Abstract: A source device uses a profile of an audio output device (e.g., headphones or speakers) to adjust the acoustic output of the audio output device. A database of audio output device profiles is stored in a cloud or locally on the source device. The profiles may include electroacoustic measurement data characterizing the audio output device or processing parameters for the audio output device. A program running on the source device selects a profile corresponding to the connected audio output device. The profile is used by the software running on the source device to determine processing for an audio stream played by the audio output device. The processing provides equalization to modify the unique audio output device frequency response, and compensation for human perception of sound at different listening levels, and dynamic range adjustment to better match the capabilities of the audio output device.

Abstract: A speech/music discrimination method evaluates the standard deviation between envelope peaks, loudness ratio, and smoothed energy difference. The envelope is searched for peaks above a threshold. The standard deviations of the separations between peaks are calculated. Decreased standard deviation is indicative of speech, higher standard deviation is indicative of non-speech. The ratio between minimum and maximum loudness in recent input signal data frames is calculated. If this ratio corresponds to the dynamic range characteristic of speech, it is another indication that the input signal is speech content. Smoothed energies of the frames from the left and right input channels are computed and compared. Similar (e.g., highly correlated) left and right channel smoothed energies is indicative of speech. Dissimilar (e.g., un-correlated content) left and right channel smoothed energies is indicative of non-speech material. The results of the three tests are compared to make a speech/music decision.

Abstract: A source device uses a profile of an audio output device (e.g., headphones or speakers) to adjust the acoustic output of the audio output device. A database of audio output device profiles is stored in a cloud or locally on the source device. The profiles may include electroacoustic measurement data characterizing the audio output device or processing parameters for the audio output device. A program running on the source device selects a profile corresponding to the connected audio output device. The profile is used by the software running on the source device to determine processing for an audio stream played by the audio output device. The processing provides equalization to modify the unique audio output device frequency response, and compensation for human perception of sound at different listening levels, and dynamic range adjustment to better match the capabilities of the audio output device.