Intra block copy with template matching for video encoding and decoding

A method comprising:

• determining a template based on samples surrounding a block of a picture of a video;
• determining an initial location for an initial iteration;
• selecting a matching template among a set of template candidates in reconstructed blocks of the picture, wherein the set of template candidates is determined based on a determined location and wherein the matching template is selected based on a similarity measure between samples of the template and samples of the template candidates;
• refining the selection by iterating over the selection step while the similarity of a template candidate is better than the similarity of the other template candidates;
• and
• reconstructing the block by copying samples of the selected matching template into the block,
• wherein, for the initial iteration over the selection step, the location is determined by the initial location and wherein, for further iterations, the location is determined as a refinement based on the location of the selected matching template of the previous iteration.

An apparatus for video decoding, the apparatus comprising one or more processors configured to:

• determine a template based on samples surrounding a block of a picture of a video;
• determine an initial location for an initial iteration;
• select a matching template among a set of template candidates in reconstructed blocks of the picture, wherein the set of template candidates is determined based on a determined location and wherein the matching template is selected based on a similarity measure between samples of the template and samples of the template candidates;
• refine the selection by iterating over the selection step while the similarity of a template candidate is better than the similarity of the other template candidates;
• reconstruct the block by copying samples of the selected matching template into the block, wherein, for the initial iteration over the selection step, the location is determined by the initial location and wherein, for further iterations, the location is determined as a refinement based on the location of the selected matching template of the previous iteration;
• and
• decode picture data using the reconstructed block.

An apparatus for video encoding, the apparatus comprising one or more processors configured to:

• determine a template based on samples surrounding a block of a picture of a video;
• determine an initial location for an initial iteration;
• select a matching template among a set of template candidates in reconstructed blocks of the picture, wherein the set of template candidates is determined based on a determined location and wherein the matching template is selected based on a similarity measure between samples of the template and samples of the template candidates;
• refine the selection by iterating over the selection step while the similarity of a template candidate is better than the similarity of the other template candidates;
• reconstruct the block by copying samples of the selected matching template into the block, wherein, for the initial iteration over the selection step, the location is determined by the initial location and wherein, for further iterations, the location is determined as a refinement based on the location of the selected matching template of the previous iteration;
• and
• encode picture data using the reconstructed block.