System and method for controlled dynamics adaptation for musical content
According to a preferred aspect, there is provided a system and method for controlled dynamics adaptation of audio works. The dynamics complexity of the audio is adapted depending on the listening environment and its dynamics properties. The instant invention utilizes a function of stepwise linear and logarithmical sections, which describe individual points of a curve and which therefore with the use of a parameter can be utilized to calculate and control the target value of the loudness range. The curve points are stored and provided as metadata of the musical program, which allows the dynamics scaling functionality to be implemented dynamically and not tied to a certain time or place.
1. A method of performing a digital audio work, comprising the steps of:
(a) accessing said digital audio work;
(b) determining a plurality of change points within said audio work, wherein each of said plurality of change points represents an amplitude of an expansion curve at a different point in time within said audio work;
(c) using said plurality of change points to determine a continuous expansion curve without jumps or gaps for said digital audio work that coincides in amplitude with each of said plurality of change point amplitudes;
(d) using said expansion curve to scale said digital audio work, thereby creating a scaled digital audio work;
(e) transmitting said scaled digital audio work and said expansion curve to a user at a user location;
(f) selecting LRA target , wherein LRA target is a target loudness range;
(g) selecting LRA current , wherein LRA current is a loudness range associated with said digital audio work;
(h) calculating D =LRA current /LRA target , wherein D is a compression parameter;
(i) using said expansion curve and utilizing the compression parameter 1/D to at least approximately recover said digital audio work from said scaled digital audio work; and,
(j) performing said at least approximately recovered digital audio work for the user at the user location.
2. A method of performing a digital audio work according to claim 1 , wherein said plurality of changes points are determined either automatically, semi-automatically or manually.
3. A method of performing a digital audio work according to claim 1 , wherein said audio work is selected from the group consisting of streamed audio material, an audio component of streamed video material, an audio file, and an audio component of a video file.
4. A method of performing a digital audio work according to claim 1 , wherein step (b) comprises the steps of:
(b1) performing a loudness measuring analysis on the audio work;
(b2) determining a plurality of change points from said loudness measuring analysis.
5. A method of performing a digital audio work, comprising the steps of:
(a) accessing said digital audio work;
(b) determining a plurality of non-overlapping time windows within said audio work,
wherein
(i) said plurality of windows taken together cover said audio work, and,
(ii) a starting time of each of said plurality of windows coincides with an ending time of an adjacent one of said plurality of windows;
(c) selecting a change point within each of said plurality of windows, thereby selecting a plurality of change points, each of said plurality of change points being associated with an audio gain value;
(d) using said plurality of change points to determine a continuous expansion curve for said digital audio work, said expansion curve coinciding in amplitude with each of said plurality of change point gain values,
wherein said continuous expansion curve comprises a plurality of connected line segments, each of said plurality of line segments having a first end point at a first one of said change points and a second end point at an adjacent one of said change points, and, wherein said plurality of line segments taken together form a continuous amplitude curve;
(e) using said expansion curve to scale said digital audio work, thereby creating a scaled digital audio work;
(f) transmitting said scaled digital audio work and said expansion curve to a user at a user location;
(g) selecting LRA target , wherein LRA target is a target loudness range;
(h) selecting LRA current , wherein LRA current is a loudness range associated with said digital audio work;
(i) calculating D =LRA current /LRA target , wherein D is a compression parameter;
(j) using said expansion curve and said compression parameter to at least approximately recover said digital audio work from said scaled digital audio work at a location of the user; and,
(k) performing said at least approximately recovered digital audio work for the user at the user location.
6. A method of performing a digital audio work according to claim 5 , wherein said plurality of changes points are determined either automatically, semi-automatically or manually.
7. A method of performing a digital audio work according to claim 5 , wherein said audio work is selected from the group consisting of streamed audio material, an audio component of streamed video material, an audio file, and an audio component of a video file.
8. A method of performing a digital audio work according to claim 5 , wherein step (d) comprises the steps of:
(d1) performing a loudness measuring analysis on the audio work;
(d2) using said loudness measuring analysis to determine said expansion curve amplitude at each of said change points.