Dependencies are inferred from the claim text.