Loudness control for user interactivity in audio coding systems

Audio encoder for generating an audio signal comprising a plurality of groups, each group comprising one or more audio elements, and metadata, comprising:

• a loudness determiner for determining a loudness value for at least one group of the plurality of groups, the at least one group comprising one or more audio elements;
• a controller for determining which group of the plurality of groups is to be used for determining a loudness compensation gain and which group of the plurality of groups is to be neglected for determining the loudness compensation gain;
• and
• a metadata writer for introducing the determined loudness value as a group loudness into the metadata and for writing an indication into the metadata indicating which group of the plurality of groups is to be used and which group of the plurality of groups is to be neglected for determining the loudness compensation gain.

Method for processing an audio signal, the audio signal comprising a plurality of groups, each group comprising one or more audio elements, and metadata, the metadata indicating which group of the plurality of groups is to be used or is not to be used for determining a loudness compensation gain, the method comprising:

• modifying one or more groups of the plurality of groups of the audio signal in response to a user input to acquire a modified signal;
• determining the loudness compensation gain based, on the one hand, on a reference loudness or a reference gain corresponding to an original audio scene and the metadata indicating which group of the plurality of groups is to be used or is not to be used for determining the loudness compensation gain, and, on the other hand, on a modified loudness or a modified gain, wherein the modified loudness or the modified gain depends on the user input,
• wherein the metadata indicates that a first group of the plurality of groups is not to be used for determining the loudness compensation gain, and wherein the metadata indicates that a second group of the plurality of groups is to be used for determining the loudness compensation gain, and
• wherein the loudness compensation gain is determined using excluding the first group in a calculation of the reference loudness or the reference gain, and including the second group in the calculation of the reference loudness or the reference gain;
• and
• manipulating a loudness of the modified signal using the loudness compensation gain.

Method for generating an audio signal comprising a plurality of groups, each group comprising one or more audio elements, and metadata, the method comprising:

• determining a loudness value for at least one group of the plurality of groups, the at least one group comprising one or more audio elements;
• determining which group of the plurality of groups is to be used for determining a loudness compensation gain and which group of the plurality of groups is to be neglected for determining the loudness compensation gain;
• and
• introducing the determined loudness value for the group as a group loudness into the metadata and writing an indication into the metadata indicating which group of the plurality of groups is to be used and which group of the plurality of groups is to be neglected for determining the loudness compensation gain.

A non-transitory digital storage medium having a computer program stored thereon to perform the method for processing an audio signal, the audio signal comprising a plurality of groups, each group comprising one or more audio elements, and metadata, the metadata indicating which group of the plurality of groups is to be used or is not to be used for determining a loudness compensation gain, the method comprising:

• modifying one or more groups of the plurality of groups of the audio signal in response to a user input to acquire a modified signal;
• determining the loudness compensation gain based, on the one hand, on a reference loudness or a reference gain corresponding to an original audio scene and the metadata indicating which group of the plurality of groups is to be used or is not to be used for determining the loudness compensation gain, and, on the other hand, on a modified loudness or a modified gain, wherein the modified loudness or the modified gain depends on the user input,
• wherein the metadata indicates that a first group of the plurality of groups is not to be used for determining the loudness compensation gain, and wherein the metadata indicates that a second group of the plurality of groups is to be used for determining the loudness compensation gain, and
• wherein the loudness compensation gain is determined using excluding the first group in a calculation of the reference loudness or the reference gain, and including the second group in the calculation of the reference loudness or the reference gain;
• and
• manipulating a loudness of the modified signal using the loudness compensation gain,
• when said computer program is run by a computer.

A non-transitory digital storage medium having a computer program stored thereon to perform the method for generating an audio signal comprising a plurality of groups, each group comprising one or more audio elements, and metadata, the method comprising:

• determining a loudness value for at least one group of the plurality of groups, the at least one group comprising one or more audio elements;
• determining which group of the plurality of groups is to be used for determining a loudness compensation gain and which group of the plurality of groups is to be neglected for determining the loudness compensation gain;
• and
• introducing the determined loudness value for the group as a group loudness into the metadata and writing an indication into the metadata indicating which group of the plurality of groups is to be used and which group of the plurality of groups is to be neglected for determining the loudness compensation gain,
• when said computer program is run by a computer.