A service receives a request from a user of a group of users to perform one or more operations requiring group authentication in order for the operations to be performed. In response, the service provides a first user of the group with an image seed and an ordering of the group of users. Each user of the group applies a transformation algorithm to the seed to create an authentication claim. The service receives this claim and determines, based at least in part on the ordering of the group of users, an ordered set of transformations, which are used to create a reference image file. If the received claim matches the reference image file, the service enables performance of the requested one or more operations.

There is provided a post processing technique or method for separation algorithms to separate vocals from monaural music recordings. The method comprises detecting traces of pitched instruments in a magnitude spectrum of a separated voice using Hough transform and removing the detected traces of pitched instruments using median filtering to improve the quality of the separated voice and to form a new separated music signal. The method further comprises applying adaptive median filtering techniques to remove the identified Hough regions from the vocal spectrogram producing separated pitched instruments harmonics and new vocals while adding the separated pitched instruments harmonics to a music signal separated using any separation algorithm to form the new separated music signal.

Computer-based systems, devices, and methods for generating musical compositions are described. A population of musical compositions stored in digital media are each segmented to produce abridged samples. The samples are analyzed to identify parent compositions that best exhibit or evoke a particular desired quality. The parent compositions are cross-bred to generate a set of child compositions which are similarly segmented and analyzed. The child compositions that best exhibit or evoke the particular desired quality are re-cast as parent compositions from which another generation of child compositions are bred. Mutations in the form of musical variations are inserted in at least some iterations and the process is repeated until at least one child composition that satisfies some exit criterion is returned.

Methods, systems and apparatus to characterize audio using transchromagrams are disclosed. An example apparatus includes a transchromagram generator to generate a data structure based on a set of transition matrices corresponding to a plurality of time frames of audio data, the data structure indicative of probabilities that first musical notes will transition to second musical notes, a database controller to prompt a database to store the data structure within the audio data, and a notification manager to generate, based on a comparison between query audio data and the stored data structure of the audio data, a notification identifying at least one characteristic of the query audio data.

Devices and methods for improving the field of signal generation are provided by transforming computer images into signals. In some embodiments the invention relates to computer music synthesis applications. Other applications include but are not limited to, speech, text, numerical, digital or analogue signals, and other signals that can be generated from images. Some embodiments include an electronic display or displays, and one or more input devices, processors and output devices.

An apparatus for analysing a magnitude spectrogram of an audio signal is provided. The apparatus includes a frequency change determiner being configured to determine a change of a frequency for each time-frequency bin of a plurality of time-frequency bins of the magnitude spectrogram of the audio signal depending on the magnitude spectrogram of the audio signal. Moreover, the apparatus includes a classifier being configured to assign each time-frequency bin of the plurality of time-frequency bins to a signal component group of two or more signal component groups depending on the change of the frequency determined for the time-frequency bin.

There is provided a post processing technique or method for separation algorithms to separate vocals from monaural music recordings. The method comprises detecting traces of pitched instruments in a magnitude spectrum of a separated voice using Hough transform and removing the detected traces of pitched instruments using median filtering to improve the quality of the separated voice and to form a new separated music signal. The method further comprises applying adaptive median filtering techniques to remove the identified Hough regions from the vocal spectrogram producing separated pitched instruments harmonics and new vocals while adding the separated pitched instruments harmonics to a music signal separated using any separation algorithm to form the new separated music signal.

Musical catalog amplification services that leverage or deploy a computer-based musical composition system are described. The computer-based musical composition system employs algorithms and, optionally, artificial intelligence to generate new music based on analyses of existing music. The new music may be wholly distinctive from, or may include musical variations of, the existing music. Rights in the new music generated by the computer-based musical composition system are granted to the rights holder(s) of the existing music. In this way, the musical catalog(s) of the rights holder(s) is/are amplified to include additional music assets. The computer-based musical composition system may be tuned so that the new music sounds more like, or less like, the existing music of the rights holder(s). Revenues generated from the new music are shared between the musical catalog amplification service provider and the rights holder(s).

Methods, systems and apparatus to characterize audio using transchromagrams are disclosed. An example method includes generating, by executing one or more instructions on a processor, a set of transition matrices based on a plurality of time frames of the audio data, each of the plurality of transition matrices generated based on a different pair of time frames in the plurality of time frames, and indicating probabilities that anterior musical notes in an anterior time frame of the pair transition to posterior musical notes in a posterior time frame of the pair, generating, by executing one or more instructions on a processor, a data structure representing how the audio data changes statistically between the plurality of time frames based on the set of transition matrices, and causing, by executing one or more instructions on a processor, a database to store the data structure within metadata that describes the audio data.

An audio data processing method and apparatus are provided. The method includes obtaining audio data. An overall spectrum of the audio data is obtained and separated into a singing voice spectrum and an accompaniment spectrum. An accompaniment binary mask of the audio data is calculated according to the audio data. The singing voice spectrum and the accompaniment spectrum are processed using the accompaniment binary mask, to obtain accompaniment data and singing voice data.