US 12,328,451 B2
Methods and devices for encoding and decoding a data stream representing at least one image
Félix Henry, Chatillon (FR); Pierrick Philippe, Chatillon (FR); Mohsen Abdoli, Chatillon (FR); and Gordon Clare, Chatillon (FR)
Assigned to ORANGE, Issy-les-Moulineaux (FR)
Filed by ORANGE, Issy-les-Moulineaux (FR)
Filed on Mar. 26, 2024, as Appl. No. 18/616,937.
Application 18/616,937 is a continuation of application No. 17/277,938, granted, now 11,985,355, previously published as PCT/FR2019/052023, filed on Sep. 3, 2019.
Claims priority of application No. 1858572 (FR), filed on Sep. 21, 2018.
Prior Publication US 2024/0244266 A1, Jul. 18, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. H04N 19/70 (2014.01); H04N 19/105 (2014.01); H04N 19/176 (2014.01); H04N 19/182 (2014.01)
CPC H04N 19/70 (2014.11) [H04N 19/105 (2014.11); H04N 19/176 (2014.11); H04N 19/182 (2014.11)] 9 Claims
OG exemplary drawing
 
1. A method for decoding a coded data stream representative of at least one image, said image being split into blocks, wherein the method comprises the following acts implemented by a decoding device for at least one block of the image, referred to as a current block:
decoding an item of information indicating a coding mode of the current block,
determining that the coding mode of the current block corresponds to a first coding mode or a second coding mode;
when the coding mode of the current block corresponds to the first coding mode, decoding the current block comprising:
decoding coefficients of a prediction residue associated with the current block using a first group of syntax elements, said prediction residue being in the frequency domain and said first group of syntax elements comprising location syntax elements indicating the location of a first non-null coefficient of the prediction residue associated with said current block, according to a determined scanning order of the coefficients of said prediction residue,
obtaining a prediction of the current block from reconstructed pixels of a previously decoded block, and
reconstructing said current block from the prediction obtained and said decoded prediction residue; and
when the coding mode of the current block corresponds to the second coding mode, decoding the current block comprising:
decoding a prediction residue associated with the current block using a second group of syntax elements, said second group comprising at least one syntax element of said first group but not all the syntax elements of said first group and not comprising said location syntax elements, said prediction residue being in the spatial domain and comprising quantized prediction residues associated with pixels of the current block, and
reconstructing said current block comprising:
for each pixel of the current block:
obtaining a prediction of said pixel from at least one another previously reconstructed pixel, said at least one other previously reconstructed pixel belonging to said current block or to a previously reconstructed block of the image,
de-quantizing the quantized prediction residue associated with said pixel and comprised within the prediction residue associated with the current block and decoded using the second group of syntax elements, and
reconstructing said pixel from the prediction of said pixel obtained and from the de-quantized prediction residue associated with said pixel.