A method to identify media content, comprising: receiving a reference signal corresponding to known media content and generating a reference signature based on the reference signal, the reference signature comprising a first plurality of normalized curve features, wherein each one of the first plurality of normalized curve features comprises a respective shape having a respective first height, a respective first width, and a respective center location at a respective temporal location, and wherein heights of the reference signature are substantially zero at temporal locations not corresponding to the first plurality of normalized curve features; receiving a media signal corresponding to monitored media content; generating a plurality of sums of absolute values of peaks between zero crossings in the media signal, the plurality of sums corresponding to a plurality of time slots; identifying one or more peaks based on the generated sums, the one or more identified peaks having respective temporal locations; generating a second signature based on a second plurality of normalized curve features, wherein each one of the second plurality of normalized curve features comprises a respective shape having a respective second height, a respective second width, and a respective center location at a respective temporal location corresponding to the temporal location of a corresponding one of the identified peaks, wherein at least one of the respective second height or the respective second width is equal or proportional to at least one of a height or the temporal location of the corresponding one of the identified peaks, and wherein heights of the second signature are substantially zero at temporal locations not corresponding to the second plurality of normalized curve features; performing a correlation of the second signature and the reference signature; and determining whether the media signal corresponds to the reference signal based on the correlation. receiving a reference signal corresponding to known media content and generating a reference signature based on the reference signal, the reference signature comprising a first plurality of normalized curve features, wherein each one of the first plurality of normalized curve features comprises a respective shape having a respective first height, a respective first width, and a respective center location at a respective temporal location, and wherein heights of the reference signature are substantially zero at temporal locations not corresponding to the first plurality of normalized curve features; receiving a media signal corresponding to monitored media content; generating a plurality of sums of absolute values of peaks between zero crossings in the media signal, the plurality of sums corresponding to a plurality of time slots; identifying one or more peaks based on the generated sums, the one or more identified peaks having respective temporal locations; generating a second signature based on a second plurality of normalized curve features, wherein each one of the second plurality of normalized curve features comprises a respective shape having a respective second height, a respective second width, and a respective center location at a respective temporal location corresponding to the temporal location of a corresponding one of the identified peaks, wherein at least one of the respective second height or the respective second width is equal or proportional to at least one of a height or the temporal location of the corresponding one of the identified peaks, and wherein heights of the second signature are substantially zero at temporal locations not corresponding to the second plurality of normalized curve features; performing a correlation of the second signature and the reference signature; and determining whether the media signal corresponds to the reference signal based on the correlation.