Method and apparatus for screen related adaptation of a Higher-Order Ambisonics audio signal

A non-transitory computer readable medium containing instructions that when executed by at least one s-processor, cause the at least one processor to perform operations comprising:

• receiving a bit stream containing encoded HOA signals and metadata indicating a production screen size;
• determining the production screen size from the metadata;
• decoding the encoded HOA signals to obtain a first set of decoded HOA signals representing dominant components of the sound field and a second set of decoded HOA signals representing ambient components of the sound field;
• combining the first set of decoded HOA signals and the second set of decoded HOA signals to produce a combined set of decoded HOA signals;
• and
• determining a transformation matrix for warping the combined set of decoded HOA signals, wherein the transformation matrix is based on the production screen size and a target screen size, and wherein the transformation matrix is further based on a diagonal matrix of loudspeaker correction gains.

An apparatus for decoding encoded higher order ambisonics (HOA) signals describing a sound field, the apparatus comprising:

• a receiver for obtaining a bit stream containing the encoded HOA signals and metadata indicating a production screen size;
• a processor for determining the production screen size from the metadata;
• an audio decoder for decoding the encoded HOA signals to obtain a first set of decoded HOA signals representing dominant components of the sound field and a second set of decoded HOA signals representing ambient components of the sound field;
• a combiner for integrating the first set of decoded HOA signals and the second set of decoded HOA signals to produce a combined set of decoded HOA signals;
• and
• a processor for determining a transformation matrix for warping the combined set of decoded HOA signals, wherein the transformation matrix is based on the production screen size and a target screen size, and wherein the transformation matrix is further based on a diagonal matrix of loudspeaker correction gains.