A playback system is provided for altering the frame rate of streaming digital movie data for synchronizing with audio data recording to create a synchronized audiovisual work. The system can have a video that is synchronized with the variations in the tempo of the audio data through a variable timing reference track designed and provided for a user, wherein the designing of the variable timing reference track includes creating a tempo map having variable tempos, rhythms, and beats using notes from the audio data.

An information processing system includes an image obtaining circuit and a display control circuit. The image obtaining circuit is configured to obtain observation images of a first keyboard of a first keyboard instrument. The display control circuit is configured to display, on a display device, the observation images and reference images. The reference images include moving images of at least one hand and one or more fingers of a reference performer who is playing a second keyboard of a second keyboard instrument. The at least one hand and the one or more fingers of the reference performer are displayed overlapping the first keyboard included in the observation images.

Approaches provided herein can provide for adjustments to audio data. In particular, an audio resampling process can be performed wherein the correct audio frame size is determined. A target audio stream duration, as may be indicated by a time-to-sample atom (STTS) atom, can be used to apply one or more pitch-invariant, time-stretching audio filters to the audio data as that data is decoded during a media transcode process. A resulting output media metadata can specify accurate, constant audio frame durations, and the audio stream duration can match the corresponding video stream duration in a media file.

Systems and methods directed to combining audio tracks are provided. More specifically, a first audio track and a second audio track are received. The first audio track is separated into a vocal component and one or more accompaniment components. The second audio track is separated into a vocal component and one or more accompaniment components. A structure of the first audio track and a structure of the second audio track are determined. The first audio track and the second audio track are aligned based on the determined structures of the tracks. The vocal component of the first audio track is stretched to match a tempo of the second audio track. The stretched vocal component of the first audio track is added to the one or more accompaniment components of the second audio track.

A sound control device configured to mix a first music piece and a second music piece includes: a comparing section configured compare a BPM of the first music piece and a BPM of the second music piece; and an effect selecting section configured to select a sound effect according to a result of the comparison.

A playback system is provided for altering the frame rate of streaming digital movie data for synchronizing with audio data recording to create a synchronized audiovisual work. The system can have a video that is synchronized with the variations in the tempo of the audio data through a variable timing reference track designed and provided for a user, wherein the designing of the variable timing reference track includes creating a tempo map having variable tempos, rhythms, and beats using notes from the audio data.